Extramammary Paget's disease (EMPD) is a rare intraepidermal carcinoma that predominantly involves apocrine gland-bearing areas such as vulva, scrotum, and perianal regions as well as axillae. It is subdivided into primary and secondary EMPD based on whether there is an underlying malignancy, such as adenocarcinoma of skin appendage or noncutaneous carcinoma. The majority of primary cases are confined to the epidermis, but the incidence of dermal invasion has been reported to be as high as 18.8%.1 Dermal invasion is significantly associated with lymph node metastasis, distant metastasis, and poor prognosis.1, 2
Primary triple extramammary Paget's disease (TEPD) represents a very rare condition where the simultaneous occurrence of EMPD is noticed over bilateral axillae and the genital region. To our knowledge, case series of TEPD have been mostly reported in Japan,3, 4 and TEPD in other races is extremely rare.5 The clinical course and prognosis of this rare disease are still unclear owing to the small number of reported cases and heterogeneous entities.3, 5, 6 Herein, we present a case with primary invasive TEPD and review the literature. To our knowledge, this is the first Taiwanese TEPD case to be presented.
A 70-year-old man attended our dermatology clinic with a 6-year history of an erythematous plaque on the left armpit and a 5-year history of reddish plaques on bilateral groins and scrotum. He had previously received topical antifungal agents and topical corticosteroid for these skin lesions for 3 years in a local hospital with poor response. Moreover, cryotherapy over whole skin lesions every 1–3 weeks has also been given for about 1 year. Initially, the cryotherapy showed some clinical improvement over focal skin lesions, which healed with scaring and pigmentary change clinically, but skin lesions recurred and progressed under treatment later. During the entire treatment course, this patient did not undergo any investigation for the histopathologic examination. Owing to the progression of the disease under the aforementioned treatment, he was referred to our clinic. Dermatology findings revealed an erythematous confluent erosive plaque over the base of the penis, the left side of the scrotum, and the left inguinal area.