Endocrine Abstracts

Introduction: Paragangliomas are rare tumors originated from extraadrenals chromaffin cells. Most are sporadic, but between 30% and 50% are associated with hereditary syndromes. Mutations in the succinate gene dehydrogenase (SDH) have been identified as a cause of the hereditary paraganglioma-pheochromocytoma syndrome.

Material and methods: Descriptive study of case series of patients belonging to the Southern Health Area of Seville with mutations in the SDH gene associated with hereditary paraganglioma syndrome.

Results: There were 22 patients belonging to four different families, who were carriers of genetic mutations in SDH gene. 27.27% (6/22) of them have developed tumors related to these genetic variants. Median age of patients at diagnosis of tumors was 35 years. The heterozygous mutation in exon 2, c.79>T of the SDHB gene was the most frequent, affecting 45.45% (10/22) patients; 3/10 of them (33.33%) presented paraganglioma and 1/10 adrenal hyperplasia. On the other hand, c.293G>A mutation in SDHB gene affected to 5/22 patients (22.72%); 1/5 of them presented paraganglioma. Thirdly, c.761C>T mutation in the SDHB gene affected to 4/22 patients (18.18%); 1/4 of them presented paraganglioma. Lastly, c.1A>G mutation in SDHC gene affected 3/22 patients (13.63%); 1/3 of them developed paraganglioma. All cases were asymptomatic. None was functional and only 1 case presented slightly increased levels of chromogranin A. All cases required surgical treatment and only 1 needed chemotherapy.

Conclusions: – Despite its rarity, we should not forget to include paraganglioma in the differential diagnosis of patients with compatible symptoms.

– Once diagnosed, it is essential to consider genetic tests in order to establish a possible hereditary origin.

– If the hereditary origin is confirmed, it should be considered to extend the study to relatives to diagnose more cases and to supervise carriers of the mutation.