Discussion on the treatment model and prognostic analysis of esophageal squamous cell carcinoma treated with induction chemotherapy combined with intensity-modulated radiation therapy

Objective To analyze the therapeutic effect and prognostic factors of induction chemotherapy plus intensity-modulated radiotherapy (IMRT) with or without consolidation chemotherapy for esophageal squamous cell carcinoma (ESCC). Methods One hundred and eight patients with ESCC treated between January 2010 to August 2014 were analyzed retrospectively. All patients received IMRT and platinum-based chemotherapy. The overall survival (OS) and local control (LC) rates were calculated using the Kaplan-Meier method and the univariate prognostic analyses were tested by the Log-rank test. The Cox proportional hazard model was used for multivariate prognostic analysis. Results The follow-up rate was 97.2%. The 1-, 3- and 5-year survival rates were 76.9%, 50.9% and 32.3% respectively, and the LC rates were 73.6%, 58.5% and 54.9% respectively. The median OS with and without consolidation chemotherapy were 51 and 15 months (χ2=5.076, P=0.024), respectively. Multivariate analysis showed that clinical N staging, recent curative effect and consolidation chemotherapy were important prognostic factors for OS, and recent curative effect was associated with LC. The rates of acute grade 3 radiation-induced esophagitis, gastrointestinal side effects, myelosuppression and radiation-induced pulmonary injury were 7.4%, 6.5%, 12% and 0.9%, respectively, and no grade 4 occurred. The late toxicity was mainly radiation-induced pulmonary fibrosis. Conclusions Induction chemotherapy plus IMRT with or without consolidation chemotherapy is safe and effective in the treatment of ESCC. The addition of consolidation chemotherapy may help prolong the survival of some patients and further research is necessary. Individualized treatment should be selected for patients who cannot tolerate or refuse concurrent chemoradiotherapy. Key words: Esophageal neoplasms; IMRT; Induction chemotherapy; Sequential; Prognosis