Real‐world clinical outcomes of patients with high‐risk endometrial cancer or endometrial carcinosarcoma in England: A retrospective cohort study

Abstract Aim The objectives of this study were to describe patient characteristics and estimate real‐world disease‐free survival (rwDFS) and overall survival (OS) from initiation of first adjuvant therapy among patients with high‐risk endometrial cancer (EC) in England. Methods This was a retrospective cohort study based on data from Public Health England's National Cancer Registration and Analysis Service (NCRAS) between 2014 and 2023. Adult women with EC or endometrial carcinosarcoma at high risk of recurrence who received adjuvant therapy within 90 days after surgery were eligible for inclusion. We operationalized rwDFS as time to next treatment or death. Results In total, 6036 women (mean age: 67 years; 86% White) were eligible for inclusion, with a mean follow‐up of 48 months. During the study period, 45% of patients experienced recurrence and 39% of patients died due to any cause. Median rwDFS and OS from initiation of adjuvant therapy were estimated at 4.56 years (95% CI: 4.14–5.12) and 8.85 years (95% CI: 8.15–9.82), respectively. Estimated 2‐year and 5‐year probabilities were 0.64 (95% CI: 0.63–0.65) and 0.49 (95% CI: 0.48–0.50) for rwDFS, and 0.78 (95% CI: 0.77–0.79) and 0.60 (95% CI: 0.58–0.61) for OS, respectively. Disease recurrence was associated with a 3.23‐fold higher risk of death ( p  < 0.001). Kendall's τ correlation coefficient between rwDFS and OS was 0.75 (95% CI: 0.69–0.80, p  < 0.001). Conclusions The results from our study underscore the substantial clinical burden and unmet medical need of women with high‐risk EC and the validity of rwDFS as a surrogate for OS.