Purpose: This study aimed to estimate the risk of cancer incidence and mortality according to adherence to lifestyle-related cancer prevention guidelines. Materials and Methods: Men and women who participated in the general health screening program in 2002 and 2003 provided by the National Health Insurance Service were included (n=8,325,492). Self-reported smoking, alcohol consumption, and physical activity habits and directly measured body mass index were collected. The participants were followed up until the date of cancer onset or death or 31 December 2018. The Cox proportional hazard model was used to evaluate the hazard ratio (HR) for cancer incidence and mortality according to different combinations of lifestyle behaviors. Results: Only 6% of men and 15% of women engaged in healthy behavior at baseline, such as not smoking, not drinking alcohol, being moderately or highly physically active, and within a normal body mass index range. Compared to the best combination of healthy lifestyle behaviors, the weak and moderate associations with increased all cancer incidence (HR < 1.7) and mortality (HR < 2.5) were observed in those with heavy alcohol consumption and in former or current smokers. HRs of cancer mortality were significantly increased among current smokers in most combinations. Conclusion Compared to full adherence to cancer prevention recommendations, unhealthy behaviors increase cancer risk. As few people meet these recommendations, there is a great opportunity for cancer prevention.

Purpose: Occupational exposure to pesticides is thought to be associated with lung cancer, but studies have yielded conflicting results. We performed a propensity score (PS) based analyses to evaluate the relationship between occupational exposure to pesticides and lung cancer risk in the Korea National Cancer Center community-based cohort study (KNCCCS). Materials and Methods: During the follow-up period, 123 incidental lung cancer cases were identified, of the 7,471 subjects in the final statistical analysis. Information about occupational exposure to pesticides and other factors was collected at enrollment (2003-2010). Cox proportional hazards regression analyses were conducted. Four PS-based approaches (i.e., matching, stratification, inverse probability-of-treatment weighting, and the use of the PS as a covariate) were adopted, and the results were compared. PS was obtained from the logistic regression model. Absolute standardized differences according to occupational exposure to pesticides were provided to evaluate the balance in baseline characteristics. Results: In the Cox proportional hazards regression model, the hazard ratio (HR) for lung cancer according to occupational exposure to pesticides was 1.82 (95% confidence interval [CI], 1.11 to 2.98). With all the propensity score matching (PSM) methods, the HRs for lung cancer based on exposure to pesticides ranged from 1.65 (95% CI, 1.04 to 2.64) (continuous term with PSM) to 2.84 (95% CI, 1.81 to 4.46) (stratification by 5 strata of the PS). The results varied slightly based on the method used, but the direction and statistical significance remained the same. Conclusion Our results strengthen the evidence for an association between occupational exposure to pesticides and the risk of lung cancer.