Metachromatic leukodystrophy genotypes in The Netherlands reveal novel pathogenic ARSA variants in non-Caucasian patients

Metachromatic leukodystrophy (MLD) is an autosomal recessively inherited sulfatide storage disease caused by deficient activity of the lysosomal enzyme arylsulfatase A (ASA). Genetic analysis of the ARSA gene is important in MLD diagnosis and screening of family members. In addition, more information on genotype prevalence will help interpreting MLD population differences between countries. In this study, we identified 31 different ARSA variants in the patient cohort (n = 67) of the Dutch expertise center for MLD. The most frequently found variant, c.1283C > T, p.(Pro428Leu), was present in 43 (64%) patients and resulted in a high prevalence of the juvenile MLD type (58%) in The Netherlands. Furthermore, we observed in five out of six patients with a non-Caucasian ethnic background previously unreported pathogenic ARSA variants. In total, we report ten novel variants including four missense, two nonsense, and two frameshift variants and one in-frame indel, which were all predicted to be disease causing in silico. In addit

Should jaundice preclude resection in patients with gallbladder cancer? Results from a nation-wide cohort study

Background: It is controversial whether patients with gallbladder cancer (GBC) presenting with jaundice benefit from resection. This study re-evaluates the impact of jaundice on resectability and survival. Methods: Data was collected on surgically explored GBC patients in all Dutch academic hospitals from 2000 to 2018. Survival and prognostic factors were assessed. Results: In total 202 patients underwent exploration and 148 were resected; 124 non-jaundiced patients (104 resected) and 75 jaundiced patients (44 resected). Jaundiced patients had significantly (P < 0.05) more pT3/T4 tumors, extended (≥3 segments) liver- and organ resections, major post-operative complications and margin-positive resection. 90-day mortality was higher in jaundiced patients (14% vs. 0%, P < 0.001). Median overall survival (OS) was 7.7 months in jaundiced patients (2-year survival 17%) vs. 26.1 months in non-jaundiced patients (2-year survival 39%, P < 0.001). In multivariate analysis, jaundice (HR1.89) was a poor prognostic factor for OS in surgically explored but not in resected patients. Six jaundiced patients did not develop a recurrence; none had liver- or common bile duct (CBD) invasion on imaging. Conclusion: Jaundice is associated with poor survival. However, jaundice is not an independent adverse prognostic factor in resected patients. Surgery should be considered in patients with limited disease and no CBD invasion on imaging

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

Extended Resections for Advanced Gallbladder Cancer: Results from a Nationwide Cohort Study

Background: Extended resections (i.e., major hepatectomy and/or pancreatoduodenectomy) are rarely performed for gallbladder cancer (GBC) because outcomes remain inconclusive. Data regarding extended resections from Western centers are sparse. This Dutch, multicenter cohort study analyzed the outcomes of patients who underwent extended resections for locally advanced GBC. Methods: Patients with GBC who underwent extended resection with curative intent between January 2000 and September 2018 were identified from the Netherlands Cancer Registry. Extended resection was defined as a major hepatectomy (resection of ≥ 3 liver segments), a pancreatoduodenectomy, or both. Treatment and survival data were obtained. Postoperative morbidity, mortality, survival, and characteristics of short- and long-term survivors were assessed. Results: The study included 33 patients. For 16 of the patients, R0 resection margins were achieved. Major postoperative complications (Clavien Dindo ≥ 3A) occurred for 19 patients, and 4 patients experienced postoperative mortality within 90 days. Recurrence occurred for 24 patients. The median overall survival (OS) was 12.8 months (95% confidence interval, 6.5–19.0 months). A 2-year survival period was achieved for 10 patients (30%) and a 5-year survival period for 5 patients (15%). Common bile duct, liver, perineural and perivascular invasion and jaundice were associated with reduced survival. All three recurrence-free patients had R0 resection margins and no liver invasion. Conclusion: The median OS after extended resections for advanced GBC was 12.8 months in this cohort. Although postoperative morbidity and mortality were significant, long-term survival (≥ 2 years) was achieved in a subset of patients. Therefore, GBC requiring major surgery does not preclude long-term survival, and a subgroup of patients benefit from surgery

Heterozygous missense variants of LMX1A lead to nonsyndromic hearing impairment and vestibular dysfunction

Unraveling the causes and pathomechanisms of progressive disorders is essential for the development of therapeutic strategies. Here, we identified heterozygous pathogenic missense variants of LMX1A in two families of Dutch origin with progressive nonsyndromic hearing impairment (HI), using whole exome sequencing. One variant, c.721G > C (p.Val241Leu), occurred de novo and is predicted to affect the homeodomain of LMX1A, which is essential for DNA binding. The second variant, c.290G > C (p.Cys97Ser), predicted to affect a zinc-binding residue of the second LIM domain that is involved in protein–protein interactions. Bi-allelic deleterious variants of Lmx1a are associated with a complex phenotype in mice, including deafness and vestibular defects, due to arrest of inner ear development. Although Lmx1a mouse mutants demonstrate neurological, skeletal, pigmentation and reproductive system abnormalities, no syndromic features were present in the participating subjects of either family. LMX1A has previously been suggested as a candidate gene for intellectual disability, but our data do not support this, as affected subjects displayed normal cognition. Large variability was observed in the age of onset (a)symmetry, severity and progression rate of HI. About half of the affected individuals displayed vestibular dysfunction and experienced symptoms thereof. The late-onset progressive phenotype and the absence of cochleovestibular malformations on computed tomography scans indicate that heterozygous defects of LMX1A do not result in severe developmental abnormalities in humans. We propose that a single LMX1A wild-type copy is sufficient for normal development but insufficient for maintenance of cochleovestibular function. Alternatively, minor cochleovestibular developmental abnormalities could eventually lead to the progressive phenotype seen in the families

Genome-wide association analyses identify new Brugada syndrome risk loci and highlight a new mechanism of sodium channel regulation in disease susceptibility.

Brugada syndrome (BrS) is a cardiac arrhythmia disorder associated with sudden death in young adults. With the exception of SCN5A, encoding the cardiac sodium channel Na1.5, susceptibility genes remain largely unknown. Here we performed a genome-wide association meta-analysis comprising 2,820 unrelated cases with BrS and 10,001 controls, and identified 21 association signals at 12 loci (10 new). Single nucleotide polymorphism (SNP)-heritability estimates indicate a strong polygenic influence. Polygenic risk score analyses based on the 21 susceptibility variants demonstrate varying cumulative contribution of common risk alleles among different patient subgroups, as well as genetic associations with cardiac electrical traits and disorders in the general population. The predominance of cardiac transcription factor loci indicates that transcriptional regulation is a key feature of BrS pathogenesis. Furthermore, functional studies conducted on MAPRE2, encoding the microtubule plus-end binding protein EB2, point to microtubule-related trafficking effects on Na1.5 expression as a new underlying molecular mechanism. Taken together, these findings broaden our understanding of the genetic architecture of BrS and provide new insights into its molecular underpinnings

Referral rate of patients with incidental gallbladder cancer and survival:outcomes of a multicentre retrospective study

Background: Treatment outcomes of incidental gallbladder cancer generally stem from tertiary referral centres, while many patients are initially diagnosed and managed in secondary care centres. Referral patterns of patients with incidental gallbladder cancer are poorly reported. This study aimed to evaluate incidental gallbladder cancer treatment in secondary centres, rates of referral to tertiary centres and its impact on survival. Methods: Medical records of patients with incidental gallbladder cancer diagnosed between 2000 and 2019 in 27 Dutch secondary centres were retrospectively reviewed. Patient characteristics, surgical treatment, tumour characteristics, referral pattern and survival were assessed. Predictors for overall survival were determined using multivariable Cox regression. Results: In total, 382 patients with incidental gallbladder cancer were included. Of 243 patients eligible for re-resection (pT1b–pT3, M0), 131 (53.9%) were referred to a tertiary centre. The reason not to refer, despite indication for re-resection, was not documented for 52 of 112 non-referred patients (46.4%). In total, 98 patients underwent additional surgery with curative intent (40.3%), 12 of these in the secondary centre. Median overall survival was 33 months (95% c.i. 24 to 42 months) in referred patients versus 17 months (95% c.i. 3 to 31 months) in the non-referred group (P = 0.019). Referral to a tertiary centre was independently associated with improved survival after correction for age, ASA classification, tumour stage and resection margin (HR 0.60, 95% c.i. 0.38 to 0.97; P = 0.037). Conclusion: Poor incidental gallbladder cancer referral rates were associated with worse survival. Age, performance status, resection margin or tumour stage should not preclude referral of a patient with incidental gallbladder cancer to a tertiary centre.</p

The diagnostic value of staging laparoscopy in gallbladder cancer: a nationwide cohort study

Background: Disseminated disease (DD) is often found at (re-)exploration in gallbladder cancer (GBC) patients. We aimed to assess the yield of staging laparoscopy (SL) and identify predictors for DD. Methods: This retrospective study included patients from all Dutch academic centres with primary GBC (pGBC) and incidentally diagnosed GBC (iGBC) planned for (re-)resection. The yield of SL was determined. In iGBC, predictive factors for DD were assessed. Results: In total, 290 patients were included. Of 183 included pGBC patients, 143 underwent laparotomy without SL, and 42 (29%) showed DD perioperatively. SL, conducted in 40 patients, identified DD in eight. DD was found in nine of 32 patients who underwent laparotomy after SL. Of 107 included iGBC patients, 100 underwent laparotomy without SL, and 19 showed DD perioperatively. SL, conducted in seven patients, identified DD in one. Cholecystitis (OR = 4.25; 95% CI 1.51–11.91) and primary R1/R2 resection (OR = 3.94; 95% CI 1.39–11.19) were independent predictive factors for DD. Conclusions: In pGBC patients, SL may identify DD in up to 20% of patients and should be part of standard management. In iGBC patients, SL is indicated after primary resection for cholecystitis and after initial R1/R2 resection due to the association of these factors with DD