Genetic Drivers in Sebaceous Neoplasms: A Review of Germline and Somatic Mutations and Their Role in Treatment and...

Background: The efficacy of germline testing in colorectal cancer has been proven; however, germline testing in individuals with sebaceous neoplasms is less well defined. This review aims to summarize the literature on sebaceous neoplasms to date, describing the somatic tumor profiles, tumor screening methods, and personal and family history that are suspicious of a germline mutation. Sebaceous neoplasms can be attributed to a variety of etiologies, including UV exposure, immunodeficiency, germline mutations, or multifactorial influences associated with aging. Sebaceous tumors with abnormal microsatellite instability and mismatch repair deficiency are indicative of a germline mutation in 20-50% of cases, which is similar to rates found in colorectal tumors. Personal and familial history can also be suggestive of a germline etiology in these patients and should be assessed routinely, as approximately 30% of individuals with sebaceous neoplasms carry a germline mutation. We outline a strategy for the identification of individuals at risk for germline mutations, recommendations for the management of mutation carriers, and treatment options for individuals with sebaceous neoplasms. Conclusions: Sebaceous tumors are most often sporadic; however, evaluations of a germline etiology are prudent to effectively identify those at risk of additional malignancies as well as at-risk family members. Referral to genetic counseling and germline genetic testing for individuals at risk can significantly impact cancer treatment and screening in patients and their families.