Effectiveness of esophagectomy in patients with thoracic esophageal squamous cell carcinoma receiving definitive radiotherapy or concurrent chemoradiotherapy through intensity-modulated radiation therapy techniques

BACKGROUND Few large, prospective, randomized studies have investigated the effectiveness of esophagectomy in patients with thoracic esophageal squamous cell carcinoma (TESCC) who receive definitive radiotherapy (RT) or concurrent chemoradiotherapy (CCRT) through modern, intensity modulated-RT (IMRT) techniques. The therapeutic effects of esophagectomy in patients with TESCC were evaluated using modern clinical staging and RT techniques and suitable RT doses. METHODS The authors analyzed data from patients with TESCC from the Taiwan Cancer Registry database. Patients were categorized into the following groups on the basis of treatment modality to compare their outcomes: group 1 received definitive CCRT, group 2 received neoadjuvant RT followed by esophagectomy (total IMRT dose, ≥50 grays [Gy]), and group 3 receiving neoadjuvant CCRT followed by esophagectomy (total IMRT dose, ≥ 50 Gy). The median total RT dose and fraction size were 50.4 Gy and 1.8 Gy per fraction, respectively. Group 1 was used as the control arm for investigating the risk of mortality after treatment. RESULTS In total, 3123 patients who had TESCC without distant metastasis were enrolled. Patient ages 65 years and older, Charlson comorbidity index scores ≥3, advanced clinical stages (IIA-IIIC), alcohol consumption, and cigarette smoking were identified as significant, independent poor prognostic risk factors for overall survival in multivariate Cox regression analyses. In group 3, after adjustment for confounders, the adjusted hazard ratios (95% confidence intervals [CIs]) for overall mortality were 0.62 (95% CI, 0.41-0.93) for patients with clinical stage IIA disease, 0.61 (95% CI, 0.41-0.91) for those with clinical stage IIB disease, 0.47 (95% CI, 0.38-0.55) for those with clinical stage IIIA disease, 0.47 (95% CI, 0.39-0.56) for those with clinical stage IIIB disease, and 0.46 (95% CI, 0.37-0.57) for those with clinical stage IIIC disease. CONCLUSIONS Esophagectomy can be beneficial in patients with TESCC after definitive CCRT, especially in those who have advanced-stage disease. Cancer 2017;123:2043–2053. © 2017 American Cancer Society.