Robotic surgery, represented by the da Vinci™ system (hereafter da Vinci), has been adopted worldwide owing to its high precision and improved surgical outcomes. After key patents for da Vinci expired, the hinotori™ system (hereafter hinotori), Japan's first domestically developed surgical robot system, was introduced and received clinical approval in November 2022. Although hinotori is introduced as an alternative to da Vinci, its clinical performance in gastrointestinal surgery, particularly in colectomy, remains unclear. This study provided an overview of the surgical techniques for right colectomy using hinotori and retrospectively compared its short-term clinical outcomes with those of da Vinci, post-adjusting for background factors using propensity score matching (PSM).

Data from 88 consecutive patients who underwent robotic right colectomy at our institute between 2020 and 2024 were retrospectively reviewed. Patients were classified into the hinotori (n = 28) and da Vinci (n = 60) groups. PSM resulted in 26 patients being assigned to each group. Patient demographics, perioperative outcomes, pathological findings, and complication rates were analyzed and compared between the groups. Patients in both groups underwent standardized surgical procedures performed by the same surgeons using intracorporeal anastomosis. Role switching between the assistant and primary surgeon was required for some procedural steps owing to instrumentation limitations of hinotori.

No significant differences were observed in patient demographics between the propensity score-matched groups. Operative (277.5 vs. 242.5 min, p = 0.044) and console (210 vs. 184.5 min, p = 0.047) times were significantly longer in the hinotori group than in the da Vinci group. No significant differences in blood loss, Clavien-Dindo grade III or higher complications, or postoperative hospital stay were found between the groups. Both groups had comparable histopathological outcomes, including lymph node yield and resection margins.

Our findings suggest that perioperative outcomes in robotic right colectomy using hinotori are comparable to those of da Vinci.

Lymphadenectomy for rectal cancer is clearly defined by total mesorectal excision (TME). The analogous surgical strategy for the colon, the complete mesocolic excision (CME), follows the same principles of dissection in embryologically predefined planes.

This narrative review initially identified key issues related to lymphadenectomy of rectal and colon cancer. The subsequent search was based on PubMed and focused on meta-analyses. The endpoints for rectal cancer were the benefit of high tie versus low tie and the indications for lateral pelvic lymphadenectomy. For colon cancer the evidence for CME, for the longitudinal extent of resection, for the dissection of infrapyloric and gastroepiploic lymph nodes, for the number of lymph nodes and for the sentinel lymph node technique were used as endpoints.

An oncological benefit of the high tie cannot be derived from the current data. Lateral pelvic lymphadenectomy should only be selectively performed after chemoradiotherapy (CRT) in cases of remaining lymph nodes with suspected metastases. In most studies CME proved to be oncologically superior, especially in stage III. The longitudinal extent of resection should be at least 10 cm in both directions if the principles of CME are observed. Infrapyloric and gastroepiploic lymph node involvement is to be expected in 0.7-22% of cases, depending on patient selection, which justifies dissection, particularly in carcinomas of both flexure and the transverse colon. The minimum number of lymph nodes to be removed cannot be clearly derived from the available studies. Precisely performed CME and an optimal pathological work-up are important. The sentinel lymph node technique cannot currently be used as a criterion for limiting the extent of resection.

Both TME and CME are reliable standards for the lymphadenectomy in colorectal carcinomas. A lymphadenectomy that goes beyond this is reserved for selected cases and is partly the subject of currently ongoing studies.

Complete mesocolic excision (CME) is widely adopted for its assumed superior oncological outcome. However, it's unclear if all right-sided colon cancer patients benefit from CME. The aim of this systematic review is to investigate whether CME contributes to postoperative outcomes and to determine the surgical indications for CME.

We searched eligible articles about CME versus non-CME procedures for right-sided colon cancer in the OVID Medline, Embase, and Cochrane CENTRAL databases, and a meta-analysis was conducted.

Twenty-two articles and seven abstracts involving 8088 patients were included in this study. Among them, 3803 underwent CME and 4285 non-CME procedures. The analysis showed that CME was favoured for three-year disease-free survival (DFS) and overall survival (OS), for local, systemic, and total recurrence, and for hospital stay durations. However, increased vascular injury and longer surgery time were observed in CME. Regarding the three-year OS, the superiority of CME was observed only in Stage III. Additionally, no significant differences were observed between CME and non-CME groups regarding overall complications, 30-day readmission rates, reoperation, or postoperative mortality rates.

CME for right-sided colon cancer should be considered, particularly in Stage III patients, to contribute to improved oncological outcomes. However, careful attention must be paid to the increased risk of vascular injury.

We aimed to assess the efficacy and safety of low-pressure pneumoperitoneum (LPP) in minimally invasive colorectal surgery.

A PRISMA-compliant systematic review/meta-analysis was conducted, searching PubMed, Scopus, Google Scholar, and clinicaltrials.gov for randomized-controlled trials assessing outcomes of LPP vs standard-pressure pneumoperitoneum (SPP) in colorectal surgery. Efficacy outcomes [pain score in post-anesthesia care unit (PACU), pain score postoperative day 1 (POD1), operative time, and hospital stay] and safety outcomes (blood loss and postoperative complications) were analyzed. Risk of bias2 tool assessed bias risk. The certainty of evidence was graded using GRADE.

Four studies included 537 patients (male 59.8%). LPP was undertaken in 280 (52.1%) patients and associated with lower pain scores in PACU [weighted mean difference: -1.06, 95% confidence interval (CI): -1.65 to -0.47, P = 0.004, I 2  = 0%] and POD1 (weighted mean difference: -0.49, 95% CI: -0.91 to -0.07, P = 0.024, I 2  = 0%). Meta-regression showed that age [standard error (SE): 0.036, P < 0.001], male sex (SE: 0.006, P < 0.001), and operative time (SE: 0.002, P = 0.027) were significantly associated with increased complications with LPP. In addition, 5.9%-14.5% of surgeons using LLP requested pressure increases to equal the SPP group. The grade of evidence was high for pain score in PACU and on POD1 postoperative complications and major complications, and blood loss, moderate for operative time, low for intraoperative complications, and very low for length of stay.

LPP was associated with lower pain scores in PACU and on POD1 with similar operative times, length of stay, and safety profile compared with SPP in colorectal surgery. Although LPP was not associated with increased complications, older patients, males, patients undergoing laparoscopic surgery, and those with longer operative times may be at risk of increased complications.

Quality assurance in surgery has been one of the most important topics of debate among colorectal surgeons in the past decade. It has produced new surgical standards that led in part to the impressive oncological outcomes we see in many units today. Total mesorectal excision, complete mesocolic excision (CME), and the Japanese D3 lymphadenectomy are now benchmark techniques embraced by many surgeons and widely recommended by surgical societies. However, there are still ongoing discrepancies in outcomes largely based on surgeon performance. This is one of the main reasons why many countries have shifted colorectal cancer surgery only to high volume centers. Defining markers of surgical quality is thus a perquisite to ensure that standards and oncological outcomes are met at an institutional level. With the evolution of CME surgery, various quality markers have been described, mostly based on measurements on the surgical specimen and lymph node yield, while others have proposed radiological markers (i.e. arterial stumps) measured on postoperative scans as part of the routine cancer follow-up. There is no ideal marker; however, taken together and assembled into a new score or set of criteria may become a future point of reference for reporting outcomes of colorectal cancer surgery in research studies and defining subspecialization requirements both at an individual and hospital level.