Eruptive Penile Syringomas Spreading to the Pubic Area and Lower Abdomen

Dear Editor: Syringomas are common benign neoplasms of eccrine differentiation. They often occur at the eyelids, upper cheeks, neck, axilla, abdomen and vulva. Penile syringomas are rare, with only 12 reported cases in the English literature to date. All of the reported cases were confined to the penis, and this is the first case of penile syringoma spreading to the pubic area and lower abdomen. A 33-year-old Korean male was presented to our clinic with asymptomatic papules on the pubic area, lower abdomen (Fig. 1A), as well as dorsal and lateral aspects of the penile shaft (Fig. 1B). The scrotum and glans were spared. The lesion occurred eruptively about 3 years ago. Physical examination found soft purplish papules measuring 1~3 mm in diameter on the penile shaft, pubic area and lower abdomen. He had no family history of similar lesions. Histologic examination of punch biopsies from the pubic area and penis revealed multiple comma or tadpole-shaped ductal structures and few milia-like structures within the superficial dermis (Fig. 2). The ductal structures were lined with 2- to 3-layered epithelial cells. The patient was diagnosed with eruptive syringomas of penis and pubic area. Fig. 1 (A) Small, soft, purplish papules on patient's penile shaft, (B) the pubic area and lower abdomen. Fig. 2 Multiple glandular structures lined by cuboidal epithelium in the dermis. Some tubular structures were comma or tadpole shaped. (A) Suprapubic area (H&E, ×200), (B) penile shaft (H&E, ×100). Syringomas are benign tumors of eccrine glands often occurring in adolescence or young adults with female predominance1. It usually presents as multiple, small, fresh-colored to brownish papules or coalesced plaques with predilection for the eyelids, neck, chest, axilla and vulva. Involvement of the penis is uncommon, and only 12 cases have been reported in English literature to date. All of the reported penile syringomas were presented on the shaft of the penis, not the scrotum or pubic area. An exact pathogenesis of syringoma is still unknown, but the neoplastic process, reactive hyperplasia, an association with hormonal factors is considered to be an etiologic factor2,3. Eruptive syringomas consist of the successive development of multiple papules in a limited area were thought to be a reactive process4. Although vulvar syringomas are not rare, penile syringomas are uncommon and all reported cases were restricted on the penis. Succesive development of syringomas on the penis and pubic area could suggest its reactive nature other than other factors. The differential diagnosis of penile syringomas includes genital warts, lichen planus, bowenoid papulosis, angiokeratoma, angiofibroma, granuloma annulare, lichen nitidus, sarcoidosis, pearly penile papules, calcinosis cutis, and so on3. Treatment is necessary only for cosmetic causes. Surgical excision, electrodessication and curettage, chemical peels, cryosurgery, laser treatment with a carbon dioxide laser or a carbon dioxide fractional laser were reported to be effective5. In summary, we report a patient with eruptive penile syringomas spreading to the pubic area and lower abdomen. Penile syringomas are a rare presentation and are usually confined to the penile shaft only, and this is the first case of penile syringoma spreading to the pubic area and lower abdomen.