Sebaceous Adenoma in a Patient With Visceral Malignancies
A 71-year-old man with a past medical history of early-onset colorectal, urothelial, and prostate cancers presented with a 13 × 8 mm2 left lower lid papillary-appearing lesion. He first noticed eye burning, itching, and a palpebral conjunctival mass 2 months prior to presentation (Fig A). Family history was significant for 3 first-degree relatives with early-onset colorectal cancers. Excisional biopsy was performed and subsequent H&E staining showed predominantly mature sebaceous cells with rare immature cells. Mitotic figures and cellular atypia were not seen (Fig B). Immunohistochemical staining demonstrated microsatellite instability (MSI), with loss of MSH2 and MSH6 while retaining MLH1 and PMS2. MSI and insignificant cellular atypia were consistent with the diagnosis of sebaceous adenoma. The constellation of pathologic findings and the patient’s clinical history and family history were in agreement with a diagnosis of Muir-Torre syndrome. Muir-Torre syndrome is an autosomal dominant syndrome that is a clinical subtype of hereditary nonpolyposis colorectal cancer, which is caused by a germline mutation in the DNA mismatch repair genes (MSH2, MLH1, PMS2, and less commonly MSH6). It is characterized by at least 1 visceral malignancy and 1 cutaneous lesion such as a sebaceous tumor or a keratoacanthoma. At the patient’s 6-month follow-up visit, his eyelid was completely healed without signs of recurrence. This case highlights the importance of screening for sebaceous tumors and keratoacanthomas in patients with history suggestive of probable Muir-Torre syndrome.© 2020 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.