A case of scrotal and penile extramammary Paget's disease (EMPD) and concurrent prostate adenocarcinoma in a 59-year-old patient is presented. Immunohistochemically, the tumor cells of both the EMPD and prostate stained positively for prostate-specific antigen. Six previously reported cases of EMPD associated with prostate adenocarcinoma are reviewed, along with a discussion of current theories of the pathogenesis of EMPD.