Genetic testing in head and neck paraganglioma: who, what, and why?

Background Genetic testing in head and neck paragangliomas (HNPG) can have profound implications in patient and family counseling. Methods Retrospective review was performed of patients with HNPG at a cancer care center from 1970 to present. Patient demographics, disease patterns, outcomes, and genetic mutations were analyzed. Results We identified 26 patients with available genetic testing results. Sixteen had mutations. Succinate dehydrogenase gene, sub unit D (SDHD) accounted for 75% of mutations, of which P81L accounted for 75%. The remainder had SDHB mutations. Patients with mutations were younger (average age 39.5 years versus 48.4 years), 63% (versus 40%) had multiple tumors, 94% (60%) had at least one carotid body tumor, and family history was positive in 38% (20%). Conclusion Patients suspected of heritable HNPG should undergo testing first at the SDHD and SDHB loci, and those with younger age, multiple tumors, carotid body tumors, and positive family history are more likely to have mutations.