Background: Extramammary Paget's disease (EMPD) most commonly occurs in the perineal and genital areas of elderly people. The current treatment of choice is adequate surgical excision.
Materials and methods: Between 1990 and 2007, 28 patients (27 men and one woman) with EMPD were treated at Asan Medical Center, Seoul, Korea, by wide local excision (WLE) with a 2- to 3-cm normal skin margin. "Carcinoma in situ" (CIS) was defined as confinement of Paget cells to the epithelium, whereas "invasive carcinoma" was defined as infiltration of Paget cells into more than dermal connective tissue.
Results: Of the 28 lesions, 21 (75%) were located in the penoscrotal area. Six (21.4%) patients had associated gastrointestinal neoplasms, three with associated gastrointestinal malignancies and four with synchronous colorectal adenomas, including one with both. Surgical procedures included WLE with primary repair in 13 patients (46.4%), WLE with skin graft in 12 (42.9%), WLE with skin graft and Gracilis muscle transposition in two (7.1%), and combined abdominoperineal resection and distal gastrectomy in one (3.6%). Four patients (14.3%) also underwent inguinal lymph node dissection, with three found to have lymph node metastases. Of 11 patients with invasive carcinoma, three (27.3%) had lymph node metastases, compared with none of 17 patients with CIS. Patients with lymph node metastases showed a significantly lower disease-specific survival rate (P = 0.008). Patients with invasive carcinoma tended to have a lower disease-specific survival rate (P = 0.087).
Conclusions: EMPD in Korea showed an absolute male predominance and an association with gastrointestinal neoplasms. Lymph node metastasis significantly affected, and depth of invasion tended to affect, disease-specific survival rate.