Prognostic impact of postoperative radiation in patients with radical esophagectomy and pathologic lymph nodes positive esophageal cancer.

Abstract

101 Background: Though postoperative radiation for esophageal cancer is offered in selected cases, there is conflicting evidence as to whether it improves overall survival (OS). We performed a retrospective investigation to analyze the prognosis impact of adjuvant radiation in a large cohort of patients. Methods: From 2002 to 2008, 545 patients underwent radical esophagectomy (R0) with or without postoperative radiation were eligible for retrospectively analysis. Patients were grouped to surgery only (n=346) and surgery plus postoperative radiation therapy (PORT) (n=199). Radiation dose was 50 Gy in 25 fractions. Kaplan-Meier and Cox regression analysis were used to compare OS. Results: The use of PORT was associated with significantly improved OS ( p =0.006). The median OS was 31 months in the group receiving PORT and 21 months in the group undergoing surgery alone. The addition of PORT improved OS at 3 years from 38.3 to 45.8% compared with surgery alone. For American Joint Committee on Cancer (AJCC) stage III esophageal cancer (T1-2N2M0, T3N1-2M0, T4N1-3M0), there was significant improvement on OS ( p < 0.001) in PORT group, for not only metastatic lymph-node ratio <0.25 ( p = 0.047), but also metastatic lymph-node ratio >0.25 ( p = 0.013). However, for stages IIB disease (T1-2N1M0) there was no significant differences. Conclusions: This large population-based analysis supports the use of PORT for pathologic lymph nodes positive stage III esophageal cancer. Our results suggest that a subset of such patients may benefit from aggressive local therapy.