Phẫu Thuật Tạo Hình Grabb & Smith’s (Bản Cập Nhật – Kevin C. Chung)

Indications for Marginal and Segmental Mandibulectomy
Preoperative imaging is used to determine the extent of bony involvement of the mandible or maxilla.
Intraoperatively, the periosteum may be stripped in tumors abutting the mandible to inspect the
underlying bone. When bone invasion is limited to the periosteum or there is minimal cortical
involvement, a marginal mandibulectomy (single cortex) may be performed, but medullary invasion
requires a segmental (full-thickness) mandibular resection (Figure 37.4). 10
FIGURE 37.4 Gingival cancer invading the mandible seen in a surgical specimen (A). Computed tomography (CT) scan
demonstrating mandibular invasion of the buccal cortex extending to the medullary cavity (arrow) (B).
mebooksfree.net

Cervical Lymphadenectomy
Cervical lymphadenectomy or neck dissection has evolved over the past several decades.
Radical neck dissection (RND): en bloc removal of lymph nodes from levels I-V along with the
sternocleidomastoid muscle (SCM), internal jugular vein (IJV), and spinal accessory nerve (SAN)
(Figure 37.5)
Modified radical neck dissection (MRND): removal of all lymph node groups removed in a RND, but
with preservation of one or more nonlymphatic structures (SCM, IJV, and SAN). Sparing of all three
of these nonlymphatic structures is sometimes referred to as a functional neck dissection.
Selective neck dissection (SND): cervical lymphadenectomy with preservation of one or more lymph
node groups that are routinely removed in an RND or MRND
mebooksfree.net

FIGURE 37.5 Levels of the neck. Level I is the submental and submandibular triangles. Level II, the upper jugular group,
extends from the skull base to the carotid bifurcation (surgical landmark) or hyoid bone (clinical landmark). Level III, the middle
jugular group, extends from the carotid bifurcation/hyoid bone to the omohyoid muscle (surgical landmark) or cricothyroid notch
(clinical landmark). Level IV, the lower jugular group, extends from the omohyoid muscle to the clavicle. Level V is the posterior
triangle bounded by the posterior border of the sternocleidomastoid muscle, the anterior border of the trapezius, and the
clavicle. Level VI is the anterior (central) compartment.
Regional control and survival rates have not been found to decrease with selective approaches,
particularly with the addition of adjuvant therapies to manage microscopic residual disease. 32
Increasingly, lymph node yield and lymph node density are emerging as valuable quality indicators for
mebooksfree.net

neck dissection, with potential prognostic implication. 33
Lymphatic drainage of the oral cavity usually occurs first to levels I-III or I-IV. Thus for oral cavity
cancers, SND (I-III) or SND (I-IV) is commonly performed; more midline structures such as the lip and
anterior oral tongue may spread to ipsilateral or contralateral nodes, so both necks should be investigated
for such primary lesions. 10,30 SND (I-III) is also known as a supraomohyoid neck dissection. Sentinel
lymph node biopsy for oral cavity cancer seems to be a safe and reliable technique to stage the N0 neck in
oral cavity cancers, although further studies are ongoing. 12,34 For oropharyngeal, hypopharyngeal, and
laryngeal cancers, SND (II-IV) is the procedure of choice. 30
In patients with early-stage tumors that are clinically N0, the decision to proceed with neck dissection is
based on having a probability of >20% of occult lymph node metastases. Bilateral neck dissections may be
indicated when nodal metastases are present bilaterally or when a large midline primary tumor is present
and there is a high probability of bilateral occult metastases (e.g., in the base of the tongue, the
supraglottis, or the floor of the mouth). 10,30 RND and MRND are usually reserved for advanced nodal
disease and disease extending into level V or invasion of critical structures in the neck. 30
mebooksfree.net

Adjuvant Therapy
As mentioned, surgery with postoperative radiation or combined radiation and chemotherapy has
become the accepted treatment for high-stage head and neck cancers and those with adverse prognostic
risk factors. 35 During the past decade, intensity-modulated radiation therapy has replaced standard
delivery radiotherapy with decreased radiation-associated toxicity, particularly xerostomia. 36 It is an
advanced form of radiation therapy that uses multiple radiation beams of varying intensities coming
from different angles to precisely irradiate a tumor and avoid or reduce exposure of healthy tissue. More
recently, intensity-modulated proton therapy (IMPT) has been used in head and neck cancer. 37 It may
further reduce radiation-associated toxicity because of the decreased dose of radiation distal to the
planned target. Besides xerostomia, other side effects of all forms of radiation include dermatitis, nausea
and vomiting, fatigue, mucosal sores, hoarseness, and loss of taste. 37 Long-term problems may include
dental decay, osteoradionecrosis, hypothyroidism, vascular disease, hypopituitarism if the pituitary
gland is irradiated, and decreased hearing or vision when the orbits or middle ear/temporal bone are
irradiated. 35
Cisplatin is the chemotherapeutic drug most commonly used in head and neck cancer treatment
regimens. It may be used alone or may be combined with 5-fluorouracil if given after radiation. Other
agents include carboplatin, doxorubicin, epirubicin, paclitaxel, docetaxel, gemcitabine, bleomycin, and
methotrexate. Combinations of two or more of these drugs are often used. Cisplatin is associated with
neuropathies, especially peripheral neuropathy and hearing loss. Other side effects of chemotherapy
agents include hair loss, mouth sores, loss of appetite, nausea and vomiting, diarrhea,
immunosuppression, thrombocytopenia, and anemia. 4
Targeted therapy works differently from standard chemotherapy drugs and often has different side
effects. Targeted therapies consist of monoclonal antibodies that target specific protein receptors involved
in the cancer pathway. Cetuximab effectively targets the epidermal growth factor receptor, a
transmembrane tyrosine kinase receptor that is overexpressed in the majority of head and neck cancers
and leads to division, angioinvasion, and metastasis through Ras and PI3K. Cetuximab has been
demonstrated to be superior to radiation therapy alone and has become an integral component of
systemic therapy for UADT SCC, although its efficacy remains undetermined compared with platin-
based regimens. 38–40 Recently, immunotherapy with agents targeted against the PD-1 or PD-L1
checkpoint, such as pembrolizumab and nivolumab, has demonstrated prolonged disease-free survival in
a subset of patients with recurrent or refractory head and neck cancer. 41,42
mebooksfree.net

Salivary Gland Tumors
Salivary gland tumors represent a diverse group of neoplasms involving the major and minor salivary
glands. Tumors may arise from the various myoepithelial, ductal, and acinic components of the gland.
Besides salivary gland epithelial neoplasms, the differential diagnosis for swelling in the region of the
major glands includes metastatic cutaneous carcinoma (melanoma or SCC), lymphoma, hemangioma,
tuberculosis, HIV, and lymphadenopathy. 43
mebooksfree.net

Anatomy
Salivary glands include the parotid, submandibular, and sublingual glands (Figure 37.6). There are 800 to
1000 minor salivary glands located throughout the oral cavity beneath the buccal, labial, and lingual
mucosa; the soft palate; the lateral parts of the hard palate; and the floor of the mouth or between muscle
fibers of the tongue. The minor salivary glands are 1 to 2 mm in diameter and, unlike the major glands,
are not encapsulated by connective tissue, only surrounded by it.
FIGURE 37.6 Anatomy of the major salivary glands, showing the parotid, submandibular, and sublingual glands.
mebooksfree.net

Incidence and Risk Factors
Salivary gland tumors are rare, with fewer than 15 cases per 100,000 individuals annually. 43 About 80%
of salivary gland tumors are benign. 43 Primary salivary gland malignancies represent less than 5% of all
new head and neck cancers. About 80% of salivary gland tumors occur in the parotid glands, followed by
the submandibular and minor salivary glands, and only about 1% occur in the sublingual glands. About
80% of parotid gland tumors are benign, and the parotid gland is the most common location for salivary
gland malignancies; about 50% of submandibular gland tumors and 80% of minor salivary gland tumors
are malignant. 43
Rapid growth as well as pain and/or paresthesias caused by perineural invasion are associated with
malignancy. In the parotid gland, facial paralysis may be indicative of facial nerve invasion of a
malignant tumor. Nodal metastases may also be seen in malignant tumors.
mebooksfree.net

Preoperative Considerations
Biopsies, Imaging, and Metastatic Workup
Ultrasound, CT, and MRI are commonly used to evaluate salivary gland lesions. Contrast enhancement
does not distinguish between benign versus malignant tumors but can delineate the extent of the lesion.
Irregular margins, bony invasion, and the presence of metastatic lymph nodes or perineural spread can
all be signs of malignancy; perineural spread may be apparent by widening of a nerve or neural
foramina/space on CT scan, as well as by asymmetric enhancement or thickening on MRI. PET-CT is
helpful for detecting disease recurrence and distant metastases. 44
Ultrasound-guided FNA cytology is widely used but controversial because it has different levels of
accuracy based on tumor type. FNA is reported to correctly diagnose tumor type in 61% to 94% of cases
and differentiate between benign and malignant tumors in 81% to 98% of cases. 45,46 Because of this lack of
complete accuracy, FNA alone should not be used to dictate the extent of surgery, such as radical
resection or cervical lymphadenectomy. Some clinicians will choose to observe a lesion that is benign by
FNA in patients deemed poor candidates for surgery. In all other patients, surgery is usually indicated for
salivary gland neoplasms regardless of FNA results. The challenge for the extirpative surgeon is to
correctly determine the appropriate extent of surgical treatment, taking into account not only results from
FNA but also the preoperative and intraoperative findings, including those of frozen section examination,
which has limitations in terms of making an accurate diagnosis as well. When the exact diagnosis is
equivocal, the full scope of treatment should not be determined until final diagnosis has taken place.
mebooksfree.net

Common Tumor Types
Most (≥95%) salivary gland neoplasms are of epithelial origin. 47 The WHO recognizes 11 benign and 22
malignant epithelial subtypes of salivary tumors, which are in turn characterized by marked biologic
heterogeneity. 47 High-grade mucoepidermoid carcinomas (MECs), salivary ducts carcinomas, malignant
mixed tumors, and high-grade adenocarcinomas have the most aggressive clinical course with early
regional and distant metastases. The most common tumors are briefly discussed in the following sections.
Metastatic skin cancer (most frequently SCC) is also an increasing concern, particularly, in elderly or
immunocompromised patients, such as patients with chronic lymphocytic leukemia or organ transplant
recipients. 48
mebooksfree.net

Pleomorphic Adenoma
Pleomorphic adenoma, also known as benign mixed tumor, is the most common salivary gland epithelial
tumor in both adults and children and comprises one-half to two-thirds of all benign salivary gland
tumors. 49 About 80% of pleomorphic adenomas are found in the parotid gland. 49 Tumors are most
common in the fourth to fifth decade. Pleomorphic adenomas are well circumscribed and are grossly
lobular and gray in appearance, although myxoid variants are more gelatinous, whereas cellular variants
are firm and may appear tan-white. This tumor is histologically characterized by epithelial and
connective tissue elements, with stellate and spindle cells interspersed within a myxoid background.
Pleomorphic adenomas are treated by surgical excision and are associated with very low recurrence rates
(0%–5%). 49,50 Incomplete excision is the main risk for recurrence. For parotid tumors, pseudopodia pose a
theoretic risk for recurrence when margins are narrow. Left untreated, up to 15% of pleomorphic
adenomas may undergo malignant transformation into a lesion known as carcinoma ex pleomorphic
adenoma, which is why resection is recommended. 49
mebooksfree.net

Warthin Tumor
Warthin tumor (papillary cystadenoma lymphomatosum) is the second most common tumor of the
parotid gland and is benign. Warthin tumors predominantly occur in males of 50 to 70 years of age, most
frequently smokers, and are the most common bilateral salivary gland tumors (5%–14%). 49 The histologic
appearance of this tumor is characteristic, consisting of papillary cysts and mucoid fluid as well as
nodules of lymphoid tissue. Because of the mitochondrial concentrations in oncocytes, Warthin tumors
do not infrequently demonstrate fluorodeoxyglucose uptake on PET scan, potentially leading to a false-
positive study. 50
mebooksfree.net

Mucoepidermoid Carcinoma
MEC is the most common salivary gland malignancy (about 35% of salivary gland cancers) and consists
of mucin-secreting, intermediate, and epidermoid cells. 43 The histologic grade (low, intermediate, high)
of MEC has prognostic value and dictates the need for adjuvant radiation therapy. Low- and
intermediate-grade tumors often present as asymptomatic slow-growing, solitary masses. High-grade
tumors may progress rapidly and present with symptoms including pain, nerve deficits, and local soft
tissue invasion. Overall survival is 80% to 90% for low- and intermediate-grade tumors, whereas high-
grade tumors have an overall survival of 40% to 50% at 5 years. 43,51 Elective node dissection is often
recommended for high-grade tumors; however, histologic grade is seldom known preoperatively.
mebooksfree.net

Acinic Cell Carcinoma
Acinic cell carcinoma accounts for 8% to 14% of salivary gland cancers. 43,51 The parotid is the most
commonly involved salivary gland and usually presents as a slow-growing solitary mass. Tumor cells
have a granular, metachromatic cytoplasm, resembling that seen in the serous acinar cells of salivary
glands. Acinic cell carcinomas tend to behave indolently. Survival is 97%, 93%, and 89% at 5, 10, and
15 years, respectively. 51
mebooksfree.net

Adenoid Cystic Carcinoma
Adenoid cystic carcinoma (ACC) is the second most common malignancy of the salivary glands after
MEC and exhibits a propensity for perineural invasion. There are three histologic subtypes: cribriform,
tubular, and solid. The cribriform pattern has a classic Swiss cheese appearance with cells arranged in
nests separated by round or oval spaces. The tubular pattern has a glandular architecture, whereas the
solid (or basaloid) pattern has sheets of cells with little or no luminal spaces. 43
ACC shows a slow but relentless progression. Five-year survival is as high as 90%, but 15-year survival is
less than 70% and decreases substantially after this with a 20-year survival of 28%. 43,51 ACCs usually have
an indolent natural history although high-grade transformation with markedly worse prognosis (median
survival of 12–36 months) can occur. 43 The risk for regional spread is low (about 5%–20%), but these
cancers have a propensity for local and distant recurrence even 10 to 15 years after initial treatment. 43
Most commonly, spread is to the lungs, bone, and brain. The development of asymptomatic, slowly
growing pulmonary metastases can often be observed for years.
mebooksfree.net

Malignant Mixed Tumors
Malignant mixed tumors of the salivary glands include carcinoma ex pleomorphic adenoma (the most
common variant), intracapsular carcinoma ex pleomorphic adenoma, metastasizing pleomorphic
adenoma, and carcinosarcoma. 51 Carcinoma ex pleomorphic adenoma presents in a preexisting
pleomorphic adenoma with accelerated growth and new-onset pain and/or neuropathy. Nodal metastasis
may be an early finding. Adjuvant radiation following surgery to the primary site and nodal basins may
improve local control rates, although overall survival is poor (about 40% 5-year survival). 51 Intracapsular
carcinoma ex pleomorphic adenoma shows evidence of malignancy cytologically but is confined within
the capsule of a preexisting pleomorphic adenoma and generally has better prognosis than invasive
variants. Metastasizing pleomorphic adenomas show histologic features of benign pleomorphic adenoma
but present with distant metastases and local recurrences. Treatment involves surgical resection of the
involved sites when possible. Prognosis is favorable despite metastases. Carcinosarcomas are rare and
associated with frequent recurrences, distant metastases, and poor overall survival.
mebooksfree.net

Treatment
Complete surgical excision is curative for benign tumors and malignancies when the tumor is small and
low grade. Larger tumors and those with aggressive histologic type and/or high grade are usually treated
with surgery and adjuvant radiation therapy.
mebooksfree.net

Parotidectomy
A superficial parotidectomy is considered the treatment of choice for benign and most malignant tumors
in the superficial lobe of the gland. 43,49 A less than complete superficial parotidectomy that still removes
the entire tumor with a negative margin is referred to as a partial parotidectomy. Total parotidectomy,
sparing the facial nerve if uninvolved, is indicated for deep lobe tumors and, increasingly, for metastatic
cutaneous malignancy (Figure 37.7). 52 Preoperative weakness or invasion based on imaging may require
one or more branches of the facial nerve to be sacrificed. The nerve may also need to be sacrificed if
preservation would lead to grossly positive margins or tumor spillage. Radical parotidectomy involves
total parotidectomy with facial nerve sacrifice. If adjacent structures such as the skin, mandible, or
temporal bone are involved, an extended radical parotidectomy may be indicated. Mastoidectomy/lateral
temporal bone resection may also be indicated to identify and/or resect the facial nerve proximally if the
tumor abuts the mastoid bone or stylomastoid foramen or invades the nerve. 43
mebooksfree.net

FIGURE 37.7 A total parotidectomy has been performed in which both the superficial and deep lobes of the parotid gland have
been removed. The facial nerve (white arrow) is indicated and can be seen arising from the stylomastoid foramen, above of the
posterior belly of the digastric muscle.
Enucleation, which requires simple removal of the mass, is not indicated for malignant tumors and is
controversial for benign tumors, with some surgeons advocating against it. 43,49 For those who consider
enucleation, resection should include the capsule of the tumor (extracapsular enucleation), and it should
be reserved for benign superficial tumors less than 4 cm in diameter. 49
mebooksfree.net

Submandibular, Sublingual, and Minor Salivary Gland Excision
Benign neoplasms of the submandibular gland are treated with submandibular gland excision. For
malignant lesions, level I lymph nodes and possibly other cervical levels are dissected in continuity.
Sublingual gland malignancies are often managed transorally and may include the floor of mouth
mucosa if it is involved or close to the tumor. Obtaining negative margins in sublingual gland surgery
can be challenging because it is not encapsulated by fascia and may invade the mandible, lingual nerve,
or duct of the submandibular gland. 43 Resection of minor salivary gland tumors depends on their
location. Wide local excision is usually performed with the goal of achieving clear margins of at least
5 mm. Resection of palatal and base of tongue tumors can affect speech, swallowing, and velopharyngeal
competence. 43
mebooksfree.net

Cervical Lymphadenectomy
Known cervical metastases should be treated with cervical lymphadenectomy. In the clinically node-
negative neck, the decision between observation and treatment via elective neck dissection or
prophylactic radiation is made based on the likelihood for occult metastases. Risk factors for nodal spread
include histological evidence of perineural invasion, lymphovascular invasion, and extracapsular spread,
as well as high-grade histologic subtypes. 53,54 The most frequently involved nodal levels primarily
depend on the site of the primary tumor.
mebooksfree.net

Adjuvant Therapy
Unresectable locally advanced tumors with skull base or carotid involvement or those occurring in
patients who are not able to tolerate surgery may be managed with primary radiation therapy.
Undifferentiated and high-grade tumors, advanced-stage tumors, including those with facial nerve and
deep lobe involvement, tumors with lymphatic or vascular invasion, and tumors with positive margins
are usually treated with surgery and adjuvant radiation therapy to prevent locoregional recurrence.
Systemic chemotherapy is considered for patients who have recurrence or metastatic disease who are not
candidates for surgical or radiation treatment. 55 Differing histotypes and heterogeneity within histotypes
make it difficult to standardize systemic treatment. Methotrexate, cisplatin, paclitaxel, epirubicin, and
vinorelbine have been used in advanced salivary gland cancers, although not routinely. 55 Targeted
therapy may also have a role in specific salivary gland malignant subtypes, and research is ongoing.
mebooksfree.net

Questions
1. A 40-year-old man presents with a neck mass that is found to be SCC on FNA biopsy. Subsequent
examination demonstrates that he has a tonsillar primary cancer that is positive for HPV on biopsy.
Which of the following statements are true regarding HPV-positive oropharyngeal cancer?
a. The cancer is contagious.
b. The patient should get an HPV vaccination.
c. The patient’s spouse should get an HPV vaccination.
d. The patient’s children should get HPV vaccinations.
e. This cancer is also frequently related to EBV infection.
2. A 60-year-old woman presents with a 1.5 cm SCC of the right lingual mandibular gingiva and an
upper cervical neck mass. Full-thickness cortical invasion of the tumor into the mandible is observed
on computed tomography (CT) scan. In addition to neck dissection, the most appropriate surgical
treatment is:
a. Wide local excision
b. TORS
c. Transoral laser surgery
d. Marginal mandibulectomy
e. Segmental mandibulectomy
3. A 47-year-old Asian man presents with decreased hearing and a sense of fullness in the right ear of
3 months duration. Otoscopy demonstrates a middle ear effusion. He is otherwise asymptomatic.
What is the next appropriate step in management?
a. Placement of a pressure equalization tube
b. Referral for a hearing aid
c. Trial of an oral penicillin
d. Fiberoptic examination of the nasopharynx
e. Serum blood work for EBV antigens
4. A 40-year-old man presents with a 2 cm mass behind the angle of his right mandible. On
examination, he has weakness of his facial muscles on the side of the tumor. A parotidectomy is
performed, and pathology demonstrates a mixed population of predominantly poorly differentiated
epithelial cells and intermediate cells with occasional mucous-secreting cells and neural invasion.
The most likely diagnosis is:
a. MEC
b. Pleomorphic adenoma
c. Warthin tumor
d. SCC
e. Hemangioma
5. A 55-year-old man presents with a 2.5 cm right lateral oral tongue squamous cell cancer and a
single palpably enlarged jugulodigastric lymph node (clinically staged T2N1M0). In addition to
partial glossectomy, what is the most appropriate treatment for the metastatic lymph node?
a. RND
b. MRND
c. SND of levels I-III and total parotidectomy
d. SND of levels I-IV
e. Observation with possible postoperative radiation depending on the final pathology of the
tongue tumor
mebooksfree.net

1. Answer: d. In recent years, HPV has been recognized as an etiologic factor in oropharyngeal SCC.
Because such cancers have a more favorable prognosis than HPV-negative cancers, testing FNA
biopsies and tumor specimens for HPV is recommended. The cancer cannot be transmitted to
another person. Vaccination has no role in treating patients who are already infected and have no
current role in cancer treatment. Vaccination is not recommended for adults who have already been
sexually active for a number of years. Vaccination is recommended for all adolescents and young
adults (not only children of patients with oropharyngeal SCC), aged 9 to 25, ideally prior to the onset
of sexual activity. The vaccine provides protection against the four strains for HPV most commonly
associated with cervical and oropharyngeal SCC, including HPV-16. EBV is associated with
nasopharyngeal carcinoma in endemic regions and has no known association with HPV-related
oropharyngeal SCC.
2. Answer: e. For transcortical invasion of the mandible, a segmental mandibulectomy, in which a
full-thickness portion of the mandible is excised, is the most appropriate surgical treatment. Marginal
mandibulectomy is reserved for cases in which the cancer stops at the periosteum or does not
penetrate full-thickness through the cortex of the mandible. Wide local excision, TORS, and transoral
laser surgery are not adequate treatment for this lesion. Immediate reconstruction of the mandible
with an osteocutaneous free flap is usually indicated, as is postoperative radiation therapy for this
advanced-stage cancer.
3. Answer: d. A serous middle ear effusion in an adult should raise the suspicion for an NPC causing
Eustachian tube dysfunction. Nasopharyngoscopy with a flexible fiberoptic scope should be
performed as the next step in management. NPC is one of the most common cancers in parts of Asia,
most notably southern China, and is associated with EBV seropositivity. If no masses are seen, it
would be reasonable to try an oral antibiotic but also to continue further workup with an imaging
study (CT or MRI) as well as consider biopsy of the nasopharynx. A pressure equalization tube will
allow drainage of the effusion and aeration of the middle ear, restoring hearing and making a
hearing aid unnecessary.
4. Answer: a. Only about 20% of parotid gland tumors are malignant. Malignant tumors may invade
the facial nerve causing facial paralysis. Malignant tumors may also metastasize to the regional
lymph nodes and to distant sites. MECs are the most common malignancy of the parotid gland.
5. Answer: d. Based on the clinical diagnosis of a metastatic lymph node to the ipsilateral neck, a
cervical lymphadenectomy should be performed. RND includes removal of neck lymph nodes in
levels I to V as well as the SCM, IJV, and SAN.
mebooksfree.net

References
American Cancer Society. Cancer Facts and Figures 2013. Atlanta, GA: American Cancer Society; 2013.
Porceddu, SV, Veness, MJ, Guminski, A. Non-melanoma cutaneous head and neck cancer and Merkel cell carcinoma: current concepts,
advances, and controversies. J Clin Oncol. 2015;33:3338-3345.
Gandini, S, Botteri, E, Iodice, S, et al. Tobacco smoking and cancer: a meta-analysis. Int J Cancer. 2008;122:155-164.
Belcher, R, Hayes, K, Fedewa, S, Chen, AY. Current treatment of head and neck squamous cell cancer. J Surg Oncol. 2014;110:551-574.
Mehanna, H, Oyaleye, O, Licitra, L. Oropharyngeal cancer: is it time to change management according to human papilloma virus status?
Curr Opin Otolaryngol Head Neck Surg. 2012;20:120-124.
Chaturvedi, AK, Engels, EA, Pfeiffer, RM, et al. Human papillomavirus and rising oropharyngeal cancer incidence in the United States. J Clin
Oncol. 2011;29:4294-4301.
Deschler, DG, Richmon, JD, Khariwala, SS, et al. The “new” head and neck cancer patient–Young, nonsmoker, nondrinker, and HPV
positive: evaluation. Otolaryngol Head Neck Surg. 2014;151(3):375-380.
Hayes, DN, Van Waes, C, Seiwert, TY. Genetic landscape of human papillomavirus-associated head and neck cancer and comparison to
tobacco-related tumors. J Clin Oncol. 2015;33:3227-3234.
Mirghani, H, Jung, AC, Fakhry, C. Primary, secondary and tertiary prevention of human papillomavirus-driven head and neck cancers. Eur J
Cancer. 2017;78:105-115.
Chinn, SB, Myers, JN. Oral cavity carcinoma: current management, controversies and future directions. J Clin Oncol. 2015:33;3269-3276.
Lydiatt, WM, Patel, SG, O’Sullivan, B, et al. Head and neck cancers: major changes in the American Joint Committee on Cancer Eighth
Edition Cancer Staging Manual. CA Cancer J Clin. 2017;67:122-137.Significant changes to head and neck cancer staging were introduced in 2017.
The most important changes include the creation of a separate staging algorithm for HPV-associated cancer of the oropharynx; changes to the tumor (T)
categories for oral cavity, skin, and nasopharynx cancer; and the addition of ENE to the lymph node category (N) in most head and neck subsite
classifications.
Civantos, FJ, Zitsch, RP, Schuller, DP, et al. Sentinel lymph node biopsy accurately stages the regional lymph nodes for T1-T2 oral squamous
cell carcinomas: results of a prospective multi-institutional trial. J Clin Oncol. 2008;28:1395-1400.
Bernier, J, Domenge, C, Ozashin, M, et al. Postoperative irradiation with or without concomitant chemotherapy for locally advanced head
and neck cancer. N Engl J Med. 2004;350:1945-1952.
Cooper, JS, Pajak, TF, Forastiere, AA, et al. Postoperative concurrent radiotherapy and chemotherapy for high-risk squamous cell carcinoma
of the head and neck. N Engl J Med. 2004;350:1937-1944.
Cooper, JS, Zhang, Q, Pajak, TF, et al. Long-term follow-up of the RTOG 9501/intergroup phase III trial: postoperative concurrent radiation
therapy and chemotherapy in high-risk squamous cell carcinoma of the head and neck. Int J Radiat Oncol Biol Phys. 2012;84:1198-1205.
Pfister, DG, Spenser, S, Brizel, DM, et al. Head and neck cancers, Version 2.2014. Clinical practice guidelines in oncology. J Natl Compr Cancer
Netw. 2014;12:1454-1487.
Guo, T, Goldenberg, D, Fakhry, C. AHNS Series: do you know your guidelines? Management of head and neck cancer in the era of human
papillomavirus. Head Neck. 2017;39:833-839.
Parsons, JT, Mendenhall, WM, Stringer, SP, et al. Squamous cell carcinoma of the oropharynx: surgery, radiation therapy, or both. Cancer.
2002;94(11):2967-2980.
Holsinger, FC, Ferris, RL. Transoral endoscopic head and neck surgery and its role within the multidisciplinary treatment paradigm of
oropharynx cancer: robotics, lasers, and clinical trials. J Clin Oncol. 2015;33:3285-3292.
Lee, AW, Ma, BB, Ng, WT, et al. Management of nasopharyngeal carcinoma: current practice and future perspective. J Clin Oncol.
2015;33:3356-3364.
Gooi, Z, Richmon, J, Agarwal, N. AHNS series: do you know your guidelines? Principles of treatment for nasopharyngeal cancer a review of
the national comprehensive cancer network guidelines. Head Neck. 2017:39;201-205.
Dziegielewski, PT, Kang, SY, Ozer, E. Transoral robotic surgery (TORS) for laryngeal and hypopharyngeal cancer. J Surg Oncol. 2015;112:702-
706.
Department of Veterans Affairs Laryngeal Cancer Study Group , Wolf, GT, Fisher, SG, et al. Induction chemotherapy plus radiation
compared with surgery plus radiation in patients with advanced laryngeal cancer. N Engl J Med. 1991;324:1685-1690.This landmark study
compared induction chemotherapy with definitive radiation therapy with conventional laryngectomy and postoperative radiation for patients with
laryngeal cancer. Surgical salvage was performed for chemoradiotherapy-treated patients who recurred locally. Using this strategy, they reported a high
rate of laryngeal preservation without compromising overall survival. This study changed the treatment paradigm for laryngeal cancer at many centers
throughout the country and across the world.
Forastiere, AA, Zhang, Q, Weber, RS, et al. Long-term results of RTOG 91-11: a comparison of three nonsurgical treatment strategies to
preserve the larynx in patients with locally advanced larynx cancer. J Clin Oncol. 2013;31:845-852.
Forastiere, AA, Weber, RS, Trotti, A. Organ preservation for advanced larynx cancer: issues and outcomes. J Clin Oncol. 2015;33:3262-3268.
Chen, AY, Halpern, M. Factors predictive of survival in advanced laryngeal cancer. Arch Otolaryngol Head Neck Surg. 2007;133:1270-1276.
Gourin, CG, Conger, BT, Sheils, C, et al. The effect of treatment on survival in patients with advanced laryngeal carcinoma. Laryngoscope.
2009;119:1312-1317.
Galloway, TJ, Ridge, JA. Management of squamous cancer metastatic to the cervical nodes with an unknown primary site. J Clin Oncol.
mebooksfree.net

2015;33:3328-3337.
Byrd, JK, Smith, KJ, de Almeida, JR, et al. Transoral robotic surgery and the unknown primary: a cost-effectiveness analysis. Otolaryngol Head
Neck Surg. 2014;150(6):976-982.
Miller, MC, Goldenberg, D. AHNS series: do you know your guidelines? Principles of surgery for head and neck cancer a review of the
National Comprehensive Cancer Network guidelines. Head Neck. 2017;39:791-796.
Maxwell, JH, Thompson, LD, Brandwein-Gensler, MS, et al. Early oral tongue squamous cell carcinoma: sampling of margins from tumor
bed and worse local control. JAMA Otolarygol Head Neck Surg. 2015;141(12):1104-1110.
Mukhija, V, Gupta, S, Jacobson, AS, et al. Selective neck dissection following adjuvant therapy for advanced head and neck cancer. Head
Neck. 2009;1(2):183-188.
Cheraghlou, S, Otremba, M, Kuo Yu, P, et al. Prognostic value of lymph node yield and density in head and neck malignancies. Otolaryngol
Head Neck Surg. 2018;158(6):1016-1023.
Schilling, C, Stoeckli, SJ, Haerle, SK, et al. Sentinel European Node Trial (SENT): 3-year results of sentinel node biopsy in oral cancer. Eur J
Cancer. 2015;51(18):2777-2784.
Gooi, Z, Fakhry, C, Goldenberg, D, et al. AHNS series: do you know your guidelines? Principles of radiation therapy for head and neck
cancer a review of the National Comprehensive Cancer Network guidelines. Head Neck. 2016;38:987-992.
Chen, WC, Hwang, TZ, Wang, WH, et al. Comparison between conventional and intensity modulated post-operative radiotherapy for stage
III and IV oral cavity cancer in terms of treatment results and toxicity. Oral Oncol. 2009;45:505-510.There has been a dramatic rise in
oropharyngeal SCC in recent years because of HPV infection. Patients with HPV-related oropharynx cancers are younger and lack traditional risk
factors such as tobacco and alcohol use. Biologically, these HPV-related oropharyngeal cancers behave differently, necessitating new treatment
algorithms and staging systems.
Van de Water, TA, Bijl, HP, Schilstra, C, et al. The potential benefit of radiotherapy with protons in head and neck cancer with respect to
normal tissue sparing: a systematic review of literature. Oncologist. 2011;16:366-377.
Bonner, JA, Harari, PM, Giralt, J, et al. Radiotherapy plus cetuximab for squamous-cell carcinoma of the head and neck. N Engl J Med.
2006;354:567-578.
Buglione, M, Maddalo, M, Corvò, R, et al. Subgroup analysis according to human papillomavirus status and tumor site of a randomized
phase II trial comparing cetuximab and cisplatin combined with radiation therapy for locally advanced head and neck cancer. Int J Radiat
Oncol Biol Phys. 2017;97(3):462-472.
Magrini, SM, Buglione, M, Corvò, R, et al. Cetuximab and radiotherapy versus cisplatin and radiotherapy for locally advanced head and
neck cancer: a randomized phase II trial. J Clin Oncol. 2015;34:427-435.
Seiwert, TY, Burtness, B, Mehra, R, et al. Safety and clinical activity of pembrolizumab for treatment of recurrent or metastatic squamous cell
carcinoma of the head and neck (KEYNOTE-012): an open-label, multi-centre, phase 1b trial. Lancet Oncol. 2016;17:956-965.
Ferris, RL, Blumenschein, G Jr, Fayette, J, et al. Nivolumab for recurrent squamous-cell carcinoma of the head and neck. N Engl J Med.
2016;375:1856-1867.
Rodriguez, CP, Parvathaneni, U, Méndez, E, Martina, RG. Salivary gland malignancies. Hematol Oncol Clin North Am. 2015;29:1145-1157.
Dercle, L, Hartl, D, Rozenblum-Beddok, L, et al. Diagnostic and prognostic value of 18F-FDG PET, CT, and MRI in perineural spread of head
and neck malignancies. Eur Radiol. 2018;28(4):1761-1770.
Siewert, B, Kruskal, JB, Kelly, D, et al. Utility and safety of ultrasound-guided fine-needle aspiration of salivary gland masses including a
cytologist’s review. J Ultrasound Med. 2004;23(6):777-783.
Seethala, RR, LiVolsi, VA, Baloch, ZW. Relative accuracy of fine-needle aspiration and frozen section in the diagnosis of lesions of the parotid
gland. Head Neck. 2005;27(3):217-223.Use of FNA and frozen section in the diagnosis of salivary gland lesions are a subject of debate because of less
than perfect accuracy. FNA was found to have a sensitivity of 86% and specificity of 92%. Frozen section was found to have a sensitivity of 77% and a
specificity of 100%. The authors suggest that frozen section may be useful if FNA is nondiagnositc and may confirm or refute malignancy in some
cases.
Seethala, RR, Stenman, G. Update from the 4th edition of the World Health Organization classification of head and neck tumors: tumors of
the salivary gland. Head Neck Pathol. 2017;11:55-67.
O’Brien, CJ. The parotid as a metastatic basin for skin cancer. Arch Otolaryngol Head Neck Surg. 2005;131(7):551-555.
Zhan, KY, Khaja, SF, Flack, AB, et al. Benign parotid tumors. Otolaryngol Clin North Am. 2016;49:327-342.
Rassekh, CH, Cost, JL, Hogg, JP, et al. Positron emission tomography in Warthin’s tumor mimicking malignancy impacts the evaluation of
head and neck patients. Am J Otolaryngol. 2015;36(2):259-263.
Guzzo, M, Locati, LD, Prott, FJ, et al. Major and minor salivary gland tumors. Crit Rev Oncol Hematol. 2010;74:134-148.
Thom, JJ, Moore, EJ, Price, DL, et al. The role of total parotidectomy for metastatic cutaneous squamous cell carcinoma and malignant
melanoma. JAMA Otolaryngol Head Neck Surg. 2014;140(6):548-554.
Breen, B, Rahimi, S, Brennan. Current management of the neck in salivary gland carcinomas. J Oral Pathol Med. 2017;46:161-166.
Wang, YL, Lin, DS, Gan, HL, et al. Predictive index for lymph node management of major salivary gland cancer. Laryngoscope. 2012;122;1497-
1506.This study examines predictive factors for spread of salivary gland cancer to regional lymph nodes. Tumor- and patient-related factors were used
to determine the relative risk for lymph node metastases to guide the indications for elective neck dissection.
Laurie, SA, Licitra, L. Systemic therapy in the palliative management of advanced salivary gland cancers. J Clin Oncol. 2008;24:2673-2678.
mebooksfree.net

C H A P T E R 3 8
mebooksfree.net

Reconstruction of the Scalp, Forehead, Calvarium,
Skull Base, and Midface
Alexander F. Mericli and Jesse C. Selber, and Matthew M. Hanasono
Key Points
Locoregional or free flaps are usually required for scalp defects that include the pericranium.
Unlike other head and neck sites, tissue expansion may play a role in reconstruction of the scalp.
Resection of skull base tumors may be associated with significant complications including
cerebrospinal fluid leak and cranial nerve deficits.
The location of the skull base tumor determines the approach to resection and dictates the
reconstructive needs.
Maxillary defects are usually complex; prosthetics, soft tissue flaps, and/or bone grafts and flaps may
play a role in reconstruction.
Defects involving the scalp, forehead, calvarium, skull base, and maxilla are among the most challenging
reconstructions in our specialty. Although these structures are adjacent anatomically, their reconstructive
requirements are vastly different given the multiple specialized functions located within the head and
neck. The techniques employed to restore these anatomic regions are complex, nuanced, and frequently
necessitate microsurgery. Furthermore, defects involving the calvarium, skull base, and maxilla are
especially challenging because of the potential for major, life-threatening complications that may occur
should the reconstruction fail, such as brain exposure and neurologic injury, blindness, cerebrospinal
fluid (CSF) leak, meningitis, and osteomyelitis.
mebooksfree.net

Scalp, Forehead, and Calvarium
Scalp and forehead tissue is intrinsically inelastic, limiting the application of primary closure and local
flaps. Skin grafts are possible when the pericranium is intact, and a variety of local flaps can be designed.
There are only three regional flaps (pericranium, temporoparietal fascia, and temporalis muscle), all of
which have a limited arc of rotation thereby minimizing their utility; therefore, microvascular free tissue
transfer is commonly required for durable reconstruction in this area of the body for sizable defects.
Calvarial reconstruction can include alloplastic materials, customized implants, and bone grafting,
depending on the circumstances.
mebooksfree.net

Anatomy
The frontalis muscle overlies the frontal bone and is connected to the occipitalis muscle posteriorly,
through the galea aponeurotica. The blood supply of the forehead and scalp is robust and consists of the
paired supraorbital, supratrochlear, superficial temporal (ST), posterior auricular, and occipital vessels.
The sensory nerves are also paired and include the supraorbital, supratrochlear, zygomaticotemporal,
auriculotemporal, lesser occipital, and greater occipital nerves. The most clinically significant motor nerve
is the temporal branch of the facial nerve, which innervates the frontalis muscle. This branch is located on
the deep surface of the temporoparietal fascia and follows a course approximated by a line extending
from 0.5 cm inferior to the external auditory meatus to a point 1.5 cm superior to the lateral eyebrow.
Dissection in this area is occasionally needed to access the zygomatic arch for reduction and internal
fixation or to raise a temporalis muscle flap. To avoid injury to this important nerve, dissection is
performed in a plane deep to the superficial layer of the deep temporal fascia. The calvarium is covered
by thick periosteum oftentimes called pericranium, which can be utilized as a local flap. Structurally, the
calvarium is comprised of three layers: an outer table, a diploic space, and an inner table.
mebooksfree.net

Forehead and Scalp Reconstruction
Nonmicrosurgical Techniques
The skin of the scalp is among the thickest in the body, measuring 3 to 8 mm. This thickness, as well as
the fibrous galea aponeurotica, limits the pliability of the scalp. Although primary closure with adjacent
hair-bearing tissue is the preferred wound closure technique in the appropriate scenario, this approach is
typically limited to defects no greater than 3 cm in diameter. Tension should be avoided to prevent skin
dehiscence or alopecia. There are several techniques that can be employed to reduce tension when
reconstructing a scalp defect via primary repair or adjacent tissue rearrangement. First, the resection can
be designed so that the closure is oriented perpendicular to the relaxed skin tension lines; this tends to be
in a sagittal direction on the scalp and in a transverse direction on the forehead. Second, wide
undermining in the subgaleal layer along the circumference of the defect can reduce tension. Finally,
galeal scoring is an adjunctive technique that can increase scalp pliability and reduce closure tension. The
scores should be designed in parallel with the leading edge of the flap, be spaced no closer than 1 cm
apart, and only divide the galea. Scores deeper than the galea will disrupt the random pattern blood
supply of the scalp. Each galeal incision increases the length of the scalp 1.67 mm; therefore, multiple
incisions can substantially minimize tension and maximize pliability. 1
If the scalp defect is too wide to permit primary closure and the underlying calvarium is not exposed, the
wound can be closed with a split- or full-thickness skin graft. Alternatively, if the calvarium is exposed,
burring the outer table with entry into the vascular diploic space can facilitate skin graft adherence. This
can be performed immediately or with an intermediate stage using a dermal substitute; however, this
often results in an unstable skin graft and is not recommended as a long-term solution or in the context of
radiation. In any situation, once healed, the graft will not bear hair. Additionally, because of the
difference in thickness between the native scalp and a skin graft, a noticeable contour deformity will be
present.
One of the central tenets of reconstructive surgery—replacing like with like—is evident in the use of local
flaps for scalp reconstruction. This technique will maintain the thickness of the scalp as well as the ability
to bear hair. In situations where the calvarium is exposed at the base of the wound, reconstruction with
vascularized tissue, such as a local flap, is required. Most local flaps are designed using the rotation-
advancement principle and should be oriented to recruit tissue from areas of the scalp with laxity, such as
the parietal and temporal regions. The meticulous plastic surgeon will attempt to match hair follicle
direction with the flap and will also bevel the incision parallel to the angle of the hair follicles to minimize
scar alopecia. In smaller defects, the local flap donor site can be closed primarily (Figure 38.1); however,
reconstruction of larger defects may require elevating the local flap in the subgaleal plane and
maintaining the pericranium so that the donor site can then be closed with a skin graft (back grafting).
The skin graft can then be serially excised secondarily or the remaining scalp tissue expanded and the
skin graft excised, to improve appearance. Larger configurations of multiple flaps, such as the Orticochea
flap, are well described but unpopular because of the high rate of partial flap necrosis. 2
mebooksfree.net

FIGURE 38.1 A. A 4-cm diameter defect of the vertex scalp reconstructed with bilateral rotation-advancement flaps. B. The
flaps are advanced and the donor site is closed primarily.
Unlike the scalp, additional attention is required when addressing a forehead wound so that the closure
does not distort the brow or anterior hairline. This is often at odds with the direction of tissue laxity along
the forehead; however, brow or hairline symmetry must never be compromised for primary closure; a
local flap or graft, or even a free flap, is preferred. Because the forehead is a visible area as compared with
the hair-bearing scalp, color match and incision orientation require careful planning. The aesthetic
subunit principle should be followed to make the reconstruction as inconspicuous as possible. 3
Whenever possible, skin grafts should be harvested from a location above the clavicles to achieve a good
color match. Incisions should be designed within the transverse forehead rhytids or along the anterior
hairline or browline (Figure 38.2). For limited defect size, healing by secondary intention can have a better
cosmetic outcome than skin grafting, as can be frequently seen in the treatment of donor defects for
forehead flaps. 4 When operating anywhere around the forehead or brow, care should be taken to avoid
injury to the temporal branch of the facial nerve. A variety of local flaps have been described for
reconstruction of small forehead wounds, such as in the setting of Mohs surgery; these techniques are
addressed elsewhere in this book.
mebooksfree.net

FIGURE 38.2 A,B. 5 cm defect after resection of forehead invasive melanoma. Delayed reconstruction performed after
negative final margins. C. Scalp advancement flap to recreate anterior hairline, forehead rotation flap with W-plasty closure of
dogear to limit the inferior extent of the scar. D. Retroauricular full-thickness skin graft used to close donor site along temporal
scalp/forehead.
Tissue expansion is useful in reconstructing scalp and forehead wounds due to trauma, burns, or
congenital lesions. It is less germane in the oncologic setting when there is typically an urgent need for
resection, thus eliminating the possibility of pre-expansion prior to resection and reconstruction.
Additionally, a history of radiation therapy or the anticipated need for adjuvant radiation precludes the
use of tissue expansion, as the associated complication rate is prohibitively high. 5 When appropriately
implemented, tissue expansion is a powerful technique in scalp reconstruction, permitting reconstruction
of an area up to 50% of the total surface area of the scalp with hair-bearing tissue of a similar thickness.
Expanders come in a variety of shapes and sizes, allowing the surgeon to match the desired vector of
expansion. Typically, the expander is placed in the subgaleal plane deep to the healthy scalp. The incision
used to place the expander should be designed in the area of scalp that will be excised and should be
oriented perpendicular to the axis of expansion to help prevent incisional dehiscence and exposure of the
device. In large defects, multiple expanders can be placed; ports are typically remote.
Regional flaps are, in general, infrequently used in scalp reconstruction because of the limited number of
donor flaps in close proximity. The temporoparietal fascial flap and temporalis muscle flap can be used
for defects within or adjacent to the temporal area or lateral forehead and are usually combined with a
skin graft. The trapezius muscle can be designed as either a muscle or myocutaneous flap and can be
used to reconstruct the occipital scalp.
mebooksfree.net

Microsurgical Techniques
Free flap reconstruction of the scalp is necessary when local options or skin grafting are inadequate. This
may be because of defect size and depth, the anticipated need for radiation therapy, prior radiation
therapy, or extensive scarring from past surgeries. Preoperatively, a thoughtful reconstructive plan
should be devised that includes selection of an appropriate flap and options for recipient vessels.
Recipient vessels should have a similar caliber as those of the flap and should be in close proximity to the
defect. For the scalp, the ST vessels are the typical first-line option. 6 Using the ST vessels is associated
with a high flap success rate (96%) and compatibility with a variety of free flaps and defects. 6 The
patency of these vessels should be evaluated preoperatively by gently palpating the preauricular area
bilaterally to feel a pulse; alternatively, a pencil Doppler ultrasound can be used.
There are several technical points that must be understood to achieve success with the ST vessels. The ST
artery and vein are located anterior to the ear and represent the distal extent of the external carotid
system (Figure 38.3). Ideally, the anastomosis should be performed at the level of the tragal notch where
the vessels emerge from the parotid. This portion of the artery has the greatest diameter and least
tortuosity. The artery tends to be more superficial and posterior, whereas the vein may exist in a slightly
deeper plane and more anterior. The vein is notoriously thin walled and prone to inadvertent twisting, so
special care must be observed. Because of these anatomical nuances, many find it helpful to perform the
majority of this recipient vessel dissection under the operating microscope or high-power loupe
magnification.
mebooksfree.net

FIGURE 38.3 A. Large scalp defect reconstructed with free latissimus dorsi muscle flap and split-thickness skin graft.
Microvascular anastomoses were performed to the superficial temporal artery and vein. B. Note the significant atrophy of the
bulky muscle flap and its improved contour after radiation therapy 10 months after surgery. C. The superficial temporal artery
and vein are commonly used as recipient vessels in microvascular reconstruction of the scalp. The anastomosis should be
performed at the level of the tragal notch, where the vessels emerge from within the parotid gland. D. When insetting a free
muscle flap for scalp reconstruction, the native scalp should be undermined circumferentially so that the flap can be inset in a
vest-over-pants fashion.
If the ST vessels are not available or insufficient, the neck provides a multitude of options: facial, lingual,
superior thyroid, etc. The pedicle length required to travel from the neck to the scalp almost always
necessitates the use of a vein graft. Special care must be taken to avoid kinking or twisting the vein graft
or pedicle, particularly with head turning. The vein grafts should be placed beneath a widely
undermined cutaneous tunnel, and the patient should be prevented from wearing eyeglasses during the
immediate postoperative period to avoid compression.
Many flaps have been described for use in microsurgical scalp reconstruction 6–8 (Table 38.1). The
incidence of cutaneous malignancies located on the scalp is higher in elderly patients and continues to
mebooksfree.net

rise after age 65 years. Therefore, it is not uncommon for septua- and octogenarians (or older) to require
extensive scalp resections. It is important to emphasize that age is not a contraindication to microsurgical
scalp reconstruction, as has been demonstrated in several studies. 9,10 Muscle flaps covered with a skin
graft as well as fasciocutaneous flaps have been repeatedly and successfully used for scalp reconstruction.
Muscle flaps are bulky initially, but will atrophy over time; this effect is accelerated if postoperative
radiation is given (see Figure 38.3). Once the flap atrophies, it contours nicely along the underlying skull.
When insetting a muscle flap, it is prudent to inset the flap in a vest-over-pants fashion, with the flap
tucked under the remaining scalp so that when the flap atrophies, it is less likely to pull away from the
native scalp and cause exposure of the skull (see Figure 38.3). Flaps with a skin paddle are thought to be
more durable and may be preferred in situations where the flap is covering a cranioplasty. The
disadvantage to a skin paddle is that it may require a secondary debulking procedure to improve the
contour, as these flaps are less likely to atrophy.
TABLE 38.1
Common Flaps Used for microsurgical Scalp Reconstruction
Flap
Type
Size
Pedicle
Notes
Latissimus dorsi
Muscle or
myocutaneous
25 × 35 cm
Thoracodorsal
Can be combined with the serratus muscle to make a
chimeric flap able to resurface a larger area
Insertion area of the muscle overlying the pedicle
should be transected obliquely to allow for a better, less
bulky contour
Serratus anterior
Muscle
10 × 15 cm
Thoracodorsal or
lateral thoracic
Only inferior 3 or 4 slips are harvested to prevent
winging of the scapula
Pedicle is on anterior surface of the muscle; care must
be taken during exposure
Rectus
abdominis
Muscle or
myocutaneous
25 × 6 cm
Deep inferior
epigastric
Deep inferior
epigastric
perforator
Fasciocutaneous
perforator
40 × 15 cm
Deep inferior
epigastric
Large surface area
Bulky flap limited by patient’s habitus
Potentially long pedicle
Vastus lateralis
Muscle
20 × 10 cm
Descending branch of
lateral femoral
circumflex
Small muscle flap with limited donor site morbidity
May be useful when use of a fasciocutaneous ALT flap
is precluded by habitus
Anterolateral
thigh (ALT)
Fasciocutaneous
or
myocutaneous
20 × 9 cm
Descending branch of
lateral femoral
circumflex
Radial forearm
Fasciocutaneous
15 × 8 cm
Radial artery
Small thin flap for modest defects
Long pedicle
Similar thickness as native scalp
Omentum
Visceral adipose
tissue
25 × 35 cm
Gastroepiploic
Potential for significant donor site morbidity
Can be harvested robotically or laparoscopically
Usually atrophies significantly over time
Variable skin graft take
mebooksfree.net

Reconstruction of the Calvarium
Resection of primary bone malignancies, bone metastases, osteoradionecrosis, traumatic defects, or soft
tissue tumors of the scalp that involve the underlying calvarium can result in a bony defect. The goals of
calvarial reconstruction are both functional and cosmetic, protecting the central nervous system as well as
restoring the normal contour of the skull. Calvarial reconstruction is usually recommended for any full-
thickness defect greater than 6 cm2. 11
mebooksfree.net

Alloplastic Materials
Calvarial reconstruction is most commonly performed using alloplastic materials (Table 38.2). Alloplastic
materials are abundant in supply and have no donor site morbidity, but may be more prone to infection
than autologous bone grafts, which may preclude their use in infected or irradiated fields. The ideal
alloplastic implant is compatible with surrounding bone and soft tissue, resistant to infection, strong,
easily shaped, and remains stable over time. Numerous materials have been described, including
titanium mesh, polymethyl methacrylate, porous polyethylene, calcium phosphate cement, and
polyetheretherketone (PEEK) 12–14 (Figure 38.4). Many biomaterials can be produced using computer-
aided design/computer-aided modeling (CAD/CAM) techniques to exactly match the dimensions of the
existing or anticipated cranial defect. CAD/CAM technology is available for titanium, porous
polyethylene, and PEEK implants. 14,15 Lee and colleagues evaluated their extensive experience in
oncologic calvarial reconstructions and identified prior surgery, infection, radiation, and concurrent free
tissue transfer to be associated with complications. 12 The type of alloplastic material used was not found
to be an independent risk factor for complications on multivariate analysis.
TABLE 38.2
Alloplastic Materials Used for Calvarial Reconstruction
Material
Structure
Structural
Integrity
Infection
Risk
Intraoperative
Contouring
CAD/CAM
Advantages
Disadvantages
Titanium mesh
Metal alloy
Strong
Low
Yes
Yes
Readily available
Imaging artifact
Polymethyl
methacrylate
Acrylic-
based resin
Moderate;
can be
brittle
Moderate;
becomes
encapsulated
Yes
No
Easily moldable
intraoperatively
Can
be
combined
with
titanium
plate
for
increased
strength
Cures
exothermi
reaction
can
da
surroundin
tissue
Infection r
Porous polyethylene
Porous
hydrocarbon
Strong
Low; pores
encourage
tissue
ingrowth
Yes
Yes
Pores
mitigate
infection risk
Pores
removal
difficult
Calcium phosphate
Bone cement
putty
Weak
High late
infection risk
Yes; moldable
No
Best for small
defects
Osteoconductive
Brittle
Use limit
smaller de
Polyetheretherketone
Aromatic
polymer
Strong
Moderate-
becomes
encapsulated
Minimal;
edges can be
burred
Yes
Radiolucent
Becomes
encapsulat
Little abil
adjust
intraopera
mebooksfree.net

FIGURE 38.4 A. Titanium mesh calvarial reconstruction. B. Polyetheretherketone cranioplasty.
mebooksfree.net

Autologous Techniques
Autologous reconstruction of the calvarium involves the use of either vascularized or nonvascularized
bone. Several options have been described, including split calvarial or iliac grafts, vascularized or
nonvascularized rib, and vascularized fibula. 16–18
Split calvarial grafts should be harvested from the parietal bone where the skull is the thickest. The graft
site should not extend any further medially than 1.5 cm lateral to midline, to avoid inadvertent injury to
the sagittal sinus. Calvarial bone can be harvested using an in situ technique or an extracranial approach.
In the in situ technique, a trough is burred around the outline of the graft until the diploic space is
reached. A saw or osteotome is then used to remove the outer table of the skull as a graft. The advantage
of this technique is that it avoids accessing the intracranial space. Disadvantages include the creation of a
depression contour deformity along the skull; additionally, the size of the graft is limited. In the
extracranial approach, a craniotomy is performed and a full-thickness section of the calvarium is
removed. On the back table, a saw or osteotome is then used to separate the inner and outer tables
through the diploic space. The inner table is then plated back onto the donor site, flush with the adjacent
calvarium, to avoid a contour depression. The external table is then used as a graft. Because of the need
for a craniotomy, the extracranial technique is usually performed by a neurosurgeon.
Compared with calvarial bone grafts, larger defects can be repaired using rib. The seventh and eighth ribs
are most commonly used; in men, rib graft is harvested through an incision directly over the rib, whereas
in women, an inframammary fold incision is better camouflaged. No more than two or three ribs can be
harvested, to maintain chest wall stability. Ribs are harvested in a subperiosteal plane to avoid pleural
injury. Grafts can be shaped with a rib bender and plated to the calvarium. Gaps between the rib grafts
can be filled with either particulate cadaveric allograft bone, calcium phosphate bone cement, or
hydroxyapatite putty.
Vascularized bone flaps are useful for smaller calvarial defects within a hostile wound bed. Wounds
exposed to radiation or chronic infection are particularly good candidates. A serratus anterior or chimeric
latissimus-serratus anterior flap can be designed with vascularized rib and covered with a skin graft,
thereby reconstructing an osseous and soft tissue defect with a single flap.
19 A chimeric
scapular/parascapular flap has also been described for this purpose, but with using a segment of scapula
bone for calvarial defect. 20 The ever-versatile free fibula flap has also been described for calvarial
reconstruction—specifically for replacing the anterior table of the frontal sinus in the setting of a chronic
mucocele. 18
mebooksfree.net

Management of the Infected Cranioplasty
Because of their robust vascularity, infection is fortunately uncommon in the scalp and calvarium.
Infection of alloplastic cranioplasties and cranial bone flaps following craniotomy can be clinically
challenging and place the patient at risk for meningitis or brain abscess. If there are signs of infection, the
patient should first be treated with empiric, broad-spectrum intravenous antibiotics. If there is no
significant clinical improvement, the patient may need to have the cranioplasty or bone flap explanted.
This is a serious complication because a redo cranioplasty cannot be performed until the infection has
fully cleared. During this period of time, the scalp will shrink in size and conform to the concave contour
of the bony defect. Furthermore, if treatment of the infected cranioplasty requires debridement of
devitalized scalp, there may be a significant soft tissue deficiency.
If after removal of the cranioplasty and debridement, the scalp cannot be closed primarily, the patient will
require a soft tissue flap. In this situation, a well-vascularized free myocutaneous flap or muscle flap with
skin graft is preferable. It is important for the patient to understand that he or she will have no skull in
this area and will be vulnerable to intracranial injury during this period of time. Free flaps are
purposefully made redundant for later placement of a convex cranioplasty. After the infection has been
adequately treated, an elective cranioplasty can be performed by elevating the free flap and scalp off of
the dura with the help of a neurosurgeon.
mebooksfree.net

The Role of Composite Tissue Allograft Transplantation in Reconstruction of the
Scalp and Calvarium
A recent addition to the reconstructive ladder in the treatment of scalp and calvarial wounds is
vascularized composite allograft (VCA) transplantation. 21,22 Although not commonly employed,
situations do exist in which VCA is a reasonable reconstructive option. One such scenario includes
transplant patients with large, invasive, and diffuse malignancies of the scalp. These are more common
than one may think, as invasive skin cancers of the head and neck occur frequently in the transplant
population. For these patients, a transplant that includes scalp and calvarium can be based on ST vessels
without the addition of alloplastic materials or donor site defects. A recent case involved a patient who
was a previous recipient of a kidney-pancreas transplant, who was in need of a second transplant (Figure
38.5). As a result of his longstanding immunosuppression, he developed a leiomyosarcoma of the scalp,
treated with excision and radiation therapy. He then developed an unstable scalp wound with
underlying osteoradionecrosis of the skull; this chronic wound precluded him from being included on the
transplant list for a repeat kidney-pancreas transplant. A single organ donor was acquired for
simultaneous transplantation of the kidney, pancreas, skull, and scalp, thereby addressing all needs in
one operation. VCA is an emerging field and can be a useful solution to complex problems in select
transplant patients with extensive, composite head and neck defects.
FIGURE 38.5 A–C. Vascular composite allograft transplant including scalp and skull. Donor specimen was harvested en block
and supplied by the bilateral superficial temporal vessels. D. One-year postoperative result.
mebooksfree.net

Skull Base Reconstruction
Except for lesions removed via an endoscopic approach, reconstruction may play a major role in the
treatment of skull base tumors because of the substantial anatomic and functional deficits that can result
following resection of various craniofacial structures. Although historically, skull base resections have
been associated with poor outcomes, advances in reconstruction, which minimize complications, loss of
function, and disfigurement, concomitant with advances in oncologic treatment, have substantially
decreased the morbidity resulting from the treatment of these tumors.
mebooksfree.net

Anatomy
The Irish classification system, based on the relationship of the tumor to the anterior, middle, and
posterior cranial fossae, is most useful for describing the clinical anatomy of the resection and associated
reconstructive options 23 (Figure 38.6). These resections involve removal of skull base bone with or
without the removal of the underlying dura.

mebooksfree.net

FIGURE 38.6 Skull base regions.
(Adapted from Irish, JC, Gullane, PJ, Gentili, F, et al. Tumors of the skull base: outcome and survival analysis of 77 cases. Head Neck. 1994;16(1):3-10.
Copyright © 1994 Wiley Periodicals, Inc., A Wiley Company. Reprinted by permission of John Wiley & Sons, Inc.)
Region I involves the anterior skull base; these tumors typically arise from in and around the orbits, nose,
sinuses, or cribriform plate. Region II involves the lateral skull base; these tumors arise from the
infratemporal or pterygopalatine fossae extending to the middle cranial fossa and can include
nasopharyngeal carcinoma, juvenile nasopharyngeal angiofibroma, and locally advanced parotid tumors.
Region III involves the temporal bone and posterior cranial fossa; these tumors typically arise from the
ear, parotid, or temporal bone.
mebooksfree.net

Reconstructive Approach
Cranial nerve deficits should be anticipated based on the location of the tumor and discussed with the
patient preoperatively. Possible functional deficits after skull base surgery may include facial nerve
paralysis, dysphagia, and dysarthria due to hypoglossal nerve palsy, and/or shoulder asymmetry due to
transection of the spinal accessory nerve. If the facial nerve is removed with a portion of the tumor, then
consideration should be given to the reconstruction of the nerve gap with an interposition cable graft.
Static and dynamic procedures for facial nerve paralysis should be considered. A detailed discussion of
treatment for facial nerve paralysis is addressed elsewhere in this book.
Given the paucity of local flap options in this anatomic area, free tissue transfer is frequently required for
reconstruction. If the ST vessels are no longer present because of previous use, radiation-related changes,
or resection, then the neck provides a multitude of recipient options. Unfortunately, the pedicle length
required to reach the neck from the skull base may necessitate vein grafts; this should be recognized
preoperatively and incorporated into the reconstructive plan prospectively.
The need or desire for an orbital or auricular prosthesis should be discussed preoperatively because this
may influence flap design and reconstructive staging. Facial prostheses are created by an anaplastologist
and can be secured with adhesive or through the use of osseointegrated anchors. Additionally, if the skull
base resection includes removal of the middle ear components, an otologist should be involved
preoperatively for placement of a bone-anchored hearing aid (BAHA). Osseointegrated implants and
BAHAs have a higher failure rate when placed into irradiated bone; therefore, if radiation is anticipated,
consideration should be given to immediate placement of the device.
Because use of either a regional or free flap may limit the utility of physical examination to detect local
recurrence, serial imaging is mandatory for disease surveillance and should be incorporated into the
survivorship plan.
mebooksfree.net

Region I
Midline region I tumors are usually resected with an anterior craniofacial approach, resulting in
communication of the nasal cavity with the intracranial space. If the defect is small and limited to the
upper nasal cavity, the intracranial space can be separated from the sinuses with a pedicled pericranial
flap or galea frontalis flap, both of which derive their blood supply from the supratrochlear and
supraorbital vessels. In situations where these blood vessels have already been transected, or in larger
defects involving the external nose, forehead, and/or orbit, a free flap may be necessary (Figure 38.7). If
there is no skin defect and the flap is only needed to separate the intracranial space, then the free flap
may be buried and monitored with an implantable Doppler probe. The rectus abdominis, vastus lateralis,
and serratus anterior muscle flaps are good options in this situation.
FIGURE 38.7 A. Zone I skull base defect following a left extended orbital exenteration resulting in communication with the
anterior cranial fossa. B. Reconstruction with an anterolateral thigh myocutaneous free flap. The muscle (vastus lateralis) is
placed against the dural patch to help prevent cerebrospinal fluid leaks and is also used to obliterate possible communication
with the nasal cavity and paranasal sinuses. C. Postoperative result.
Lateral region I defects frequently involve orbital exenteration. If the resection spares the medial and
inferior walls of the orbit, it is well suited for the eventual use of a prosthesis. To accommodate a
prosthesis, the orbit must be resurfaced with a thin, pliable, well-vascularized tissue that will maintain
the concave shape of the cavity. This can be achieved with a free radial forearm flap or pedicled
temporalis muscle or temporoparietal fascia flap with a skin graft. If the orbital exenteration results in
communication with the sinuses or nasal cavity, then a bulkier myocutaneous free flap is preferred. The
anterolateral thigh (ALT) and rectus abdominis myocutaneous (RAM) flaps are highly customizable and
allow for the design of flap with a variable amount of muscle, tailored to the defect’s requirements. The
muscle conforms to the complex geometry of the defect, sealing exposed dura and/or sinonasal cavities.
This feature helps to minimize the occurrence of a sinocutaneous fistula; such fistulae are exceedingly
difficult to heal owing to persistent pressure from nasal airway.
mebooksfree.net

Region II
Resection of region II tumors, frequently, is performed through an anterior transmaxillary approach.
After resection of the middle cranial fossa, the dura will be in direct communication with the
nasopharynx; if the resection also necessitates a maxillectomy, then the oral cavity and oropharynx will
be in direct communication with the intracranial space as well (Figure 38.8). The temporalis muscle may
reach this area but often does not provide adequate bulk, especially after radiation-
 related atrophy
occurs. In such cases, a bulky myocutaneous flap, such as the ALT or RAM free flaps, has great utility.
When there is no oral mucosal, palatal, or external cheek defect, the skin paddle of the free flap can be de-
epithelialized and the entire flap buried. The adipodermal component of the flap provides bulk, which is
less prone to radiation atrophy than muscle; the muscle component serves as an adequate seal against
exposed dura mater. Persistent bulk and volume maintenance is important in these reconstructions to not
only maintain facial contour but also to adequately support the skull base so as to prevent herniation of
the intracranial contents into the pharynx or oral cavity.
mebooksfree.net

FIGURE 38.8 A. Zone II skull base defect combined with orbito- and hemipalatomaxillectomy with resection of the middle
cranial fossa skull base. B. Multi-paddle free anterolateral thigh myocutaneous free flap with vastus lateralis to resurface the
resected skull base. Anastomosed to facial artery, common facial vein, and external jugular vein via vein grafts. C,D.
Postoperative result.
As in reconstruction of the maxillectomy defect, if the orbital floor is resected and the globe is spared,
then skeletal reconstruction of the orbital floor is mandatory. Failing to reconstruct the orbital floor or
performing an inaccurate reconstruction can result in enophthalmos, vertical dystopia, or diplopia.
Various alloplastic materials are commercially available; alternatively, an autologous calvarial or iliac
crest bone graft can be used. Although autologous grafts can be revascularized, our own experience does
mebooksfree.net