Abstract
Preoperative diagnosis of cholecystocolonic fistula (CCF) is difficult and the contribution of gallbladder cancer or colon cancer is unclear when there is associated malignancy. We present a case that was diagnosed with acute cholecystitis associated with CCF by multidetector computed tomography (MDCT) preoperatively and malignant neoplasm during emergency surgery. She was finally diagnosed with gallbladder cancer after the operation and underwent a two-stage surgery for regional lymph node dissection. Gallbladder cancer can be a primary malignant cancer causing CCF, whereas MDCT is useful for preoperative diagnosis of CCF. A treatment plan in consideration of gallbladder cancer is advisable for CCF associated with malignant tumor.