Background Obesity has been linked to increased mortality in several cancer types; however, the relationship between obesity and survival in metastatic melanoma is unknown. The aim of this study was to examine the association between BMI, progression-free survival (PFS), and overall survival (OS) in metastatic melanoma. Methods This study included 6 independent cohorts for a total of 1918 metastatic melanoma patients. These included two targeted therapy cohorts [randomized control trials (RCTs) of dabrafenib and trametinib (n=599) and vemurafenib and cobimetinib (n=240)], two immunotherapy cohorts [RCT of ipilimumab + dacarbazine (DTIC) (n=207) and a retrospective cohort treated with anti-PD-1/PDL-1 (n=331)], and two chemotherapy cohorts [RCT DTIC cohorts (n=320 and n=221)]. BMI was classified as normal (BMI 18 to <25; n=694 of 1918, 36.1%) overweight (BMI 25-29.9; n=711, 37.1%) or obese (BMI≥30; n=513, 26.7%). The primary outcomes were the association between BMI, PFS, and OS, stratified by treatment type and sex. These exploratory analyses were based on previously reported intention-to-treat data from the RCTs. The effect of BMI on PFS and OS was assessed by multivariable-adjusted Cox models in independent cohorts. In order to provide a more precise estimate of the association between BMI and outcomes, as well as the interaction between BMI, sex, and therapy type, adjusted hazard ratios were combined in mixed-effects meta-analyses and heterogeneity was explored with meta-regression analyses. Findings In the pooled analysis, obesity, as compared to normal BMI, was associated with improved survival in patients with metastatic melanoma [average adjusted hazard ratio (HR) and 95% CI: 0.77 (0.66-0.90) and 0.74 (0.58-0.95) for PFS and OS, respectively]. The survival benefit associated with obesity was restricted to patients treated with targeted therapy [0.72 (0.57-0.91) and 0.60 (0.45-0.79) for PFS and OS, respectively] and immunotherapy [0.75 (0.56-1.00) and 0.64 (0.47-0.86)]. No associations were observed with chemotherapy [0.87 (0.65-1.17) and 1.03 (0.80-1.34); treatment p for interaction = 0.61 and 0.01, for PFS and OS, respectively]. The prognostic effect of BMI with targeted and immune therapies differed by sex with pronounced inverse associations in males [PFS 0.67 (0.53-0.84) and OS 0.53 (0.40-0.70)], but not females [PFS 0.92 (0.70-1.23) and OS 0.85 (0.61-1.18), sex p for interaction= 0.08 and 0.03, for PFS and OS, respectively] Interpretation Obesity is associated with improved PFS and OS in metastatic melanoma, driven by strong associations observed in males treated with targeted or immune therapy. The magnitude of the benefit detected supports the need for investigation into the underlying mechanism of these unexpected observations Funding ASCO/CCF Young Investigator Award and ASCO/CCF Career Development Award to JLM

Importance The causal direction and magnitude of the association between telomere length and incidence of cancer and non-neoplastic diseases is uncertain owing to the susceptibility of observational studies to confounding and reverse causation. Objective To conduct a Mendelian randomization study, using germline genetic variants as instrumental variables, to appraise the causal relevance of telomere length for risk of cancer and non-neoplastic diseases. Data Sources Genomewide association studies (GWAS) published up to January 15, 2015. Study Selection GWAS of noncommunicable diseases that assayed germline genetic variation and did not select cohort or control participants on the basis of preexisting diseases. Of 163 GWAS of noncommunicable diseases identified, summary data from 103 were available. Data Extraction and Synthesis Summary association statistics for single nucleotide polymorphisms (SNPs) that are strongly associated with telomere length in the general population. Main Outcomes and Measures Odds ratios (ORs) and 95% confidence intervals (CIs) for disease per standard deviation (SD) higher telomere length due to germline genetic variation. Results Summary data were available for 35 cancers and 48 non-neoplastic diseases, corresponding to 420 081 cases (median cases, 2526 per disease) and 1 093 105 controls (median, 6789 per disease). Increased telomere length due to germline genetic variation was generally associated with increased risk for site-specific cancers. The strongest associations (ORs [95% CIs] per 1-SD change in genetically increased telomere length) were observed for glioma, 5.27 (3.15-8.81); serous low-malignant-potential ovarian cancer, 4.35 (2.39-7.94); lung adenocarcinoma, 3.19 (2.40-4.22); neuroblastoma, 2.98 (1.92-4.62); bladder cancer, 2.19 (1.32-3.66); melanoma, 1.87 (1.55-2.26); testicular cancer, 1.76 (1.02-3.04); kidney cancer, 1.55 (1.08-2.23); and endometrial cancer, 1.31 (1.07-1.61). Associations were stronger for rarer cancers and at tissue sites with lower rates of stem cell division. There was generally little evidence of association between genetically increased telomere length and risk of psychiatric, autoimmune, inflammatory, diabetic, and other non-neoplastic diseases, except for coronary heart disease (OR, 0.78 [95% CI, 0.67-0.90]), abdominal aortic aneurysm (OR, 0.63 [95% CI, 0.49-0.81]), celiac disease (OR, 0.42 [95% CI, 0.28-0.61]) and interstitial lung disease (OR, 0.09 [95% CI, 0.05-0.15]). Conclusions and Relevance It is likely that longer telomeres increase risk for several cancers but reduce risk for some non-neoplastic diseases, including cardiovascular diseases.

Thirteen common susceptibility loci have been reproducibly associated with cutaneous malignant melanoma (CMM). We report the results of an international two-stage meta-analysis of 11 genome-wide association studies (GWAS, five unpublished) of CMM and Stage two datasets, totaling 15,990 cases and 26,409 controls. Five loci not previously associated with CMM risk reached genome-wide significance (P < 5×10−8) as did two previously-reported but un-replicated loci and all thirteen established loci. Novel SNPs fall within putative melanocyte regulatory elements, and bioinformatic and eQTL data highlight candidate genes including one involved in telomere biology.

We performed a multistage genome-wide association study of melanoma. In a discovery cohort of 1804 melanoma cases and 1026 controls, we identified loci at chromosomes 15q13.1 (HERC2/OCA2 region) and 16q24.3 (MC1R) regions that reached genome-wide significance within this study and also found strong evidence for genetic effects on susceptibility to melanoma from markers on chromosome 9p21.3 in the p16/ARF region and on chromosome 1q21.3 (ARNT/LASS2/ANXA9 region). The most significant single-nucleotide polymorphisms (SNPs) in the 15q13.1 locus (rs1129038 and rs12913832) lie within a genomic region that has profound effects on eye and skin color; notably, 50% of variability in eye color is associated with variation in the SNP rs12913832. Because eye and skin colors vary across European populations, we further evaluated the associations of the significant SNPs after carefully adjusting for European substructure. We also evaluated the top 10 most significant SNPs by using data from three other genome-wide scans. Additional in silico data provided replication of the findings from the most significant region on chromosome 1q21.3 rs7412746 (P = 6 × 10(-10)). Together, these data identified several candidate genes for additional studies to identify causal variants predisposing to increased risk for developing melanoma.

Most genetic susceptibility to cutaneous melanoma remains to be discovered. Meta-analysis genome-wide association study (GWAS) of 36,760 melanoma cases (67% newly-genotyped) and 375,188 controls identified 54 significant loci with 68 independent SNPs. Analysis of risk estimates across geographical regions and host factors suggests the acral melanoma subtype is uniquely unrelated to pigmentation. Combining this meta-analysis with nevus count and hair color GWAS, and transcriptome association approaches, uncovered 31 potential secondary loci, for a total of 85 cutaneous melanoma susceptibility loci. These findings provide substantial insights into cutaneous melanoma genetic architecture, reinforcing the importance of nevogenesis, pigmentation, and telomere maintenance together with identifying potential new pathways for cutaneous melanoma pathogenesis.