Malignant melanoma and extramammary Paget's disease in the same patient

Axillary Paget's disease was found in a 34-year-old man who died of metastatic malignant melanoma. The primary cutaneous malignant melanoma was diagnosed 6 years before the patient's demise and was confirmed by the presence of melanin, a positive dopa reaction, and immunohistochemical demonstration of S-100 protein in neoplastic cells. Postmortem examination revealed Paget's disease of the axillary skin in addition to widespread metastases of malignant melanoma. Paget cells were positive for periodic acid-Schiff reaction and alcian blue. They were also immunohistochemically positive for carcinoembryonic antigen, but were negative for S-100 protein. This association of malignant melanoma and Paget's disease in the same person has not, to the best of our knowledge, been described before.