Outcomes of robotic esophagectomies for esophageal cancer by hospital volume: an analysis of the national cancer database.

Background: Robotic minimally invasive esophagectomies (RMIE) have been associated with superior outcomes; however, it is unclear if these are specific to robotic technique or are present only at high-volume institutions. We hypothesize that low-volume RMIE centers would have inferior outcomes.

Methods: The National Cancer Database (NCDB) identified patients receiving RMIE from 2010 to 2016. Based on the total number of RMIE performed by each hospital system, the lowest quartile performed ≤ 9 RMIE over the study period. Ninety-day mortality, number of lymph nodes evaluated, margins status, unplanned readmissions, length of stay (LOS), and overall survival were compared. Regression models were used to account for confounding.

Results: 1565 robotic esophagectomies were performed by 212 institutions. 173 hospitals performed ≤ 9 RMIE (totaling 478 operations over the study period, 30.5% of RMIE) and 39 hospitals performed > 9 RMIE (1087 operations, 69.5%). Hospitals performing > 9 RMIE were more likely to be academic centers (90.4% vs 66.2%, p < 0.001), have patients with advanced tumor stage (65.3% vs 59.8%, p = 0.049), andadministered preoperative radiation (72.8% vs 66.3%, p = 0.010). There were no differences based on demographics, nodal stage, or usage of preoperative chemotherapy. On multivariable regressions, hospitals performing ≤ 9 RMIE were associated with a greater likelihood of experiencing a 90-day mortality, a reduced number of lymph nodes evaluated, and a longer LOS; however, there was no association with rates of positive margins or unplanned readmissions. Median overall survival was decreased at institutions performing ≤ 9 RMIE (37.3 vs 51.5 months, p < 0.001). Multivariable Cox regression demonstrated an association with poor survival comparing hospitals performing ≤ 9 to > 9 RMIE (HR 1.327, p = 0.018).

Conclusion: Many robotic esophagectomies occur at institutions which performed relatively few RMIE and were associated with inferior short- and long-term outcomes. These data argue for regionalization of robotic esophagectomies or enhanced training in lower volume hospitals.