A Case of Intraepidermal Merkel Cell Carcinoma within Squamous Cell Carcinoma In-Situ: Merkel Cell Carcinoma In-Situ?Al-Ahmadie, Hikmat A. MD*; Mutasim, Diya F. MD†; Mutema, George K. MD, PhD*The American Journal of Dermatopathology: June 2004 - Volume 26 - Issue 3 - p 230-233 Extraordinary Case Report Abstract Author Information We report a case of a 79-year-old Caucasian male who presented with a wrist lesion of combined intraepidermal Merkel cell carcinoma and squamous cell carcinoma in-situ. The two tumors were tightly admixed and distinct, and both were without any dermal or invasive components. No features of transition between the two tumors were seen. We suggest the term Merkel cell carcinoma in situ for tumors that demonstrate exclusive intraepidermal proliferation of neuroendocrine cells. From the *Department of Pathology and Laboratory Medicine and †Department of Dermatology, University of Cincinnati College of Medicine, Cincinnati, OH. Address correspondence and reprint requests to Diya F. Mutasim, MD, Department of Dermatology, 231 Albert Sabin Way, PO Box 670592, Cincinnati, OH 45267-0592 (e-mail: firstname.lastname@example.org). © 2004 Lippincott Williams & Wilkins, Inc.