Predictive factors of gastroduodenal bleeding after postoperative radiotherapy in biliary tract cancer.

Objective: To identify predictive factors for gastroduodenal bleeding after postoperative radiation therapy in patients with biliary tract cancer.

Methods: We identified 186 patients with biliary tract cancer who completed scheduled postoperative radiation therapy from March 2000 to August 2013. To isolate the effects of radiation on gastroduodenal bleeding, patients with pylorus-preserving pancreaticoduodenectomy, pylorus-resecting pancreaticoduodenectomy or Whipple surgery (n = 67) were excluded from this analysis. Postoperative radiation therapy was started at a median 5 weeks (range: 4-12 weeks) after surgery with a median dose of 44 Gy (range: 44-54), and chemotherapy was also concurrently administered to 102 patients.

Results: The median age of the patients was 59 years (range: 36-76 years). Of the 119 patients, 26 had intrahepatic cholangiocarcinoma, 29 had hilar cholangiocarcinoma, while 64 had extrahepatic tumors (gallbladder cancer, n = 53; proximal bile duct cancer, n = 10; choledochal cyst cancer, n = 1). Of all, 11 patients (9%) developed gastroduodenal bleeding. In univariate analyses, hepatic artery resection and gastroduodenal wall thickening on postoperative radiation therapy simulation computed tomography were statistically significant factors for gastroduodenal bleeding. Multivariate analysis by a logistic regression model using those two variables revealed that both parameters were independent predictors for gastroduodenal bleeding.

Conclusions: Concomitant hepatic artery resection and presence of gastroduodenal wall thickening on postoperative radiation therapy simulation computed tomography were predictive factors for gastroduodenal bleeding after postoperative radiation therapy in biliary tract cancer. In such cases, patients should be informed of the high risk of gastroduodenal bleeding, and should be closely observed during and after postoperative radiation therapy.