Benign Eccrine Tumors Presenting on the Penis: Common Tumors at an Uncommon Site

Case 1 A 60-year-old Chinese man presented to the dermatology clinic with an asymptomatic, 0.5 × 0.5-cm erythematous papule on the penile shaft for a 2-year duration (Figure 1a). His medical problems consisted only of well-controlled hypothyroidism and hypertension. The initial clinical diagnoses considered were pyogenic granuloma or condyloma accuminatum. The excisional biopsy revealed a polypoidal lesion entirely covered by epidermis, with a proliferation of cuboidal, basaloid cells, consistent with an eccrine poroma (Figure 1b). Case 2 A 28-year-old Chinese man presented with an asymptomatic fusiform, 1.4 × 0.4-cm nodule over the ventral aspect of the prepuce, for a 10-year duration (Figure 2a). His medical history was otherwise unremarkable. Lymphangioma was the initial clinical diagnosis but biopsy results revealed large collapsed cystic spaces within the superficial dermis lined by a double layer of epithelial cells with eosinophilic cytoplasm, without evidence of decapitation secretion, consistent with an eccrine hidrocystoma (Figure 2b).