SHORT COURSE

Friday Morning - March 4, 8:00 AM - 12:00 Noon





59. Non-Melanocytic Mimics of Melanoma: Problems in Differential Diagnosis

Thomas Brenn, M.D., Ph.D, FRCPath, Western General Hospital and The University of Edinburgh, Edinburgh, Scotland, and Jason L. Hornick, M.D., Ph.D, Brigham and Women's Hospital and Harvard Medical School, Boston, MA

The correct diagnosis of melanoma can be a serious challenge even to the experienced pathologist, largely due to its broad morphological spectrum. This practical course will provide a comprehensive review of non-melanocytic tumors to be considered in the differential diagnosis of melanoma including epithelial, mesenchymal, and hematolymphoid neoplasms. Particular emphasis will be placed on the integration of clinical findings and histologic features, as well as the appropriate, directed use of immunohistochemistry in differential diagnosis. The course is suitable for a wide audience and will be especially beneficial to senior residents in pathology and fellows in dermatopathology, as well as general surgical pathologists and dermatopathologists in practice.

The course will be structured around 10 specific cases. Each case presentation will lead into a more general discussion of the entities in the differential diagnosis. In particular, each of the individual cases will be a close mimic of certain features of melanoma. The discussion will be organized to address the differential diagnosis of: 1) in situ melanoma, 2) epithelioid melanoma, 3) spindle cell melanoma, 4) desmoplastic melanoma, 5) small cell melanoma, and 6) S-100 immunopositivity.

Virtual slides corresponding to the 10 cases will be posted on the USCAP web site for review by pre-registrants prior to the meeting, along with a multiple choice-type questionnaire containing 1-2 questions about each case. After viewing the cases and formulating a diagnostic opinion, the participants will be asked to complete the questionnaire; the anonymous results will be discussed during the course. A syllabus will be distributed to registrants at the meeting. Registrants will receive web access to the PowerPoint presentation given at the Annual Meeting along with the text portion of the syllabus after the meeting.

Upon completion of the course, the participants will be familiar with the spectrum of non-melanocytic tumors in the differential diagnosis of melanoma and their salient histological and immunohistochemical features. In particular, they will be comfortable interpreting these features in the appropriate clinical context.

This course may be used for CME credits or SAM credits.