Feasibility and safety of minimally invasive multivisceral resection for T4b rectal cancer: A 9-year review

ARTICLE HIGHLIGHTS

Research background

About 5%-10% of patients are diagnosed with locally advanced rectal cancer (LARC) on presentation. Multivisceral resection (MVR) and/or pelvic exenteration (PE) remains the only potential curative surgical treatment for LARC invading into other structures (i.e. cT4b tumours). However, MVR and/or PE is a major surgery with significant post-operative morbidity. There is currently no randomized controlled trial assessing T4 rectal tumours requiring extended resections with MVR.

Research motivation

Minimally invasive surgery (MIS) for other intra-abdominal pathologies has been shown to improve post-operative outcomes. However, evidence on the use of MIS for MVR and PE is not well established. Evidence on the use of robotic MVR and/or PE is even more scarce and needs to be reported.

Research objectives

Our primary aim is to assess the feasibility and safety of minimally invasive MVR (miMVR) in terms of the margin status and post-operative complications, and compare the outcomes between robotic and laparoscopic MVR. Our secondary aims are to assess the long-term survival of patients who underwent miVR, as well as compare between miVR compared to open MVR (oMVR).

Research methods

This is a single-center retrospective review of a prospectively maintained database from 1^st January 2015 to 31^st March 2023. Inclusion criteria were patients diagnosed with cT4b rectal cancer and underwent MVR, or stage 4 disease with resectable systemic metastases. Comparison in outcomes were made between miMVR and oMVR. Categorical values were described as percentages and analysed by the chi-square test. Continuous variables were expressed as median (range) and analysed by Mann-Whitney U test. Cumulative overall survival and RFS were analysed using Kaplan-Meier estimates with life table analysis. Subgroup analysis was performed with the above statistical methods to compare between robotic and laparoscopic MVR.

Research results

Forty-six patients were included in this study [oMVR: 12 (26.1%), miMVR: 34 (73.9%)]. Patients’ American Society of Anesthesiologists score, body mass index and co-morbidities were comparable between oMVR and miMVR. The incidence of neoadjuvant radiotherapy was lower in the oMVR group with near statistical significance (58.3% vs 85.3%, P = 0.052). There was a trend towards an increase in robotic MVR, with decrease in oMVR over the years. miMVR is associated with lower estimated blood loss (median 450 vs 1200 mL, P = 0.008), major morbidity (14.7% vs 50.0%, P = 0.014), post-operative intra-abdominal collections (11.8% vs 50.0%, P = 0.006), post-operative ileus (32.4% vs 66.7%, P = 0.04) and surgical site infection (11.8% vs 50.0%, P = 0.006) compared with oMVR. Length of stay was also shorter for miMVR compared with oMVR (median 10 vs 30 d, P = 0.001). More patients who had complex surgeries underwent robotic compared to laparoscopic MVR (robotic 57.1% vs laparoscopic 7.7%, P = 0.004). Incidence of R0 resection, overall complication, major morbidity, 30-d readmission were similar between laparoscopic and robotic MVR.

Research conclusions

miMVR is safe and feasible even in a low-volume institution for cT4b rectal cancer with acceptable R0 resection, short-term morbidity, 30-d mortality and long-term survival.

Research perspectives

Robotic MVR should be considered even in low volume institutions in view of the advantages conferred by robotic surgery in the presence of a proctor.