Abstract

We report a case of Merkel cell carcinoma associated with Bowen's disease that developed in a 95-year-old female. The patient had an ulcerated nodule in the erythematous plaque of her left shoulder. Histological examination revealed Bowen's disease with a deep infiltrating small cell tumor. Ultra-structural studies demonstrated dense core granules within those small cells. The transition between the two tumors was not identified. It has been reported that in certain organs (skin, stomach, intestine, uterus), neuroendocrine tumors (Merkel cell carcinoma, carcinoid, small cell carcinoma of the lung) are often co-existence with other epithelial malignancies such as squamous cell carcinoma or adenocarcinoma.