Trilogy Revisited: A Case Report of Co-Existing Nevus Sebaceous with Syringocystadenoma Papilliferum and Tubular Apocrine Adenoma

Nevus sebaceous of Jadassohn is a cutaneous hamartoma that is associated with various benign and malignant cutaneous tumors. Syringocystadenoma papilliferum and tubular apocrine adenoma are rare benign adnexal tumors. Simultaneous occurrence of all three tumors at the same site is extremely rare, which has raised several questions regarding their origin and pose a diagnostic challenge owing to considerable overlap in clinical and histological features. However, limited case reports have hindered our understanding of these tumors and their natural behavior. Herein, we report a case of a hairless scalp plaque in a 43-year-old male which on histological examination showed presence of syringocystadenoma papilliferum and tubular apocrine adenoma in the background of nevus sebaceous. We also made an attempt to review the available literature and understand the origin and look for clues to aid in accurate diagnosis of such tumors.