Abstract

A 86-year-old Japanese man had a Merkelcell carcinoma on his left instep. The lesion was a nodule, 28×25×10mm in size, surrounded by a reddish plaque measuring 52×35mm. Histologicalexamination of the nodule revealed proliteration of small basophilic neoplastic cells in the dermis.
The cells were immunohistochemically positive for NSE and electoron microscopic study detected dense core granules in their cytoplasm.
The epidermis of the plaque lesion histologically showed features of Bowenoid changes. In addition, eccrine fibroadenomatous changes of the epidermis were found in the epidermis neighboring the nodular lesion. Association of Merkel cell carcinoma and Bowen's disease has been well documented in the literature. However, the present case was unique because three components of Merkel cell carcinoma, Bowen's disease and eccrine fibroadenomatous lesion coexisted within a single lesion.