Impact of Prolonged Surgical Waiting Time on 5-Year Progression-Free Survival in Patients With Endometrial Cancer

To evaluate the impact of surgical waiting time (SWT) on 5-year progression-free survival (PFS). Secondary objectives were to evaluate 5-year overall survival (OS) and prognostic factors for recurrence and OS in endometrial cancer (EC), considering Thailand's Key Performance Indicator (KPI) recommending surgery within 4 weeks.

This retrospective cohort study included 377 patients with histologically confirmed EC who underwent primary surgery at Hatyai Hospital between October 2016 and September 2024. SWT was defined as the time from diagnostic biopsy to definitive surgery and categorized as early (≤ 4 weeks) or delayed (> 4 weeks). Survival outcomes were assessed using Kaplan-Meier curves and log-rank tests. Prognostic factors were analyzed using Cox proportional hazards models.

The median SWT was 32 days. Median follow-up was 23 months. Delayed surgery correlated with higher BMI, larger tumors, and increased recurrence (12.7% vs. 4.9%, p = 0.010). Advanced FIGO stage, non-endometrioid histology, grade 3 tumors, LVSI, and delayed SWT were significant recurrence risk factors. Multivariate analysis confirmed advanced stage (HR: 5.15, p < 0.001) and SWT > 4 weeks (HR: 3.22, p = 0.011) as independent predictors. Recurrence risk increased with longer delays (> 6 weeks: HR: 3.22; > 8 weeks: HR: 3.16). Kaplan-Meier curves showed significantly reduced PFS with prolonged SWT, while its effect on 5-year OS was not significant (p = 0.1).

Surgical delays beyond 4 weeks were associated with reduced PFS and increased recurrence, supporting Thailand's KPI and underscores the importance of timely surgery. The short follow-up may limit interpretation of long-term outcomes. Longer follow-up is warranted to confirm these results.