Researchers from Stockholm, Sweden, investigated the relationship between cholecystectomy and pancreatic cancer.
A total of 87,263 men and 181,049 women were included in the register-based retrospective cohort study. All had documented cholecystectomy for cholelithiasis between 1965 and 1997.
The cohort was followed up until the occurrence of any cancer, emigration, death, or the end of follow up (31 December 1997) - whichever came first.
During the period of observation, 1053 cases of pancreatic cancer were found. Of these, 231 (22%) occurred within 12 months after operation.
| Over 265,000 cholecystectomy patients were followed up.
After excluding cases and person years accrued during the first 2 years of follow up, the researchers observed a non-significant 6% excess risk for pancreatic cancer.
The relative risk did not increase with increasing follow up duration (standardized incidence ratio [SIR] equal to 0.98) 20 years or more after operation.
Patients with a comorbidity of diabetes or chronic pancreatitis had higher relative risks (SIR = 1.79 and SIR = 3.17, respectively).
After excluding patients with recorded diabetes or chronic pancreatitis, the relative risk was close to unity (SIR=1.01).
The authors of the study, from the Karolinska Institute and Hospital, concluded that their findings did not support the hypothesis that cholecystectomy increases the subsequent risk of pancreatic cancer.