7: NEOADJUVANT CHEMORADIOTHERAPY OR CHEMOTHERAPY ALONE FOR OESOPHAGEAL CANCER: POPULATION-BASED COHORT STUDY

Abstract

Abstract Background and aim Although both neoadjuvant chemoradiotherapy (nCRT) and chemotherapy (nCT) are used as neoadjuvant treatment for oesophageal cancer, it is unknown if one provides a survival advantage over the other particularly with respect to histological subtype. This study aimed to compare prognosis following nCRT and nCT in patients undergoing oesophagectomy for oesophageal adenocarcinoma (OAC) and squamous cell carcinoma (OSCC). Methods Data from the National Cancer Database (2006 to 2015) were used to identify patients with OAC (n = 11,167; nCRT 9,972 (89%), nCT 1,195 (11%)) and OSCC (n = 2,367; nCRT 2 m155 (91%), nCT 212 (9%)). Propensity score matching and Cox multivariable analyses were used to account for treatment selection biases. Results In the matched cohort for OAC, nCRT provided higher rates of complete pathological response (35% vs. 21%, P < 0.001) and margin-negative resections (90% vs. 86%, P < 0.001). However, nCRT had similar survival to nCT (Hazard ratio (HR):1.04, 95% confidence interval (CI):0.95–1.14). The corresponding 5-year survival for nCRT and nCT were 36% and 37% (P = 0.1), respectively. For OSCC, nCRT had higher rates of complete pathological response (51% vs. 30%, P < 0.001) and margin-negative resections (93% vs. 82%, P < 0.001). nCRT had a statistically significant overall survival benefit (HR: 0.78, 95% CI: 0.62–0.97). The 5-year survival for nCRT and nCT were 45% versus 38% (P = 0.026), respectively. Conclusion Despite pathological benefits including primary tumour response from nCRT, there was no prognostic benefit to nCRT compared to nCT for OAC suggesting both modalities are equally acceptable. However, for OSCC, nCRT followed by surgery appears to remain the optimal treatment approach.