Analysis and estimates of attributable risk factors for lung cancer in Nanjing, China

A case-control study was performed on 83 cases of primary pulmonary squamous cell carcinoma and 180 cases of primary pulmonary adenocarcinoma in Nanjing. Multivariate conditional logistic regression analysis showed five risk factors for pulmonary squamous carcinoma. These were: smoking, indoor air pollution due to cooking fumes, family tumor history, type of fuel used in the home, and use of coal stoves for heating in winter. The relative risks (RR) for these five risk factors were: 1.03 (95% CI, 1.00-1.06), 3.81 (95% CI, 1.06-13.73), 5.61 (95% CI, 1.23-15.79), 4.97 (95% CI, 0.8-30.88) and 3.72 (95% CI, 0.88-15.71), respectively. The respective population attributable risks (PAR) were: 68%, 52%, 28%, 55% and 36%. The four risk factors for pulmonary adenocarcinoma were smoking, cooking fumes, chronic bronchitis and family tumor history. The respective RRs were: 1.01 (95% CI, 1.00-1.03), 2.99 (95% CI, 1.68-5.34), 2.49 (95% CI, 1.68-5.34) and 4.77 (95% CI, 1.93-11.83). The respective PARs were: 20%, 47%, 18% and 18%. The combined PAR for the five risk factors for pulmonary squamous cell carcinoma was 94% and the combined PAR for the risk factors for pulmonary adenocarcinoma was 79%.