Long-term results of definitive chemoradiotherapy for unresectable locally advanced esophageal squamous cell carcinoma

Purpose: The present study aimed to evaluate the long-term results of definitive chemoradiotherapy (CRT) for unresectable locally advanced esophageal squamous cell carcinoma (LA-ESCC). Materials and methods: We analyzed eighty patients with unresectable LA-ESCC, who underwent definitive CRT between 2001 and 2014. The 5-year overall survival (OS), cause-specific survival (CSS), and progression-free survival (PFS) rates were calculated, and we investigated the prognostic factors and adverse events. Results: The median age was 66 years (range, 41-83 years). Histologically, all patients had squamous cell carcinoma. The most common tumor site was the middle thoracic esophagus in 43 (54%) patients. According to the eighth edition of the Union for International Cancer Control TNM classification, sixty-six patients (83%) had T4 disease, 59 (74%) had regional lymph node (LN) metastases, and 35 (44%) had distant LN metastases beyond the regional LN(M1LYM) disease. Forty-five (56%) and 35 (44%) patients belong to clinical stages IVA and IVB, respectively. The median follow-up period for survivors was 86 months. The 5-year OS, CSS, and PFS rateswere 20.2%, 25.7%, and 18.4%, respectively. On univariate analysis, only the performance status score was significantly associated with better overall survival (p = 0.026). Grade 3 or higher late adverse events were observed in 12 (15%) patients, and these included cardiopulmonary adverse events in 6 (8%) patients. Treatment-related death occurred in 3 (4%) patients. Conclusion: We showed the long-termresults of definitive CRT for unresectable LA-ESCC. The survivals are still poor and new treatment strategies need to be developed.