["Little is known about the relationship between a patient's personality and smoking behavior.", 'We assessed the smoking status of 262 male smokers who had been diagnosed with cancer and admitted to a teaching hospital, using a self-administered questionnaire that was mailed to the patients 6 months after discharge. The personality of the patients was assessed with the Kyushu University Egogram at admission, and the patients were categorized into five groups according to the ego state with the highest value among the five ego states, namely "Critical Parent" dominant, "Nurturing Parent" dominant, "Adult" dominant, "Free Child" dominant and "Adapted Child" dominant. Multivariate logistic regression analyses were used to assess the influence of the type of personality on smoking behavior after hospital discharge with adjustment for considerable predictive variables.', 'The smoking cessation rate at 6 months after hospital discharge was 63% (164/262). Multivariate analyses revealed that after adjustment for age, cancer site, length of hospital stay, time elapsed since last cigarette, self-confidence to quit smoking and strength of nicotine dependence, and being an Adult dominant personality were positively (p<0.01), and being a Free Child dominant personality was negatively (p<0.05) associated with post-discharge abstinence. These findings did not change when the non-responders (n=50) of the questionnaire were included in the analysis as post-discharge smokers.'] Is personality as assessed by egogram a possible independent predictive variable for post-discharge smoking abstinence in male cancer patients?