Chemoradiotherapy and Increased Prescription Dose in Esophageal Squamous Cell Cancer: A Retrospective Study

To analyze the outcomes and adverse events of patients with esophageal squamous cell carcinoma (ESCC) treated with definitive chemoradiation with modified radiotherapy volume and increased radiation dose. This was a retrospective analysis of patients with ESCC treated with definitive chemoradiotherapy at the Sun Yat-sen University Cancer Center (02/2015 to 02/2017). The dose to the planning gross tumor volume (PGTV) and planning clinical tumor volume (PTV1) was 66-68 Gy (2.0-2.2 Gy/fraction). The dose to the planning regional lymph node drainage area volume (PTV2) was 46 Gy (2.0 Gy/fraction). Treatment response, adverse events, progression-free survival (PFS), overall survival (OS), and locoregional failure-free survival (LRFFS) were analyzed. Twenty-six patients were included. The median follow-up was 31 (range, 4.3-51.3) months. Sixteen (61.5%) patients had a complete response, and four (15.4%) achieved a partial response. The objective response rate was 76.9%, and the disease control rate was 80.8%. The median PFS and OS were not achieved. The 4-year PFS was 63.9%, and the 4-year OS was 71.0%. Grade 1-2 and 3-4 radiation-related esophagitis was observed in 15 (57.7%) and one (4.5%) patients, respectively. Grade 1-2 and 3-4 radiation-related pneumonitis was observed in 12 (46.2%) and one (4.5%) patients, respectively. No patients developed radiation-related heart or skin damage. The modified target volume definition and increased dose of definitive radiotherapy combined with chemotherapy in patients with ESCC had low toxicity and might improve survival, but additional trials are necessary to prove the superiority of this strategy.