Desmoplastic malignant melanoma of the lip: a report of 6 cases and review of the literature.

Desmoplastic malignant melanoma is a rare neoplasm consisting primarily of spindle-shaped melanoma cells embedded in a fibrous stroma, with approximately 6% of cases occurring in the lip. A literature search revealed that most reported cases occur in sun-exposed areas in older men. Few cases of desmoplastic malignant melanoma of the lip in young people (in their mid-twenties) have been described. We report 6 previously undocumented cases of labial desmoplastic malignant melanoma occurring in young individuals and review 20 cases from the literature. Physicians should consider the possibility of desmoplastic malignant melanoma in young people who present with atypical lip lesions, which on histopathologic analysis demonstrate spindle-cell hyperplasia. Although this diagnosis is rare and there have not been reports of such patients in the literature thus far, our findings should alert clinicians to the possibility of desmoplastic malignant melanoma as a diagnosis for lip lesions in young people.