Pigmented extramammary Paget's disease of the axilla mimicking melanoma: case report and review of the literature

Abstract

Pigmented Paget's disease is a rare variant that is often confused clinically and histologically with melanoma in situ. Herein, we describe a case of pigmented extramammary Paget's disease involving the axilla of a 79‐year‐old white male thought initially to represent malignant melanoma clinically and histologically. Review of the literature reveals that pigmented variant of Paget's disease, either mammary or extramammary, could be initially misdiagnosed as melanoma unless this entity is considered in the differential diagnosis, and additional confirmatory studies are performed.

Extramammary Paget's disease involving the penis, scrotum and the axilla

“…5 HMB-45, S100, MART1 and MITF are melanocytic markers but uniformly negative for Paget's cells. 6 T-cell markers including CD3, UCHL-1 are positive in mycosis fungoides but not in EMPD. 5 The incidence of an associated underlying malignancy has been reported to vary and it depends on the anatomic sites affected.…”

Cutaneous Malignancies of the Perineum

“…There is also a pigmented variant of this disease that may be mistaken for melanoma. 7 A tissue biopsy is essential to making the diagnosis of EMPD, considering the broad clinical differential diagnosis. Any treatment-resistant dermatosis of the perineum should be biopsied to rule out a neoplastic etiology.…”

Extramammärer Morbus Paget – Klinik, Histogenese, Therapiemöglichkeiten

“…Die Primäreffloreszenz des EMP ist ein scharf begrenzter roter Fleck (Abbildungen 1 und 2). Nur in Einzelfällen wurden de-oder hyperpigmentierte Makulae beobachtet [30,31]. Das Erythem ist durch rosa, hell-bis dunkelrote oder rot- abgesehen enthalten PZ einen hohen Muzinanteil, der sich je nach Zusammensetzung der Mucopolysaccharide mit der PAS-oder der Alcianblaufärbung darstellen lässt.…”

“…Histopathologisch sollte ebenfalls die benigne muzinöse Metaplasie ausgeschlossen werden. Die Mycosis fungoides, das maligne Melanom und das intertriginöse Basalzellkarzinom sind differenzialdiagnostisch ebenfalls zu berücksichtigen [30,49]. Als Rarität muss die Manifestation des EMP am Kapillitium in Form eines kreisrunden Haarausfalls angesehen werden [32].…”