Outcomes after the regionalization of care for high-grade endometrial cancers: a population-based study

Objective — In June 2013, Ontario Health – Cancer Care Ontario (CCO), the agency responsible for advancing cancer care in Ontario, Canada, published practice guidelines recommending that Gynaecologic Oncologists (GOs) at tertiary care centers manage the treatment of patients with high-grade endometrial cancers. This study examines the effects of this regionalization of care on patient outcomes.

Study Design — In this retrospective cohort study, patients diagnosed with non-endometrioid high-grade endometrial cancer from 2003-2017 were identified using province-wide administrative databases. Two periods were defined with January 1, 2014 as the cut-off, to allow 6 months for knowledge translation. Methods for segmented regression were used to test the effect of the guidelines. Multivariable Cox proportional hazards regression was used to evaluate whether regionalization of care had an impact on patient survival.

Results — There were 3518 patients with non-endometrioid high-grade endometrial cancer identified. The case mix as represented by patient comorbidities and the disease stage distribution did not differ significantly between the two regionalization periods. There was a significant increase (69% to 85%, p<0.001) in the proportion of primary surgeries performed by GOs after regionalization, which was not explained by secular trends. After regionalization, the proportion of patients who had surgical staging (50% to 63%, p<0.001), and the proportion of patients who received adjuvant treatment (65% to 71%, p<0.001) increased significantly. After adjusting for age, stage, and comorbidities, there was a decrease in the hazard of mortality (HR 0.85 (0.73-0.99), p=0.04) after regionalization.

Conclusions — The publication of a regionalization policy for the treatment of high-grade endometrial cancers in Ontario led to an increase in the proportion of surgeries performed by GOs. This also translated into a significant improvement in patient survival.