The Impact of Obesity on the Perioperative, Clinicopathologic, and Oncologic Outcomes of Robot Assisted Total Mesorectal Excision for Rectal Cancer

Robotic-assisted versus laparoscopic surgery for colorectal cancer in high-risk patients: a systematic review and meta-analysis

BACKGROUND

Evidence of superiority of robotic-assisted surgery for colorectal resections remains limited. This systematic review and meta-analysis aims to compare robotic-assisted and laparoscopic surgical techniques in high-risk patients undergoing resections for colorectal cancer.

METHODS

Systematic searches were performed using Pubmed, Embase and Cochrane library databases from inception until December 2024. Randomised and non-randomised studies reporting outcomes of robotic-assisted or laparoscopic resections in the following high-risk categories were included: obesity, male gender, the elderly, low rectal cancer, neoadjuvant chemoradiotherapy and previous abdominal surgery. Comparative meta-analyses for all sufficiently reported outcomes were completed. Risk of bias was assessed using the ROBINS-I and RoB 2 tools for non-randomised and randomised studies, respectively.

RESULTS

48 studies, including a total of 34,846 patients were eligible for inclusion and 32 studies were utilised in the comparative meta-analyses. Conversion to open rates were significantly lower for robotic-assisted surgery in patients with obesity, male patients and patients with low rectal tumours (obese OR 0.41 [CI 0.32-0.51], p < 0.00001); male gender (OR 0.28 [CI 0.22-0.34], p < 0.00001); low tumours OR 0.10 [CI 0.02-0.58], p = 0.01). Length of stay was significantly reduced for robotic-assisted surgery in patients with obesity (SMD 0.25 [CI - 0.41 to - 0.09], p = 0.002). Operative time was significantly longer in all subgroups (obesity SMD 0.57 [CI 0.31-0.83], p < 0.0001; male gender SMD 0.77 [CI 0.17-1.37], p = 0.01; elderly SMD 0.50 [CI 0.18-0.83], p = 0.002; low rectal tumours SMD 0.48 [CI 0.12-0.84], p = 0.008; neoadjuvant chemoradiotherapy SMD 0.72 [CI 0.34-1.09], p = 0.0002; previous surgery SMD 1.55 [CI 0.05-3.06], p = 0.04). When calculable, blood loss, length of stay, complication rate and lymph node yield were comparable in all subgroups.

CONCLUSIONS

This review provides further evidence of non-inferiority of robotic-assisted surgery for colorectal cancer and demonstrates conversion rates are superior in specific, technically challenging operations.

Comparative analysis of robotic and laparoscopic surgery for mid and low rectal cancer in patients with varied body mass indexes: evaluating of short-term outcomes

The main aim of this study was to evaluate and contrast the efficacy of robotic and laparoscopic surgical procedures in the treatment of low and mid rectal cancer in different BMI (body mass index) groups. The clinical records of patients who had laparoscopic or robotic proctectomy at a single center between December 2019 and August 2023 were analyzed. Then we utilized a classification framework to categorize individuals based on their BMI into three unique groups: non-obese, overweight, and obese. The short-term efficacy was evaluated. A consecutive sample of 1413 patients was included in this retrospective investigation. 1158 people out of the total sample chose laparoscopic surgery, whereas 255 people chose robotic surgery. In the group of obese people, robotic surgery showed a statistically significant decrease in blood loss compared to laparoscopic surgery (P = 0.026). People who were overweight or obese were in the hospital for a shorter amount of time after robotic surgery than after laparoscopic surgery (P = 0.033 and P = 0.031, respectively). People with different BMIs in the robotic surgery group took less time to have a flatus passage and oral intake those in the laparoscopic surgery group. Oncological outcomes and the frequency of complications were comparable between the two treatments with different BMIs. Surgical resection of patients undergoing low-anterior surgery may benefit from a robotic approach, particularly in overweight and obese patients.

Impact of obesity on patients undergoing surgery for rectal cancer in Australia and New Zealand

PURPOSE

Patients with obesity undergoing rectal cancer surgery may have an increased risk of developing complications, though evidence is inconclusive. The aim of this study was to determine the direct impact of obesity on postoperative outcomes using data from a large clinical registry.

METHOD

The Binational Colorectal Cancer Audit registry was used to identify patients who underwent rectal cancer surgery in Australia and New Zealand from 2007-2021. Primary outcomes were inpatient surgical and medical complications. Logistic regression models were developed to describe the association between body-mass index (BMI) and outcomes.

RESULTS

Among 3,708 patients (median age 66 years [IQR 56.75-75], 65.0% male), 2.0% had a BMI < 18.5 kg/m2, 35.4% had a BMI of 18.5-24.9 kg/m2, 37.6% had a BMI of 25.0-29.9 kg/m2, 16.7% had a BMI of 30.0-34.9 kg/m2, and 8.2% had a BMI ≥ 35.0 kg/m2. Surgical complications occurred in 27.7% of patients with a BMI of 18.5-24.9 kg/m2, 26.6% of patients with a BMI of 25.0-29.9 kg/m2 (OR 0.91, 95% CI 0.76-1.10), 28.5% with a BMI of 30.0-34.9 kg/m2 (OR 0.96, 95% CI 0.76-1.21), and 33.2% with a BMI ≥ 35.0 kg/m2 (OR 1.27, 95% CI 0.94-1.71). Modelling BMI as a continuous variable confirmed a J-shaped relationship. The association between BMI and medical complications was more linear.

CONCLUSION

Risk of postoperative complications is increased in patients with obesity undergoing rectal cancer surgery.

A systematic review and meta-analysis of robotic-assisted transabdominal total mesorectal excision and transanal total mesorectal excision: which approach offers optimal short-term outcomes for mid-to-low rectal adenocarcinoma?

BACKGROUND

Resection of low rectal adenocarcinoma can be challenging in the narrow pelvis of male patients. Transanal total mesorectal excision (TaTME) appears to offer technical advantages for distal rectal tumours, and robotic-assisted transabdominal TME (rTME) was introduced in effort to improve operative precision and ergonomics. However, no study has comprehensively compared these approaches. The aim of the present study was to perform a systematic review of the literature to compare postoperative short-term outcomes in rTME and TaTME.

METHODS

A systematic online search (1974-July 2020) of MEDLINE, Embase, web of science and google scholar was conducted for trials, prospective or retrospective studies involving rTME, or TaTME for rectal cancer. Outcome variables included: hospital stay; operation duration, blood loss; resection margins; proportion of histologically complete resected specimens; lymph nodes; overall complications; anastomotic leak, and 30-day mortality.

RESULTS

Sixty-two articles met the inclusion criteria, including 37 studies (3835 patients) assessing rTME resection, 23 studies (1326 patients) involving TaTME and 2 comparing both (165 patients). Operating time was longer in rTME (309.2 min, 95% CI 285.5-332.8) than in TaTME studies (256.2 min, 95% CI 231.5-280.9) (p = 0.002). rTME resected specimens had a larger distal resection margin (2.62 cm, 95% CI 2.35-2.88) than in TaTME studies (2.10 cm, 95% CI 1.83-2.36) (p = 0.007). Other outcome variables did not significantly differ between the two techniques.

CONCLUSIONS

rTME provides similar pathological and short-term outcomes to TaTME and both are reasonable surgical approaches for patients with mid-to-low rectal cancer. To definitively answer the question of the optimal TME technique, we suggest a prospective trial comparing both techniques assessing long-term survival as a primary outcome.

Open Resection Compared to Mini-Invasive in Colorectal Cancer and Liver Metastases: A Meta-Analysis

Background: We performed a meta-analysis to evaluate the outcomes of minimally invasive surgery and open surgery in the simultaneous resection of colorectal cancer and synchronous colorectal liver metastases. Methods: A systematic literature search up to April 2021 was done and 13 studies included 1,181 subjects with colorectal cancer and synchronous colorectal liver metastases at the start of the study; 425 of them were using minimally invasive surgery and 756 were open surgery. They were reporting relationships between the outcomes of minimally invasive surgery and open surgery in the simultaneous resection of colorectal cancer and synchronous colorectal liver metastases. We calculated the odds ratio (OR) or the mean difference (MD) with 95% CIs to assess the outcomes of minimally invasive surgery and open surgery in the simultaneous resection of colorectal cancer and synchronous colorectal liver metastases using the dichotomous or continuous method with a random or fixed-effect model. Results: Minimally invasive surgery in subjects with colorectal cancer and synchronous colorectal liver metastases was significantly related to longer operation time (MD, 35.61; 95% CI, 7.36-63.87, p = 0.01), less blood loss (MD, -151.62; 95% CI, -228.84 to -74.40, p < 0.001), less blood transfusion needs (OR, 0.61; 95% CI, 0.42-0.89, p = 0.01), shorter length of hospital stay (MD, -3.26; 95% CI, -3.67 to -2.86, p < 0.001), lower overall complications (OR, 0.59; 95% CI, 0.45-0.79, p < 0.001), higher overall survival (OR, 1.66; 95% CI, 1.21-2.29, p = 0.002), and higher disease-free survival (OR, 1.49; 95% CI, 1.13-1.97, p = 0.005) compared to open surgery. Conclusions: Minimally invasive surgery in subjects with colorectal cancer and synchronous colorectal liver metastases may have less blood loss, less blood transfusion needs, shorter length of hospital stay, lower overall complications, higher overall survival, and higher disease-free survival with longer operation time compared with the open surgery. Furthers studies are required to validate these findings.

Obese patients and robotic colorectal surgery: systematic review and meta-analysis

BACKGROUND

Obesity is a major health problem, demonstrated to double the risk of colorectal cancer. The benefits of robotic colorectal surgery in obese patients remain largely unknown. This meta-analysis evaluated the clinical and pathological outcomes of robotic colorectal surgery in obese and non-obese patients.

METHODS

MEDLINE, Embase, Global Health, Healthcare Management Information Consortium (HMIC) and Midwives Information and Resources Service (MIDIRS) databases were searched on 1 August 2018 with no language restriction. Meta-analysis was performed according to PRISMA guidelines. Obese patients (BMI 30 kg/m2 or above) undergoing robotic colorectal cancer resections were compared with non-obese patients. Included outcome measures were: operative outcomes (duration of surgery, conversion to laparotomy, blood loss), postoperative complications, hospital length of stay and pathological outcomes (number of retrieved lymph nodes, positive circumferential resection margins and length of distal margin in rectal surgery).

RESULTS

A total of 131 full-text articles were reviewed, of which 12 met the inclusion criteria and were included in the final analysis. There were 3166 non-obese and 1420 obese patients. A longer duration of surgery was documented in obese compared with non-obese patients (weighted mean difference -21·99 (95 per cent c.i. -31·52 to -12·46) min; P < 0·001). Obese patients had a higher rate of conversion to laparotomy than non-obese patients (odds ratio 1·99, 95 per cent c.i. 1·54 to 2·56; P < 0·001). Blood loss, postoperative complications, length of hospital stay and pathological outcomes were not significantly different in obese and non-obese patients.

CONCLUSION

Robotic surgery in obese patients results in a significantly longer duration of surgery and higher conversion rates than in non-obese patients. Further studies should focus on better stratification of the obese population with colorectal disease as candidates for robotic procedures.

Mini-invasive vs open resection of colorectal cancer and liver metastases: A meta-analysis

BACKGROUND

The safety and feasibility of the simultaneous resection of primary colorectal cancer (CRC) and synchronous colorectal liver metastases (SCRLM) have been demonstrated in some studies. Combined resection is expected to be the optimal strategy for patients with CRC and SCRLM. However, traditional laparotomy is traumatic, and the treatment outcome of minimally invasive surgery (MIS) is still obscure.

AIM

To compare the treatment outcomes of MIS and open surgery (OS) for the simultaneous resection of CRC and SCRLM.

METHODS

A systematic search through December 22, 2018 was conducted in electronic databases (PubMed, EMBASE, Web of Science, and Cochrane Library). All studies comparing the clinical outcomes of MIS and OS for patients with CRC and SCRLM were included by eligibility criteria. The meta-analysis was performed using Review Manager Software. The quality of the pooled study was assessed using the Newcastle-Ottawa scale. The publication bias was evaluated by a funnel plot and the Begg’s and Egger’s tests. Fixed- and random-effects models were applied according to heterogeneity.

RESULTS

Ten retrospective cohort studies involving 502 patients (216 patients in the MIS group and 286 patients in the OS group) were included in this study. MIS was associated with less intraoperative blood loss [weighted mean difference (WMD) = -130.09, 95% confidence interval (CI): -210.95 to -49.23, P = 0.002] and blood transfusion [odds ratio (OR) = 0.53, 95%CI: 0.29 to 0.95, P = 0.03], faster recovery of intestinal function (WMD = -0.88 d, 95%CI: -1.58 to -0.19, P = 0.01) and diet (WMD = -1.54 d, 95%CI: -2.30 to -0.78, P < 0.0001), shorter length of postoperative hospital stay (WMD = -4.06 d, 95%CI: -5.95 to -2.18, P < 0.0001), and lower rates of surgical complications (OR = 0.60, 95%CI: 0.37 to 0.99, P = 0.04). However, the operation time, rates and severity of overall complications, and rates of general complications showed no significant differences between the MIS and OS groups. Moreover, the overall survival and disease-free survival after MIS were equivalent to those after OS.

CONCLUSION

Considering the studies included in this meta-analysis, MIS is a safe and effective alternative technique for the simultaneous resection of CRC and SCRLM. Compared with OS, MIS has less intraoperative blood loss and blood transfusion and quicker postoperative recovery. Furthermore, the two groups show equivalent long-term outcomes.