SDHx gene detection and clinical Phenotypic analysis of multiple paraganglioma in the head and neck.

Objectives The goal of this study was to detect and explore the mechanisms of the succinate dehydrogenase (SDH) complex subunit-related gene mutations in cases of multiple paraganglioma (PGL) in the head and neck. Methods In Beijing Tongren Hospital (Capital Medical University, Beijing, People's Republic of China) between January 2013 and February 2017, 23 cases of head and neck multiple PGL were evaluated by genetic sequencing. From these cases, four hereditary families and 10 cases with sporadic occurrences were found. Gene mutations, including SDHD, SDHB, SDHC, SDHAF2, VHL and RET in germ cells and somatic cells, were detected by gene capture and high throughput sequencing. Results In family 1, 12 instances of SDHD gene mutation were detected, eight of which manifested as bilateral carotid body tumor (CBT) with one bilateral malignant CBT. In family 2, three cases of SDHD mutation were found with one case of bilateral CBT and two cases of unilateral CBT. In family 3, two cases of SDHD gene mutation were found, both characterized by vagus PGL and pheochromocytoma. Of the 10 patients with sporadic manifestations, five cases of SDHD gene mutation and one case of RET gene mutation were detected. Two novel gene mutations, c.387_393del7 mutation of SDHD gene and c.3247A>G mutation of RET gene, were also detected. Conclusion In patients with multiple PGL in the head and neck, these are accompanied by a genetic mutation of the germ cell. In this case study, this mutation was most commonly a mutation of the SDH gene.