Extraocular Sebaceous Carcinoma in a Patient With Muir-Torre Syndrome

BACKGROUND Sebaceous carcinoma (SC) is a rare, aggressive neoplasm arising from the adnexal epithelium of sebaceous glands and is commonly associatedwithMuirYTorre syndrome (MTS), an autosomal-dominant genodermatosis. MTS is characterized by sebaceous neoplasms, keratoacanthomas, and a high incidence of internalmalignancies (Okan, Vural, Ince, Yazar, Uras, & Saruc, 2012; Ponti& Ponz de Leon, 2005). Identification of these rare cutaneous findings warrants a thorough evaluation and work-up for these associated systemic findings. SCis of unknown etiology and has increased prevalence among elderly individuals and Caucasians and a slight predominance among men (Harrington, Egbert, & Swetter, 2004; Torres, Amorim, Hercules, & Kac, 2012). It can be classified as either ocular SC or extraocular SCdepending on the involvement of the eyelid structures. Ocular SC represents 75% of all SCs, with themeibomian gland as the site of origin for approximately half of these cases (Cieza-Diaz, CanoMartinez, Barchino-Ortiz,& Longo-Imedio, 2012; Okan et al., 2012). The most frequent localization for the remaining25% of extraocular SCcases is the head and neck because of a high concentration of sebaceous glands; however, the tumor can arise from any site where sebaceous glands are present (Berlin, Amin,& Goldberg, 2008; Torres et al., 2012).