OBJECTIVES: Endometrial Cancer Health Outcomes Study (ECHOS) is a real-world retrospective database study that evaluated treatment patterns and health outcomes in patients with endometrial cancer (EC). Progression-free survival (PFS) in patients with EC who received first-line (1L) platinum-based treatment (PBT) was described.

METHODS: ECHOS used data from electronic medical charts from a private hospital in Argentina (2010–2019) and claims data from private insurance plans in Brazil (2015-2020). Index (proxy for diagnosis) was the first date of an EC-related health term/ICD-10 code or procedure/treatment. PFS was evaluated for patients who received 1L PBT and carboplatin-paclitaxel (CP). Cumulative risk of progression using Kaplan-Meier was presented for the first five years of follow-up.

RESULTS: 805 patients with EC in Argentina and 3139 in Brazil were identified. In Argentina, 198 were treated with systemic therapy (24.6%). Of these, 73.7% (n=146) received PBT in 1L; 72.6% was CP (n=106). In Brazil, 755 (24.1%) patients received systemic therapy, 68.9% (n=520) received PBT, and almost 80% (n=411) received CP. In Argentina, over 60% (n=93) of patients using PBT in 1L progressed to another treatment or died (radiotherapy 12.9%, surgery 9.7%, antineoplastic drug 58.1%, death 19.4%). In Brazil, progression occurred in 41.3% (n=215) of PBT patients in the 1L group. Most progressed to another antineoplastic drug (80.5%); 19.5% died. In Argentina, 1–5-year cumulative risks of progression after 1L PBT were 46.3%, 61.8%, 68.6%, 75.8% and 75.8%, and in Brazil, 36.2%, 52.1%, 57.1%, 57.1% and 59.8%. A Sensitivity analysis evaluating CP patients in 1L showed similar results to PBT patients.

CONCLUSIONS: High progression rates were observed for EC patients receiving 1L PBT; risk estimates suggest most progressions occurred within 2 years with a high utilization of subsequent systemic therapy. Treatment approaches preventing/delaying progression beyond what is achievable with PBT are needed.