Confining the analysis to LKB1/STK11 mutation carriers, the probability of developing cancer by age 65 is 47% (95% CI: 27–73%), SMR of all and gastrointestinal cancers of 13.2 (95% CI: 0.5–27.1, P<0.001) and 32.0 (95% CI: 0.5–81.8, P<0.001), respectively. The gene discussed is STK11; the disease is cancer.