A case of extramammary Paget's disease with underlying anal carcinoma of a 52-year-old female patient is presented in this study.
She had pruritis around her perianal skin 15 years ago. The histological exammination then revealed presence of anal Paget's disease, and she received the electron beam therapy. Ten years later, the recurrence of Paget's disease was observed. But there was no evidence of anal carcinoma by romanoscopic exammination. When she visited us, the histological exammination showed that Paget's cells invaded the dermis, and signetring cell were present within the epidermis. Immunohistochemical staining of the Paget's cells by monoclonal anti-CEA was positive. The electron microscopic study revealed that Paget's cells posessed mucinous secretory vacuoles.
It was diagnosed, therefore, as carcinoma in situ, according to the classification of Ohyama, whose cells originated from either epithelium of anal gland or mucinous gland, and later developed into the anal carcinoma as a result of infiltration of lamina propria.
