Revisiting GDF9 variants in primary ovarian insufficiency: A shift from dominant to recessive pathogenicity?

BACKGROUND: Primary ovarian insufficiency (POI) affects around 2-4% of women before the age of 40. Genetic factors play an important role in POI. The GDF9 gene has been identified as a significant genetic contributor of POI. However, the pathogenicity and penetrance of GDF9 variants remain uncertain. METHODS: A next-generation sequencing approach was employed to investigate the entire coding region of the GDF9 gene in a cohort of 1281 patients with POI or diminished ovarian reserve (DOR). The frequency of each identified GDF9 variant was then compared with that of the general population, taking into account the ethnicity of each individual. RESULTS: By screening the entire coding region of the GDF9 gene, we identified 19 different variants, including 1 pathogenic frameshift variant. In total, 36 patients with POI/DOR (2.8%) carried at least one GDF9 variant. With regard to missense variants, no significant overrepresentation of the most common variants was observed in our POI/DOR cohort in comparison to the general or specific ethnic subgroups. Only one homozygous subject had a frameshift loss of function variant. CONCLUSION: This epidemiological study suggests that the vast majority of heterozygous missense variants could be considered as variants of uncertain significance and the homozygous loss-of-function variant could be considered as a pathogenic variant. The identification of a novel case of a homozygous POI patient with a heterozygous mother carrying the same variant with normal ovarian function strongly suggests that GDF9 syndrome is an autosomal recessive disorder.

Prognostic impact of thyroid dysfunctions on progression-free survival in patients with metastatic melanoma treated with anti-PD-1 antibodies.

This study aimed to assess the prognostic value of thyroid dysfunctions in metastatic melanoma patients on anti-programmed death-1 (anti-PD-1). A total of 110 stage IV or inoperable stage III melanoma patients treated with anti-PD-1 alone or in association with anti-CTLA-4 (T-lymphocyte antigen-4) antibody from January 2015 to December 2017 at our institution were enrolled in this retrospective study. Median follow-up was 32.8 months. Transitory thyroid dysfunctions and permanent thyroid dysfunctions were distinguished. The main criterion was progression-free survival. Secondary criteria were best response and overall survival. Survival curves were compared with log-rank tests and a cox proportional hazard ratio model was used to adjust patients and melanoma characteristics. Thirty-eight (35%) thyroid dysfunctions were observed during the follow-up, including 25 transitory thyroid dysfunctions (23%) and 13 permanent thyroid dysfunctions (12%). Progression-free survival was longer in patients with thyroid dysfunction (18.1 months) than in patients without thyroid dysfunction (3.9 months, P = 0.0085). In multivariate analysis, thyroid dysfunctions were not an independent predictive factor for progression-free survival. Patients with thyroid dysfunction had a longer overall survival (P = 0.0021), and thyroid dysfunctions were associated with a lower mortality risk (hazard ratio = 0.40; P = 0.005). Best response was positively associated with thyroid dysfunctions (P = 0.048). Thyroid dysfunctions induced by anti-PD-1 were not an independent predictive factor for progression-free survival in metastatic melanoma patients but seemed associated with a better response and increased overall survival.

Increased thyroid uptake on 18F-FDG PET/CT is associated with the development of permanent hypothyroidism in stage IV melanoma patients treated with anti-PD-1 antibodies.

PURPOSE: To determine performances of 2-deoxy-2-(18F)fluoro-D-glucose (18F-FDG) positron emission tomography (PET) to detect the development of permanent thyroid dysfunction (PTD), and to evaluate the prognostic value of early increased thyroid uptake in stage IV melanoma patients treated with anti-programmed death 1 (anti-PD-1) antibodies. METHODS: Twenty-nine patients were retrospectively enrolled. PTD was defined as symptomatic thyroid disorder requiring long-term specific treatment. On the first PET performed during follow-up, maximal standardized uptake value of the thyroid (SUVmax-Th) and SUVmax-Th/SUVmax-blood-pool ratio (Th/B) were measured. Areas under ROC curves (AUC) of these parameters for the diagnostic of PTD were compared. Cutoff values were defined to maximize the Youden's index. Survival analyses were performed according to the Kaplan-Meier method and compared using the log-rank method between patients with and without enhanced thyroid uptake according to cutoff values defined with the Hothorn and Lausen method. RESULTS: Four patients presented PTD. Median SUVmax-Th and Th/B were, respectively, 2.11 and 1.00. The median follow-up period was 21.7 months. AUC were 1.0 (CI95% 0.88-1.0) for both parameters. Optimal cutoff values were, respectively, SUVmax-Th > 4.1 and Th/B > 2.0, both conferring sensitivities of 100% (CI95% 40-100%) and specificities of 100% (CI95% 86-100%). The median progression-free survival and overall survival were 11.3 months and 33.5 months, respectively. Using optimized cutoffs, there was no statistically significant difference of survival. CONCLUSION: SUVmax-Th > 4.1 and Th/B > 2.0 provided perfect diagnostic performances to detect patients that developed PTD. No significant survival difference was found between patients with and without increased thyroid uptake.