Focal acral hyperpigmentation in a patient undergoing chemotherapy with capecitabine.

Capecitabine is a prodrug of fluorouracil. Systemic immunosuppression has been reported as a cause of eruptive pigmented lesions, although the mechanisms causing this eruption are not known. A 58-year-old woman undergoing chemotherapy with capecitabine presented with multiple pigmented macules on the skin and tongue, and generalized hyperpigmentation, which finally faded after the drug was discontinued. Capecitabine may induce the growth of normal and dysplastic melanocytic nevi, and lentiginous melanocytic hyperplasia. Careful follow-up is mandatory, since the risk of developing melanoma in these cases remains uncertain.