How do I diagnose Pagetoid Bowen Disease

Abstract

Bowen disease is a variant of squamous carcinoma in situ, which sometimes presents with a pagetoid growth pattern with cytologically atypical clear cells. In that case, the differencial diagnosis includes Paget disease and melanoma in situ, as well as less common entities. Here we describe a case where histological differenciation is difficult and immunohistochemical studies are necessary to make a diagnosis. Here we also highlight the heterogeneity of CK7 expression and the apparent specific expression of p63 in Pagetoid Bowen Disease.