The Mesentery in Robot-Assisted Total Mesorectal Excision

Impact of robotic total mesorectal excision upon pathology metrics in overweight males with low rectal cancer: a pooled analysis of 836 cases

The aim of this pooled analysis was to evaluate the impact of robotic total mesorectal excision (TME) on pathology metrics in Male Overweight patients with Low rectal cancer (MOL). This was a multicenter retrospective pooled analysis of data. Two groups were defined: MOL (Male, Overweight, Low rectal cancer) and non-MOL. Overweight was defined as BMI ≥ 25 kg/m2. Low rectal cancer was defined as cancer within 6 cm from the anal verge. The primary endpoints of this study were histopathological metrics, namely circumferential resection margin (CRM) (mm), CRM involvement rate (%), and the quality of TME. Circumferential resection margin (CRM) was involved if < 1 mm. 836 (106 MOL and 730 non-MOL) patients that underwent robotic TME by six surgeons over 3 years were compared. No significant differences in demographics and perioperative variables were found, except for operating time, distal margin, and number of lymph nodes harvested. CRM involvement rate did not significantly differ (7.5% vs. 5.5%, p = 0.395). Mean CRM was statistically significantly narrower in MOL patients (6.6 vs. 7.7 mm, p = 0.04). Quality of TME did not differ. Distance of tumor from the anal verge was the only independent predictor of CRM involvement. Robotic TME may provide optimal pathology metrics in overweight males with low rectal cancer. Although CRM was a few millimeters narrower in MOL, the values were within the range of uninvolved margins making the difference statistically significant, but not clinically. Being MOL was not a risk factor for involvement of circumferential resection margin.

Predictors for selective flexure mobilization during robotic anterior resection for rectal cancer: a prospective cohort analysis

INTRODUCTION

Splenic flexure mobilization (SFM) may be indicated during anterior resection to provide a tension-free anastomosis. However, to date, no score allows identifying patients who may benefit from SFM.

METHODS

Patients who underwent robotic anterior resection for rectal cancer were identified from a prospective register. Demographic and cancer-related variables were extracted, and predictors of SFM were identified using regression models. Thereafter, 20 patients with SFM and 20 patients without SFM were randomly selected and their pre-operative CTscan were reviewed. The radiological index was defined as 1/(sigmoid length/pelvis depth). The optimal cut-off value for predicting SFM was identified using ROC curve analysis.

RESULTS

Five hundred and twenty-four patients were included. SFM was performed in 121 patients (27.8%) and increased operative time by 21.8 min (95% CI: 11.3 to 32.4, p < 0.001). The incidence of postoperative complications did not differ between patient with or without SFM. Realization of an anastomosis was the main predictor for SFM (OR: 42.4, 95% CI: 5.8 to 308.5, p < 0.001). In patients with colorectal anastomosis, both sigmoid length (15 ± 5.1 cm versus 24.2 ± 80.9 cm, p < 0.001) and radiological index (1 ± 0.3 versus 0.6 ± 0.2, p < 0.001) differed between patients who had SFM and patients who did not. ROC curve analysis of the radiological index indicated an optimal cut-off value of 0.8 (sensitivity: 75%, specificity: 90%).

CONCLUSION

SFM was performed in 27.8% of patients who underwent robotic anterior resection, and increased operative time by 21.8 min. For optimal surgical planning, patients requiring SFM can be identified based on pre-operative CT using the index 1/(sigmoid length/pelvis depth) with a cut-off value set at 0.8.