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.

To explore the safety and feasibility of the modified approach for accessing the superior mesenteric artery (SMA) in total laparoscopic radical resection for right colon cancer.

This single-center retrospective study included 107 patients who underwent total laparoscopic radical resection of right colon cancer at The First Affiliated Hospital of Wannan Medical College between August 2022 and December 2023. 53 patients were in the modified SMA approach (modified group) and 54 patients were in the traditional SMA approach (control group). The control group and modified group underwent total laparoscopic radical resection of right colon cancer, and the following baseline and pathological characteristics of the two groups were compared: intraoperative condition, postoperative recovery, and postoperative complications. Our modified surgical method was to isolate the mesocolon using a cranial(the ligament of Treitz) -to- caudal(the pedicle of ileocolic) pathway and the orderly ligation of blood vessels in the SMA.

There was no statistically significant difference in the baseline characteristics or pathological data between the two groups. Compared with the traditional SMA approach, the modified SMA approach had a shorter surgical time(P < 0.001) and vascular dissection time (P < 0.001) and less intraoperative blood loss (P = 0.000). There was no statistically significant difference in the number of total harvested lymph nodes or positive harvested lymph nodes between the two groups of patients (P > 0.05); There was no statistically significant difference in postoperative hospital stay, time to first flatus, time to pull out drainage tube and drainage between the two groups of patients (P > 0.05), and there was no statistically significant difference in the incidence of complications between the two groups of patients (P > 0.05).

The modified SMA approach in totally laparoscopic radical resection for right colon cancer can shorten the surgical and vascular dissection time, reduce intraoperative bleeding and reduce the surgical difficulty and intraoperative risk of the SMA approach for right colon cancer. In clinical practice, its safety and feasibility are relatively high, and it is worth promoting.

The study was approved by the Ethics Committee of The First Affiliated Hospital of Wannan Medical College and registered with the China Clinical Trials Registry (ChiCTR2300075919, Date of Registration:2023-09-19- retrospective registration) http://www.chictr.org.cn/index.aspx .

The optimal extent of lymph node dissection in colon cancer surgery is specified in guidelines based on the results of past analyses. However, with advances in surgical techniques and multidisciplinary treatments, the clinical significance of dissecting each lymph node may change. In this study, we re-examined the optimal dissection range in each colon cancer localization. We retrospectively analyzed 788 cases of T1-T4 colon cancer who underwent radical resection between 2008 and 2018 at our hospital, and evaluated the Lymphadenectomy Index. No metastases to the main lymph node were found in T1 cases. In T2 cases, dissection effect to the main lymph node were observed in cases with tumors localized in the ascending colon and left side of the transverse colon. For tumors localized in the cecum, dissection was effective for lymph nodes in nodal station 213, in the right side of the transverse colon in station 211, in the descending colon in station 221, and in the sigmoid colon in station 231. These lymph nodes could have been considered out of scope for dissection if the Japanese guidelines were followed. In these cases, the extent of lymph node dissection should be carefully considered on a case-by-case basis.

A complete dissection around the superior mesenteric artery (SMA) with artery-first concept is crucial during pancreaticoduodenectomy for periampullary cancers. The left-posterior (LP) approach to the SMA may be effective during robot-assisted pancreaticoduodenectomy (RPD), but data on its technical feasibility and clinical outcomes are limited.

We retrospectively reviewed 83 RPD patients utilizing the LP approach, dividing them into early (n = 42) and late (n = 41) groups to assess procedural maturity. The LP approach was initiated at the first phase of resection to achieve circumferential SMA dissection from the left and posterior aspect and early vascular control through ligation of the inferior pancreaticoduodenal artery (IPDA). Postoperative short-term outcomes were compared between the two groups.

The late group demonstrated significantly shorter operative times (518 vs. 626 min; p < .01) and higher rates of IPDA ligation (90% vs. 71%; p = .03). The median blood loss in the late group was 50 mL (65 mL in the early group; p = .39). Lymph node retrieval number was 17 in both (p = .81), and R0 resection was achieved in all late group cases (96% in the early group; p = .35).

With experience from approximately 80 cases, the LP approach for RPD has enabled precise SMA dissection and early vascular control. A stable and super-magnified caudal view provided by robotic surgery is particularly advantageous for this approach.

In hepatic flexure and transverse colon cancer surgeries, mobilizing the right mesocolon and precisely dissecting the gastrocolic trunk of Henle (GTH) are crucial. Previous classifications of GTH tributaries do not guide radical right hemicolectomy due to post-procedural anatomical acquisition. This study analyzed vessel associations, including the middle colic vein (MCV) converging site, right colic artery (RCA) presence, and other GTH tributaries, using ultra-thin CT for reconstruction. GTH anatomy was categorized into medial and lateral types based on colic tributary convergence relative to ASPDV. Results showed the colic tributary joined GTH lateral to ASPDV in 45.81% and medial in 54.19% of cases. RCA presence was strongly linked to the lateral GTH type (56.76% vs. 43.24%, p < 0.001) when RCA was absent. MCV converged into the superior mesenteric vein (SMV) on the left side in 23.15% of cases, correlating with the right colic vein presence (odds ratio = 3.563, p = 0.007). This novel GTH variation pattern via high-level CT venography significantly correlates with RCA presence, aiding surgeons in anticipating GTH anatomy during laparoscopic radical right hemicolectomy.

Adjuvant chemotherapy (AC) for stage III disease is recognized as a standard treatment and is routinely performed in patients with colon cancer (CC). However, the recommendation for AC is mainly based on studies performed in past environments, where D3 lymphadenectomy was not routinely performed.

We retrospectively analyzed CC patients who underwent curative resection with D3 lymphadenectomy in Keio Surveillance Epidemiology and End Results (K-SEER) database. After patients were divided into AC and non-AC groups, propensity score matching (PSM) was performed to match the two groups.

After PSM, 84 patients were included in each group. There were no significant differences between the AC and non-AC groups in the 5-year cancer-specific survival (CSS; 88.01% vs. 81.46%, p = 0.295) and 5-year recurrence-free survival (RFS; 69.57 vs. 70.08%, p = 0.820), respectively. In the subgroup analysis, AC improved both the CSS [hazard ratio (HR)0.273; 95% confidence interval (CI) 0.094-0.797, p = 0.017] and RFS (HR 0.376; 95% CI 0.174-0.806, p = 0.012) only for tumors with N2 disease compared to non-AC.

The current indications for AC in patients with CC after D3 lymphadenectomy should be reconsidered. It is possible that AC is appropriate only for stage III CC patients with N2 disease.

The incidence of colorectal cancer (CRC) has increased in recent decades, and ranks fourth among males and third among females in China. Surgical resection remains the most important treatment modality for curative intent in CRC. Several studies found that surgeon volumes and specialization appeared to be associated with improved overall survival (OS). Moreover, numerous reports have suggested that specialization and minimally invasive surgery have gained increased popularity in CRC surgery. However, few studies have specifically examined the role and long-term survival of all stage CRC in a real-world study.

To evaluate the effect of surgeon specialization on survival changes and minimally invasive surgery utilization in a real world study.

A retrospective analysis on the association between surgeon specialization and OS between 2008 and 2013 in Zhongshan Hospital CRC database was performed. Standard demographic, clinicopathologic, surgical and follow-up data were obtained from the CRC database. Surgeon specialty was categorized as colorectal surgeon (CS) and general surgeon (GS). CRC patients who underwent primary surgical resection were enrolled.

A total of 5141 CRC patients who underwent primary surgical resection between 2008 and 2013 were evaluated, 1748 (34.0%) of these by CS. The percentage of minimally invasive procedures in the CS group showed an increasing trend. There was no benefit associated with surgeon specialization for stage I, II and IV patients. Surgeon specialization exhibited a significant association with OS solely among stage III patients, with 5-year OS rates of 76% and 67% for the CS and GS groups, respectively (P < 0.01). Further analyses found that surgeon specialization was significantly associated with survival only in stage III rectal patients, and the 5-year OS rate in the CS group and GS group was 80% and 67%, respectively (P < 0.01).

Surgeon specialization is associated with improved OS after primary surgery in stage III rectal patients. An appropriate surgical technique, perioperative program and adjuvant therapy may contribute to survival benefit in these patients.

Pivotal articles that had been published between 2022 and 2023 on surgical and perioperative adjuvant treatments for locally advanced colorectal cancer (CRC) were reviewed. This review focuses on new evidence in the following areas: optimization of surgical procedures for colon cancer, including the optimal length of bowel resection and use of the no-touch isolation technique; minimally invasive surgery for rectal cancer, such as laparoscopic transanal total mesorectal excision and robotic surgery; neoadjuvant treatments for rectal cancer, including total neoadjuvant therapy; neoadjuvant chemotherapy for colon cancer; and postoperative adjuvant chemotherapy for Stage II and III colon cancer. Although the current understanding may not enable perfect decision-making for patients and medical professionals, ongoing advancements are expected to result in more effective personalized treatment plans, ultimately improving the prognosis and quality of life of patients.

Although laparoscopy has some limitations related to tumor size or location along the colon, it has been demonstrated that the oncological results are just as good as for open surgery. One can also add to the benefits faster recovery and start of chemotherapy, with lower rates of complications. Our study aimed to compare open surgery to laparoscopy for non-complicated colon tumors operated in an average case-load center and appreciate its feasibility with regards to the T stage, lymph node yield and conversions. The study is retrospective and expanded over four years (January 2020-January 2024). One hundred sixty-two patients were included in the study. We observed that female patients were frequently operated through laparoscopy (p=0.003). T1 and T2 tumors represented the majority of the tumors in the laparoscopy group (p=0.004). No statistical difference existed in terms of lymph node yield. Laparoscopy was avoided for tumors of the splenic angle (p=0.006). Concluding our results, minimally invasive surgery for non-complicated colon cancer is non-inferior to open surgery. Considerable expertise is required to take on more complex cases such as difficult-to-access tumors or large, invasive cancers. It can and should be offered to patients as an alternative to open surgery.

Ex vivo tissue morphometric (TM) measurements have been proposed as a quality marker for colorectal cancer (CRC) surgery. However, their survival associations require clarification. This study aimed to evaluate the feasibility of capturing TM measurements based on ex vivo fresh specimen images and explore the association between these TM measurements and survival outcomes.

A prospective cohort study at Concord Hospital, Sydney was conducted with Stage I to III CRC patients (2009-2019) who underwent an anterior resection (AR) or right hemicolectomy (RH). Using high-resolution digital photographs of fresh CRC specimens, ex vivo tissue morphometric (TM) measurements-resected mesentery area (TM A), distances from high vascular tie to tumour (TM B) and bowel wall (TM C), and bowel length (TM D)-were recorded using Image J. Overall survival (OS) and disease-free survival (DFS) estimates and their associations to clinicopathological variables were investigated with Kaplan-Meier and Cox regression analyses. Linear regression models tested association between TM measurements and lymph node (LN) yield.

Of the 1,425 patients who underwent CRC surgery, TM measurements were performed on 312 patients, with an average age of 69.4 years (SD 12.3), of whom 52.9% were male. The majority had an AR (57.8%). Among AR patients, a 5-year OS rate of 77.4% and a DFS rate of 70.1% were observed, with TM measurements bearing no relationship to survival outcomes. Similarly, RH patients exhibited a 5-year OS rate of 67.2% and a DFS rate of 63.1%, with TM measurements again showing no association with survival. Only TM D (P = 0.02) measurements were associated with the number of LNs examined.

This study successfully demonstrates the feasibility of measuring TM measurements on photographs of ex vivo fresh specimens following CRC surgery. The lack of association with survival outcomes questions the utility of TM measurements as a quality metric of CRC surgery.

To prospectively determine the influence of variations of surgical radicality and surgical quality on long-term outcome in patients with stage I-III colon cancer.

From a prospective multicenter cohort study including 1040 patients undergoing surgery for colorectal cancer from 09/2001 to 06/2005 in nine Swiss and one German hospital, 423 patients with stage I-III colon cancer were selected and analyzed. Surgeons and pathologists filled in standardized forms prospectively assessing items of oncosurgical radicality and quality. Patients had standardized follow-up according to national guidelines.

Follow-up was median 6.2 years (range 0.3-10.4) showing a 5-year disease-free survival/overall survival of 83 %/87 % in stage I (n = 85), 69 %/77 % in stage II (n = 187), and 53 %/61 % in stage III (n = 151) colon cancer. Despite remarkable variations of oncosurgical radicality and quality, the multivariate model revealed that mainly quality items correlated significantly with disease-free survival (surgical tumor lesion HR 2.12, p = 0.036, perioperative blood transfusion HR 1.67, p = 0.018, emergency resection HR 1.74, p = 0.035) and overall survival (early venous ligation HR 0.66, p = 0.023, surgical tumor lesion HR 2.28, p = 0.027, perioperative blood transfusion HR1.79, p = 0.010, emergency resection HR 1.88, p = 0.026), while radicality parameters (length of specimen, distance of the tumor to nearest bowel resection site, number of lymph nodes, height of resected mesocolon and of central vascular dissection) did not.

Surgical quality seems to have a stronger impact on oncologic long-term outcome in stage I - III colon cancer than surgical radicality.

Colon cancer is a global health concern, ranking fifth in both new diagnoses and deaths among tumors worldwide. Surgical intervention remains the primary treatment for localized cases, with a historical evolution marked by a focus on short-term outcomes. While Japan pioneered radical tumor removal with a systematic categorization of lymph nodes (D1, D2, D3), the dissemination of Japanese practices to the West was delayed until 90th of last century. Discrepancies between Japanese D3 dissection and the CME with CVL principle persist, with variations in longitudinal margins and recommended procedures. Non-randomized trials indicate the superiority of D3 over D2, but a consensus is lacking.

This prospective, international, multicenter, randomized controlled trial employs a two-arm, parallel-group, open-label design to rigorously compare the 5-year overall survival outcomes between D2 and D3 lymph node dissection in stage II-III right colon cancer. Building on prior studies, the trial aims to address existing knowledge gaps and provide a comprehensive evaluation of the outcomes associated with D3 dissection. The study population comprises patients with right colon cancer, ensuring a focused investigation into the specific context of this disease. The trial design emphasizes its global scope and collaboration across multiple centers, enhancing the generalizability of the findings.

This study's primary objective is to elucidate the potential superiority in 5-year overall survival benefits of D3 lymph node dissection compared to the conventional D2 approach in patients with stage II-III right colon cancer. By examining this specific subset of patients, the research aims to contribute valuable insights into optimizing surgical strategies for improved long-term outcomes. The trial's international and multicenter nature enhances its applicability across diverse populations. The outcomes of this study may inform future guidelines and contribute to the ongoing discourse surrounding the standardization of colon cancer surgery, particularly in the context of right colon cancer.

ClinicalTrials.gov NCT03200834. Registered on June 27, 2017.

Complete mesocolic excision and central vascular ligation with D3 lymphadenectomy are important surgical principles for improving oncological outcomes in colon cancer. The cranial-first approach is a colonic mobilization-first approach to radical right hemicolectomy, which has several advantages, including early feasibility assessment, safe dissection from surrounding organs, preestablished inferior margin of lymph node dissection, and revelation of the tangible anatomy of the tributaries of the gastrocolic trunk. This video demonstrates the cranial-first approach to radical right hemicolectomy in a 66-year-old man with locally advanced cecal cancer.

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.

Quality of surgery has recently become an essential topic in the prognosis of colon cancer. Complete mesocolic excision for colon cancer has recently gained popularity with high-quality surgery. Patient specimens after complete mesocolic excision with central vessel ligation procedures have an integrity of the mesocolon and the yield of three fields of lymph node harvest. We apply the glacial acid, absolute ethanol, water, and formaldehyde solution to each specimen based on the Japanese classification of lymph node groups and station numbers. We aim to identify the distribution and status of lymph node metastasis according to each tumor site and some pathological characteristics related to this disease.

A prospective cohort study was performed on 45 laparoscopic complete mesocolic excision surgery patients.

2791 lymph nodes were harvested after complete mesocolic excision surgery. The average number was 62.0 ± 22.3 nodes. The mean tumor size (in the largest dimension) was 4.2 ± 1.8 cm. The average length of the resected bowel segments was 29.1 ± 7.7 cm. There are 63 (2.3%) node metastases in 2791 lymph nodes, in which 17/45 (37.8%) patients had pN(+). The minimum positive node size was 1 mm. The positive pericolic lymph nodes (station 1) accounted for the highest rate, with 53 nodes (1.9%). The number of lymph nodes in young age ⩽60 is more significant than in older. The results were similar, with a more significant node retrieval in the group with a tumor size >4.5 cm and specimen length >25 cm. The number of lymph nodes in lower tumor invasive (pT1,3) was smaller than pT4. Our research shows that the cecum, ascending, and descending colon had greater nodes than others, with a mean number of 78.6, 74.2, and 71.3, respectively.

The metastasis and harvested lymph nodes accounted for the highest rate of colon cancer in station 1 and the lowest rate in station 3. The number of retrieved lymph nodes was significantly associated with tumor location, size, specimen length, and patient age.

Debate exists concerning the impact of complete mesocolic excision (CME) on long-term oncological outcomes. The aim of this review was to condense the updated literature and assess the effect of CME on long-term survival after right colectomy for cancer.

PubMed, MEDLINE, Scopus, and Web of Science were searched through July 2023. The included studies evaluated the effect of CME on survival. The primary outcome was long-term overall survival. Restricted mean survival time difference (RMSTD), hazard ratio (HR), and 95% confidence intervals (CI) were used as pooled effect size measures. GRADE methodology was used to summarize the certainty of evidence.

Ten studies (3665 patients) were included. Overall, 1443 (39.4%) underwent CME. The RMSTD analysis shows that at 60-month follow-up, stage I-III CME patients lived 2.5 months (95% CI 1.1-4.1) more on average compared with noCME patients. Similarly, stage III patients that underwent CME lived longer compared to noCME patients at 55-month follow-up (6.1 months; 95% CI 3.4-8.5). The time-dependent HRs analysis for CME vs. noCME (stage I-III disease) shows a higher mortality hazard in patients with noCME at 6 months (HR 0.46, 95% CI 0.29-0.71), 12 months (HR 0.57, 95% CI 0.43-0.73), and 24 months (HR 0.73, 95% CI 0.57-0.92) up to 27 months.

This study suggests that CME is associated with unclear OS benefit in stage I-III disease. Caution is recommended to avoid overestimation of the effect of CME in stage III disease since the marginal benefit of a more extended resection may have been influenced by tumor biology/molecular profile and multimodal adjuvant treatments.

The modified complete mesocolic excision (mCME) procedure for right-sided colon cancer is a tailored approach based on the original complete mesocolic excision (CME) methodology. Limited studies evaluated the safety and feasibility of laparoscopic mCME using objective surgical quality assessments in patients with right colon cancer. The objectives of the PIONEER study were to evaluate oncologic outcomes after laparoscopic mCME and to identify optimal clinically relevant endpoints and values for standardizing laparoscopic right colon cancer surgery based on short-term outcomes of procedures performed by expert laparoscopic surgeons.

This is an ongoing prospective, multi-institutional, single-arm study conducted at five tertiary colorectal cancer centers in South Korea. Study registrants included 250 patients scheduled for laparoscopic mCME with right-sided colon adenocarcinoma (from the appendix to the proximal half of the transverse colon). The primary endpoint was 3-year disease-free survival. Secondary outcomes included 3-year overall survival, incidence of morbidity in the first 4 weeks postoperatively, completeness of mCME, central radicality, and distribution of metastatic lymph nodes. Survival data will be available after the final follow-up date (June 2024).

The postoperative complication rate was 12.9%, with a major complication rate of 2.7%. In 87% of patients, central radicality was achieved with dissection at or beyond the level of complete exposure of the superior mesenteric vein. Mesocolic plane resection with an intact mesocolon was achieved in 75.9% of patients, as assessed through photographs. Metastatic lymph node distribution varied by tumor location and extent. Seven optimal clinically relevant endpoints and values were identified based on the analysis of complications in low-risk patients.

Laparoscopic mCME for right-sided colon cancer produced favorable short-term postoperative outcomes. The identified optimal clinically relevant endpoints and values can serve as a reference for evaluating surgical performance of this procedure.

The aim of this study was to determine the genuine prognostic relevance of primary tumor sidedness (PTS) in patients with early-stage colorectal cancer (CRC).

The prognostic relevance of PTS in early-stage CRC remains a topic of debate. Several large epidemiological studies investigated survival only and did not consider the risk of recurrence so far.

Patients with stage II/III adenocarcinoma of the colon and upper rectum from 4 randomized controlled trials were analyzed. Survival outcomes were compared according to the tumor location: right-sided (cecum to transverse colon) or left-sided (descending colon to upper rectum).

A total of 4113 patients were divided into a right-sided group (N=1349) and a left-sided group (N=2764). Relapse-free survival after primary surgery was not associated with PTS in all patients and each stage [hazard ratio (HR) adjusted =1.024 (95% CI: 0.886-1.183) in all patients; 1.327 (0.852-2.067) in stage II; and 0.990 (0.850-1.154) in stage III]. Also, overall survival after primary surgery was not associated with PTS in all patients and each stage [HR adjusted =0.879 (95% CI: 0.726-1.064) in all patients; 1.517 (0.738-3.115) in stage II; and 0.840 (0.689-1.024) in stage III]. In total, 795 patients (right-sided, N=257; left-sided, N=538) developed recurrence after primary surgery. PTS was significantly associated with overall survival after recurrence (HR adjusted =0.773, 95% CI: 0.627-0.954).

PTS had no impact on the risk of recurrence for stage II/III CRC. Treatment stratification based on PTS is unnecessary for early-stage CRC.

Competing-risk analysis was used to accurately assess prognostic factors for cancer-specific death in patients with adenocarcinoma of transverse colon (ATC), and the results were compared with those from a conventional Cox regression analysis.

Patients diagnosed with ATC between 2000 and 2019 were selected from the Surveillance, Epidemiology, and End Results database. The crude mortality rates of patients with ATC were calculated and their differences were tested using the Gray's test, respectively. In performing multivariate analysis, the Cox regression model and the subdistribution hazard function (SD) in competing risk analysis were utilized, respectively.

This study included 21,477 eligible patients. The SD model indicated that age, etc. are actual independent prognostic factors. In contrast to previous recognition, the results of the Cox regression showed false-positives for sex and Carcinoembryonic antigen, and underestimated point-estimates in the stage and American Joint Committee on Cancer stage due to competing events. A detailed comparison of treatment revealed that the larger surgical scopes were prognostic risk factors compared with the smaller scope of local tumor excision, partial colectomy, or segmental resection. Patients treated with external proton beam radiotherapy had an increased risk compared with those with no radiotherapy and internal radiotherapy.

After comparing the results of the two methods and mitigating the significant bias introduced by Cox regression, we found independent factors that really affect the prognosis of ATC. On the other hand, in terms of ATC, a larger surgical scope and external proton beam radiotherapy may not improve the long-term survival of patients. Therefore, when faced with ATC patients, these differences should be noted and treated differently from common colorectal cancer patients. Thus, clinicians are able to give more targeted treatment plans and prognostic assessments.

Positive pathologic lymph nodes in colorectal cancer represent an important prognostic indicator. Whether lymph node distribution or the number of metastatic nodes is more strongly associated with survival prediction remains controversial.

Among 3449 colorectal cancer surgeries performed at Nagasaki University Hospital and five affiliated institutions from April 2016 to March 2022, we investigated 604 patients who underwent laparoscopic radical resection and were diagnosed with pathological stage III cancer. Patients were divided into two groups according to whether they had central vessel metastasis (LND3 group, n=42) or not (LND1/2 group, n=562). After adjusting for background factors using propensity score matching, the LND3 group included 42 patients and the LND1/2 group included 40 patients. Patient background characteristics and prognosis were compared between these two groups.

Before matching, frequencies of right-side colon cancer (64.3% vs 38.1%, p=0.001), multivisceral resection (11.9% vs 4.4%, p=0.039), clinical N2 status (40.5% vs 22.6%, p=0.032), and pathological N2 (73.8% vs 22.6%, p<0.001) were all greater, and the number of lymph nodes retrieved was higher (24 vs 19, p=0.042) in the LND3 group. After matching, no differences in any clinical factors were evident between groups. Five-year RFS (44.8% vs 77.1%, p=0.004) and OS (43.1% vs 83.2%, p<0.001) were worse in the LND3 group. Adjuvant chemotherapy improved RFS (adjuvant chemotherapy (+) vs adjuvant chemotherapy (-): 62.1% vs 27.7%, p=0.047) in the LND3 group.

LND3-positive patients show poorer prognosis than LND1/2 patients and should be treated with an appropriate perioperative treatment strategy.

To compare the oncological survival outcomes of partial colectomy (PC) and hemicolectomy (HC) in patients with stage II colon cancer. A total of 18,795 patients with stage II colon cancer who underwent hemicolectomy (n = 12,022) or partial colectomy (n = 6773) from 2010 to 2019 were included in the the Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) were compared between the two groups, and the threshold of harvested lymph nodes was determined. The results showed that age, gender, race, tumor site, scope of regional lymph nodes, postoperative chemotherapy, postoperative radiotherapy, harvested lymph nodes, and tumor size were significantly different between the PC and HC groups (all P < 0.05). The OS rate was slightly lower in hemicolectomy patients than in partial colectomy patients (69.9% vs. 74.5%, respectively, P < 0.001), but CSS was similar between the two groups (87.9% vs. 88.1%, respectively, P = 0.32). After propensity score matching (PSM) was performed, the OS and CSS rates in the two groups were significantly different (CSS 84.3% vs. 88.0%, P < 0.001; OS 62.2% vs. 72.5%, P < 0.001). The survminer R package determined that the optimum threshold for the harvested lymph node count in stage II colon cancer patients was 16. CSS was significantly different between patients with ≥ 12 lymph nodes harvested and patients with ≥ 16 lymph nodes harvested (P = 0.043). Univariate and multivariate Cox regression and survival analyses of stage II colon cancer patients showed that the survival benefit of stage II colon cancer patients receiving partial colectomy was superior to that of patients receiving hemicolectomy. Partial colectomy has significant oncological benefits over hemicolectomy in the treatment of stage II colon cancer patients, even in the case of pT4b or tumor deposits. Removal of 16 lymph nodes during colectomy for stage II colon cancer correlated with improved survival, and this threshold was more effective than the standard threshold of 12 lymph nodes in distinguishing between patients with good and poor prognoses.

We evaluated the risk of metachronous colorectal cancer (mCRC) and explored the optimal extent of colectomy in patients with Lynch syndrome (LS) and first colon cancer (fCC) in Japan, where the extent of colectomy for colon cancer (CC) is shorter than that in Western countries.

The clinicopathologic and survival data of patients with LS who developed CC were collected from a nationwide database and analyzed retrospectively. The cumulative incidence of mCRC after actual segmental colectomy was compared with that of mCRC when more extensive colectomy was assumed.

There were 142 eligible patients (65 female). The median age at fCC surgery was 46.5 (range: 14-80) years. The cumulative incidence of 5-, 10-, and 20-year mCRC rate was 13.4%, 20.8%, and 53.6%, respectively. The incidence was higher in the left-sided group (splenic flexure to rectosigmoid colon, n = 54) than in the right-sided group (cecum to transvers colon, n = 88) (66.3% vs. 45.3% in 20 years, P < 0.01). Assuming that all patients would have undergone hemicolectomy or total colectomy, the estimated mCRC risk was 41.5% and 9.4% (P < 0.01, vs. actual procedures), respectively. The 20-year overall survival rate of all the patients was 83.3% without difference by fCC sidedness (P = 0.38).

To reduce the incidence of mCRC, patients with genetically diagnosed LS and fCC, preferentially located in the left-sided colon, may need to undergo more extended colectomy than that usually performed in Japan. However, such extended colectomy should be counterbalanced with favorable overall survival and actual risk of mCRC development.

Recent advancements in endoscopic procedures have resulted in a growing diagnosis of early colorectal cancer (CRC) cases, where classical en bloc lymph node (LN) dissection is not performed and treatment is terminated with the removal of the main cancer lesion by endoscopy without pathologic LN staging. Although many studies report noninferior outcomes of endoscopic resection in comparison to surgical resection, a cautious approach to completing treatment with endoscopic resection alone is recommended because LN metastases may be present even in early-stage CRC. In most countries, including the United States, Europe, and South Korea, the guidelines for additional surgery after endoscopic resection are very similar. If LN metastasis is suspected, even in T1 stage or lower lesions, further surgery is an essential treatment modality, but confirmation of the presence of LN metastasis is perhaps the most difficult part of this process. Another paradoxical recent trend is the expansion of more extensive and complete surgical lymphadenectomy for CRC. The success rate of surgery has improved dramatically over the past decade with the introduction of surgical devices and minimally invasive surgery, and the associated risks have been significantly reduced. While the burden of surgery on patients is understandable, the indications for surgery in early colon cancer need to be carefully reviewed to improve cure rates. In this process, we believe that an integrated decision-making process with surgeons, radiologists, and pathologists, in addition to the opinions of endoscopists, will be an important process to improve the cure rate.

The lymph node metastasis rate in right-sided colon cancer is unknown, and the optimal central vascular ligation level remains controversial. We aimed to determine the lymph node metastasis rate and short-term results of radical surgery with extended lymph node dissection in right-sided colon cancer.

This prospective multicenter observational study included patients with stage II/III right-sided colon cancer from five cancer hospitals. The metastasis rate of each node station was analyzed according to tumor location and main feeding artery.

Between April 2018 and August 2021, 208 patients underwent dissection around the superior mesenteric artery (SMA) and vein (SMV). In transverse colon cancer, 7.5% and 2.5% of metastases occurred around the SMV and SMA at the root of the middle colic artery (MCA), respectively; 6.7% and 6.7% at the root of the right colic artery. In caecal cancer, 1.9% of metastases occurred around the SMV and 1.9% around the SMA. In ascending colon cancer, the rate was 1.1% around the SMV. Of the tumors, 17% fed mainly by the ileocolic artery had node metastases along the middle or right colic artery, as did 66.7% fed mainly by the right colic artery and 41.2% fed by the MCA (p = 0.01). Postoperative complications occurred in 42 patients (20.2%).

Routine prophylactic extended lymphadenectomy around the SMA might not be necessary in caecum and ascending colon cancer. Dissection around the SMA may be necessary in cases of transverse colon cancer or when the feeding artery is the MCA.

Adequate lymph node (LN) excision is imperative for pathologic staging and determination of adjuvant treatment.

he 2004-2017 National Cancer Database (NCDB) was queried for curative colon cancer resections. Tumors were categorized by location: left, right, and transverse colon cancers. Adequate (12-20 LNs) vs. inadequate (<12 LNs) lymphadenectomy was examined and sub-analysis of <12 LNs, 12-20 LNs or >20 LNs. Primary outcome was predictors of inadequate lymph node retrieval.

Of 101,551 patients, 11.2% (11,439) had inadequate lymphadenectomy. The inadequate lymphadenectomy rate steadily decreased. On multivariable analysis, inadequate LN retrieval was associated with transverse (OR 1.49, CI [1.30-1.71]) and left colon cancers (OR 2.66, CI [2.42-2.93], whereas income >$63,333 had decreased likelihood of inadequate LN retrieval (OR 0.68, CI[0.56-0.82].

We are making the grade as NCDB data demonstrates a steady decrease in inadequate lymphadenectomy (2004-2017). There remain socioeconomic risk factors for inadequate lymphadenectomy that need to be addressed.

Colon cancer is a common disease internationally. Outcomes have not improved to the same degree as in rectal cancer, where the focus on total mesorectal excision and pathological feedback has significantly contributed to improved survival and reduced local recurrence. Colon cancer surgery shows significant variation around the world, with differences in mesocolic integrity, height of the vascular ligation and length of the bowel resected. This leads to variation in well-recognised quality measures like lymph node yield. Pathologists are able to assess all of these variables and are ideally placed to provide feedback to surgeons and the wider multidisciplinary team to improve surgical quality over time. With a move towards complete mesocolic excision with central vascular ligation to remove the primary tumour and all mechanisms of spread within an intact package, pathological feedback will be central to improving outcomes for patients with operable colon cancer. This review focusses on the key quality measures and the evidence that underpins them.

The splenic flexure has variable vascular anatomy, and the details of the venous forms are not known. In this study, we report the flow pattern of the splenic flexure vein (SFV) and the positional relationship between the SFV and arteries such as the accessory middle colic artery (AMCA).

This was a single-centre study using preoperative enhanced CT colonography images of 600 colorectal surgery patients. CT images were reconstructed into 3D angiography. SFV was defined as a vein flowing centrally from the marginal vein of the splenic flexure visible on CT. AMCA was defined as the artery feeding the left side of the transverse colon, separate from the left branch of the middle colic artery.

The SFV returned to the inferior mesenteric vein (IMV) in 494 cases (82.3%), the superior mesenteric vein in 51 cases (8.5%) and the splenic vein in seven cases (1.2%). The AMCA was present in 244 cases (40.7%). The AMCA branched from the superior mesenteric artery or its branches in 227 cases (93.0% of cases with existing AMCA). In the 552 cases in which the SFV returned to the IMV, superior mesenteric vein or splenic vein, the left colic artery was the most frequent artery accompanying the SFV (42.2%), followed by the AMCA (38.1%) and the left branch of the middle colic artery (14.3%).

The most common flow pattern of the vein in the splenic flexure is from the SFV to IMV. The SFV is frequently accompanied by the left colic artery or AMCA.

The management of splenic flexure cancers (SFCs) in the era of complete mesocolic excision (CME) and central vascular ligation (CVL) is challenging because of its variable lymphatic drainage. This study aimed to compare survival outcomes for SFCs and non-SFCs, and better understand the clinicopathological characteristics which may define a distinct SFC phenotype.

An observational cohort study at Concord Hospital, Sydney was conducted with patients who underwent resection for colon adenocarcinoma (1995-2019). Clinicopathological data were extracted from a prospective database. Overall survival (OS) and disease-free survival (DFS) estimates and their associations to clinicopathological variables were investigated with Kaplan-Meier and Cox regression analyses.

Of 2149 patients with colon cancer, 129 (6%) had an SFC. The overall 5-year OS and DFS rates were 63.6% (95% CI 62.5-64.7) and 59.4% (95% CI 58.3-60.5), respectively. SFCs were not associated with OS (P = 0.6) or DFS (P = 0.5). SFCs were more likely to present urgently (P < 0.001) with obstruction (P < 0.001) or perforation (P = 0.03), and more likely to require an open operation (P < 0.001). These characteristics were associated with poorer survival outcomes. No differences were noted between SFCs and non-SFCs with respect to tumour stage (P = 0.3).

SFCs have a distinct phenotype, the individual characteristics of which are associated with poorer survival. However, the survivals of SFCs and non-SFCs are similar, possibly because the most important determinant of outcome, tumour stage, is no different between the groups. This may have implications for the surgical approach to SFCs with respect to standardization of CME and CVL surgery for these cancers.

Complete mesocolic excision (CME) with central vascular ligation (CVL) involves sharp dissection through the embryological planes. However, it may be associated with high mortalities and morbidities especially in colorectal emergencies. This study aimed to investigate the outcomes of CME with CVL in complicated colorectal cancers (CRCs). This was a retrospective study of emergency CRC resection in a tertiary center between March 2016 and November 2018. A total of 46 patients, with a mean age of 51 years, underwent an emergency colectomy for cancer (males, 26 [56.5%]; females, 20 [43.5%]). CME with CVL was performed for all patients. The mean operative time and blood loss were 188 min and 397 mL, respectively. Only five (10.8%) patients presented with burst abdomen, whereas only three (6.5%) presented with anastomotic leakage. The mean length of vascular tie was 8.7 cm, and the mean number of harvested lymph nodes (LNs) was 21.2. Emergency CME with CVL is a safe and feasible technique when performed by a colorectal surgeon and will result in obtaining a superior specimen with a large number of LNs.

To evaluate the prognostic impact and describe suturing tools of mesenteric closure after laparoscopic right hemicolectomy (LRH).

PubMed, Embase, Cochrane library, Web of Science, and Scopus databases, were searched and publications relating to mesenteric closure data and tools were extracted. Search terms: "Mesenteric Defects" and "Mesenteric Closure" were used, and manual searches of eligible articles from literature reference lists performed.

A total of 7 publications were identified. 5 focused on prognostic impact and 4 referred to tools for mesenteric closure, two of which concerned both prognostic data and tools. All studies related to prognostic impact were single center with "low" modified GRADE quality. A high degree of heterogeneous was found.

The evidence from current research does not support routine closure of mesenteric defects. Use of a polymer ligation clip has produced favorable results in a small sample size trial and further investigation is merited. A large randomized controlled trial is still warranted.

The purpose of this study was to compare the "caudal to cranial" (CC) versus "medial to lateral" (ML) approach for laparoscopic right hemicolectomy. Pertinent data from all patients with stage II and III between January 2015 and August 2017 were entered into a retrospective database. A total of 175 patients underwent the ML (N = 109) or CC approach (N = 66). Patient characteristics were equivalent between groups. The CC group showed a shorter surgical time 170.00 (145.00, 210.00) vs. (206.50 (178.75, 226.25) min) than the ML group (p < 0.001). The time to oral intake was shorter in the CC group than in the ML group ((3.00 (1.00, 4.00) vs. 3.00 (2.00, 5.00) days; p = 0.007). For the total harvested lymph nodes, there was no statistical significance between the CC group 16.50 (14.00, 21.25) and the ML group 18.00 (15.00, 22.00) (p = 0.327), and no difference was found in the positive harvested lymph nodes (0 (0, 2.00) vs. 0 (0, 1.50); p = 0.753). Meanwhile, no differences were found in other perioperative or pathological outcomes, including blood loss and complications. For 5-year prognosis, overall survival rates were 75.76% in the CC group and 82.57% in the ML group (HR 0.654, 95% CI 0.336-1.273, p = 0.207); disease-free survival rates were 80.30% in the CC group and 85.32% in the ML group (HR 0.683, 95% CI 0.328-1.422, p = 0.305). Both approaches were safe and feasible and resulted in excellent survival. The CC approach was beneficial in terms of the surgical time and time to oral intake.

Complete mesocolic excision (CME) or D3 lymphadenectomy led to survival benefits for locally advanced right colon cancer, but with vague definitions in anatomy and debated surgical hazard in clinic. Aiming to achieve a precise definition of it in anatomy, we proposed laparoscopic right hemicolectomy (D3 + CME) as a novel procedure for colon cancer. However, the surgical and oncological results of this procedure in clinic were uncertain.

We performed a cohort study involving prospective data collected from a single-center in China. Data from all patients who underwent right hemicolectomy between January 2014 and December 2018 were included. We compared the surgical and oncological outcomes between D3 + CME and conventional CME.

After implementation of exclusion criteria, a total of 442 patients were included. D3 + CME group performed better in lymph nodes harvested (25.0 [17.0, 33.8] vs. 18.0 [14.0, 25.0], P < 0.001) and the proportion of intraoperative blood loss ≥ 50 mL (31.7% vs. 51.8%, P < 0.001); no significant difference was observed in the complication rates between two groups. Kaplan-Meier analysis demonstrated that a better cumulative 5-year disease-free survival (91.3% vs. 82.2%, P = 0.026) and a better cumulative 5-year overall survival (95.2% vs. 86.1%, P = 0.012) were obtained in the D3 + CME group. Multivariate COX regression revealed that D3 + CME was an independent protective factor for disease-free survival (P = 0.026).

D3 + CME could improve surgical and oncological outcomes simultaneously for right colon cancer compared to conventional CME. Large-scale randomized controlled trials were further required to confirm this conclusion, if possible.

Near-infrared fluorescence (NIRF) image-guided surgery is a useful tool that can help reduce perioperative complications and improve tissue recognition. Indocyanine green (ICG) dye is the most frequently used in clinical studies. ICG NIRF imaging has been used for lymph node identification. However, there are still many challenges in lymph node identification by ICG. There is increasing evidence that methylene blue (MB), another clinically applicable fluorescent dye, can also be useful in the intraoperative fluorescence-guided identification of structures and tissues. We hypothesized that MB NIRF imaging could be used for lymph node identification. The aim of this study was to evaluate the feasibility of intraoperative lymph node fluorescence detection using intravenously (IV) administered MB and compare it to ICG via a camera that has two dedicated near-infrared (NIR) channels. Three pigs were used in this study. ICG (0.2 mg/kg) was administered via a peripheral venous catheter followed by immediate administration of MB (0.25 mg/kg). NIRF images were acquired as video recordings at different time points (every 10 min) over an hour using the QUEST SPECTRUM^® 3 system (Quest Medical Imaging, Middenmeer, The Netherlands), which has two dedicated NIR channels for simultaneous intraoperative fluorescence guidance. The 800 nm channel was used to capture ICG fluorescence and the 700 nm channel was used for MB. The target (lymph nodes and small bowel) and the background (vessels-free field of the mesentery) were highlighted as the regions of interest (ROIs), and corresponding fluorescence intensities (FI) from these ROIs were measured. The target-to-background ratio (TBR) was then computed as the mean FI of the target minus the mean FI of the background divided by the mean FI of the background. In all included animals, a clear identification of lymph nodes was achieved at all time points. The mean TBR of ICG in lymph nodes and small bowel was 4.57 ± 1.00 and 4.37 ± 1.70, respectively for the overall experimental time. Regarding MB, the mean TBR in lymph nodes and small bowel was 4.60 ± 0.92 and 3.27 ± 0.62, respectively. The Mann-Whitney U test of the lymph node TBR/small bowel TBR showed that the TBR ratio of MB was statistically significantly higher than ICG. The fluorescence optical imaging technology used allows for double-wavelength assessment. This feasibility study proves that lymph nodes can be discriminated using two different fluorophores (MB and ICG) with different wavelengths. The results suggest that MB has a promising potential to be used to detect lymphatic tissue during image-guided surgery. Further preclinical trials are needed before clinical translation.

There are no standardised criteria for the 'regional' pericolic node in colon cancer, which represents a major cause of the international uncertainty regarding the optimal bowel resection margin. This study aimed to determine 'regional' pericolic nodes based on prospective lymph node (LN) mapping.

According to preplanned in vivo measurements of the bowel, the anatomical distributions of the feeding artery and LNs were determined in 2996 stages I-III colon cancer patients who underwent colectomy with resection margin >10 cm at 25 institutions in Japan.

The mean number of retrieved pericolic nodes was 20.9 (standard deviation, 10.8) per patient. In all patients except seven (0.2%), the primary feeding artery was distributed within 10 cm of the primary tumour. The metastatic pericolic node most distant from the primary tumour was within 3 cm in 837 patients, 3-5 cm in 130 patients, 5-7 cm in 39 patients and 7-10 cm in 34 patients. Only four patients (0.1%) had pericolic lymphatic spread beyond 10 cm; all of whom had T3/4 tumours accompanying extensive mesenteric lymphatic spread. The location of metastatic pericolic node did not differ by the feeding artery's distribution. Postoperatively, none of the 2996 patients developed recurrence in the remaining pericolic nodes.

The pericolic nodes designated as 'regional' were those located within 10 cm of the primary tumours, which should be fully considered when determining the bowel resection margin, even in the era of complete mesocolic excision.

Japanese Society for Cancer of the Colon and Rectum.

The development of new technologies based on electronic intelligent images is a very active research and promotion of new technologies in recent years. This article mainly summarizes the basic concept, development, and technology of electronic intelligent imaging technology, as well as the research, promotion, and application of electronic intelligent imaging technology in clinical treatment. It especially emphasizes the practicality and application of electronic intelligent imaging technology in the current clinical operation process and conducts a meta-analysis of the current mesorectal excision, so as to provide more scientific and professional guidance for clinical surgery. The results of the meta-analysis showed that 3291 documents were initially obtained and duplicate documents were deleted by searching for keywords in mesocolon excision. We excluded 2399 subjects and articles whose interventions did not meet the inclusion criteria of this study after reading the title and abstract. Then, we obtained 892 papers that may meet the inclusion criteria through preliminary screening. We further optimized the search strategy based on selection criteria and data integrity filtering principles and finally determined 111 references. 100 articles that did not meet the requirements were excluded, and 11 articles were finally included for meta-analysis. Medical imaging can effectively improve the therapeutic effect of mesocolon excision and reduce the occurrence of complications. Therefore, it is very important to combine medical intelligent images for preoperative evaluation, and the development of the combination of surgical treatment and medical images should not be underestimated in the future.

In the case of right-sided transverse colon cancer (RTCC) and hepatic flexure colon cancer (HFCC), there is a potential connection of lymph drainage between mesentery and greater omentum. However, most previous reports have been limited case series with No. 206 and No. 204 lymph node (LN) dissection for RTCC and HFCC.

The InCLART Study is a prospective observational study aiming to enrol 427 patients with RTCC and HFCC treated at 21 high-volume institutions in China. The prevalence of infrapyloric (No. 206) and greater curvature (No. 204) LN metastasis and short-term outcomes will be investigated in a consecutive series of patients with T2 or deeper invasion RTCC or HFCC, following the principle of complete mesocolic excision with central vascular ligation. Primary endpoints were performed to identify the prevalence of No. 206 and No. 204 LN metastasis. Secondary analyses will be used to estimate prognostic outcomes, intraoperative and postoperative complications, the consistency of preoperative evaluation and postoperative pathological results of LN metastasis.

Ethical approval for the study has been granted by the Ruijin Hospital Ethics Committee (approval number: 2019-081) and has been or will be approved successively by each participating centre's Research Ethics Board. The findings will be disseminated in peer-reviewed publications.

ClinicalTrials.gov Registry (NCT03936530; https://clinicaltrials.gov/ct2/show/NCT03936530).

The extent of lymphadenectomy in patients with pT2 colorectal cancer (CRC) remains controversial. This study aimed to elucidate the effects of D3 and D2 lymph node dissection (LND) on survival in patients diagnosed with pT2 CRC.

This was a retrospective cohort study from a high-volume cancer center in Japan. From April 2007 to December 2020, 6273 patients with primary CRC were included in the study; among these, 616 patients diagnosed with pT2 CRC underwent radical colorectal resection. Propensity score matching (PSM) was applied to balance potential confounding factors, and a total of 104 matched pairs were extracted from the entire cohort. Independent risk factors associated with prognosis were determined by Cox regression analysis. The main outcome measures were overall survival (OS) and cancer-specific survival (CSS).

Before PSM, there was a statistically significant difference across the cohort in OS and CSS (p = 0.000 and 0.013) between D3 and D2 LND groups; the estimated hazard ratio (HR) was 2.2 (95% confidence interval (CI), 1.1-4.4, p = 0.031) for OS in the D3 LND and 4.4 (95% CI, 1.7 to 11, p = 0.0027) for CSS (p = 0.013). There was also a significant difference (p = 0.024) in OS between the D3 and D2 LND groups in the matched cohort, with an estimated HR for OS of 3.3 (95% CI, 1.2 to 9.1, p = 0.024) and an estimated HR for CSS of 7.2 (95% CI, 1.6 to 33, p = 0.011).

D3 LND had a significant survival advantage in the treatment of pT2 CRC. The results of this study provide a theoretical basis for the application of D3 LND in radical surgery for preoperative T2 CRC.