SAN FRANCISCO — Pigmented lesions revealed few clues as to their true histologic identities in a 5-year retrospective study, Dr. Roland M. Strauss said in a poster presentation at the annual meeting of the American Academy of Dermatology.
Of 434 excised lesions, nearly half proved to be benign melanocytic nevi, but more than 100 were invasive melanomas or displayed severely dysplastic features or in situ melanoma.
Telling the difference proved difficult, even for specialists at a pigmented lesion clinic at Leeds (England) General Infirmary. The best predictors of melanoma in the study were older patient age, larger lesion diameter, blue or blue-gray lesion hue, and male sex, said Dr. Strauss of the infirmary.
Only advanced age was predictive of severe histologic dysplasia or in situ melanoma vs. nevi with mild to moderate atypia, he said in his poster presentation.
“Our results confirm the difficulty experienced by dermatologists in distinguishing atypical nevi with mild to moderate histologic atypia from those with severe histologic dysplasia or melanoma in situ,” Dr. Strauss wrote. “In order not to miss any lesions with severe dysplasia/melanoma in situ, the excision of a number of benign lesions with only mild to moderate dysplastic features will therefore have to be accepted,” he suggested.