Many studies have been done regarding smokings relationship with cancer.In the United States tobacco use is involved in approximately one third of all cancer cases.There have been numerous studies on the causes of smoking as well as on methods of smoking cessation.Most of these have focused on people who do not have cancer and relatively little is known about the smoking cessation during and after cancer treatment.Among the possible causes for continuing to smoke with a diagnosis of cancer are depression, age, gender, and type of cancer.To evaluate the significance of depression as a factor in smoking cessation among patients with a diagnosis of cancer we conducted a double-blind placebo-controlled trial randomizing 246 cancer patients between 9 weeks of placebo versus daily bupropion, stratifying by pre-treatment depression symptoms.All patients received transdermal nicotine and behavioral counseling.The primary outcomes were biochemically confirmed abstinence at 7 days and 6 months after completion of treatment.Other factors evaluated were withdrawal symptoms, quality of life, compliance and side effects.A multi-variant analysis was performed to evaluate factors including gender, age and diagnosis.There was no main effect of bupropion versus placebo on abstinence (Odds Ratio =1.36, 95% CI: 0.38-4.81, p=0.64).Patients with depressive symptoms had significantly lower abstinence rates (OR =0.14, 95% CI: 0.02-0.8, p=0.3).However, bupropion increased the abstinence rates more for patients with depression symptoms.It also reduced withdrawal symptoms and improved the quality of life for patients with symptoms of depression.Patients who were older (p =<0.05) and had a diagnosis of a smoking related cancer (p =<0.05) were significantly more likely to stop smoking.Patients who had a smoking related cancer (p =<0.05) and female (p =<0.05) had a significantly greater likelihood of having depression symptoms.We concluded that adding bupropion to nicotine patches and behavioral counseling has a beneficial effect for patients with a diagnosis of cancer and depression symptoms.Patient age, gender and cancer-type may be important factors to consider in smoking cessation for patients with a diagnosis of cancer.