Patients undergoing surgery for oligometastatic oesophageal cancer survive for more than 2 years: bootstrapping systematic review data

Abstract

Oesophageal cancer oligometastasis is a state of limited systemic disease characterized by ˂5 metastases. Without surgery average survival is 4-12 months. We sought to estimate patient prognosis following the surgical resection of oligometastatic disease from oesophageal cancer. Eligible studies were identified through systematic search of PubMed and the Cochrane Library (end-of-search date: 20 November 2019). We estimated cumulative 1-, 3- and 5-year, as well as overall survival using bootstrap methodology with 1000000 repetitions per outcome. We investigated six studies involving 420 patients who underwent metastasectomy for oligometastasis from oesophageal cancer. Adenocarcinoma [77.3%; 95% confidence interval (CI) 62.8-87.3] was the most prevalent histological type followed by squamous cell carcinoma (22.7%; 95% CI 12.7-37.2). Metastatic lesions were typically synchronous (91.5%; 95% CI 87.5-94.1). Overall, 73.5% (95% CI 67.5-78.6) of the patients underwent resection of the primary and metastatic tumours synchronously. Neoadjuvant chemoradiotherapy was utilized in the majority of the patients (66.7%; 95% CI 49.5-80.3) followed by neoadjuvant chemotherapy (33.3%; 95% CI 19.6-50.5). The mean overall survival was 24.5 months (95% CI 14.4-34.6). One-year survival was 88.3% (95% CI 85.6-90.8). Three-year survival and 5-year survival were 36.3% (95% CI 15.3-7.3) and 23.8% (95% CI 12.0-35.7), respectively. Patients undergoing surgical resection of oesophageal oligometastasis survive for more than 24 months. Therefore, loco-regional control of oligometastatic disease appears to improve survival by at least 100%.