Surgery for Melanomas

Nevi are so common that they have a wide range of classifications. Blue nevi occur very deep in the dermis. Compound nevi are very dark in color and are slightly raised. Intradermal nevi are usually flesh-colored and raised. Intramucosal nevi occur in the mouth or genital area. Nevi of ito and nevi of ota are found on the shoulder or face, which are flat and brownish in appearance.

Clark’s nevi are also called dysplastic nevi. They tend to stem from abnormal cell growth and can be pre-cancerous. These moles tend to be larger with irregular borders and coloration. As a result, they look like melanomas, and are often removed to confirm the diagnosis. Dysplastic nevi do not morph into melanomas, but are markers of risk when there are many of them.

Epidermal nevi usually appear on the upper half of the body. The recognized cause of these nevi is genetics. Giant hairy nevi are often very large and hairy and are unsightly. In terms of health, they can pose a risk as melanoma may be present in approximately 10-15% of the cases. Spitz nevi usually occur on children. They are often reddish in color and are raised.

Diagnostic punch or excisional biopsies may appear to excise the tumor, but further surgery is often necessary to reduce the risk of recurrence. Complete surgical excision with adequate margins and assessment for the presence of detectable metastatic disease along with short- and long-term followup is standard.

Often this is done by a wide local excision with 1 to 2 cm margins. Melanoma-in-situ and lentigo malignas are treated with narrower surgical margins, usually 0.2 to 0.5 cm. Many surgeons consider 0.5 cm the standard of care for standard excision of melanoma-in-situ, but 0.2 cm margin might be acceptable for margin controlled surgery (Mohs surgery).

The wide excision aims to reduce the rate of tumour recurrence at the site of the original lesion. This is a common pattern of treatment failure in melanoma. Considerable research has aimed to elucidate appropriate margins for excision with a general trend toward less aggressive treatment during the last decades.

Mohs surgery has been reported with cure rate as low as 77% and as high as 98% for melanoma-in-situ. Melanomas which spread usually do so to the lymph nodes in the region of the tumor before spreading elsewhere. Attempts to improve survival by removing lymph nodes surgically were associated with many complications but unfortunately no overall survival benefit.

Although controversial and without prolonging survival, sentinel lymph node biopsy is often performed, especially for T1b/T2+ tumors, mucosal tumors, ocular melanoma and tumors of the limbs. A process called lymphoscintigraphy is performed in which a radioactive tracer is injected at the tumor site in order to localize the sentinel nodes.

Further precision is provided using a blue tracer dye and surgery is performed to biopsy the nodes. Recently the technique of sentinel lymph node biopsy has been developed to reduce the complications of lymph node surgery while allowing assessment of the involvement of nodes with tumor.

As with other skin abnormalities, moles are classically removed by laser, surgery, or electrocautery. Most of these treatments require multiple visits to the doctor. Surgery, the option doctors commonly offer, involves cutting out the mole. The resulting wound requires stitches, which will in turn leave a scar.