Histologic response of in-transit melanoma to topical DPCP: A case report

Diphenylcyclopropenone (DPCP) is a modulator of CD8+ T-cell response, as well as Th17 response, that has shown positive treatment responses when applied topically to in-transit melanoma.1 We report a 48-year-old female who presented with a 10 week history of a multifocal non-pigmented lesion of the posterior lower leg. Multiple punch biopsies of the lesions showed melanoma (T2N2cM0, stage IIIb) primarily in the dermis, Breslow depth 1.0 mm, with some junctional involvement and focal pagetoid spread.