Necessity of Epigenetic Epidemiology Studies on the Carcinogenesis of Lung Cancer in Never Smokers.
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ABSTRACT:
SUBMITTER: Bae JM
PROVIDER: S-EPMC6182273 | biostudies-literature | 2018 Sep
REPOSITORIES: biostudies-literature
Publications
Necessity of Epigenetic Epidemiology Studies on the Carcinogenesis of Lung Cancer in Never Smokers.
Journal of preventive medicine and public health = Yebang Uihakhoe chi 20180708 5
Based on epidemiological and genomic characteristics, lung cancer in never smokers (LCNS) is a different disease from lung cancer in smokers. Based on current research, the main risk factor for LCNS may be air pollution. A recent case-control study in Koreans reported that nitrogen dioxide (NO2) may be a risk factor for LCNS. Additionally, a cohort study showed that exposure to NO2 was associated with significant hypomethylation. Thus, epigenetic epidemiology studies are needed in the near futur ...[more]
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Project description:IntroductionLung cancer in never smokers represents a distinct epidemiological, clinical, and molecular entity.ResultsMost 712 never smoking lung cancer patients were female (72%) with a median age at diagnosis of 62.2 years (18-94). Caucasians (46%), East Asians (42%), adenocarcinoma histology (87%) and presentation with metastatic disease at diagnosis (59%) were common. Of 515 patients with available archival tissue, the most common identified single mutations were EGFR (52.2%), followed by ALK (7.5%), KRAS (2.3%), TP53 (1.3%), ERBB2 (1%), BRAF (0.4%), PIK3CA (0.4%), SMAD4 (0.4%), CTNNB1 (0.2%), AKT1 (0.2%), and NRAS (0.2%); 8% tumors had multiple mutations, while 25.8% had none identified. Median overall survival (mOS) was 42.2 months (mo) for the entire cohort. Patients with mutations in their tumors had significantly better mOS (69.5 mo) when compared to those without (31.0 mo) (HR = 0.59; 95% CI: 0.44-0.79; p < 0.001). Earlier stage (p < 0.001), adenocarcinoma histology (p = 0.012), good performance status (p < 0.001) and use of targeted therapy (p < 0.001) were each independently associated with longer survival. Patients with ALK-translocation-positive tumours have significantly longer OS compared to those without any mutations (p = 0.0029) and to those with other and null mutations (p = 0.022).ConclusionsLung cancer in never smokers represents a distinct clinical and molecular entity characterized by a high incidence of targetable mutations and long survival.MethodsWe analyzed retrospectively the data from electronic patient records of never smokers diagnosed with lung cancer treated at the Princess Margaret Cancer Centre (Toronto) between 1988-2015 to characterize demographic and clinical features, pathology, molecular profile (using hotspot or targeted sequencing panels), treatment and survival.
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