eP357 - How Pre-existing Colostomy Affects Robotic Surgery for Rectal Cancer After Neoadjuvant Treatment

Purpose/Background: At our hospital, we usually create a diverting colostomy for obstructive rectal cancer and initiate treatment such as neoadjuvant chemotherapy (NAC) and neoadjuvant chemoradiation therapy (NACRT). With the advent of minimally invasive surgery, these patients may be treated via a robotic approach. Compared to conventional laparoscopic surgery, robot-assisted surgical systems have several features such as a three-dimensional vision, a greater range of the motion and precision of instruments and better ergonomics. On the other hand, the existing stoma may interfere with optimal trocar position, and thus, affect the quality of robotic surgery. Moreover, lack of direct access to the patient may also endanger the stoma during surgery. We examined shot-term outcomes of robotic surgery for rectal cancer in terms of preexisting colostomy.Methods/Interventions: In this retrospective study, we investigated rectal cancer patients who underwent robotic surgery using a robotic platform after neoadjuvant treatment at our hospital between January 2018 and October 2023. According to stoma creation before neoadjuvant treatment, patients were divided into S-group (patients with a stoma) and NS-group (those without a stoma). Patients with a previous stoma who udnerwent stoma closure during rectal surgery were excluded. Baseline characteristics such as age, sex, body mass index, type of neoadjuvant treatment, and perioperative factors including surgical procedure, lateral pelvic node dissection (LPND), total operative time, console time, intraoperative blood loss, and postoperative complications including stoma-related complications were compared between the groups.Results/Outcomes: The S- and NS-groups comprised 9 patients (6 men and 3 women) and 106 patients (67 men and 39 women), respectively. Overall, NAC was administered to 9 patients and NACRT to 101 patients. Five patients received both NAC and NACRT. Other preoperative variables were similar between the groups. There was no intergroup difference in surgical procedures including LPND. A stoma was created in 89 patients of the NS-group (55 temporary, 34 permanent), Conversion to open surgery was required in 4 patients of the NS-group. The S-group required a longer console time (median: 367 min vs NS-group 278 min, p=0.066), but no difference was found in total operative time (median: 536 min vs 444 min, p=0.42) and blood loss (median: 120 ml vs 103 ml, p=0.71). The frequency of overall Grade 2- complications (Clavien-Dindo classification) was also similar between the groups. Notably, one patient of the S-group developed the exacerbation of preexisting stoma prolapse that was repaired by a purse-string suture method on day 9.Conclusion/

Discussion: Although console time was longer In rectal patients with a stoma, robotic surgery could be performed with safe similarly to those without a stoma after neoadjuvant treatment. Surgeons must be aware about an increased risk of stoma prolapse due to a high pneumoperitoneum pressure during robotic surgery.