Outcome of neoadjuvant therapies for cancer of the oesophagus or gastro-oesophageal junction based on a national data registry

Background: Randomized trials have shown that neoadjuvant treatment improves survival in the curative treatment of oesophageal and gastro-oesophageal junction cancer. Results from population-based observational studies are, however, sparse and ambiguous. Methods: This prospective population-based cohort study included all patients who had oesophagectomy for cancer in Sweden, excluding clinical T1 N0, recorded in the National Register for Oesophageal and Gastric Cancer, 2006–2014. Patients were stratified into three groups: surgery alone, neoadjuvant chemotherapy and neoadjuvant chemoradiotherapy. Results: Neoadjuvant treatment was given to 521 patients (51·1 per cent) and 499 (48·9 per cent) received surgery alone. Neoadjuvant chemotherapy increased the risk of postoperative surgical complications compared with surgery alone (adjusted odds ratio 2·01, 95 per cent c.i. 1·24 to 3·25; P = 0·005). Postoperative mortality was significantly increased after neoadjuvant chemoradiotherapy compared with surgery alone (odds ratio 2·37, 1·06 to 5·29; P = 0·035). Survival improved in patients with squamous cell carcinoma after neoadjuvant chemotherapy, whereas after neoadjuvant chemoradiotherapy survival was significantly improved only in the subgroup with the highest performance status and without known co-morbidity. In adenocarcinoma there was a trend towards improved overall survival after neoadjuvant chemotherapy, but neoadjuvant chemoradiotherapy did not offer a survival benefit. Stratified analysis including only patients with adenocarcinoma in the highest performance category without known co-morbidity showed a strong trend towards improved survival after neoadjuvant chemotherapy compared with surgery alone (adjusted hazard ratio 0·47, 0·21 to 1·04; P = 0·061). Conclusion: For patients with squamous cell carcinoma of the oesophagus or gastro-oesophageal junction, neoadjuvant treatments seemed to increase long-term survival, but also the risk of postoperative morbidity and mortality, compared with surgery alone. Neither neoadjuvant treatment option seemed to improve survival significantly among patients with adenocarcinoma, compared with surgery alone.