Effect of smoking on the survival of patients with lung cancer

A study was conducted to investigate the relationship between cigarette smoking and length of survival for patients with lung cancer. The present data consist of 460 male patients with lung cancer on whom information on smoking history was obtained prior to the diagnosis of the disease. Patients were grouped according to the number of cigarettes smoked daily, and survival rates were computed. No significant differences in the survival rates among patients in the various smoking categories were detected. Stage of disease was found to be the main factor in length of survival. The smokers of 2+ packs a day had the largest percentage of squamous cell carcinoma, the highest percentage of localized cases, and the best survival. The two latter findings may have occurred because squamous cell carcinoma has a lower metastatic potential than adenocarcinoma or because the presence of respiratory symptoms caused the heavy smokers to seek medical care earlier.