Dosimetric predictor identification for radiation-induced liver disease after hypofractionated conformal radiotherapy for primary liver carcinoma patients with Child-Pugh Grade A cirrhosis

Purpose: Radiation-induced liver disease (RILD) is the most severe complication in liver cancer treatment. The aim of this study was to identify dosimetric predictors for RILD in primary liver carcinoma (PLC) patients with Child-Pugh Grade A cirrhosis after hypofractionated conformal radiotherapy (CRT). Methods and materials: A total of 114 eligible patients (mean age 45 years old) were enrolled and treated. The mean gross tumor volume (GTV) was (378.3 +/- 308.1) cm(3). A median dose of 53 Gy was delivered to the PLC by hypofractionated CRT (three fractions/week) with a median fraction size of 4.6 Gy (range: 4-6 Gy). Results: Patients were followed up for 1-79 months (median 19 months) after the completion of irradiation. RILD was diagnosed in nine (7.9%) patients. Univariate analyses revealed that GTV and the percentage of normal liver volume receiving more than 5-40 Gy irradiations (V(5-40)) were related to the risk of developing RILD. Multivariate analyses demonstrated that only GTV and V(20) were independent predictors. Using V(20) as the predictor for RILD, the accuracy, sensitivity, and specificity was 76.3%, 88.9%, and 75.2%, respectively. Conclusions: Our data suggest that V20 is the unique significant dosimetric predictor for RILD risks in PLC patients with Child-Pugh Grade A cirrhosis after hypofractionated CRT. (C) 2010 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 98 (2011) 265-269