Volume outcome relationship in post-esophagectomy leak: A systematic review and meta-analysis.

BACKGROUND: Anastomotic leak after esophagectomy carries important short and long-term sequelae. We conducted a systematic review and meta-analysis to determine its association with surgical volume. MATERIALS AND METHODS: A systematic literature review was performed to identify all studies reporting on anastomotic leak after esophagectomy. Studies with <100 cases were excluded. The primary outcome was post-esophagectomy anastomotic leak, while secondary outcomes were operative mortality overall and after anastomotic leak. Pooled event rates (PER) were calculated and association with annual esophagectomy volume by center was investigated. RESULTS: Of the 3,932 retrieved articles, 472 were included (n=177,566 patients). The PER of anastomotic leak was 8.91% [95%CI=8.32; 9.53%]. The PER of early mortality overall and after anastomotic leak was 2.49% [95%CI=2.27; 2.74] and 11.39% [95%CI=9.66; 13.39], respectively. Centers with <37 annual esophagectomies had a higher leak rate compared to those with ≥37 annual esophagectomies (9.58% vs. 8.34%; P=0.040). On meta-regression, surgical volume was inversely associated with the PER of esophageal leak and of early mortality. CONCLUSION: The frequency of anastomotic leaks after esophagectomy, perioperative and leak associated mortality are inversely associated with esophagectomy volume.