A 68-yrs-old woman is to have a suspected melanoma excised from her trunk. It appears to be a thin melanoma, less than 1 mm deep. The smallest margin to plan for the excision is:
a. All suspicious lesions should undergo excisional biopsy. A 1-mm margin of normal skin is taken if the wound can be closed primarily.
b. Lesions 1 mm or less in thickness can be treated with a 1-cm margin. For lesions 1 mm to 4 mm thick, a 2-cm margin is recommended. The surrounding tissue should be removed down to the fascia to remove all lymphatic channels. If the deep fascia is not involved by the tumor, removing it does not affect recurrence or survival rates, so the fascia is left intact. If the defect cannot be closed primarily, a skin graft or local flap is used.
d. With very thick lesions (more than 4 mm), it is highly likely that the tumor cells have already spread to the regional lymph nodes and distant sites. Removal of the lymph nodes has no effect on survival