Atlas Các Kỹ Thuật Phẫu Thuật Tuyến Vú (Atlas of Breast Surgical Techniques)

Chapter 24 • In Vivo Intraoperative Radiation Therapy for Breast Cancer 409
Figure 24-8
Figure 24-9
Figure 24-10

410 Section VI • Surgical Techniques to Assist Irradiation
◆ Once the patient and the applicator have been placed under the Mobetron (Fig. 24-11), a geo-
metric alignment of the treatment applicator with the gantry head of the Mobetron is achieved
using a laser alignment system (Fig. 24-12).
◆ The operating room team moves to a substerile location outside of the operating room, and the
anesthesiologist monitors the patient through a window in the substerile location while the
radiation is delivered (Fig. 24-13).
◆ The patient is returned to her previous position and the Bookwalter retraction system is
removed.

Chapter 24 • In Vivo Intraoperative Radiation Therapy for Breast Cancer 411
A
Figure 24-11
B
Figure 24-12
Figure 24-13

412 Section VI • Surgical Techniques to Assist Irradiation
4. Segmental Mastectomy and Wound Closure
◆ The tumor is excised (see Chapter 15), appropriately marked for pathology (Fig. 24-14), and
sent for specimen mammography.
◆ The incision is closed in standard fashion, such as with a simple interrupted 3-0 Vicryl suture
and a running 4-0 Monocryl suture (Fig. 24-15).
◆ Sterile dressings and a surgical bra are applied.
Step 4. Postoperative Care
◆ Routine postoperative care is similar to care for a segmental mastectomy and a sentinel lymph
node biopsy (see Chapters 11 and 15).

Chapter 24 • In Vivo Intraoperative Radiation Therapy for Breast Cancer 413
A
B
Figure 24-14
A
B
Figure 24-15

414 Section VI • Surgical Techniques to Assist Irradiation
1. Treatment of Patients Who Are Ineligible Based on Final Pathologic Evaluation
◆ Because the resection is performed after irradiation, fi nal pathologic characteristics will not be
available at the time of treatment. If tumors are ultimately found to be larger than 3 cm, to have
an extensive intraductal component, or to be node positive, then external-beam radiation
therapy will follow, which is standard therapy. The IORT treatment serves as the boost.
◆ Patients who do not have tumor-free surgical margins (>1 mm) require a reoperative segmental
mastectomy. If the patient has one or two tumor-involved surgical margins, she will be consid-
ered a candidate for a reoperative segmental mastectomy. The reoperative segmental mastec-
tomy is performed in a standard fashion. If there is residual tumor with negative margins on
reexcision, then whole-breast external-beam radiation is given for 5 weeks (the IORT that was
previously given essentially serves as the radiation boost). If the reoperative segmental mastec-
tomy fails to achieve complete tumor-free surgical margins, the patient is deemed a failure at
breast preservation and proceeds to mastectomy.

Chapter 24 • In Vivo Intraoperative Radiation Therapy for Breast Cancer 415
Step 5. Pearls and Pitfalls
◆ General anesthesia must be administered for this procedure.
◆ Even if the tumor is palpable it should be wire localized, because this helps to ensure that the
IORT is delivered directly over the tumor.
◆ Ensure that the operating table is rotated 180 degrees before administering general anesthesia.
The table cannot fi t under the Mobetron machine if it is not rotated.
◆ Ensure that the patient is securely fastened to the operating table with a seatbelt because the
whole table may need to be tilted to achieve the correct positioning for delivery of the
radiation.
Bibliography
Ollila DW, Klauber-DeMore N, Tesche LJ, et al: Feasibility of breast preserving therapy with single fraction in situ radiotherapy delivered
intraoperatively. Ann Surg Oncol 2007;14:660-669.
Stitzenberg KB, Klauber-DeMore N, Chang XS, et al: In vivo intraoperative radiotherapy: A novel approach to radiotherapy for early stage
breast cancer. Ann Surg Oncol 2007;14:1515-1516.

Step 1. Surgical Anatomy
◆ Figure 25-1 demonstrates the relevant anatomy for intraoperative radiation therapy (IORT)
treatment.
Step 2. Preoperative Considerations
◆ Small, screen-detected breast cancers in older women are ideal for IORT treatment.
◆ Mammography (Fig. 25-2, A) and ultrasonography (Fig. 25-2, B) show a lesion that is isolated
and without extensive calcifi cations.
◆ Currently, patients are treated with orthovoltage (50-KeV) IORT only in the context of the
TARGIT (targeted intraoperative radiation therapy) trial.
◆ Eligible patients who have a relatively low risk of local and distant relapse are selected for this
randomized, controlled trial (Fig. 25-3). It is also important to obtain negative pathologic
margins at the time of initial lumpectomy/partial mastectomy.
◆ Patients with the following characteristics appear to be ideal for IORT:
▲ Biopsy-proven invasive ductal carcinoma
▲ Age greater than 50 years
▲ Tumor size less than 2 cm
▲ Clinically negative nodes
▲ Screen-detected disease
▲ No malignant calcifi cations beyond tumor mass
◆ Patients with invasive lobular cancers are excluded from the study, as are those with an extensive
intraductal component.
◆ Breast-specifi c preoperative work-up generally consists of the following:
▲ History (usually asymptomatic; exclude those with concerning nipple discharge)
▲ Physical examination (no signs of nodal disease, locally advanced cancer, or fi xation to
pectoralis major)
▲ Mammography
▲ Ultrasonography
▲ Core biopsy
▲ Axillary ultrasonography
▲ Magnetic resonance imaging (selected patients)
Targeted Intraoperative
Radiation Therapy (TARGIT)
David R. McCready and Michael Andrew Henderson
CHAPTER 25
416

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 417
Lymph nodes
Sternum
Pectoralis minor
Figure 25-1

418 Section VI • Surgical Techniques to Assist Irradiation
A
B
Lesion
Lesion
Lesion
Figure 25-2

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 419
Breast cancer patient suitable for breast-
conserving therapy
Randomization
Study Arm
Conventional Arm
Wide local excision of primary tumor with
definitive sentinel node biopsy and/or
axillary dissection

Intraoperative radiation therapy
Wide local excision of primary
tumor with definitive sentinel node
biopsy and/or axillary dissection
Histopathology shows
a) Invasive lobular carcinoma, or
b) Extensive intraductal component, or
c) An adverse criterion*
Yes
No
Whole-breast
radiation therapy
omitting the
tumor bed
boost
No further local
treatment
Conventional course of
postoperative external-beam
radiation therapy to the
whole-breast with
tumor bed boost
Adjuvant systemic treatment as appropriate
Regular follow-up
*Decided by each center at the outset - such as grade III, node involvement, margin
involvement, etc.
Figure 25-3

420 Section VI • Surgical Techniques to Assist Irradiation
Step 3. Operative Steps
◆ IORT is ideally given at time of defi nitive breast surgery, but some centers deliver IORT to the
lumpectomy cavity 1 to 3 days postsurgery when fi nal pathology confi rms negative margins
and nonlobular histology.
◆ Before surgery, the breast has been injected with technetium-sulfur colloid for sentinel node
mapping and a wire localization procedure has been performed to guide excision of nonpalpable
tumors (Fig. 25-4).
◆ Preoperative antibiotics are given before incision.
◆ The procedure is performed under general anesthesia. Blue dye is injected around the tumor
site. The sentinel node biopsy is performed fi rst.
◆ Incisions are kept relatively small and placed directly over the tumor (Fig. 25-5). Drawing the
incision before surgery with the patient upright can aid in cosmesis because different areas of
the breast pull downward in different amounts depending on skin laxity and breast ptosis.
◆ Intraoperative ultrasonography can aid in locating small tumors. Skin is usually not excised
unless the tumor is very superfi cial. The surgeon should attempt to leave 1 cm of subcutaneous
tissue on the undersurface of the skin; thin fl aps are discouraged (Fig. 25-6).

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 421
Technetium-
sulfur colloid
Hook wire
Figure 25-4
A
Incision
Incision made
directly over tumor
B
Proposed line of excision
Figure 25-5
Figure 25-6

422 Section VI • Surgical Techniques to Assist Irradiation
◆ Lumpectomies are best performed in a systematic fashion, starting with the superior portion
followed by both medial and lateral sides, then the posterior margin down to pectoralis fascia,
and fi nally the inferior margin. Meticulous hemostasis is important.
◆ Specimen radiography with mammography (or ultrasonography) is performed and close margins
can be reexcised (Fig. 25-7). Margin assessment can be performed as needed by frozen-section
analysis or touch imprint cytology as clinically or radiologically directed.
◆ The size of the cavity is estimated and the Intrabeam applicator (Carl Zeiss Meditec, Jena,
Germany) is placed into the cavity. An appropriate size is selected to achieve a snug fi t with a
pursestring suture (Fig. 25-8). The purse string is best placed in breast tissue so it can ensure
there are no gaps between applicator and tissue. Intraoperative ultrasonography can be used to
ensure there are no gaps between applicator surface and cavity margin.
◆ Dosimetry is calculated so that 20 Gy is delivered at the surface of the applicator. The dose
to breast tissue at a 1-cm depth from the cavity is about 5 Gy. Skin edges are everted if subcu-
taneous tissue is less than 1 cm thick.

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 423
A
B
C
Figure 25-8
Wire
Wire
Specimen
A
B
Figure 25-7

424 Section VI • Surgical Techniques to Assist Irradiation
◆ The radiation delivery device is attached to the movable boom (Fig. 25-9), and the apparatus
is sterilely draped with the applicator (Fig. 25-10).

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 425
A
B
Figure 25-9
B
A
Figure 25-10

426 Section VI • Surgical Techniques to Assist Irradiation
◆ The applicator is inserted into the cavity and the pursestring suture tied (Figs. 25-11 and
25-12). A posterior blocking shield can be used on the pectoralis fascia if the beam is directly
aimed at the heart (Fig. 25-13).
◆ Duration of IORT is calculated based on applicator diameter (Table 25-1). Shielding is placed
over the skin surface to reduce radiation scatter (Fig. 25-14), and the IORT is delivered
(Fig. 25-15).
TABLE 25-1 Treatment Time for 20 Gy at the Applicator Surface
APPLICATOR (MM)
TREATMENT TIME (MIN)
15
7.07
20
11.53
25
17.43
30
24.98
35
18.57
40
26.8
45
36.58
50
48.82

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 427
Shield to
protect heart
Figure 25-11
Figure 25-12
Figure 25-13
Figure 25-14

428 Section VI • Surgical Techniques to Assist Irradiation
◆ During IORT, everyone leaves the room except the radiation therapist and anesthesiologist, who
are behind a transparent lead glass shield and wearing appropriate shielding. The patient is
ventilated and kept paralyzed during the IORT to minimize movement.
◆ On completion, the pursestring suture is cut, the applicator removed, and a visual inspection
for bleeding performed. Subcuticular sutures are used to close the wound and Steri-Strips are
applied (Fig. 25-16).
Step 4. Postoperative Care
◆ Postoperative care is the same as that given for lumpectomy (see Chapter 6).
◆ No special precautions are necessary.
Step 5. Pearls and Pitfalls
◆ Careful patient selection is crucial.
◆ The tumor should be centered within the specimen and a 1-cm margin of normal tissue obtained
around the tumor. Larger excision cavities require larger applicators and correspondingly longer
treatment times.
◆ The anterior margin is often the most diffi cult to control because a 1-cm buffer between the
tumor and the specimen edge is the goal, but 1 cm of subcutaneous fat also should be left with
the skin. The tumor margin is the fi rst priority, and remaining skin can be managed by purse-
string suture and skin eversion, or skin excision if necessary.
◆ The cavity must be in contact with applicator. Drape tape or OpSite (Smith & Nephew, London)
can be used to hold the breast in an appropriate position (see Fig. 25-12).
Bibliography
Holmes DR, Baum M, Joseph D: The TARGIT trial: Targeted intraoperative radiation therapy versus conventional postoperative whole-
breast radiotherapy after breast-conserving surgery for the management of early-stage invasive breast cancer (a trial update). Am J Surg
2007;194:207-210.
Schiller DE, Le LW, Cho, BCK, et al: Factors associated with negative margins of lumpectomy specimen: Potential use in selecting patients
for intraoperative radiotherapy. Ann Surg Oncol 2007;15:833-842.
Vaidya JS, Baum M, Tobias JS, et al: Targeted intra-operative radiotherapy (TARGIT): An innovative method of treatment for early breast
cancer. Ann Oncol 2001;12:1075-1180.
Vaidya JS, Baum M, Tobias JS, et al: Targeted intraoperative radiotherapy (TARGIT) yields very low recurrence rates when given as a boost.
Int J Radiat Oncol Biol Phys 2006;66:1335-1338.

Chapter 25 • Targeted Intraoperative Radiation Therapy (TARGIT) 429
A
B
Figure 25-15
Figure 25-16