Skin Disorders Guide

All pigmented lesions (a type of skin disorder) should be periodically and systematically examined with the forgoing criteria in mind. Biopsy can be justified when even only one of these criteria is met, even though melanoma is not particularly likely to be present unless two or more of the criteria are present. When two criteria are present, biopsy is probably mandatory. Many physicians cover their uncertainty regarding recognition of possible malignant features in a pigmented lesion by suggesting that the patient watch it and return for repeat examination if any evidence of change develops. Unfortunately, patients are neither emotionally nor medically prepared to carry out this advice. Thus, while it appears to relieve the physician of responsibility, it transfers an undue burden onto the patient. In almost all instances, when a question arises, it is better to make a commitment one way or the other. Thus, if after examination a question remains about a pigmented lesion, biopsy is warranted. If, on the other hand, you are satisfied that no Criteria for suspicion are present, the patient should be so notified. When multiple suspicious lesions (dysplastic nevi) are present, a referral for examination (and possible follow-up) by a dermatologist is probably warranted.

Biopsy of any suspicious pigmented lesion should usually be carried out by elliptical rather than shave excision. Margins of 1 to 2 mm are all that is needed. With this technique the entire specimen is available for stepped histologic examination. Moreover, the possibility of repigmentation (which often causes alarm both in the patient and in a subsequent examiner) is eliminated.

Lesions too large to be removed by simple excision should have one or more punch biopsies taken from the most suspicious areas. Reexcision with grafting can be canied out a week or so later if necessary. It is not completely clear whether such incisional biopsies influence the ultimate prognosis, but when confronted with a large lesion, this represents the only practical approach.