Table 3.

Clinical considerations in margin selection for melanoma in situ

5 mm clinical margins may be sufficient if all of the following criteria are met

Well-circumscribed lesions

Small lesions, < 1 cm in diameter

Non-chronically sun-exposed skin (trunk, proximal extremities)

Absence of histological evidence of chronic sun damage/solar elastosis on biopsy (i.e., not LM)

10 mm clinical margins should be considered for

Areas if sufficient skin laxity where larger margins can be achieved without untoward consequence

Ill-defined lesions

Lesions > 1 cm in diameter

Chronically sun-exposed skin, such as the head and neck and distal extremities

Diagnosis of LM on dermatopathology review of biopsy

Acral lesions

> 10 mm clinical margins should be considered in

Very large lesions > 3 cm in diameter, especially those on chronically sun-exposed skin

Head and neck location

MIS melanoma in situ, LM lentigo maligna