Smoking Habits in Lung Cancer Patients: A Hospital Based Case-Control Study in Izmir, Turkey

This retrospective, hospital based case-control study was designed to investigate the cigarette smoking history, the relationship betwe­en cigarette smoking and the risk of lung cancer in Izmir, Turkey. Six hundred cases with lung cancer (576 males, 24 females) and 600 controls were included in the study. The majority of lung can­cer patients (71%) were between 50-69 years old. Seventy three percent of the patients were current smokers, 23% were ex-smokers and 4% were non-smokers. Among the male patients, NSCLC was the most commonly diagnosed tumor type. The crude odds ratio (cOR) was 15.7 for current smokers, 7.4 for ex-smokers. The riskdecreased with increase in number of years since quitting and a hig­her age of starting to smoke. The cOR for current smokers was 21.0 in squamous cell carcinoma, 3.7 in adenocarcinoma, 37.5 in SCLC. Adenocarcinoma was the least related histological type to cigarette smoking. The number of cigarettes smoked per day, duration of smoking and the number of pack-years were found to be important risk factors for lung cancer.