Abstract
Background and Objectives: Minimally invasive surgery is considered the standard of care for early-stage endometrial cancer. However, the oncological safety of intrauterine manipulator (IUM) use during laparoscopic hysterectomy remains controversial. The aim of this study was to evaluate the impact of intrauterine manipulator use during laparoscopic hysterectomy on oncological outcomes in patients with clinically early-stage endometrial cancer. Materials and Methods: In this retrospective cohort study, 612 patients with FIGO 2009 stage I-III endometrial cancer who underwent staging surgery at a tertiary center between January 2010 and May 2025 were included. Clinical and pathological characteristics were compared between laparoscopy (n = 168) and laparotomy (n = 444). To reduce selection bias, propensity score matching (PSM) was performed based on age, histological subtype, and FIGO stage. Kaplan-Meier survival analysis and Cox regression modeling were utilized to evaluate disease-free survival (DFS) and overall survival (OS). Results: After matching, groups were balanced except for higher rates of para-aortic lymphadenectomy and adjuvant therapy in the laparotomy group. IUM use was not associated with increased LVSI or positive peritoneal cytology. Recurrence was more frequent after laparoscopy (10.1% vs. 6.0%, p = 0.028), with inferior 5-year DFS (87.6% vs. 97.4%, HR 5.60, p = 0.0006), while OS was similar (82.0% vs. 87.6%, p = 0.842). In multivariate Cox analysis, independent predictors of worse DFS were non-endometrioid histology (HR 3.57), FIGO stage III (HR 3.06), grade 3 tumors (HR 2.63), and laparoscopic surgery (HR 0.51). For OS, non-endometrioid histology (HR 5.12), stage III disease (HR 2.98), and grade 3 tumors (HR 4.51) were independent adverse factors, whereas surgical approach was not. Conclusions: The use of an intrauterine manipulator in laparoscopic hysterectomy for early-stage endometrial cancer was linked to worse DFS but not OS. These findings suggest caution regarding the routine use of IUMs and highlight the need for prospective randomized trials to clarify their oncological safety.