Care Delivery Patterns, Processes, and Outcomes for Primary Ovarian Cancer Surgery: A Population-Based Review Using a National Administrative Database

Abstract

Objectives: In this pan-Canadian study, we sought to elucidate the current state of surgical care for primary ovarian cancers and factors influencing selected short-term outcomes; these were in-hospital mortality (IHM), major complications (MCs), failure-to-rescue (FTR), and hospital length of stay (LOS).

Methods: We created a population cohort using inpatient admission records from the Canadian Institute of Health Information data set (2004-2012). Multilevel logistic regression and flexible parametric survival analyses, adjusted for hospital clustering effect, were conducted to determine the effect of patient-specific factors (i.e., age, comorbidities, and admission category); procedural complexity; and the surgical volume and specialty of each care provider on the outcomes of interest.

Results: A total of 16 089 women underwent surgeries for primary ovarian cancer across Canada. The crude rates of IHM, MC, and FTR were 0.89%, 5.7%, and 9.09%, respectively, with a median LOS of four days (interquartile range 3 to 6). The majority of surgical procedures were performed by surgeons and hospitals with annual surgical volumes of less than five such procedures. Hospitals with higher surgical volumes were associated with lower risk of IHM (OR 0.95, 95% CI 0.91 to 0.99) and FTR (OR 0.95, 95% CI 0.91 to 0.99) and a higher chance of earlier discharge (hazard ratio [HR] 1.03, 95% CI 1.00 to 1.06). Surgeons with higher surgical volumes were associated with lower odds of early discharge (HR 0.90, 95% CI 0.87 to 0.94) and a higher risk of MC (OR 1.12, 95% CI 1.02 to 1.23). Compared with gynaecologic oncologists, general surgeons had a significantly higher risk of IHM (OR 3.50, 95% CI 1.82 to 6.74) and MC (OR 2.13, 95% CI 1.36 to 3.33) and lower odds of early discharge (HR 0.43, 95% CI 0.40 to 0.47).

Conclusion: Despite limitations in the administrative data set, valuable information was available for this pan-Canadian analysis. Our findings support centralization of surgical procedures for women with ovarian cancer in tertiary care centres with higher surgical volumes that are staffed by in-house multidisciplinary care teams and specialist surgeons.

Keywords: Ovarian cancer; centralization; quality of care; surgeon specialty; surgery; volume.