Robotic vs. laparoscopic intersphincteric resection for low rectal cancer: a case matched study reporting a median of 7-year long-term oncological and functional outcomes

A Porcine Model of Laparoscopic Intersphincteric Resection for Ultra-Low Rectal Cancer

OBJECTIVE

To develop a porcine model for laparoscopic intersphincteric resection (ISR) targeting ultra-low rectal cancer.

METHODS

Six Bama mini-pigs underwent a standard laparoscopic ISR procedure: (1) Ligation and transection of the inferior mesenteric vessels; (2) Exposure and sparing of the pelvic autonomic nerves; (3) Dissection of the rectum; (4) Dissection and transection of hiatal ligament and rectourethralis muscle; (5) Transanal dissection of the anal canal; (6) Dissection of the intersphincteric space (ISS); (7) End-to-end handsewn coloanal anastomosis (CAA). Pathological evaluations were conducted to ascertain the precision of the ISR. Furthermore, postoperative fecal incontinence scores were systematically assessed on a weekly basis throughout a 12-week post-surgery follow-up period.

RESULTS

All six pigs survived surgery without conversion to an open approach. There were no occurrences of incisional infection or any surgical complications, including anastomotic leakage, anastomotic bleeding, or ileus. Postoperatively, one pig manifested constipation and three exhibited anal redness, both conditions ameliorating within a week. No erosive ulcers were detected. Notably, all animals exhibited fecal staining on their tails within the first two weeks post-surgery, transitioning to formed feces by the third week. Improvement in defecation frequency was observed after 6 weeks, with a noticeable reduction in defecation areas after one month. Incontinence scores, evaluated three months post ISR surgery, revealed no significant abnormalities in anal function compared to preoperative assessments.

CONCLUSIONS

This study established a replicable porcine model for laparoscopic ISR, demonstrating its potential utility in clinical and fundamental research related to ultra-low rectal cancer treatment.

Effect of neoadjuvant therapy on textbook outcomes in minimally invasive rectal cancer surgery

AIM

Textbook outcome (TO), a combined quality indicator, encompasses key postoperative indicators such as the absence of complications, R0 resection, and no prolonged length of day. It has been suggested to be of additional value over single outcome parameters in short-term outcomes of surgical treatment. The main objective of this research was to assess the relationship between TO and neoadjuvant therapy (NT), thereby providing insights into NT's role in surgical quality.

METHOD

Patients who underwent minimally invasive rectal surgery were enrolled between January 2019 and June 2024. TO was defined as achieving R0 resection, at least 12 lymph nodes harvested, no adverse outcomes (Clavien-Dindo score ≥ 3, readmission, or mortality within 30 days), and length of stay within the ≤ 75th percentile for the treatment year. The relationship between TO and NT was analyzed using regression analyses. Subgroup analysis and hierarchical regression were conducted to investigate potential influencing factors and interactions.

RESULTS

405 patients were enrolled, with 204 achieving TO. NT was associated with a reduction in TO (OR: 0.37, 95% CI: 0.21 ~ 0.65, p < 0.001), while robotic surgery (OR: 2.88, 95% CI: 1.62 ~ 5.11), total laparoscopic surgery (OR: 2.79, 95% CI: 1.71 ~ 4.56), enhanced recovery after surgery (OR: 1.62, 95% CI: 1.02 ~ 2.59), and stoma (OR: 1.87, 95% CI: 1.18 ~ 2.96) were associated with an increased rate of TO. The impact of NT on TO varied depending on surgery duration; prolonged surgical time exacerbated the negative effect of NT on TO. This observation was consistent with a significant interaction effect.

CONCLUSION

NT is associated with a lower TO rate, especially in patients with prolonged surgical time. Robotic surgery, total laparoscopic surgery, enhanced recovery after surgery, and stoma can improve achieve TO.

Surgical protocol of robotic liver resection using a two-surgeon technique (TAKUMI-3): a technical note and initial outcomes

BACKGROUND

Internationally, evidence supporting robotic liver resection (RLR) has gradually increased in recent years. However, a standardized protocol for RLR remains lacking. This study describes a surgical protocol and the initial outcomes of RLR in a high-volume center for robotic hepatopancreatobiliary surgery in Japan.

METHODS

Patients were placed in the reverse Trendelenburg position, with a supine position for anterolateral tumors and left lateral position for posterosuperior tumors. Our standard RLR protocol involved a two-surgeon technique. Liver parenchymal transection was performed by an assistant using the clamp crush technique with a console, with or without a laparoscopic Cavitron ultrasonic surgical aspirator (CUSA). Surgical techniques, including the tips, tricks, and pitfalls of RLR, are also demonstrated.

RESULTS

We performed 113 RLR at our institution for common primary diseases, including hepatocellular carcinoma (n = 52, 46.0%) and metastatic tumors (n = 48, 42.5%) between July 2022 and December 2024. The median operative time and estimated blood loss were 156 min (interquartile range [IQR], 121-209 min) and 20 mL (IQR, 0-100 mL), respectively. During liver parenchymal transection, a laparoscopic CUSA was used in 59 patients (52.2%), and a water-jet scalpel was used in 12 patients (10.6%). The incidence of mortality, major complications, and bile leakage was 0%, 6.2%, and 2.7%, respectively. The median hospital stay was 7 days (IQR, 6-9 days).

CONCLUSIONS

We successfully introduced an RLR program using the two-surgeon technique. Safe implementation of RLR can be achieved upon completion of the training program and thorough understanding of the surgical protocols.

Comparison of side-to-side anastomosis vs. end-to-end anastomosis in NOSES operation for left colon cancer: a retrospective study

OBJECTIVE

To analyze and compare the application and efficacy of side-to-side anastomosis and end-to-end anastomosis in natural orifice specimen extraction surgery (NOSES) NOSES operation for left colon cancer.

METHODS

A retrospective analysis of 69 patients in our hospital from February 2018 to February 2022 who underwent NOSES for left colon tumors. The observation group was performed with side-to-side anastomosis (Overlap). For digestive tract reconstruction, the control group was anastomosed by end-to-end anastomosis; the intraoperative and postoperative conditions and complications were compared between the two groups.

RESULTS

There was no significant difference in operation time and intraoperative blood loss between the two groups (P > 0.05). However, the intraoperative anastomosis time in the observation group was significantly shorter than that in the control group (P < 0.001). Additionally, there was no significant difference in the time of first exhaustion, defecation time, degree of patency of defecation, frequency of defecation, postoperative hospital stays and postoperative pain between the two groups (P > 0.05). Furthermore, the overall incidence of postoperative complications did not show a significant difference (P > 0.05).

CONCLUSIONS

In the NOSES surgery of left colon cancer, both side-to-side anastomosis (Overlap) and end-to-end anastomosis yielded comparable intraoperative and postoperative conditions and complications, but the side-to-side anastomosis (Overlap) method was simpler operation-wise and had a shorter intraoperative anastomosis time. As such, this method is the preferred anastomosis method when NOSES for colorectal cancer is carried out in primary hospitals.

TRIAL REGISTRATION NUMBER

ChiCTR1900026104 (2019-09-21).

Comparison of laparoscopic versus robot-assisted sugery for rectal cancer after neo-adjuvant therapy: a large volume single center experience

PURPOSE

This study aims to assess the short- and long-term outcomes of rectal cancer patients undergoing robotic versus laparoscopic surgery after receiving neo-adjuvant therapy. There is a lack of clarity on this topic, necessitating a comprehensive comparison.

METHOD

Between January 2017 and December 2021, consecutive patients who underwent laparoscopic and robotic rectal resection at a major public medical center were enrolled. All participants received neo-adjuvant chemoradiotherapy (nCRT) before surgery. The primary objective of this study was to assess the sphincter preservation rate and the rate of conversion to open surgery, using propensity score matching (PSM) analysis. Secondary endpoints included 5-year disease-free survival (DFS), 5-year overall survival (OS), short-term postoperative complications, long-term oncological prognosis, and the occurrence of low anterior resection syndrome (LARS).

RESULT

A total of 575 patients diagnosed with rectal cancer participated in the cohort study, with 183 individuals undergoing robotic surgery and 392 undergoing laparoscopic surgery. Patients in the robotic group tended to be younger and had higher ypT, cT, and cN stages, lower tumor locations, and higher rates of extramural vascular invasion (EMVI) and circumferential resection margin (CRM) positivity. PSM resulted in 183 patients in the robotic group and 187 in the laparoscopic group. We found a higher sphincter preservation rate in robotic group compared with laparoscopic group (92.9% vs. 86.1%, P = 0.033), with no significant difference in conversion to open surgery(P > 0.05). The robotic group had a higher incidence of postoperative chylous ascites (4.9% vs. 1.1%, P = 0.029) and potentially lower sepsis occurrence (0% vs. 1.6%, P = 0.085). No significant differences were observed in long-term oncological prognosis or 5-year survival rates (P > 0.05). The median survival time for each group was 34 months. Subgroup analysis of 76 rectal cancer patients who underwent intersphincteric resection (ISR) surgery indicated that those who selected robotic surgery had higher cN and cT stages. Furthermore, no statistically significant differences were observed in short-term and long-term clinical outcomes, LARS, OS time, and DFS time between the two surgical modalities. The primary outcomes of interest, specifically the rate of sphincter preservation and the rate of conversion to open laparotomy, showed no significant differences.

CONCLUSION

Robotic surgery for rectal cancer, following preoperative nCRT, demonstrates comparable technical safety and oncological outcomes to laparoscopic surgery. Further comprehensive studies are needed to to confirm the potential advantages of robotic surgical interventions.

Impact of PD1 blockade added to neoadjuvant chemoradiotherapy on rectal cancer surgery: post-hoc analysis of the randomized POLARSTAR trial

BACKGROUND

The addition of PD1 blockade to neoadjuvant chemoradiotherapy (CRT) has been shown to significantly increase pCR rates in locally advanced rectal cancer (LARC). Yet, its impact on total mesorectal excision (TME) remains unknown.

METHODS

A post-hoc analysis of the randomized POLARSTAR trial, which enrolled patients with LARC at eight major colorectal cancer centres in Beijing to compare neoadjuvant CRT plus PD1 blockade with CRT alone, was undertaken. Patients received one of three combinations of neoadjuvant treatments before TME surgery: CRT plus concurrent PD1 blockade (concurrent group), CRT plus sequential PD1 blockade (sequential group), and CRT alone (control group). Several parameters related to TME surgery were studied.

RESULTS

For the concurrent group, the sequential group, and the control group, 52, 46, and 45 patients respectively were included in this analysis. The proportion of patients undergoing sphincter-saving plus one-stage anastomosis surgery was 92% (48 of 52), 96% (44 of 46), and 87% (39 of 45) respectively. The proportion of patients without a stoma was 21% (11 of 52), 17% (8 of 46), and 11% (5 of 45) respectively. The grade 3/4 surgical complication rate was 4% (2 of 52), 7% (3 of 46), and 4% (2 of 45) respectively. Significant differences were observed between the sequential group and the control group with respect to the proportion of patients with TRG0 (37% versus 18% respectively; P = 0.040), ypT0/is ypN0 (39% versus 20% respectively; P = 0.046), and a low neoadjuvant rectal (NAR) score (54% versus 31% respectively; P = 0.025).

CONCLUSIONS

Neoadjuvant CRT plus PD1 blockade enhances pathological tumour regression and is beneficial to the successful implementation of TME in patients with LARC. Validations with larger sample sizes are warranted.

The prognostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in colorectal cancer and colorectal anastomotic leakage patients: a retrospective study

OBJECTIVE

The purpose of this study was to investigate the influence and predictive value of preoperative peripheral blood neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) index on the prognosis of colorectal anastomotic leakage (CAL) patients.

METHODS

This study retrospectively analyzed the clinical data of 1016 patients who underwent radical resection for colorectal cancer at a single center between January 1, 2007 and December 31, 2023. In this study, NLR and PLR were analyzed before surgery. Kaplan-Meier survival analysis was performed according to the postoperative survival status of the patients. Nomogram and calibration curve were established by proportional hazards model (COX) to verify its predictive value.

RESULTS

A total of 890 patients with colorectal cancer, 102 patients with CAL, and 788 patients with non- anastomotic leakage (AL) colorectal cancer were enrolled for a median follow-up of 96 months (quartile range 33-133). In this study, COX regression analysis showed that preoperative NLR and PLR could predict the prognosis of CAL patients, and the optimal cut-off points of NLR and PLR were 2.89 and 157.62, respectively. Kaplan-Meier survival curve results showed that 5-year overall survival (OS) and disease-free survival (DFS) in the low NLR and PLR group were significantly higher than those in the high NLR and PLR group. OS and DFS were divided into high, low NLR and PLR groups. Finally, based on COX model, a nomogram analysis was conducted to analyze the risk factors affecting OS and DFS, and the accuracy and practicality of the model were verified by calibration curve and decision curve.

CONCLUSION

Preoperative NLR and PLR can predict the long-term prognosis of colorectal cancer (CRC) and CAL patients, and patients with NLR ≥ 2.89 and PLR ≥ 157.62 have poor survival prognosis. Nomogram and calibration curve analysis will further improve the accuracy of OS and DFS prediction.

Is clinical complete response as accurate as pathological complete response in patients with mid-low locally advanced rectal cancer?

PURPOSE

The standard treatment for locally advanced rectal cancer involves neoadjuvant chemoradiation followed by total mesorectal excision surgery. A subset of patients achieves pathologic complete response (pCR), representing the optimal treatment outcome. This study compares the long-term oncological outcomes of patients who achieved pCR with those who attained clinical complete response (cCR) after total neoadjuvant therapy, managed using a watch-and-wait approach.

METHODS

This study retrospectively evaluated patients with mid-low locally advanced rectal cancer who underwent neoadjuvant treatment from January 1, 2005, to May 1, 2023. The pCR and cCR groups were compared based on demographic, clinical, histopathological, and long-term survival outcomes.

RESULTS

The median follow-up times were 54 months (range, 7-83 months) for the cCR group (n=73), 96 months (range, 7-215 months) for the pCR group (n=63), and 72 months (range, 4-212 months) for the pathological incomplete clinical response (pICR) group (n=627). In the cCR group, 15 patients (20.5%) experienced local regrowth, and 5 (6.8%) developed distant metastasis (DM). The pCR group had no cases of local recurrence, but 3 patients (4.8%) developed DM. Among the pICR patients, 58 (9.2%) experienced local recurrence, and 92 (14.6%) had DM. Five-year disease-free survival rates were 90.0% for cCR, 92.0% for pCR, and 69.5% for pICR (P=0.022). Five-year overall survival rates were 93.1% for cCR, 92.0% for pCR, and 78.1% for pICR. There were no significant differences in outcomes between the cCR and pCR groups (P=0.810); however, the pICR group exhibited poorer outcomes (P=0.002).

CONCLUSIONS

This study shows no significant long-term oncological differences between patients who exhibited cCR and those who experienced pCR.

The Review of Modified Intersphincteric Resection in the Treatment of Ultra-Low Rectal Cancer

OPINION STATEMENT

Colorectal cancer is the third leading cause of cancer death worldwide. In China, the incidence and mortality of colorectal cancer are increasing, in which low rectal cancer is more common. Ultra-low rectal cancer refers to rectal cancer where the distance between the tumor and the anus is less than 5 cm, it accounts for about 70%-80% of rectal tumors. Intersphincteric resection (ISR), an important technical means for anal preservation of ultra-low rectal cancer, although could reduce the pain of patients during the surgical process, increase the anal preservation rate of patients and improve the life quality of patients, still has many adverse effects such as the high incidence of anorectal anastomotic leakage and high anterior resection syndrome. Many modified ISRs have emerged due to the limitations and adverse reactions of traditional ISR surgery. the purpose of this article is to review the progress of ISR surgery to improve its use in treatment.

First clinical report of the international single-port robotic rectal cancer registry

BACKGROUND

Rectal cancer surgery remains a significant technical challenge. The development and implementation of a new technology offer hope for more accurate and precise surgery. To evaluate whether single-port robotic (SPr) technology helps achieve this goal, an international SPr registry was established. This study reported short-term clinical and oncologic outcomes from an international SPr registry for rectal cancer.

METHODS

A review of a prospective international registry of SPr technology approved for colorectal surgery with an investigational design exemption was conducted. Patients with rectal adenocarcinoma who had resection for curative intent using the SPr platform between November 2018 and September 2022 were included. Frequency statistics described patient and tumor characteristics and intraoperative, oncologic, and clinical outcome variables. The main outcome measure was the quality of the total mesorectal excision (TME) specimen. The secondary outcome measures were intraoperative conversion and 30-day postoperative morbidity and mortality.

RESULTS

A total of 113 SPr procedures for rectal cancer were performed at 2 centers by 4 colorectal surgeons. Of note, 9 local excisions were excluded, leaving 104 cases analyzed. The cohort consisted of 53 men (50.96%), had a mean age of 60.00 years (SD, 11.29), and had a body mass index of 25.80 kg/m2 (SD, 6.18). The most common T stage was 3 (55 [52.8%]), followed by 2 (19 [18.26%]). More than 60% of patients had preoperative neoadjuvant chemoradiation. The mean tumor distance from the anorectal ring was 2.90 cm (SD, 2.62), and the mean tumor size was 4.52 cm (SD, 1.82). The procedures performed included transanal abdominal transanal/transanal TME (52 [46%]), low anterior resection (49 [43.3%]), and abdominoperineal resection (3 [2.7%]). The mean operating time was 168.0 min (SD, 56.9). There were no intraoperative complications and 2 (1.9%) conversions to laparoscopy. There was a median of 2 incisions, with a mean size of 2.30 cm (SD, 1.31). The TME specimens were complete in 101 cases (97.1%) and near complete in 3 cases (2.9%). The R1 rate was 3.8%, with 3 positive distal margins and 1 positive circumferential margin. Postoperatively, there were 15 total complications, of which 4 were major complications and 11 were minor complications. There were 2 readmissions (ileus and small bowel obstruction). There were no mortalities.

CONCLUSION

This early international experience with the SPr procedure showed that it is a safe and effective technique for distal rectal cancers, with excellent specimen quality. The complication and conversion rates observed with other techniques and platforms used in rectal cancer surgery were not demonstrated. An international registry was used to better understand the opportunities and limitations of SPr technology in rectal cancer surgery as the technology is adopted and applied more widely. Although structured training and controlled trials will be required to develop best practices and define the use of the SPr technology, initial international registry data are encouraging.

Comparison of postoperative inflammatory response between natural orifice specimen extraction surgery and conventional laparoscopy in the treatment of colorectal cancer: a meta-analysis and systematic review

PURPOSE

Natural orifice specimen extraction surgery (NOSES) has attracted attention because of its minimal invasiveness. This meta-analysis compared inflammatory response profiles and infectious complications between colorectal cancer patients treated with NOSES and those treated with conventional laparoscopy.

METHODS

Seven medical databases were searched up to February 2024. The authors included studies that examined changes in the inflammatory response and outcomes in the patients after NOSES surgery. The Cochrane tool and the Newcastle-Ottawa Scale were used to evaluate the quality of the studies. Pooled standardized mean differences and odds ratios with 95% CIs were calculated using either fixed- or random-effects models. Review Manager 5.4 (RevMan 5.4) and the R project were used for the meta-analysis.

RESULTS

This meta-analysis included 22 studies. Pooled analyses revealed lower tumor necrosis factor-α levels (SMD=-1.34,95% CI [-2.43, -0.25]; Z=2.40, P =0.02 and SMD =-1.49,95% CI [-2.15, -0.82]; Z=4.36, P <0.0001) and C reactive protein levels (SMD=-0.56, 95% CI [-4.17, -2.50]; Z=2.19, P =0.03 and SMD =-1.24,95% CI [-1.77, -0.71]; Z=4.56, P <0.00001) on postoperative day 1 and postoperative day 3 for NOSES than for conventional laparoscopy. Pooled analysis revealed significantly lower interleukin-6 levels in the NOSES group (SMD=-1.88,95% CI [-2.84, -0.93]; Z=3.88, P =0.0001) on postoperative day 3. There were no significant differences in white blood cell count, procalcitonin levels, or the incidence of infectious complications between the two groups.

CONCLUSIONS

NOSES has a superior inflammatory profile and does not increase the incidence of postoperative infectious diseases. The reported results should be validated in a larger population of colorectal cancer patients.

Robotic surgery versus laparoscopic surgery for rectal cancer: a comparative study on surgical safety and functional outcomes

BACKGROUNDS

This study aims to evaluate the clinical efficacy and functional outcomes of DA Vinci (Xi)-assisted surgery compared to conventional laparoscopic surgery for middle and low rectal cancer, focusing on oncologic cure and functional preservation.

METHODS

Between December 2020 and June 2021, 102 patients with middle and low rectal cancer (tumour lower margin ≤10 cm) were enrolled at the affiliated Hospital of Xuzhou Medical University. Participants were divided into two groups: robot-assisted (n = 51) and laparoscopy-assisted (n = 51). Each group underwent a radical resection using their assigned method. Clinical and functional outcomes were analysed post-surgery.

RESULTS

Preoperative data did not differ significantly between groups (P > 0.05). All surgeries were successfully completed without conversion to open surgery. The robotic group experienced significantly less intraoperative blood loss (55.2 ± 29.8 mL vs. 109.5 ± 58.5 mL) and faster recovery in gastrointestinal function (35.1 ± 9.4 h vs. 40.7 ± 1.9 h), diet recovery (2.1 ± 0.8 days vs. 2.9 ± 0.4 days), and catheter removal (2.9 ± 2.7 days vs. 5.3 ± 2.1 days). The robotic group also dissected more lymph nodes (23 ± 6 vs. 15 ± 4). However, they had longer operative times (239.8 ± 29.6 min vs. 141.1 ± 18.5 min) and higher hospital costs. Satisfaction levels regarding defecation, voiding, and sexual functions were notably higher in the robotic group.

CONCLUSION

No significant differences in surgical safety or immediate postoperative outcomes were observed between robotic and laparoscopic approaches. However, robotic surgery demonstrated superior lymph node dissection, anal function preservation, and gastrointestinal recovery, enhancing overall functional outcomes.

Comparison of Renal Tubular Damage with Kidney Injury Molecule-1 in Open and Laparoscopic Colorectal Cancer Surgery

Background and Objectives: Colorectal cancer is the third most common type of cancer in men and women. With advancements in technology, minimally invasive treatment options have become increasingly prominent in colorectal cancer surgery. This study aimed to compare the increased intra-abdominal pressure in laparoscopic colon and rectal surgery with open procedures using kidney injury molecule-1 (KIM-1) secreted from renal tubules. Materials and Methods: We enrolled 46 patients diagnosed with colon cancer who underwent laparoscopic and open surgical procedures at our clinic. The patients were prospectively randomized into five groups: 10 laparoscopic right hemicolectomies (Group 1), 8 open right hemicolectomies (Group 2), 8 laparoscopic anterior resections (LARs) (Group 3), 11 open anterior resections (Group 4), and 9 laparoscopic low anterior resections (Group 5). Urine samples were collected from the patients preoperatively, postoperatively at the 4th hour, and postoperatively on the 14th day, and the urine KIM-1 levels and urine creatinine (Cr) values were measured. The urine KIM-1/Cr ratios were subsequently calculated. Results: The urinary KIM-1/Cr levels increased at the 4th postoperative hour after the open and laparoscopic procedures. On postoperative day 14, the urinary KIM-1/Cr levels were lower than those in the preoperative period in all groups, except the LAR group. Conclusions: Our study shown that the average pressure in laparoscopic colon and rectal surgery did not have a long-term impact on kidney injury in comparison to open colon and rectal surgery.

Prognostic value of preoperative D-dimer to albumin ratio in patients with locally advanced rectal cancer after neoadjuvant chemoradiotherapy

BACKGROUND

The prognostic value of Albumin and D-dimer has been established for multiple tumor types, indicating their potential for predicting tumor development. Nevertheless, the predictive capability of the DDI-to-albumin ratio (DAR) in locally advanced rectal cancer (LARC) remains uncertain.

PURPOSE

The objective of this study was to investigate the prognostic significance of the DAR in LARC.

METHODS

A total of 513 patients who underwent neoadjuvant chemoradiotherapy (nCRT) prior to total mesorectal excision (TME) between March 2013 to October 2019 were included in this study. Patients were divided into high-level DAR (> 0.016) or low-level DAR (≤ 0.016) groups based on ROC curve analysis optimum cut-off value. The prognostic value of the DAR in LARC was analyzed.

RESULTS

The study enrolled 513 patients. Patients were stratified into high-level DAR (> 0.016) and low-level DAR (≤ 0.016) cohorts according to the optimal cut-off value determined by ROC curve analysis. The 5-year overall survival (OS) rates for patients in the low DAR group (≤ 0.016) and the high DAR group (> 0.016) were 89.4% and 80.9%, respectively (p = 0.013). The 5-year disease-free survival (DFS) rates were 85.7% and 77.4% (p = 0.027). Multivariate analyses demonstrated that DAR were independent prognostic factors for OS (p = 0.02) and DFS (0.025). Predictive nomograms that included the DAR score group (C-index: OS-0.743, DFS-0.705) were superior to those without DAR scores (C-index: OS-0.721, DFS-0.697).

CONCLUSION

The DAR demonstrates high usability and prognostic value in predicting OS and DFS outcomes among patients diagnosed with LARC who undergo nCRT.

Analysis of the correlation between defunctioning stoma and postoperative low anterior resection syndrome in rectal cancer: a prospective cohort study

BACKGROUND

To evaluate the effect of stoma-related factors (stoma or no stoma, stoma type, and stoma reversal time) on the occurrence of low anterior resection syndrome (LARS), a highly prevalent condition that can develop after anal sphincter-sparing surgery for rectal cancer and impair quality of life, which includes fecal incontinence, fecal urgency and frequent defecation.

METHODS

Patients who underwent radical rectal cancer surgery from July 2018 to July 2022 in a tertiary hospital were included. Baseline data, tumor condition, operation condition and postoperative recovery were obtained by clinical observation. Follow-up data were collected by telephone follow-up. The chi-square and Fisher exact tests were used to analyse differences, coefficient of contingency was used to determine correlations, and independent risk factors for the occurrence of LARS (Patients with a score of 21 or more points were defined as having LARS using the LARS score) were further determined by binary logistic regression.

RESULTS

A total of 480 patients met the inclusion criteria, of which 267 used a defunctioning stoma and 213 did not use a defunctioning stoma. There was a positive correlation between defunctioning stoma (P < 0.001, P < 0.001, P < 0.05) and the occurrence of LARS at 3, 6, and 12 months postoperatively, and there was no significant correlation between the stoma type or stoma reversal time and the occurrence of LARS at 3, 6 and 12 months postoperatively (P > 0.05). In binary logistic regression analysis, high BMI (Exp(B) = 1.072, P = 0.039), tumor closer to dentate line (Exp(B) = 0.910, P = 0.016), and ultra-low anterior resection (Exp(B) = 2.264, P = 0.011) increased the possibility of LARS at 3 months postoperatively; high BMI, proximity of the tumor to the dentate line, and ultra-low anterior resection were not independent risk factors for LARS at 6 months postoperatively (P > 0.05). However, proximity of the tumor to the dentate line (Exp(B) = 0.880, P = 0.035) increased the likelihood of LARS at 12 months postoperatively, while high BMI and ultra-low anterior resection remained non-significant as independent risk factors for LARS at 12 months postoperatively (P > 0.05).

CONCLUSIONS

Defunctioning stoma was not an independent risk factor for the occurrence of LARS, whereas high BMI, tumor closer to dentate line, and ultra-low anterior resection were independent risk factors for the occurrence of LARS.

TRIAL REGISTRATION

Not applicable.

Robotic surgery is associated with a decreased risk of circumferential resection margin positivity compared with conventional laparoscopic surgery in patients with rectal cancer undergoing mesorectal excision: A systematic review and meta-analysis

OBJECTIVE

To investigate whether robotic surgery (RS) decreases the risk of circumferential resection margin (CRM) positivity compared with conventional laparoscopic surgery (LS) in patients with rectal cancer (RC) undergoing mesorectal excision (ME).

BACKGROUND

Although it is well known that CRM positivity affects postoperative outcomes in patients with RC undergoing ME, few studies have investigated whether RS is superior to conventional LS for the risk of CRM positivity.

METHODS

We performed a comprehensive electronic search of the literature up to December 2022 to identify studies that compared the risk of CRM positivity between patients with RC undergoing robotic and conventional laparoscopic surgery. A meta-analysis was performed using random-effects models to calculate risk ratios (RRs) and 95 % confidence intervals (CIs), and heterogeneity was analyzed using I2 statistics.

RESULTS

Eighteen studies, consisting of 4 randomized controlled trials (RCTs) and 14 propensity score matching (PSM) studies, involved a total of 9203 patients with RC who underwent ME were included in this meta-analysis. The results demonstrated that RS decreased the overall risk of CRM positivity (RR, 0.82; 95 % CI, 0.73-0.92; P = 0.001; I2 = 0 %) compared with conventional LS. Results of a meta-analysis of the 4 selected RCTs also showed that RS decreased the risk of CRM positivity (RR, 0.62; 95 % CI, 0.43-0.91; P = 0.01; I2 = 0 %) compared with conventional LS.

CONCLUSIONS

This meta-analysis revealed that RS is associated with a decreased risk of CRM positivity compared with conventional LS in patients with RC undergoing ME.

Deep pelvis and low visceral fat mass as risk factors for neurogenic bladder after rectal cancer surgery

BACKGROUND

Postoperative neurogenic bladder (PONB) frequently occurs as a complication after rectal cancer surgery. This study aimed to analyze risk factors for developing PONB after rectal cancer surgery, particularly the association between pelvic anatomy and visceral fat mass.

METHODS

We included 138 patients who underwent rectal resection for lower rectal cancer in our department between 2017 and 2021. PONB was defined as the need for urethral catheter reinsertion or oral medication administration for urinary retention after catheter removal with severe NB that required treatment for ≥ 60 days. We obtained visceral fat area (VFA) at the umbilical level based on a CT scan and measured five pelvic dimensions.

RESULTS

Of the 138 patients, 19 developed PONB, with 16 being severe cases. PONB more frequently occurs in patients with a height of < 158 cm, age ≥ 70 years, surgery lasting ≥ 8 h, intraoperative bleeding volume ≥ 150 mL, lateral lymph node dissection, and narrower pelvis. It was more prevalent in cases with low VFA. Conversely, gender, body mass index (BMI), and medical history showed no significant correlations. Multivariate analysis revealed older age, prolonged surgery, and low VFA as independent risk factors for PONB. Independent risk factors for severe PONB included low VFA, older age, prolonged surgery, and deep pelvis.

CONCLUSION

Lower VFA, older age, and prolonged surgery are independent risk factors for developing PONB. Additionally, a deep pelvis is an independent risk factor for severe PONB. Delicate surgical techniques should consider the risk of nerve injury in cases with low VFA and deep pelvis.

Conversion to open surgery in obese patients undergoing minimally invasive distal pancreatectomy: results from a multicenter analysis

BACKGROUND

Although minimally invasive distal pancreatectomy (MIDP) is considered a standard approach it still presents a non-negligible rate of conversion to open that is mainly related to some difficulty factors, as obesity. The aim of this study is to analyze the preoperative factors associated with conversion in obese patients with MIDP.

METHODS

In this multicenter study, all obese patients who underwent MIDP at 18 international expert centers were included. The preoperative factors associated with conversion to open surgery were analyzed.

RESULTS

Out of 436 patients, 91 (20.9%) underwent conversion to open, presenting higher blood loss, longer operative time and similar rate of major complications. Twenty (22%) patients received emergent conversion. At univariate analysis, the type of approach, radiological invasion of adjacent organs, preoperative enlarged lymphnodes and ASA ≥ III were significantly associated with conversion to open. At multivariate analysis, robotic approach showed a significantly lower conversion rate (14.6 % vs 27.3%, OR = 2.380, p = 0.001). ASA ≥ III (OR = 2.391, p = 0.002) and preoperative enlarged lymphnodes (OR = 3.836, p = 0.003) were also independently associated with conversion.

CONCLUSION

Conversion rate is significantly lower in patients undergoing robotic approach. Radiological enlarged lymphnodes and ASA ≥ III are also associated with conversion to open. Conversion is associated with poorer perioperative outcomes, especially in case of intraoperative hemorrhage.

The role of superior hemorrhoidal vein ectasia in the preoperative staging of rectal cancer

Objective

The prognosis of colorectal cancer has continuously improved in recent years thanks to continuous progress in both the therapeutic and diagnostic fields. The specific objective of this study is to contribute to the diagnostic field through the evaluation of the correlation between superior hemorrhoidal vein (SHV) ectasia detected on computed tomography (CT) and Tumor (T), Node (N), and distant metastasis (M) examination and mesorectal fascia (MRF) invasion in the preoperative staging of rectal cancer.

Methods

Between January 2018 and April 2022, 46 patients with histopathological diagnosis of rectal cancer were retrospectively enrolled, and the diameter of the SHV was evaluated by CT examination. The cutoff value for SHV diameter used is 3.7 mm. The diameter was measured at the level of S2 during portal venous phase after 4× image zoom to reduce the interobserver variability. The parameters evaluated were tumor location, detection of MRF infiltration (defined as the distance < 1 mm between the tumor margins and the fascia), SHV diameter, detection of mesorectal perilesional lymph nodes, and detection of metastasis.

Results

A total of 67.39% (31/46) of patients had SHV ectasia. All patients with MRF infiltration (4/46, 7.14%) presented SHV ectasia (average diameter of 4.4 mm), and SHV was significantly related with the development of liver metastases at the moment of primary staging and during follow-up.

Conclusion

SHV ectasia may be related to metastasis and MRF involvement; therefore, it could become a tool for preoperative staging of rectal cancer.

Comparing total mesorectal excision with partial mesorectal excision for proximal rectal cancer: evaluating postoperative and long-term oncological outcomes

The treatment role of Total Mesorectal Excision (TME) in proximal rectal cancers (PRC) is still debated. Partial Mesorectal Excision (PME) can reduce morbidity in PRC patients. The purpose of this study was to compare short-term clinical and long-term oncological outcomes between the two groups. A total of 157 PRC patients were enrolled in this study (114 performed with PME and 43 with TME). The two groups were compared in terms of perioperative and long-term oncological outcomes. The overall postoperative complications rate was higher in TME group (18.4% vs. 32.5%, p < 0.05). The incidence of diverting ileostomy was also significantly higher in TME group (86.0% vs. 2.6%, p < 0.001). Overall survival rates for 3, 5, and 7 years in PME and TME group accordingly were: 94.6%, 89.3%, 81.5% and 93.2%, 87.6%, 78.4% (p = 0.324). Disease-free survival rates for 3, 5, and 7 years in PME and TME group were: 90.2%, 84.5%, 78.6% and 88.7%, 81.2%, 75.3% (p = 0.297), respectively. Local recurrence rates for 3, 5, and 7 years in PME and TME group were: 2.6%, 6.1%, 8.8% and 4.6%, 9.3%, 11.2% (p = 0.061), respectively. PME is feasible and can be safely performed in PRC patients with favorable oncological outcomes. TME is associated with increasing risk of surgical complications and requires a two-step surgery for stoma takedown.

Long-Term Outcomes of Robotic Versus Laparoscopic Total Mesorectal Excisions: A Propensity-Score Matched Cohort study of 5-year survival outcomes

Objective

To compare long-term outcomes between laparoscopic and robotic total mesorectal excisions (TMEs) for rectal cancer in a tertiary center.

Background

Laparoscopic rectal cancer surgery has comparable long-term outcomes to the open approach, with several advantages in short-term outcomes. However, it has significant technical limitations, which the robotic approach aims to overcome.

Methods

We included patients undergoing laparoscopic and robotic TME surgery between 2013 and 2021. The groups were compared after propensity-score matching. The primary outcome was 5-year overall survival (OS). Secondary outcomes were local recurrence (LR), distant recurrence (DR), disease-free survival (DFS), and short-term surgical and patient-related outcomes.

Results

A total of 594 patients were included, and after propensity-score matching 215 patients remained in each group. There was a significant difference in 5-year OS (72.4% for laparoscopy vs 81.7% for robotic, P = 0.029), but no difference in 5-year LR (4.7% vs 5.2%, P = 0.850), DR (16.9% vs 13.5%, P = 0.390), or DFS (63.9% vs 74.4%, P = 0.086). The robotic group had significantly less conversion (3.7% vs 0.5%, P = 0.046), shorter length of stay [7.0 (6.0-13.0) vs 6.0 (4.0-8.0), P < 0.001), and less postoperative complications (63.5% vs 50.7%, P = 0.010).

Conclusions

This study shows a correlation between higher 5-year OS and comparable long-term oncological outcomes for robotic TME surgery compared to the laparoscopic approach. Furthermore, lower conversion rates, a shorter length of stay, and a less minor postoperative complications were observed. Robotic rectal cancer surgery is a safe and favorable alternative to the traditional approaches.

Determining the optimal distal resection margin in rectal cancer patients by imaging of large pathological sections: An experimental study

OBJECTIVE

To determine the distal resection margin in sphincter-sparing surgery in patients with low rectal cancer based on imaging of large pathological sections.

METHODS

Patients who underwent sphincter-sparing surgery for ultralow rectal cancer at Guangxi Medical University Cancer Hospital within the period from January 2016 to March 2022 were tracked and observed. The clinical and pathological data of the patients were collected and analyzed. The EVOS fluorescence automatic cell imaging system was used for imaging large pathological sections. Follow-up patient data were acquired mainly by sending the patients letters and contacting them via phone calls, and during outpatient visits.

RESULTS

A total of 46 patients (25 males, 21 females) aged 27 to 86 years participated in the present study. Regarding clinical staging, there were 9, 10, 16, and 10 cases with stages I, II, III, and IV low rectal cancer, respectively. The surgical time was 273.82 ± 111.51 minutes, the blood loss was 123.78 ± 150.91 mL, the postoperative exhaust time was 3.67 ± 1.85 days, and the postoperative discharge time was 10.36 ± 5.41 days. There were 8 patients with complications, including 3 cases of pulmonary infection, 2 cases of intestinal obstruction, one case of pleural effusion, and one case of stoma necrosis. The longest and shortest distal resection margins (distances between the cutting edges and the tumor edges) were 3 cm and 1 cm, respectively. The minimum length of the extension areas of the tumor lesions in the 46 images of large pathological sections was 0.1 mm, and the maximum length was 15 mm. Among the tumor lesions, 91.30% (42/46) had an extension area length of ≤5 mm, and 97.83% (45/46) had an extension area length of ≤10 mm. The length of the extension zone was not related to clinical pathological parameters (P > .05).

CONCLUSION

In the vast majority of cases, the distal resection margin was at least 1 cm; thus, "No Evidence of Disease" could have been achieved. Additional high-powered randomized trials are needed to confirm the results of the present study.

Development and validation of machine learning models and nomograms for predicting the surgical difficulty of laparoscopic resection in rectal cancer

BACKGROUND

The objective of this study is to develop and validate a machine learning (ML) prediction model for the assessment of laparoscopic total mesorectal excision (LaTME) surgery difficulty, as well as to identify independent risk factors that influence surgical difficulty. Establishing a nomogram aims to assist clinical practitioners in formulating more effective surgical plans before the procedure.

METHODS

This study included 186 patients with rectal cancer who underwent LaTME from January 2018 to December 2020. They were divided into a training cohort (n = 131) versus a validation cohort (n = 55). The difficulty of LaTME was defined based on Escal's et al. scoring criteria with modifications. We utilized Lasso regression to screen the preoperative clinical characteristic variables and intraoperative information most relevant to surgical difficulty for the development and validation of four ML models: logistic regression (LR), support vector machine (SVM), random forest (RF), and decision tree (DT). The performance of the model was assessed based on the area under the receiver operating characteristic curve(AUC), sensitivity, specificity, and accuracy. Logistic regression-based column-line plots were created to visualize the predictive model. Consistency statistics (C-statistic) and calibration curves were used to discriminate and calibrate the nomogram, respectively.

RESULTS

In the validation cohort, all four ML models demonstrate good performance: SVM AUC = 0.987, RF AUC = 0.953, LR AUC = 0.950, and DT AUC = 0.904. To enhance visual evaluation, a logistic regression-based nomogram has been established. Predictive factors included in the nomogram are body mass index (BMI), distance between the tumor to the dentate line ≤ 10 cm, radiodensity of visceral adipose tissue (VAT), area of subcutaneous adipose tissue (SAT), tumor diameter >3 cm, and comorbid hypertension.

CONCLUSION

In this study, four ML models based on intraoperative and preoperative risk factors and a nomogram based on logistic regression may be of help to surgeons in evaluating the surgical difficulty before operation and adopting appropriate responses and surgical protocols.

Perioperative and long-term oncological outcomes of robotic versus laparoscopic total mesorectal excision: a retrospective study of 672 patients

Although there's growing information about the long-term oncological effects of robotic surgery for rectal cancer, the procedure is still relatively new. This study aimed to assess the long-term oncological results of total mesorectal excision (TME) performed laparoscopically versus robotically in the setting of rectal cancer. Restrospective analysis of a prospectively maintained database. A total of 489 laparoscopic (L-TME) and 183 robotic total mesorectal excisions (R-TME) were carried out by a single surgeon between 2013 and 2023. The groups were compared in terms of perioperative and long-term oncological outcomes. In the R-TME and L-TME groups, male sex predominated (75.4% and 57.3%, respectively), although the robotic group was significantly greater (p = 0.008). There was no conversion in R-TME group, whereas three (0.6%) converted to open surgery in L-TME group. The R-TME group had a statistically significant higher number of distal rectal tumors (85%) compared to the L-TME group (54.6%). Only three (1.7%) patients in the R-TME group received abdomineperineal resection (APR); in contrast, 25 (5%) patients in the L-TME group received APR (p < 0.001). For R-TME, the mean follow-up was 70.7 months (range 18-138) and for L-TME, it was 60 months (range 14-140). Frequency of completed mesorectum was significantly greater in R-TME group (98.9% vs 94.2%, p < 0.001). The 5 year overall survival rates for R-TME and L-TME groups were 89.6% and 88.7%, respectively. The 5 year disease-free survival for R-TME and L-TME groups were 84.1% and 81.1%, respectively. The local recurrences rates were 7.6% and 6.3%, respectively in R-TME and L-TME groups (p = 0.274). R-TME is characterized by no conversion and improved mesorectal integrity. R-TME had longer operation time. The long-term oncological outcomes were comparable between groups.

Sphincter-preserving effect of robotic-assisted intersphincteric resection for ultra-low rectal cancer: a propensity score matching analysis

Intersphincteric resection (ISR) is a viable option for sphincter preservation in early ultra-low rectal cancer, but postoperative anal dysfunction remains a concern. This study evaluates the outcomes of robotic ISR with coloanal anastomosis in early ultra-low rectal cancer, comparing its efficacy and safety with laparoscopic ISR. Retrospective analysis was conducted on data from 74 consecutive patients undergoing robotic intersphincteric resection (R-ISR) for early ultra-low rectal cancer between January 2017 and December 2018 (R-ISR group), matched with 110 patients undergoing laparoscopic intersphincteric resection (L-ISR). After 1:1 propensity score matching, each group comprised 68 patients. Comparative analyses covered surgical outcomes, complications, long-term results, and anal function. The R-ISR group showed longer total operative time than the L-ISR group (211.7 ± 25.3 min vs. 191.2 ± 23.0 min, p = 0.001), but less intraoperative bleeding (55.2 ± 20.7 ml vs. 69.2 ± 22.9 ml, p = 0.01). R-ISR group had fewer conversions to APR surgery (6/8.8% vs. 14/20.6%). Other perioperative indicators were similar. R-ISR exhibited a smaller tumor margin, superior mesorectal integrity, and comparable histopathological outcomes. Postoperative complications, 3-year and 5-year DFS, and OS were similar. At the 1-year follow-up, the Wexner Incontinence Score favored R-ISR (9.24 ± 4.03 vs. 11.06 ± 3.77, p = 0.048). Although R-ISR prolongs the operative time, its surgical safety and oncological outcomes are similar to conventional ISR procedures. Furthermore, it further shortens the margin of anal preservation, reduces the rate of conversion to APR surgery, and improves postoperative anal function.

Robotic and laparoscopic sphincter-saving resections have similar peri-operative, oncological and functional outcomes in female patients with rectal cancer

BACKGROUND

This study aimed to compare perioperative, long-term oncological, and anorectal functional outcomes of robotic total mesorectal excision (R-TME) and laparoscopic total mesorectal excision (L-TME) sphincter-saving total mesorectal excision in female patients with rectal cancer.

METHODS

Retrospective analysis of prospectively maintained database was performed. Sixty-eight cases (L-TME, n = 34; R-TME, n = 34) were performed by a single surgeon (January 2014-January 2019). Patient characteristics, perioperative recovery, postoperative complications, pathology results, and oncological outcomes were compared between the two groups.

RESULTS

Clinical characteristics did not differ between the groups. Mean operating time was longer in R-TME (165.50 ± 95.50 vs. 124.50 ± 82.60 min, p < 0.001). There was no conversion to open surgery in both groups. Mesorectal integrity was complete in both groups (100%). Length of distal and circumferential resection margins (CRM) did not differ between groups. CRM involvement was observed in 1 (2.8%) and 1 (2.8%) in L-TME and R-TME patients, respectively. Incidence of anastomotic leakage was 5.8% (n = 2) in L-TME and 8.8% (n = 3) in R-TME, respectively. Mean length of follow-up was 62.5 (36-102) months for R-TME and 63 (36-103) months for L-TME. Five-year overall survival rates were 92.8% in L-TME and 89.6% in R-TME. Disease-free survival rates were 87.5% in L-TME and 89.6% in R-TME. Local recurrence rates were 3.0% for both groups. Mean Wexner score for L-TME and R-TME patients was: 9.42 ± 8.23 and 9.22 ± 3.64 (p = 0.685), respectively. Daily stool frequency was similar between groups.

CONCLUSION

Robotic total mesorectal excision (R-TME) and laparoscopic TME (L-TME) have similar perioperative, oncological, and anorectal functional results in female patients with rectal cancer. The robotic approach for rectal cancers in female patients could be not as critical as for male patients.

International standardization and optimization group for intersphincteric resection (ISOG-ISR): modified Delphi consensus on anatomy, definition, indication, surgical technique, specimen description and functional outcome

AIM

Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future.

METHOD

A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol.

RESULTS

Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements.

CONCLUSION

This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.

Robotic Total Mesorectal Excision for Low Rectal Cancer: A Narrative Review and Description of the Technique

Robotic surgery may offer significant advantages for treating extraperitoneal rectal cancer. Although laparoscopy has been shown to be safe and effective, laparoscopic total mesorectal excision (TME) remains technically challenging and is still performed in selected centers. Robotic anterior resection (RAR) may overcome the drawback of conventional laparoscopy, providing high-quality surgery with favorable oncological outcomes. Moreover, recent data show how RAR offers clinical and oncological benefits when affording difficult TMEs, such as low and advanced rectal tumors, in terms of complication rate, specimen quality, recurrence rate, and survival. This series aims to review the most recent and relevant literature, reporting mid- and long-term oncological outcomes and focusing on minimally invasive RAR for low rectal cancer.