Progression of intraepithelial Paget's disease of the vulva to invasive carcinoma.

Sequential progression from intraepithelial Paget's disease of the vulva to invasive carcinoma after an interval of 10.8 years is documented in this report. Infiltration of the dermis with permeation of lymphatics and metastasis to regional lymph nodes are believed to have resulted directly from foci of intraepidermal Paget's cells that persisted after a simple vulvectomy. No underlying primary sweat gland carcinoma was present. Hence, this case establishes the invasive potential of intraepithelial vulvar Paget's disease and substantiates the notion that it is indeed a type of carcinoma in situ.