In Japan, the hinotori™ Surgical Robot System obtained pharmaceutical approval for use in colorectal cancer surgery in October 2022. This system has an operating arm with eight axes, adjustable arm base, and flexible three-dimensional viewer, which are expected to be advantageous in colorectal cancer surgery. A 55-year-old man presented to our hospital with melena and was diagnosed with cStage IIA (cT3N0M0) rectal cancer. The patient underwent intersphincteric resection using hinotori™ Surgical Robot System. Appropriate port placement was available for rectal manipulation, lymph node dissection, and arm base angle adjustment. Herein, we report the world\'s first rectal cancer surgery using the hinotori™ Surgical Robot System with TaTME by two teams.

BACKGROUND: With steep posterior anorectal angulation, transanal total mesorectal excision (taTME) may have a risk of dissection in the wrong plane or starting higher up, resulting in leaving distal mesorectum behind. Although the distal mesorectal margin can be assessed by preoperative MRI, it needs skilled radiologist and high-definition image for accurate evaluation. This study developed a deep neural network (DNN) to predict the optimal level of distal mesorectal margin.
METHODS: A total of 182 pelvic MRI images extracted from the cancer image archive (TCIA) database were included. A DNN was developed using gender, the degree of anterior and posterior anorectal angles as input variables while the difference between anterior and posterior mesorectal distances from anal verge was selected as a target. The predictability power was assessed by regression values (R) which is the correlation between the predicted outputs and actual targets.
RESULTS: The anterior angle was an obtuse angle while the posterior angle varied from acute to obtuse with mean angle difference 35.5°±14.6. The mean difference between the anterior and posterior mesorectal end distances was 18.6±6.6mm. The developed DNN had a very close correlation with the target during training, validation, and testing (R=0.99, 0.81, and 0.89, P<0.001). The predicted level of distal mesorectal margin was closely correlated with the actual optimal level (R=0.91, P<0.001).
CONCLUSIONS: Artificial intelligence can assist in either making or confirming the preoperative decisions. Furthermore, the developed model can alert the surgeons for this potential risk and the necessity of re-positioning the proctectomy incision.

BACKGROUND: Comparative outcomes of robotic low anterior resection (rTME) and trans-anal total mesorectal excision (TaTME) in patients with low rectal cancer were evaluated.
METHODS: A systematic online search was conducted using the following databases: PubMed, Scopus, Cochrane database, The Virtual Health Library, Clinical trials.gov and Science Direct. Comparative studies of rTME versus TaTME for low rectal cancer were included. Primary outcomes were postoperative complications, including anastomotic leak, surgical site infection, and Clavien-Dindo complication rate. Total operative time, conversion to open surgery, intra-operative blood loss, intensive therapy unit (ITU) and total hospital length of stay (LOS), oncological outcomes and functional outcomes were the other evaluated outcome parameters.
RESULTS: A total of 12 studies with a total number of 3025 patients divided between rTME (n = 1881) and TaTME (n = 1144) groups were included. There was no significant difference between the two groups for total operative time (P = 0.39), conversion to open surgery (P = 0.29) and intra-operative blood loss (P = 0.62). Clavien-Dindo ≥ 3 complication rate (P = 0.47), anastomotic leak (P = 0.89), rates of re-operation (P = 0.62) and re-admission (P = 0.92), R0 resections (P = 0.52), ITU LOS (P = 0.63) and total hospital LOS (P = 0.30) also showed similar results between the two groups. However, the rTME group had higher rates of total harvested lymph nodes (P = 0.04) and complete total mesorectal excision (TME) resections (P = 0.05). Albeit with a limited dataset, the Wexner and low anterior resection syndrome (LARS) scores showed better functional results in the rTME group compared with the TaTME group (P = 0.0009 and P = 0.00001, respectively).
CONCLUSIONS: Compared with TaTME, rTME seems to provide better functional outcomes, higher lymph node yield and more complete TME resections with a similar post-operative complications profile.

UNASSIGNED: To investigate the oncological outcomes after transanal total mesorectal excision (TaTME) for rectal cancer and risk factors for local recurrence (LR).
UNASSIGNED: A high LR rate with a multifocal pattern early after TaTME has been reported in Norway and the Netherlands, causing controversy over the oncological safety of this technique.
UNASSIGNED: Twenty-six member institutions of the Japan Society of Laparoscopic Colorectal Surgery participated in this retrospective cohort study. A total of 706 patients with primary rectal cancer who underwent TaTME between January 2012 and December 2019 were included for analysis. The primary endpoint was the cumulative 3-year LR rate.
UNASSIGNED: A total of 253 patients had clinical stage III disease (35.8%) and 91 (12.9%) had stage IV. Intersphincteric resection was performed in 318 patients (45.0%) and abdominoperineal resection in 193 (27.3%). There was 1 urethral injury (0.1%). A positive resection margin (R1) was seen in 42 patients (5.9%). Median follow-up was 3.42 years, and the 2- and 3-year cumulative LR rates were 4.95% (95% confidence interval: 3.50-6.75) and 6.82% (95% confidence interval: 5.08-8.89), respectively. A multifocal pattern was observed in 14 (25%) of 56 patients with LR. Tumor height from the anal verge, pathological T4 disease, pathological stage III/IV, positive perineural invasion, and R1 resection were significant risk factors for LR in multivariable analysis.
UNASSIGNED: In this selected cohort in which intersphincteric resection or abdominoperineal resection was performed in more than half of cases, oncological outcomes were acceptable during a median follow-up of more than 3 years.

OBJECTIVE: Transanal total mesorectal (taTME) excision is a method used to assist in the radical removal of the rectum. By adopting the concept of natural orifice surgery, it offers potential benefits over conventional techniques. Early enthusiasm for this strategy led to its rapid and widespread adoption. The imposing of a local moratorium was precipitated by the discovery in Norway of an uncommon multifocal pattern of locoregional recurrence. The aim of this systematic review and meta-analysis was to determine the incidence of local recurrence after taTME for rectal cancer.
METHODS: Conforming to the Cochrane Handbook for Systematic Reviews of Interventions and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines checklist, a systematic review and meta-analysis was conducted. This included case series and comparative studies between taTME and preferentially laparoscopic procedures published between 2010 and 2021.
RESULTS: There were a total of 1175 studies retrieved. After removal and screening for quality and relevance, the final analysis contained 40 studies. The local recurrence rate following taTME was 3.4% (95% CI 2.9%-3.9%, I2 = 0%) in 4987 patients with follow-up durations ranging from 0.7 to 5.5 years. Compared with laparoscopic TME, local recurrence was not statistically different for the taTME group (p = 0.076); however, it was less probable (OR = 0.51, 95% CI 0.24-1.09, I2 = 0%). Systemic recurrence and circumferential resection margin status were secondary outcomes; however, the differences were not statistically significant.
CONCLUSIONS: Our data suggest that the local recurrence for regular laparoscopic and transanal TME surgeries may be comparable, suggesting that taTME can be performed without influencing locoregional oncological outcomes in patients treated at specialized institutions and who have been cautiously selected.

Összefoglaló cikkünkben a colon- és rectumcarcinomák sebészeti kezelésében az elmúlt években megjelent új elveket, új ötleteket és technológiákat tekintjük át. A tanulmány narratív összefoglalás, mely tematikusan kiemelt colorectalis sebészeti irodalmi ismeretek gyűjteményét adja két, a colorectalis sebészetben jártas sebész független válogatása alapján. A coloncarcinomák esetében a komplett mesocolon-excisiót (CME), illetve a radikális lymphadenectomiát, a jobb és bal colonfél tumorainak biológiai eltéréseit, valamint a tumorbiológiai jellemzők alapján a neoadjuváns gyógyszeres kezelés lehetőségeit értékeljük. A rectumcarcinomák sebészeti megoldásai közül a transanalis teljes mesorectum-excisio (TaTME), a robotsebészet, az intersphinctericus reszekciók, illetve a lymphadenectomia radikalitásának kérdései, végül a szervkímélő rectumsebészet kerül tárgyalásra. A colon- és a rectumcarcinoma sebészete mára jelentősen eltérő utakra jutott. A technikai, technológiai innováció nyújtotta lehetőségeket a patológiai, onkológiai ismeretekkel összhangban személyre szabott terápiás lehetőségekként indokolt a mindennapokban multidiszciplináris döntés alapján alkalmazni. Orv Hetil. 2024; 165(2): 43–50.

To compare the rate of sphincter-saving interventions between transanal and laparoscopic Total Mesorectal Excision in this particular group of patients. A multicentre observational study was conducted using a prospective database, including patients diagnosed with rectal cancer below the peritoneal reflection and BMI ≥ 30 kg/m2, who underwent minimally invasive elective surgery over a 5-year period. Exclusion criteria were (1) sphincter and/or puborectalis invasion; (2) multi-visceral resections; (3) palliative surgeries. The study population was divided into two groups according to the intervention: transanal or laparoscopic total mesorectal excision. The primary outcome was the rate of sphincter-saving surgery. Secondary outcomes included conversion, postoperative complications, quality of the specimen, and survival. A total of 93 patients were included; 40 (43%) transanal total mesorectal excision were compared to 53 (57%) laparoscopic. In addition, 35 cases of transanal approach were case-matched with an equal number of laparoscopic approaches, based on gender, tumor\'s height, and neoadjuvant therapy. In both groups, 43% of the patients had low rectal cancer; however, the rate of sphincter-saving surgery was significantly higher in the transanal group (97% vs. 71%, p = 0.003). There were no conversions to open surgery in the transanal group, compared to 2 cases in the laparoscopic group (6%) (p = 0.246). The percentage of major complications was similar, including the rate of anastomotic leakage (10% transanal vs. 19% laparoscopic, p = 0.835). In our experience, higher percentages of sphincter-saving procedures and lower conversion rates are potential benefits of using the transanal approach in a complex surgical setting population of obese patients with mid-low rectal tumors when compared to laparoscopic.

UNASSIGNED: A narrow pelvis, obesity, and bulky low rectal tumor are perceived as risk factors for intraoperative difficulties during total mesorectal excision (TME), particularly in the laparoscopic approach. A transanal approach has been developed to overcome the difficulties encountered during laparoscopic TME. There is no clear definition of a narrow pelvis that would guide preoperative surgical planning.
UNASSIGNED: To evaluate different MRI-based pelvic measurements in patients undergoing TME to identify factors predictive of intraoperative difficulties in transabdominal compared to the transanal approach.
UNASSIGNED: A retrospective analysis of 48 patients treated with laparoscopic TME and 62 with transanal TME for rectal tumors was performed. Multiple logistic regressions analyzed demographic, tumor, and pelvimetry factors that correlate with intraoperative difficulties measured as intraoperative blood loss, operation time, and perioperative complications in both surgical approaches.
UNASSIGNED: Multivariate analysis showed that age was associated with higher blood loss (OR = 1.09, 95% CI: 1.00-1.18, p = 0.038), male gender (OR = 0.13, 95% CI: 0.02-0.86, p = 0.029) and body mass index with longer operating time (OR = 1.32, 95% CI: 1.06-1.64, p = 0.010) in the LAR group. Multivariate analysis showed that age increased the odds of intraoperative blood loss > 100 ml (OR = 1.08, 95% CI: 1.02-1.15, p = 0.013), and pelvic length > 119 mm increased operating time (OR = 5.76, 95% CI: 1.33-25.01, p = 0.016) in the TaTME group.
UNASSIGNED: Pelvic measurements are not associated with intraoperative difficulties in LAR. Longer pelvis was associated with longer operative time in TaTME.

BACKGROUND: Rectal cancer is a significant healthcare burden, and effective treatment is crucial. This research aims to compare the effectiveness of surgical and endoscopic resection, transanal resection, and radiotherapy.
METHODS: A literature analysis was conducted in order to identify relevant studies, by comparing the different surgical approaches and variables affecting treatment decisions. The findings were analyzed and synthesized to provide a comprehensive overview.
RESULTS: Surgical treatment, particularly TME (total mesorectal excision), proved consistent efficacy in achieving complete tumor resection and improving long-term survival. Endoscopic treatment and transanal resection techniques were promising for early-stage tumors but were associated with higher local recurrence rates. Radiotherapy, especially in combination with chemotherapy, played a crucial role in locally advanced cases, improving local control and reducing recurrence risk. Patient data, tumor characteristics, and healthcare system factors were identified as important factors in treatment modality selection.
CONCLUSIONS: Surgical treatment, specifically TME, remains the recommended standard approach for rectal cancer, providing excellent oncological outcomes. Endoscopic treatment and transanal resection techniques can be considered for selected early-stage cases, while radiotherapy is beneficial for locally advanced tumors. Treatment decisions should be personalized based on patient and tumor characteristics, considering the available resources and expertise within the healthcare system.

BACKGROUND:  The aim of this study was to determine the incidence of Clostridium Difficile infection (CDI) after stoma reversal in patients who underwent transanal Total Mesorectal Excision (TaTME) and to evaluate variables correlated with this post-operative infection.
METHODS:  Patients who underwent stoma reversal surgery following TaTME for rectal cancer between 2015 and 2023 at a high-volume Institution, were retrospectively reviewed for the post-operative occurrence of diarrhea and in-hospital CDI (positive toxin in the stools). Patients were divided into the following subgroups according to the post-operative course: Group A-no clinical symptoms; Group B-mild diarrhea (< 10 evacuations/day); Group C-severe watery diarrhea (> 10 evacuations/day) with CDI negative; and Group D-severe watery diarrhea (> 10 evacuations/day) CDI positive. Clinical and laboratory data were analyzed for their correlation with CDI. A machine learning approach was used to determine predictors of diarrhea following stoma reversal.
RESULTS:  A total of 126 patients were selected, of whom 79 were assessed as Group A, 16 Group B, 25 Group C and 6 (4.8%) Group D. Univariable analysis documented that delayed stoma reversal correlated with CDI (Group A mean interval 44.6 weeks vs. Group D 68.4 weeks, p 0.01). The machine learning analysis confirmed the delay in stoma closure as a probability factor of presenting diarrhea; also, diarrhea probability was 80.5% in males, 77.8% in patients who underwent neoadjuvant therapy, and 63.9% in patients who underwent adjuvant therapy.
CONCLUSIONS:  Stoma reversal surgery can result in moderate rate of in-hospital CDI. Time-to stoma reversal is a crucial variable significantly related with this adverse outcome.