Atlas of General Surgical Techniques (Courtney M. Townsend Jr., B. Mark Evers)

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After removal of blue and/or hot nodes, palpation of the surgical bed for enlarged, firm, or otherwise suspicious lymph nodes should be performed. A pathologic lymph node may not be hot or blue for two reasons: (1) the lymph node is completely replaced with tumor and the lymphatics are “blocked” from uptake of any tracer, and (2) unexplainable falsenegative results do occur. A tumor-positive, nonradioactive or nonblue node should still be considered a “sentinel” node when removed because it accurately staged the axilla of that patient. If no SLN can be identified, then a default level I/II axillary dissection must be performed. On average, two to three SLNs are removed per case for breast cancer, and one to two for melanoma.

SLN biopsy is followed by either breast-conserving therapy or mastectomy. If mastectomy is planned, it is helpful to perform the SLN biopsy first by opening a small portion of the axillary portion of the mastectomy incision before raising the flaps. Depending on the tumor location, raising the entire superior flap may result in blue dye spillage into the axilla, which can make identification of the SLN difficult.

3. CLOSING

The axilla is irrigated and hemostasis is achieved. The wound is closed in two layers: an interrupted watertight layer with absorbable sutures that reapproximates the clavipectoral fascial layer and a subcuticular layer to close the skin edges.

STEP 4: POSTOPERATIVE CARE

Should the patient require a completion axillary lymph node dissection, the previous SLN biopsy scar should be removed en bloc with the specimen.

STEP 5: PEARLS AND PITFALLS

Unless formally trained during residency or fellowship, all surgeons must climb the learning curve and begin to learn this procedure by offering SLN biopsy with planned backup axillary dissection. This will allow the individual surgeon to calculate his or her own identification and false-negative rates. Surgeons who wish to adopt this technology must ensure that in their own hands, a false-negative rate of 5% or lower and an identification rate of 95% or higher are achieved. The false-negative rate significantly decreased from 9% for surgeons who performed 20 or fewer procedures to a rate of 1.9% for those who performed more than 20 procedures. It must be emphasized, however, that false-negative results and nonidentification of the SLN can occur even after appropriate surgical training. Patients must be told of the small risk of a false-negative result and balance this against the benefits of a less invasive procedure. If staged to be SLN negative, the patient may have a small lifetime risk of axillary recurrence due to the potential of a false-negative result.

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Although limited data suggest that SLN biopsy may be feasible following previous SLN biopsy, previous neoadjuvant chemotherapy, or radiotherapy, if successful mapping is not achieved by the technical criteria defined previously, the standard levels I and II axillary dissection should be performed. Many studies demonstrate adequate identification rates, but few report false-negative rates in these clinical circumstances.

The role for SLN biopsy in inflammatory breast cancer has not been defined.

Some surgeons advocate frozen section analysis of the SLN, whereas others never use frozen section analysis because of the issue of sampling error in this setting. The decision to incorporate frozen section evaluation into one’s program depends on the comfort level of the pathologist and surgeon. Patients are informed preoperatively that frozen section analysis may miss some positive SLNs, which subsequently will be found on final pathologic sections. The sensitivity of frozen section analysis decreases with micrometastatic deposits, defined as tumor 2 mm or smaller in the SLN. If there is a positive SLN found on frozen section examination, this is an indication for completion axillary dissection under the same anesthetic setting. If frozen section evaluation is not used, the patient can return to the operating room (1 or 2 weeks later) for completion level I/II node dissection after final sections have been confirmed to be tumor-positive.

For melanoma, frozen section analysis is never recommended. Because both serial sectioning and immunohistochemistry for tumor markers (e.g., S-100, MART-1) are required, permanent sections are necessary for accurate histopathologic diagnosis.

Injection technique: Many centers perform peritumoral injection of both blue dye and radioactive colloid. However, peritumoral injection of radioactive colloid results in a large zone of diffusion that can obscure the objective of locating the axillary SLN, especially for upper outer quadrant tumors. To minimize this “shine-through” effect, some centers use a sterile lead shield to block the radioactive interference from the upper outer quadrant of the breast. Furthermore, peritumoral injection results in relatively little uptake of the tracer from the breast tissue compared with dermal injection. Studies have shown that dermal injection of radioactive colloid significantly improves SLN identification rate and minimizes the false-negative rate. For instance, dermal injection of radioactive colloid is associated with SLNs that are fivefold to sevenfold more radioactive, or hot, than with the peritumoral injection method. When the dermal injection is used, the skin overlying the tumor can be retracted medially, away from the axilla, to facilitate accurate gamma probe localization.

STEP 6. CONCLUSION

Implementation of SLN biopsy requires multidisciplinary cooperation and high standards of quality control. Ongoing studies, such as the American College of Surgeons Oncology Group Trials Z0010 and Z0011 and the NSABP trial B-32, should provide answers to many of the remaining clinically relevant questions.

SELECTED REFERENCES

1. Morton DL, Wen DR, Wong JH, et al: Technical details of intraoperative lymphatic mapping for early stage melanoma. Arch Surg 1992;127:392-399.

2. Giuliano AE, Kirgan DM, Guenther JM, Morton DL: Lymphatic mapping and sentinel lymphadenectomy for breast cancer. Ann Surg 1994;220:391-401.

3. McMasters KM, Giuliano AE, Ross MI, et al: Sentinel lymph node biopsy for breast cancer: Not yet the standard of care. N Engl J Med 1998;339:990-995.

4. McMasters KM, Chao C, Wong SL, et al: Sentinel lymph node biopsy in patients with ductal carcinoma- in-situ: A proposal. Cancer 2002;95:15-50.

5. McMasters KM, Wong SL, Chao C, et al: Defining the optimal surgeon experience for breast cancer sentinel lymph node biopsy: A model for implementation of new surgical techniques. Ann Surg 2001;234:292-300.

C H A P T E R 12

EXCISION OF BENIGN

BREAST LESION

Courtney M. Townsend, Jr.

STEP 1: SURGICAL ANATOMY

Knowledge of breast anatomy is important. Benign lesions are usually fibroadenomas, papillomas, or fibrocystic condition.

Fibroadenomas usually occur in younger women, often in their 20s, and often are characterized by a round, smooth, “slippable” mass. Indication for operation is patient concern, because fibroadenoma is not a premalignant lesion.

STEP 2: PREOPERATIVE CONSIDERATIONS

I favor the patient having general anesthesia for all of these resections for the following reasons:

In young women with dense breast tissue, local anesthetic diffuses poorly. Resecting a lesion at any depth or size often is much more uncomfortable than one would think.

With fibrocystic condition in premenopausal or postmenopausal women, the fibrous nature of the reaction sometimes is such that local anesthetic does not diffuse well throughout the breast. If local anesthetic is chosen, however, I always avoid the use of epinephrine because bleeding, which occurs some time later, may not be detected at the time of operation.

Many lesions can be reached through an areolar margin incision, even though they appear initially to be some distance from the areolar margin. However, if a lesion is too far from the areolar margin, then an incision directly over the lesion in Langer’s lines paralleling the areolar margin should be used. Radial incisions are to be avoided

(Figures 12-1 and 12-2).

A preoperative mammogram is required for all patients who are to have a breast operation.

Prophylactic antibiotics are given.

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Incision lines

Tumor

FIGURE 12–1

Incision near areolar edge

FIGURE 12–2

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STEP 3: OPERATIVE STEPS

1.INCISION

Regardless of the size of the incision, flaps are raised after the skin incision has been carried down through the intramammary fat.

2.DISSECTION

The lesion is then approached directly or, if it is not a palpable lesion, the area of breast tissue into which the localizing wire disappears is resected (Figures 12-3 and 12-4).

The portion of tissue into which the wire disappears is excised blindly and the specimen mammography is required to determine that the lesion has been removed.

For a solid lesion, the margin is easily determined. I use a traction suture placed in a figure- of-eight fashion rather than clamps.

Before final removal of the lesion, the borders are marked. I use a short suture on the superior margin, a long suture for the lateral margin, and a traction suture of intermediate length marks the superficial margin.

Hemostasis is achieved with coagulating cautery, and the wound is irrigated with hydrogen peroxide to aid in detection of bleeders.

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3. CLOSURE

The breast tissue is not closed and the wound is closed with subcuticular absorbable sutures (Figures 12-5 and 12-6).

The wound is covered with a plastic dressing.

STEP 4: POSTOPERATIVE CARE

I prefer nonopioid analgesics.

An ice pack is used for the first 12 to 24 hours.

I recommend that the patient wear a new sports bra for support and wear it until the discomfort has disappeared.

STEP 5: PEARLS AND PITFALLS

Avoid local anesthetic in dense breasts.

Avoid epinephrine if local anesthetic is to be used.

Traction sutures prevent destruction of the specimen to be excised by multiple applications of forceps or clamps. I use coagulating cautery for dissection and therefore take a more generous margin because there may be coagulation artifact produced in the specimen.