Postoperative radiotherapy for gallbladder cancer.

Abstract

289 Background: Gallbladder cancer (GBC) is a relatively uncommon malignancy with high recurrence rate and poor prognosis, even after curative resection. Although postoperative radiotherapy (RT) has been tried to improve the poor results of surgery alone, the benefit of postoperative RT for GBC is still a matter of debate. The present study aimed to evaluate the effect of postoperative RT on locoregional control (LRC), disease-free survival (DFS), and overall survival (OS) in patients with GBC. Methods: Between March 1998 and July 2009, 228 patients with GBC (T2-3 N0-2) underwent surgical resection with potentially curative aim (R0 or R1) at Asan Medical Center. Among the 228 patients, 86 received postoperative RT (RT group) with or without concurrent chemotherapy, and 142 did surgery alone (no-RT group). All patients with postoperative RT received three-dimensional conformal radiotherapy, and the median radiation dose was 50 Gy (range, 45-60 Gy) at 1.8 or 2.0 Gy/fraction daily. Among them, 57 patients (66.3%) had concurrent chemotherapy based on 5-fluorouracil. Results: The median follow-up time was 90 months (range, 35-96 months) for the surviving patients. Although RT group had significantly more advanced disease in overall stage (p = 0.005), T stage (p = 0.002), N stage (p = 0.010), and higher rate of R1 resection (p = 0.027), the 3-year LRC was 78% for RT group and 66% for no-RT group (p = 0.088). Also, there was no significant difference in the 3-year DFS and OS: 51% vs. 52% (p = 0.994) and 53% vs. 56% (p = 0.541), respectively. In multivariate analysis, postoperative RT was a significant predictive factor of improved LRC (p = 0.011), DFS (p = 0.016) and OS (p = 0.036). Conclusions: Although RT group had more adverse risk factors, the treatment outcomes of RT group were similar to those of no-RT group. Moreover, postoperative RT was a significant predictor of improved LRC, DFS and OS after adjusting these factors. These results suggest that postoperative RT might be effective in locoregional control and survival for patients with GBC.