834 Nationwide retrospective cohort study on oncological outcomes after laparotomic, laparoscopic and robot-assisted laparoscopic staging for early stage high-intermediate or high-risk endometrial cancer

Introduction/Background Aim To compare oncological outcomes in patients with early stage high-intermediate or high-risk endometrial cancer undergoing surgical staging by laparotomy, conventional laparoscopy or robot-assisted laparoscopy. Methodology Patients who underwent staging surgery for stage I-II (FIGO 2009), high-intermediate or high-risk endometrial cancer between 2015 and 2021 were identified in the Netherlands Cancer Registry. Five-year disease-free survival and overall survival were calculated using the Kaplan-Meier method, and differences between groups were evaluated using log-rank testing. Survival analyses were also stratified by histological subtype. The effect of surgical modality on the risk of recurrence and all-cause death was assessed by performing Cox regression analysis with inverse probability treatment weighting. Results In total 941 patients met the inclusion criteria of whom 399 (42.4%) underwent staging surgery by laparotomy, 273 (29.0%) by laparoscopy and 269 (28.6%) by robot-assisted laparoscopy. Baseline characteristics were generally comparable across the three groups. No difference in disease-free survival (75.0% vs 71.2% vs 79.0% p = 0.35) or overall survival (72.7% vs 72.3% vs 71.2% p=0.98) was observed between patients after laparotomy, laparoscopy or robot-assisted laparoscopy respectively. Sub-analyses based on histologic subtype also showed comparable disease-free survival and overall survival between surgical approaches. After correcting for possible confounders by means of inverse probability treatment weighting there was no significantly increased risk of recurrence or risk of death of all cause after laparoscopy or robot-assisted laparoscopy compared to laparotomy. Conclusion Laparoscopic and robot-assisted laparoscopic staging surgery in women with early stage high-intermediate or high-risk endometrial cancer seem a safe alternative to laparotomic staging surgery. Disclosures The authors declare that they have no relevant or material financial interests that relate to the research described in this abstract.