Comparison of three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and volumetric-modulated arc therapy in the treatment of cervical esophageal carcinoma

The aim of this study was to evaluate the effectiveness and toxicities of three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), and volumetric-modulated arc therapy (VMAT) in patients with cervical esophageal cancer. Specifically, we asked whether technological advances conferred an advantage with respect to the clinical curative effect. Seventy-eight patients with cervical esophageal cancer treated with definitive radiotherapy with or without concomitant chemotherapy at our institution between 2007 and 2014 were enrolled in the study: 26 received 3DCRT, 30 were treated with IMRT, and 22 underwent VMAT. Kaplan-Meier analysis and the Cox proportional hazard model were used to analyze overall survival (OS) and failure-free survival (FFS). Treatment-related toxicity was also assessed. For all patients, the 2-year OS and FFS rates were 56.2 and 53.9%, respectively. The 2-year OS for the 3DCRT, IMRT, and VMAT groups was 53.6, 55.6, and 60.6%, respectively (P = 0.965). The corresponding 2-year FFS rates were 49.5, 56.7, and 60.1% (P = 0.998). A univariate analysis of the complete response to treatment showed an advantage of treatment modality with respect to OS (P < 0.001). The development of acute hematologic toxicity was not significantly different among the three groups. The survival rates of patients treated with IMRT and VMAT were comparable to the survival of patients administered 3DCRT, while lower lung mean dose, V20, maximum dose of brachial plexus and spinal cord. Grade 1 radiation pneumonitis occurred significantly less in patients treated with IMRT and VMAT than with 3DCRT (P = 0.011). A complete response was the most important prognostic factor of the patients with cervical esophageal cancer.