Extramammary Paget Disease: A Review of the Literature-Part I: History, Epidemiology, Pathogenesis, Presentation, Histopathology, and Diagnostic Work-up

BACKGROUND Extramammary Paget disease (EMPD) is a rare malignancy with unclear pathophysiology that occurs predominantly on apocrine rich skin. Surgery is the treatment of choice; however, procedures tend to be extensive and associated with a high rate of recurrence. OBJECTIVE To review the current literature on EMPD regarding epidemiology, pathogenesis, clinical presentation, histology, diagnostic work-up, treatment, and prognosis. MATERIALS AND METHODS Literature review using PubMed search for articles related to EMPD. RESULTS Extramammary Paget disease classically presents as a slowly growing red plaque, which often mimics an inflammatory condition leading to significant delay in diagnosis. Diagnosis requires histopathologic examination and is often supported by immunohistochemical analysis. Once a diagnosis of EMPD is made, the patient must be risk-stratified and evaluated for an underlying malignancy. CONCLUSION Standard of treatment is surgery, with data suggesting that Mohs micrographic surgery may have superior clinical outcomes and lower recurrence rates. Alternatives such as photodynamic therapy and topicals have been explored and may be appropriate in certain situations. Patients with EMPD generally have a good prognosis with a 5-year overall survival rate of 75% to 95%.