Robotic-assisted versus conventional laparoscopic surgery in the management of obese patients with early endometrial cancer in the sentinel lymph node era: a randomized controlled study (RObese)

Background Nearly 65% of patients with endometrial cancer who undergo primary hysterectomy have concurrent obesity. Retrospective data show advantages in using robotic surgery in these patients compared with conventional laparoscopy, namely lower conversion rate, increased rate of same-day discharge, and reduced blood loss. Nevertheless, to date no prospective randomized controlled trials have compared laparoscopic surgery versus robotic-assisted surgery in morbidly obese patients. Primary Objective The robotic-assisted versus conventional laparoscopic surgery in the management of obese patients with early endometrial cancer in the sentinel lymph node era: a randomized controlled study (RObese) trial aims to find the most appropriate minimally invasive surgical approach in morbidly obese patients with endometrial carcinoma. Study Hypothesis Robotic surgery will reduce conversions to laparotomy in endometrial cancer patients with obesity compared with those who undergo surgery with conventional laparoscopy. Trial Design This phase III multi-institutional study will randomize consecutive obese women with apparent early-stage endometrial cancer to either laparoscopic or robot-assisted surgery. Major Inclusion/Exclusion riteria The RObese trial will include obese (BMI≥30 kg/m 2 ) patients aged over 18 years with apparent 2009 Federation of Gynecology and Obstetrics (FIGO) stage IA-IB endometriod endometrial cancer. Primary Endpoint Conversion rate to laparotomy between laparoscopic surgery versus robot-assisted surgery. Sample Size RObese is a superiority trial. The clinical superiority margin for this study is defined as a difference in conversion rate of −6%. Assuming a significance level of 0.05 and a power of 80%, the study plans to randomize 566 patients. Estimated Dates for Completing Accrual and Presenting Results Patient recruitment will be completed by 2026, and follow-up will be completed by 2029 with presentation of data shortly thereafter. Two interim analyses are planned: one after the first 188 and the second after 376 randomized patients. Trial Registration NCT05974995