De Novo Cancer Incidence after Cholecystectomy in Korean Population

Background: Cancer development after cholecystectomy remains debatable. We estimated the major cancer incidence rates after cholecystectomy stratified by age and sex. Methods: The records of 408,769 subjects aged >20 years were extracted from the National Health Insurance database from 2008 to 2016. The risks of major cancers were compared between the cholecystectomy and general populations using standardised incidence ratios (SIR). Results: The overall cancer incidence was comparable between cholecystectomy patients and the general population. However, patients aged <65 years who underwent cholecystectomy had a higher cancer risk than those aged >= 65 years and the general population (SIR 2.62; 95% confidence interval [CI] 2.15-3.08; SIR 1.36, 95% CI 1.32-1.40; and SIR 0.90, 95% CI 0.87-0.92 in men and SIR 1.91; 95% CI 1.71-2.10; SIR 1.07; 95% CI 1.03-1.10; and SIR 0.90; 95% CI 0.87-0.94 in women aged 20-34, 35-64, and >= 65 years at cholecystectomy). Colorectal and liver cancer incidences after cholecystectomy were higher than those in the general population regardless of age group and sex (SIR, 1.55 for colorectal cancer in men and women; SIR, 1.25 and 1.51 for liver cancer in men and women, respectively). However, for other major cancers, the risk was higher in patients who underwent cholecystectomy at a younger age than in those who underwent cholecystectomy at an age >= 65 years. Conclusion: Patients with cholecystectomy, especially those undergoing cholecystectomy at a younger age, need preventive strategies based on the cancer type.