The prognostic value of two different radiotherapy techniques in esophageal cancer patients treated with neoadjuvant chemoradiotherapy

Background: Different radiotherapy techniques may reduce toxicity, but there is limited evidence confirming their impact on improving survival in patients undergoing neoadjuvant chemoradiotherapy (neo-CRT) for esophageal cancer. This study aims to explore the prognostic value of these techniques. Methods: Data from the Taiwan National Health Insurance Research Database (NHIRD) and the Taiwan Cancer Registry (TCR) were analyzed, encompassing 1,601 patients with clinical stage II or III esophageal cancer who underwent preoperative neo-CRT between 2008 and 2016. Prognostic factors for overall survival (OS) were determined using Kaplan-Meier plots and the Cox proportional hazards model. Propensity score matching (PSM) was applied to compare intensity-modulated radiotherapy (IMRT) (n=1,114) and rotational IMRT (rIMRT) (n=487) and identify prognostic factors for OS. Results: The adjusted hazard ratio (aHR) for postoperative OS between IMRT and rIMRT revealed no significant difference in 5-year OS [aHR =0.90; favoring rIMRT; 95% confidence interval (CI): 0.77–1.05], though a trend was observed (P=0.053). After PSM, the P value increased to 0.957, indicating no significant OS difference between IMRT and rIMRT. Male patients exhibited a worse prognosis than females (aHR =1.80; 95% CI: 1.25–2.59; P=0.002). The >70-year-old age group had poorer OS with an aHR of 1.69 (95% CI: 1.28–2.24; P=0.001) compared to the 40–49-year-old age group. Radiation doses exceeding 5,040 cGy were associated with poorer OS, with an aHR of 1.39 (95% CI: 1.14–1.70; P=0.001) relative to the 4,000–5,000 cGy dose range. High-volume hospitals were linked to higher OS compared to low-volume hospitals (aHR =1.35; 95% CI: 1.05–1.74; P=0.020). Finally, the aHR for clinical N (cN)0 relative to cN1 was 0.78 (95% CI: 0.62–0.99, P=0.044), indicating a better prognosis. Conclusions: Our NHIRD analysis revealed no significant OS difference in patients with stage II and III esophageal cancer receiving neo-CRT followed by surgery and treated with either IMRT or rIMRT. However, our findings identified several independent prognostic factors, including sex, age, cN category, radiation dose, and hospital volume, that influence OS.