No evidence for increased mortality in SDHD variant carriers compared with the general population

Germline variants in subunit D of the succinate dehydrogenase gene (SDHD variants) are associated with an increased risk of developing paragangliomas. The aim of this study was to compare mortality rates and survival in a Dutch cohort of SDHD variant carriers with those in the general population. The study was conducted at the Leiden University Medical Center, a tertiary referral center for patients with paragangliomas. Included subjects all tested positive for SDHD variants before 1 July 2012 and visited the departments of Otorhinolaryngology or Endocrinology at least once or had a diagnosed paraganglioma and a SDHD variant-positive family history. Clinical data were retrieved from medical records, information on mortality was obtained from the Municipal Personal Records Database, and mortality rates for the Dutch population were obtained from the Dutch Central Bureau of Statistics, stratified by sex, age and date. SDHD variant carriers were followed from the date of first SDHD variant-related contact until death, emigration or 12 December 2012 and the standardized mortality ratio (SMR) was calculated. Two-hundred and seventy-five SDHD variant carriers were included in the study, of which 80% carried the c.274G>T, p.(Asp92Tyr) variant, had a mean duration of follow-up of 7.6 years, yielding 2242 person-years of observation for analysis. There were 18 deaths in the SDHD variant carrier group; two were paraganglioma related. The SMR for the whole cohort was 1.07 (95% confidence interval 0.67–1.73). In conclusion, mortality in SDHD variant carriers is not substantially increased. Additional studies are required to confirm these findings

Increased mortality in SDHB but not in SDHD pathogenic variant carriers

Germline mutations in succinate dehydrogenase subunit B and D (SDHB and SDHD) are predisposed to hereditary paraganglioma (PGL) and pheochromocytoma (PHEO). The phenotype of pathogenic variants varies according to the causative gene. In this retrospective study, we estimate the mortality of a nationwide cohort of SDHB variant carriers and that of a large cohort of SDHD variant carriers and compare it to the mortality of a matched cohort of the general Dutch population. A total of 192 SDHB variant carriers and 232 SDHD variant carriers were included in this study. The Standard Mortality Ratio (SMR) for SDHB mutation carriers was 1.89, increasing to 2.88 in carriers affected by PGL. For SDHD variant carriers the SMR was 0.93 and 1.06 in affected carriers. Compared to the general population, mortality seems to be increased in SDHB variant carriers, especially in those affected by PGL. In SDHD variant carriers, the mortality is comparable to that of the general Dutch population, even if they are affected by PGL. This insight emphasizes the significance of DNA-testing in all PGL and PHEO patients, since different clinical risks may warrant gene-specific management strategies

Primary Hyperparathyroidism in MEN1 Patients A Cohort Study With Longterm Follow-Up on Preferred Surgical Procedure and the Relation With Genotype

Item does not contain fulltextOBJECTIVE: To identify the optimal surgical strategy for multiple endocrine neoplasia type 1 (MEN1)-related primary hyperparathyroidism (pHPT). To describe the course of postoperative hypoparathyroidism and to assess whether genotype is associated with persistent/recurrent pHPT. BACKGROUND: Surgery is the preferred treatment in MEN1-related pHPT, but the surgical procedure of choice is still uncertain. METHODS: This retrospective cohort study was performed at the Departments of Endocrinology of the University Medical Centers of Utrecht and Nijmegen, the Netherlands. Patients were selected from the Dutch MEN1 database, including all patients 16 years or older treated for MEN1 from 1990 to 2009. Data were collected by medical record review. RESULTS: Seventy-three patients underwent parathyroid surgery. Persistent/recurrent pHPT occurred in 53% after less than 3 parathyroids resected (/=6 months) postoperative hypoparathyroidism occurred in 24% after <SPTX, 39% after SPTX, and 66% after TPTX. Median duration of hypoparathyroidism was 1.5 years, in 65% successful cessation of vitamin D/calcium was possible, even after more than 10 years. After <SPTX, patients with nonsense or frameshift mutations in exons 2, 9, and 10 had a significantly lower risk of persistent/recurrent pHPT than patients with other mutations. After SPTX/TPTX persistence/recurrence did not differ with genotype. After SPTX/TPTX persistence/recurrence was more frequent (P = 0.07) in patients without bilateral transcervical thymectomy (TCT). CONCLUSIONS: SPTX with bilateral TCT is the procedure of choice for MEN1-related pHPT. Genotype seems to affect the chance of recurrence. Postoperative hypoparathyroidism lasting 6 months or more should not be considered permanent in MEN1.1 juni 201