Well-differentiated Squamous Cell Carcinoma Arising in Syringocystadenoma Papilliferum.

Syringocystadenoma papilliferum (SCAP) is a hamartoma of apocrine sweat gland origin, occurring predominantly in children, in the head and neck region. SCAP can arise or coexist with both benign and malignant tumors. We report herein an extremely rare case of squamous cell carcinoma (SCC) arising in SCAP growth located in unusual supragluteal region in an elderly Indian male. A wide surgical excision of the growth was performed which upon histopathological examination revealed the confirmatory diagnosis. SCC arising in SCAP is unusual, and only two histologically confirmed cases have been previously reported in the literature. This case report emphasizes about extremely rare malignant transformation of SCAP, which should be kept in mind while evaluating a suspicious skin lesion.