Lung Cancer in Non-smokers

Objective: To evaluate the characteristics of lung cancer in non-smokers.

Design: 3211 primary lung cancer cases diagnosed in our center between January 1992 and December 1995 were determined on the basis of pathology laboratory records. Clinical files of all the patients were analyzed retro­spectively.

Patients: The study included 368 non-smoker lung cancer patients. The control group was composed of 736 patients selected by systemic sampling method from 2560 smoker lung cancer patients.

Interventions: Non-smoker and smoker patients were deter­mined. Characteristics of the patients, tumor type, and possible risk factors for lung cancer were analyzed.

Results: Of 3211 cases, 368 (11.4%) were non-smoker and 

with a ratio of 1.03:1. The ratio of ade­nocarcinoma was 50.6% in non-smokers and 19-3% in smokers (p<0.0001). The ratio of squamous cell carcinoma and small cell carcinoma was higher in the smoker group. Forty-two per­cent of the non-smoker patients and 1.2% of the smoker patients were housewives (p<0.0001). The most frequently seen occupations among the smoker patients were farming and driving, 15.4% and 12% respectively. In the non-smoker group, mining (n=20), textile-related jobs (n=15), previous tuberculo­sis history (n=13), and asbestos exposure (n=12) were most fre­quently detected possible risk factors.

Conclusion: There are significant differences between smoker and non-smoker lung cancer patients with respect to tumour type, sex distribution and occupation.