Cystic fibrosis F508del carriers and cancer risk: Results from the UK Biobank.

Cystic fibrosis (CF) carriers carrying one defective copy of a CFTR germline mutation are common in the general population. A recent study reported associations of CF carriers with risk for cancers of digestive organs and pancreatic cancer. In the current study, we assessed associations of CFTR F508del carriers with the risk for 54 types of cancers in the UK Biobank, a large population-based study. In Caucasians, compared to the carrier rate of 3.15% (12 357/392274) in noncancer subjects, the rate was significantly higher in cancer patients overall (2621/79619 = 3.29%), especially in patients with colorectal cancer (247/6667 = 3.70%), cancers of gallbladder and biliary tract (21/351 = 5.98%), thyroid cancer (30/665 = 4.51%) and unspecified non-Hodgkin's lymphoma (74/1805 = 4.10%), all P ≤ .05. In contrast, the carrier rate in patients with cancers of lung and bronchus was significantly lower (89/3463 = 2.57%), P = .05. The association of CFTR F508del carriers with these types of cancer remained significant after adjusting for respective cancer-specific risk factors. For pancreatic cancer, although a higher carrier rate (38/1004 = 3.78%) was found in patients with this cancer, the difference was not statistically significant (P = .26). This null association was unlikely due to lack of statistical power; the large sample size of our study had >80% power, at a significance level of .05, to detect an association of >1.5-fold increased risk. In conclusion, the identified associations of CFTR F508del carriers with multiple types of cancer may have potential biological and clinical implications if confirmed in independent study populations.