Analysis of patterns of failure and prognostic factors in resected extrahepatic bile duct cancer: Implications for postoperative adjuvant radiotherapy.

Abstract

266 Background: This study is aimed to analyze the patterns of failure and evaluate the prognostic factors in the patients with extrahepatic bile duct cancer (EBDC) for the potential role of postoperative adjuvant radiotherapy (PORT). Methods: We retrospectively reviewed the medical records of 106 patients with EBDC who received curative intent surgical resection. The definitions of tumor location were as follows: proximal EBDC (n = 29) from the confluent portion of the bilateral hepatic bile ducts to the junction of cystic duct, and distal EBDC (n = 77) from the junction of cystic duct to intrapancreatic portion. Nine patients underwent adjuvant chemoradiotherapy or chemotherapy. Results: The median follow-up time was 24 months for the surviving patients. Forty patients experienced locoregional failure (LRF) initially; 13 (45%) with proximal EBDC and 27 (35%) with distal EBDC. The hepatoduodenal ligament (HL) and tumor bed were the most common LRF sites. Distant metastasis (DM) occurred in 10 patients (34%) with proximal EBDC and 15 patients (19%) with distal EBDC. The liver was the most common organ of DM. In the multivariate analysis, perineural invasion (PNI) and postoperative high carbohydrate antigen (CA) 19-9 were associated with poor LRPFS. Conclusions: Both proximal and distal EBDC showed remarkable proportion of LRF. Because the HL and tumor bed are where routinely covered by PORT, it can be speculated that the addition of PORT can improve LRPFS in these patients. Especially PORT needs to be considered in patients with PNI and postoperative high CA 19-9 to improve locoregional control.