An intervention study of smoking cessation with feedback on genetic cancer susceptibility in Japan

Background. To evaluate whether feedback of genetic information regarding an L-myc polymorphism, identified as impacting on tobacco-related cancer risk, has an influence on smoking cessation, an intervention study was conducted. Methods. We recruited smokers from first-visit outpatients at Aichi Cancer Center Hospital. Six hundred and seventeen participated and were allocated into two groups: the biomarker feedback group (BF) and the follow-up smoking status group (FS). The subjects were asked for their smoking status at enrolment and at 3- and 9-month follow-ups. BF subjects were notified about their L-myc genotype. Results. The smoking cessation rate at 9-month follow-up was essentially the same for both BF and FS cases, at 18.8% and 17.0%, respectively (P = 0.798). However, a difference in the rate was evident with non-cancer subjects (12.7% and 8.4%, respectively, P = 0.237), especially in females (15.0% and 4.2%, respectively, P = 0.024). The non-cancer subjects informed of their genotype were more likely to quit smoking than the FS patients; particularly in those having a risky genotype, this was significant (odds ratio: 2.87, P = 0.003). Again it was most prominent in females. Conclusion. Feedback regarding an L-myc polymorphism did not impact on smoking cessation overall but appeared to benefit smokers without cancer. In addition, gender could affect the response to the feedback.