The clinical phenotype of SDHC-associated hereditary paraganglioma syndrome (PGL3)

Context: Mutations in the genes encoding subunits of the succinate dehydrogenase complex cause hereditary paraganglioma syndromes. Although the phenotypes associated with the more commonly mutated genes, SDHB and SDHD, are well described, less is known about SDHC-associated paragangliomas. Objective: To describe functionality, penetrance, number of primary tumors, biological behavior, and location of paragangliomas associated with SDHC mutations. Design: Families with an SDHC mutation were identified through a large cancer genetics registry. A retrospective chart review was conducted with a focus on patient and tumor characteristics. In addition, clinical reports on SDHC-related paragangliomas were identified in the medical literature to further define the phenotype and compare findings. Setting: A cancer genetics clinic and registry at a tertiary referral center. Patients: Eight index patients with SDHC-related paraganglioma were identified. Results: Three of the eight index patients had mediastinal para...