Atypical Periocular Lesions: Muir–Torre Syndrome

A 63-year-old male presented with a rapidly enlarging right lower lid mass for 1 year (Fig. 1A). Three principal ulcerated lesions were observed on the right lower lid (Fig. 1A), the right brow (Fig. 1A), and the left cheek (Fig. 1B). Pathological examination identified the right lower lid and left cheek lesions as sebaceous carcinoma, and the right brow lesion as squamous cell carcinoma in situ. Although ocular adnexal sebaceous carcinoma secondary to Muir–Torre syndrome (MTS) is rare, the existence of 2 separate sebaceous lesions warranted further screening. Immunohistochemistry identified the largest lesion on the right lower lid as a sebaceous carcinoma with microsatellite instability (Fig. 2A) atypical basophilic cells with variably pleomorphic, prominent nucleoli, and foamy cytoplasm consistent with sebaceous carcinoma; (Fig. 2B–D) immunohistochemistry with MSH2-positive, MSH6-positive, and MLH1-negative tumor cells, respectively, consistent with MTS. Further systemic screening was pursued with identification of scattered pulmonary nodules concerning for metastases. Unfortunately, the patient was lost to follow up after one round of neoadjuvant chemotherapy, with C1 carboplatin and paclitaxel, to reduce tumor burden. MTS is a variant of Lynch syndrome typically due to autosomal dominant mutations in DNA mismatch repair genes (e.g., MSH2, MSH6, and MLH1) and is most commonly associated with colorectal, urogenital, and head and neck cancers. Patients should be screened annually for colorectal and urogenital cancer screenings. Physicians should be aware that although MTS is rarely associated with ocular adnexal sebaceous carcinoma, presence of multiple sebaceous lesions or visceral malignancies warrants further evaluation for MTS.FIG. 1FIG. 2