Abstract

We reported a case of merkel cell carcinoma (MCC) admixed with squamous cell carcinoma (SCC). The patient was a 82-year-old women who developed a red, domeshaped tumor, 18mm in diameter, on her left cheek. Histologically the tumor showed undifferentiated small cell malignant neoplasm that coexisted with SCC. Sweat gland differenciation was shown in a part of SCC. An immunohistochemical study showed that MCC was positive for neuron specific enolase and synaptophysin, SCC was positive for carcinoembryonic antigen and cytokeratin 20. An ultra-structual study showed dense core granules within the cytoplasm of MCC.