Background: The invasive front of tumor can provide prognostic information in many cancers. We investigated the prognostic morphological factors at the invasive front including tumor differentiation (Difinv ) and tumor budding (Bud) in biliary tract cancer (BTC).
Methods: The resected specimen from the 299 BTC patients were examined. Intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, gallbladder cancer, and ampulla of Vater cancer were found in 16%, 48%, 17%, and 19%, respectively. Difinv grade (G) 3 and Bud foci ≥5 were found in 47% and 10%. Tumor with Difinv G3 showed the high frequencies of Bud, vascular invasion (Ve) and nodal metastasis (LN) compared to tumor with Difinv G1/2 (Bud: 21% vs 0%, Ve: 71% vs 50%, LN: 52% vs 36%). Multivariate analysis revealed that the independent predictors were Difinv G3 (HR: 1.71), Bud foci ≥5 (HR: 2.14), Ve (HR: 1.56) and LN (HR: 2.59) in overall survival and were positive resection margin (HR: 1.71), Difinv G3 (HR: 1.75), Ve (HR: 1.50), and LN (HR: 2.19) in relapse free survival.
Conclusion: Poor differentiation at the invasive front of tumor was associated with poor prognosis and early relapse in BTC patients.
Keywords: biliary tract cancer; invasive front of tumor; prognostic factor; surgical pathology; tumor differentiation.
© 2018 Wiley Periodicals, Inc.