University hospital status and prognosis following surgery for esophageal cancer

Abstract

Background: We hypothesized that such prognosis is independently improved by surgery conducted within university hospitals.

Methods: Patients undergoing esophagectomy for esophageal cancer between 1987 and 2010 with follow-up until 2014 were identified from population-based nationwide Swedish cohort study. The association between university hospital status in and mortality was analyzed using a multivariable Cox-proportional hazards model, providing hazard ratios (HRs) with 95% confidence intervals (CIs). The HRs were adjusted for surgeon volume as well as age, comorbidity, tumor stage, histological subtype, neoadjuvant therapy and calendar period.

Results: Among 1820 included patients, 989 (54.3%) had surgery at one of the six university hospitals. Of the 83 and 569 patients operated on by the higher surgeon volume (17-46 cases) and middle surgeon volume groups (7-16 cases), 60 (72.3%) and 430 cases (75.6%) respectively were performed within university hospitals. University hospitals status indicated a non-significant reduction in all-cause 90-day mortality (HR = 0.82, 95% CI 0.61-1.10), but all-cause 5-year (HR = 0.94, 95% CI 0.83-1.05) and disease-specific 5-year mortality (HR = 1.00, 95% CI 0.88-1.14) were similar to non-university hospitals. Higher surgeon volume (17-46 cases), showed non-significant reductions in all-cause 90-day (HR = 0.49, 95% CI 0.21-1.14), all-cause 5-year (HR = 0.80, 95% CI 0.61-1.06) and disease-specific 5-year mortality (HR = 0.81, 95% CI 0.60-1.09).

Conclusions: This study found no improvements in long-term mortality from esophagectomy performed within university hospitals after adjustment for surgeon volume and other confounders.

Keywords: Esophageal cancer; Esophagectomy; Mortality; Survival; University.