Prospective risk of cancer and the influence of tobacco use in carriers of the p16-Leiden germline variant.

The p16-Leiden germline variant in the CDKN2A gene is associated with a high risk of melanoma and pancreatic cancer. The aims of this study were to assess the risk of developing other cancers and to determine whether tobacco use would alter cancer risk in carriers of such a variant. We therefore prospectively evaluated individuals with a p16-Leiden germline variant, participating in a pancreatic surveillance programme, for the occurrence of cancer (n=150). Tobacco use was assessed at the start of the surveillance programme. We found a significantly increased risk for melanoma (relative risk (RR) 41.3; 95% confidence interval (CI) 22.9-74.6) and pancreatic cancer (RR 80.8; 95% CI 44.7-146). In addition, increased risks were found for cancers of the lip, mouth and pharynx (RR 18.8; 95% CI 6.05-58.2) and respiratory tumours (RR 4.56; 95% CI 1.71-12.1). Current smokers developed significantly more cancers of the lip, mouth and pharynx, respiratory system and pancreas compared with former and never-smokers. In conclusion, this study shows that carriers of a p16-Leiden variant have an increased risk of developing various types of cancer, and smoking significantly increases the risk of frequently occurring cancers. Smoking cessation should be an integral part of the management of p16-Leiden variant carriers.