Genetic evaluation of patients and families with concern for hereditary endocrine tumor syndromes.

Hereditary endocrine tumor syndromes are rare conditions with overlapping features. It is imperative that healthcare providers differentiate between these syndromes for proper patient care. Advances in genetic testing technologies have increased utilization of genetic counseling and testing in this field; however, few endocrine cancer genetics clinics exist. Two years ago, a genetic counselor (GC) specializing in endocrine cancer genetics was added to the multidisciplinary team of the James Neuroendocrine/Thyroid Clinic at The Ohio State University. Here, we report on this experience. In total, 358 patients were seen. The majority were referred by medical oncology (n = 204; 57%) for a personal history of disease (n = 249; 81%). The most common referral indications were pancreatic neuroendocrine tumors (n = 44; 17%), multiple primary tumors (n = 37; 14%), and pheochromocytoma/paraganglioma (n = 35; 14%). Most patients completed genetic testing after genetic counseling (n = 200; 65%). Targeted gene panel testing was the most common testing ordered (n = 98; 32%). Thirty-one patients (15.5%) had ≥ one likely pathogenic variant (LPV) or pathogenic variant (PV) identified. Approximately 37% (n = 11) did not meet genetic testing guidelines for the gene they tested positive for. The most common genes with LPV/PVs were the SDH genes (n = 8) and MEN1 (n = 7). Referral indications with the highest likelihood of LPV/PVs were paraganglioma, medullary thyroid carcinoma, and multiple primary tumors. We believe this data can provide valuable guidance to healthcare providers who see patients with endocrine neoplasia or who are seeking to establish hereditary endocrine cancer clinics.