Gallbladder cancer in Africa: A higher than expected rate in a "low-risk" population

Gallbladder cancer is the most common biliary tract malignancy. Reports from Africa suggest a low incidence of gallbladder cancer. Gallbladder cancer is most often diagnosed incidentally on pathology after cholecystectomy. The aim of this study was to determine the rate of incidental gallbladder cancer from cholecystectomy specimens in South Africa.

An audit of cholecystectomies for suspected gallstone disease in South Africa was done by reviewing specimens processed by the South Africa National Health Laboratory Service from 2003 and 2015. To assess risk factors for the presence of malignancy, a case control comparison was done. Logistic regression was used to determine the association between risk factors and malignancy. Between-group comparisons of sex were carried out using Fisher exact test. Ages were compared using the independent samples t test.

Pathological analysis was conducted on 33,467 cholecystectomy specimens. The rate of incidental gallbladder cancer rate was 0.39% with no difference between gender (P = .19). The mean age of the incidental gallbladder cancer patients (61.8 years; SD 13.4 y) was significantly higher than that of patients without gallbladder cancer (47.2 years; SD 15.0) (P < .0001). The majority of patients presented with T2 and T3 tumors. On multivariate analysis, only age, the presence of acute inflammation, and dysplasia were associated with the presence of incidental gallbladder cancer.

This large African study demonstrates a high rate of incidental gallbladder cancer in a patient population that has previously been deemed at low risk for gallbladder malignancies.