CME ArticleRole of Immunohistochemistry in Diagnosing Tumors of Cutaneous AppendagesHoang, Mai P MDAuthor Information Associate Professor of Pathology, Harvard Medical School' Staff Dermatopathologist, Massachusetts General Hospital, Boston, MA. The author and staff in a position to control the content of this CME activity and their spouses/life partners (if any) have disclosed that they have no financial relationships with, or financial interests in, any commercial organizations pertaining to this educational activity. Reprints: Mai P. Hoang, MD, Department of Pathology, Massachusetts General Hospital, 55 Fruit Street, Warren 820, Boston, MA 02114 (e-mail: [email protected]). The American Journal of Dermatopathology: December 2011 - Volume 33 - Issue 8 - p 765-774 doi: 10.1097/DAD.0b013e31820a4837 Buy CME Test Metrics Abstract In recent years, there has been significant progress in immunohistochemistry as an ancillary tool in diagnostic dermatopathology. In most instances, the histologic diagnosis can be rendered with the routine histologic sections; however, immunohistochemistry can help to narrow the differential in diagnosing neoplasms of cutaneous appendages in some settings including adnexal versus epidermal origin, benign versus malignant adnexal neoplasms, and primary adnexal carcinoma versus cutaneous metastases as outlined in this review. © 2011 Lippincott Williams & Wilkins, Inc.