The overall risk of gastrointestinal cancer was significantly higher in patients with cystic fibrosis than in the general population (pooled SIR 8·13, 95% CI 6·48-10·21; p<0·0001; log SIR 2·10, 95% CI 1·87-2·32; p<0·0001, I<sup>2</sup>=93·93%).
Subgroup analysis revealed that SIRT1 was significantly associated with worse OS in non-colorectal gastrointestinal cancer (sHR 1.82, 95% CI 1.50-2.21), in particular in gastric cancer (sHR 3.19, 95% CI 1.97-5.16) and hepatocellular carcinoma (sHR 1.53, 95% CI 1.16-2.01), with no evidence of heterogeneity or bias.