Prognostic factors in patients after definitive chemoradiation using involved‐field radiotherapy for esophageal cancer in a phase II study

BACKGROUND: A prospective study was performed on the use of chemoradiotherapy (CRT) for esophageal cancer (EC) with involved‐field radiation therapy (IFRT), based on 18‐fluorodeoxyglucose positron‐emission tomography. Prognostic factors for overall survival (OS) were analyzed. METHODS: Eligible patients included 63 adults with newly diagnosed, untreated, inoperable stage I–IV EC with lymph node metastases. Patients received 80 mg/m(2) nedaplatin per day on day 1, 800 mg/m(2) 5‐fluorouracil on days 1–4 intravenously repeated every 28 days for two to four cycles, and combined IFRT. Irradiation was applied only to the primary tumor and positive lymph nodes. RESULTS: Three‐year progression‐free survival and OS rates were 44.9% and 47.5%, respectively. The median survival time was 31.5 months. In univariate analyses for OS, Karnofsy Performance Scale <90% (P = 0.027), initial stage (P = 0.0087), T stage (P = 0.066), N stage (P = 0.000086), M stage of M1 (P = 0.0042), dysphagia score (P = 0.00017), tumor marker squamous cell carcinoma antigen >1.5 ng/mL (P = 0.0054), gross tumor volume (GTV) > 60 cc (P = 0.00011), and relative dose intensity (RDI) of chemotherapy ≤50% (P = 0.063) were found to be associated with significantly or marginally worse OS. In multivariate analyses for OS, GTV ≥ 60 cc (P = 0.00040), RDI < 50% (P = 0.00034), and cN2‐3 (P = 0.0020) were associated with significantly worse OS. CONCLUSION: GTV, RDI and N grading, were associated with OS after definitive CRT using IFRT for EC.