Syringocystadenocarcinoma Papilliferum In Situ, a Variant of Cutaneous Adenocarcinoma In Situ: A Case Report With Literature Review.

Syringocystadenocarcinoma papilliferum in situ, a variant of cutaneous adenocarcinoma in situ, is extremely rare. Only 9 cases have been published to date with 2 cases demonstrating pagetoid epidermal involvement. In this study, we report a case of syringocystadenocarcinoma papilliferum in situ with pagetoid epidermal involvement arising from a long-standing nevus sebaceus on the scalp of a 60-year-old woman.