Relationship between cause of referral and diagnostic outcome in pigmented lesion clinics

Pigmented lesion clinics (PLCs) are permanent units to which subjects presenting with suspicious pigmented skin lesions can be rapidly referred and which can provide a prompt response to an individual's concern about melanoma. However, little is known about the melanoma detection rate in these clinics, in particular with regard to intermediate risk populations. We report a survey involving more than 1000 subjects consecutively referred by family doctors to six Italian PLCs. Using a histological diagnosis of melanoma as the endpoint, the pooled melanoma detection rate at these PLCs was 1.5% (one melanoma for diagnosed every 64 subjects examined), and the ratio between the number of melanomas and benign lesions excised for diagnostic verification was 1: 5.8 (16 melanomas and 93 benign lesions). Almost all the melanomas (15 out of 16) were detected in subjects who had requested referral for a specific doubtful lesion (group A) or for the presence of melanoma risk factors (previous melanoma, large number of common and atypical naevi, family history of melanoma) (group B). Only one melanoma was detected amongst the 418 subjects seeking consultation for concern about their moles (group C) (P = 0.004). The positive and negative predictive values of the referral groups A and B combined were 2.5% and 99.7%, respectively. Since the probability of detecting a melanoma in subjects referred only for reassurance about their moles, which nevertheless represented 43% of the subjects examined, is very low, an optimized role for PLCs in melanoma prevention would be to limit consultation to subjects who present for examination of a specific lesion or who have one or more risk factors for melanoma.