This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Extramammary Paget disease (EMPD) is characterized by a chronic eczema-like rash of the skin around the genital regions of males and females. Under the microscope, this condition looks very similar to a condition that occurs on the breast called mammary Paget disease. The primary difference between the two is the location of the rash. While the location of the rash for individuals with mammary Paget disease is around the nipple and areolar skin, EMPD may occur in the vulva, perianal region, scrotum, penis, and axilla. EMPD most often occurs in women between age 50 to 60. About 25 percent of extramammary Paget disease is associated with an underlying cancer. Treatment typically includes surgery. Prognosis varies depending on how early the disorder was diagnosed and treated as well as the association with an underlying cancer. 
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