Extramammary Paget's Disease of External Genitalia with Bowenoid Features
A 79-year old man presented with painful erythematous patch and nodule on the external genitalia developed about 2 years ago. At a local clinic, he had been treated with topical steroid for one year, but showed no improvement. He was otherwise well, except asymptomatic inguinal hernia. There was also no history of internal malignancy.\nPhysical examination revealed an oozing erythematous patch spreading over the pubic area, scrotum, and penis. Further, a 1×1 cm-sized solitary moist and fragile nodule was on the scrotum (). Inguinal lymphadenopathy was not evident. Biopsy specimens were obtained from the patch and the nodule.\nOn microscopic examination, the patch showed large, round cells in the epidermis. Those cells were scattered discretely or grouped forming nests in the epidermis and showed pagetoid spreading (). These pagetoid cells had large nucleus and pale cytoplasm, and intercellular bridges between the cells were not seen. The basal cells beneath these cells were somewhat flattened (). Immunohistochemical stains for CEA, CK7, and CAM5.2 were expressed while the stains for CK20, HMB-45, S100, and P63 were completely negative (). Otherwise the nodule showed irregularly thickened epidermis, which had cells lying in complete disorder, resulting in 'wind-blown' appearance (). Many cells appeared highly atypical, showing large, hyperchromatic and pleomorphic nuclei and some of them showed atypical individual cell keratinization (). Immunohistochemical stains presented CEA+, CK7+, CAM5.2+ and CK20-, HMB-45-, S100-, P63- (). No other malignancy was found on workups, including radiologic examination. Finally, we diagnosed him as a primary EMPD with bowenoid features. He underwent total excisional surgery, and now he has been under observation with no recurrence so far.