Chapter 32: Soft Tissue Sarcoma and Skin
Which of the following is the appropriate surgical management of a 1.5-mm melanoma?
(A) Excision with 1.0-cm margins
(B) Excision with 2.0-cm margins
(C) Excision with 2.0-cm margins and sentinel lymph node (SLN) biopsy
(D) Excision with 2.0-cm margins and lymph node dissection
(E) Excision with 3.0-cm margins
(C) The National Comprehensive Cancer Network (NCCN) Guidelines in Oncology has a set of recommended guidelines for treating malignant melanoma based on depth of the lesion. The current standard is a 1-cm margin for lesions 1 mm or less in depth. For lesions 1–2 mm in depth, a 2-cm margin is appropriate, but a smaller margin is accepted in a cosmetically sensitive area. A smaller margin is also appropriate when a limited resection can help preserve function, such as when crossing a joint. A depth of 2 mm or greater requires a 2-cm margin, and some advocate for a 3-cm margin for lesions greater than 4 mm deep. The tissue should be excised down to the level of the fascia to include all subcutaneous lymphatic channels.
To provide adequate staging and treatment, lymph node assessment is necessary. The SLN biopsy has become the standard of care and should be performed routinely for melanomas with a depth of 1 mm or greater. It should also be considered for lesions between 0.75 and 1 mm with high-grade features (ulceration, lymphovascular invasion, and high mitotic rate). Lesions less than 0.75 mm are unlikely to have regional lymphadenopathy and do not require biopsy.
Sentinel lymph node biopsy is a sampling of the first draining lymph node(s) from the lesion and the most likely to have metastasis if any is present. For melanoma, lymphatic mapping (Fig. 32-5) is performed to identify the draining nodal basin. Lymphatic mapping is performed by injecting either isosulfan blue dye (Fig. 32-6) or technetium-labeled sulfur colloid at the site of the lesion and then identifying the “hot” or blue nodes. The hot or blue nodes are the sentinel nodes. They are identified with a gamma probe and exploration of the lymph node basin.
FIGURE 32-5. Lymphoscintigraphy using sulfur colloid labeled with technetium-99.
FIGURE 32-6A. Blue dye injected intradermally around the tumor.
FIGURE 32-6B. Chart of options for melanoma treatment (from Brunicardi F, Andersen DK, Billiar TR, et al., (eds.), Schwartz’s Principles of Surgery. 9th ed. New York, NY: McGraw-Hill; 2010: Chapter 16: Image 16-13).
FIGURE 32-6C. Flow chart ...