Genetic Analysis of Lung Cancer and the Germline Impact on Somatic Mutation Burden

International audienceBackground Germline genetic variation contributes to lung cancer (LC) susceptibility. Previous genome-wide association studies (GWAS) have implicated susceptibility loci involved in smoking behaviors and DNA repair genes, but further work is required to identify susceptibility variants. Methods To identify LC susceptibility loci, a family history-based genome-wide association by proxy (GWAx) of LC (48 843 European proxy LC patients, 195 387 controls) was combined with a previous LC GWAS (29 266 patients, 56 450 controls) by meta-analysis. Colocalization was used to explore candidate genes and overlap with existing traits at discovered susceptibility loci. Polygenic risk scores (PRS) were tested within an independent validation cohort (1 666 LC patients vs 6 664 controls) using variants selected from the LC susceptibility loci and a novel selection approach using published GWAS summary statistics. Finally, the effects of the LC PRS on somatic mutational burden were explored in patients whose tumor resections have been profiled by exome (n = 685) and genome sequencing (n = 61). Statistical tests were 2-sided. Results The GWAx–GWAS meta-analysis identified 8 novel LC loci. Colocalization implicated DNA repair genes (CHEK1), metabolic genes (CYP1A1), and smoking propensity genes (CHRNA4 and CHRNB2). PRS analysis demonstrated that these variants, as well as subgenome-wide significant variants related to expression quantitative trait loci and/or smoking propensity, assisted in LC genetic risk prediction (odds ratio = 1.37, 95% confidence interval = 1.29 to 1.45; P < .001). Patients with higher genetic PRS loads of smoking-related variants tended to have higher mutation burdens in their lung tumors. Conclusions This study has expanded the number of LC susceptibility loci and provided insights into the molecular mechanisms by which these susceptibility variants contribute to LC development

Irreducible dislocation of the hip in cerebral palsy patients treated by Schanz proximal femoral valgus osteotomy

Palliative Schanz proximal femoral valgus osteotomy is considered a common option for treatment of irreducible hip dislocation in cerebral palsy. From 1992 to 2005, Schanz osteotomy was indicated on 55 occasions in 35 nonambulatory patients with the quadriplegic form of cerebral palsy aged 9–18. Postoperatively, the main emphasis focussed on clinical presentation, improvement of hip range of motion, and pain relief. X-rays were carried out at three, six, and 12 months postoperatively with subsequent average follow up 98 ± 4.5 months. In all patients, the range of hip abduction and flexion increased. In 54 (98.2%) cases painful symptoms significantly improved. One patient (1.8%) had a subsequent femoral head excision because of persistent hip pain. Transient hip pain persisted in four patients (7.3%). Schanz valgus osteotomy improves the hip range of motion, relieves pain, and facilitates care of the patient. Schanz femoral osteotomy is a less invasive method compared to proximal femoral excision and should preferably be used in older children with neurogenic hip dislocation in whom reconstructive surgery is not indicated

Risk of upper aerodigestive tract cancer and type of alcoholic beverage: a European multicenter case–control study

The general relationship between cancers of the upper aerodigestive tract (UADT) and alcohol drinking is established. Nevertheless, it is uncertain whether different types of alcoholic beverages (wine, beer and liquor) carry different UADT cancer risks. Our study included 2,001 UADT cancer cases and 2,125 controls from 14 centres in 10 European countries. All cases were histologically or cytologically confirmed squamous cell carcinomas. Controls were frequency matched by sex, age and centre. Logistic regression models were used to estimate odds ratios (OR) and 95 % confidence intervals (95 %CI) adjusted for age, sex, centre, education level, vegetable and fruit intake, tobacco smoking and alcohol drinking, where appropriate. Risk of beverage-specific alcohol consumption were calculated among ‘pure drinker’ who consumed one beverage type exclusively, among ‘predominant drinkers’ who consumed one beverage type to more than 66 % and among ‘mixed drinkers’ who consumed more than one beverage type to similar proportions. Compared to never drinkers and adjusted for cumulative alcohol consumption, the OR and 95 %CI for wine, beer and liquor drinking, respectively, were 1.24 (0.86, 1.78), 1.54 (1.05, 2.27) and 0.94 (0.53, 1.64) among ‘pure drinkers’ (p value for heterogeneity across beverage types = 0.306), 1.05 (0.76,1.47), 1.25 (0.87,1.79) and 1.43 (0.95, 2.16) among ‘predominant drinkers’ (p value = 0.456), and 1.09 (0.79, 1.50), 1.20 (0.88, 1.63) and 1.12 (0.82, 1.53) among ‘mixed drinkers’ (p value = 0.889). Risk of UADT cancer increased with increasing consumption of all three alcohol beverage types. Our findings underscore the strong and comparable carcinogenic effect of ethanol in wine, beer and liquor on organs of the UADT