Pigmented epithelioid melanocytoma: favorable outcome after 5-year follow-up

• Published in: The American journal of surgical pathology Vol. 33; no. 12; p. 1778
• Main Authors: Mandal, Rajni V, Murali, Rajmohan, Lundquist, Kurt F, Ragsdale, Bruce D, Heenan, Peter, McCarthy, Stanley W, Mihm, Jr, Martin C, Scolyer, Richard A, Zembowicz, Artur
• Format: Journal Article
• Language: English
• Published: United States 01.12.2009
• Subjects: Adolescent; Adult; Aged; Australia; Biopsy; Child; Child, Preschool; Disease-Free Survival; Epithelioid Cells - pathology; Female; Follow-Up Studies; Humans; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Invasiveness; Neoplasm Staging; Nevus, Blue - secondary; Nevus, Blue - surgery; North America; Skin Neoplasms - secondary; Skin Neoplasms - surgery; Time Factors; Treatment Outcome; Young Adult; Australia; North America
• ISSN: 1532-0979
• DOI: 10.1097/pas.0b013e3181b94f3c

Pigmented epithelioid melanocytoma (PEM) is a recently described entity encompassing epithelioid blue nevus (of Carney complex) and most tumors earlier considered as so-called "animal-type melanoma". Loss of expression of a Carney complex gene, cyclic adenosine 3',5' monophosphate-dependent protein kinase regulatory subunit 1alpha, is observed in the majority of PEMs. Initial reports with short-term follow-up have suggested that although PEMs frequently metastasize to lymph nodes, they have a more favorable outcome than conventional melanomas. In this report, we present the results of long-term follow-up in 26 patients with PEMs from North America and Australia. There were 9 males and 17 females, with a median age of 20 years. The tumors involved the trunk (6 cases), extremities (12 cases), genitalia (1 case), and the head and neck region (7 cases) had a median Breslow thickness of 2.2 mm (range 0.80 to 10.0 mm) and a median Clark level of 4. Eight of the patients developed lymph node metastases. After a median follow-up period of 67 months (range 39 to 216 mo), all patients are alive and free of disease. These findings provide further evidence that PEM is a unique low-grade melanocytic tumor with limited metastatic potential (to lymph nodes), but a favorable long-term clinical course.