D3-lymphadenectomy enhances oncological clearance in patients with right colon cancer. Results of a meta-analysis

Advancing precision, safety, and education in D3 lymph node dissection for right hemicolectomy using mixed reality technology

Right hemicolectomy (RHC) is an important treatment for colorectal cancer. The superior mesenteric artery and superior mesenteric vein are known for their significant vascular variations. This study evaluated the short-term outcomes of integrating Mixed Reality (MR) technology into RHC for the treatment of colorectal cancer. Patients who underwent RHC for clinical stage II or III colon cancer between January 2015 and August 2024 were included. Patients were divided into two groups: the MR (+) group (n = 47), in which MR was used, and the MR (-) group (n = 145), in which MR was not used. MR using SYNAPSE VINCENT, Holoeyes MD, and HoloLens2 was utilized for detailed 3D visualization of the vascular anatomy preoperatively and intraoperatively. Forty-four patients per group were matched via propensity score matching and surgical outcomes were compared. In both groups, approximately 70% of the surgeries were performed by the training surgeon. Compared with the MR (-) group, intraoperative blood loss and hospital stay were decreased, and the number of lymph nodes harvested around the middle colic artery/vein were increased without prolonging the operative time in the MR (+) group. MR in RHC offers surgical precision, safety, enhanced patient recovery, and educational value.

Risk of metachronous peritoneal metastases after surgery for obstructive colon cancer: Multivariate analysis from a series of 1,085 patients

BACKGROUND

Data in the literature suggest that obstruction is an independent predictor of poor prognosis in colon cancer. Of all possible sites of recurrence, peritoneal metastases are associated with worse survival. Our aim was to report the incidence of metachronous peritoneal metastases from a cohort of patients undergoing resection of obstructive colon cancer with curative intent and to identify predictive factors for metachronous peritoneal metastases.

METHODS

From 2000 to 2015, a total of 2,325 patients were treated for obstructive colon cancer in French surgical centers, members of the French National Surgical Association (AFC). Patients with palliative management, synchronous metastatic disease, and with postoperative mortality were excluded. A multivariate analysis was performed to determine independent predictive factors of metachronous peritoneal metastases.

RESULTS

The cohort included 1,085 patients. The median follow-up was 21.5 months. Metachronous peritoneal metastases occurred in 12% of patients and were diagnosed after a median interval of 13.5 months. The cumulative 3-year metachronous peritoneal metastasis rate was 10.9%. Three-year overall survival was 85% for patients who did not develop recurrence, 71% for those who develop recurrence without peritoneal metastases, and 56% for those with metachronous peritoneal metastases (P < .0001). In multivariate analysis, 3 variables were identified as independent risk factors for metachronous peritoneal metastases: pT4 stage (odds ratio: 1.98; 95% confidence interval: 1.17-3.36; P = .011), pN2 stage (odds ratio: 2.57; 95% confidence interval: 1.89-4.45; P = .0007), and fewer than 12 lymph nodes examined (odds ratio: 2.01; 95% confidence interval: 1.08-3.74; P = .028).

CONCLUSION

This study showed a significant risk of metachronous peritoneal metastases after curative-intent resection of obstructive colon cancer. The awareness of factors predisposing to metachronous peritoneal metastases could improve the treatment strategy of these patients.

Laparoscopic right hemicolectomy with complete mesocolon excision and cranial approach

BACKGROUND

Complete mesocolon excision (CME) and D3-lymphadenectomy concepts have gained popularity for the surgical treatment of right colon cancer in comparison to the conventional laparoscopic right hemicolectomy (CLRH). The rationale of CME is to dissect the embryological planes between the mesenteric plane and the parietal fascia to remove the mesentery within a complete envelope of mesenteric fascia and visceral peritoneum that contains lymph nodes, the central vascular ligation, and adequate bowel length to remove involved pericolic lymph nodes in the longitudinal direction, having as the main goal to improve the oncological results. CME with D3-lymphadenectomy is challenge since involves the excision of the lymph adipose tissue covering the medial edge of the superior mesenteric vein (SMV) (trunk of Gillot, TG), and the gastrocolic trunk of Henle (GTH). We describe a LRH with CME using a cranial approach allowing an easier central vessels origin identification.

TECHNIQUE

Through the supramesocolic approach, gastrocolic ligament is opened and the GTH and the middle colic artery (MCA) and vein (MCV) origins are identified. Hepatic flexure is mobilized, and a gauze is placed above the mesenteric vessels. Then, the SMV is identified, dividing the ileocolic vessels origin. The plane between the Gerota and Toldt fascias is opened, identifying duodenum, pancreas, and the gauze previously placed. Following this plane and the SMV along the TG, the GTH and its branches are identified. The superior right colic vein, and the MCA and MCV right branches are divided. After that, colon is fully mobilized laterally opening the parietocolic gutter and an intracorporeal anastomosis is performed.

CONCLUSION

CME could lead to an improvement of oncological results due to a wider mesocolic excision in comparison to conventional D2-lymphadenectomy. Cranial approach facilitates the vessels origin identification to perform a true central ligation.

Prospective observational non-randomized trial protocol for surgical planner 3D image processing & reconstruction for locally advanced colon cancer

INTRODUCTION

Colon cancer presents significant surgical challenges that necessitate the development of precise strategies. Standardization with complete mesocolic excision (CME) is common, but some cases require extended resections. This study investigates the use of 3D Image Processing and Reconstruction (3D-IPR) to improve diagnostic accuracy in locally advanced colon cancer (LACC) with suspected infiltration and achieve R0 surgery.

METHODS

Single-center, prospective, observational, comparative, non-randomized study. •Participants: Patients aged > 18 years undergoing LACC surgery, as indicated by CT scans, confirmed via colonoscopy. Exclusion criteria include neoadjuvant therapy, suspected carcinomatosis on CT, and unresectable tumors. •Interventions: 3D-IPR models are used for surgical planning, providing detailed tumor and surrounding structure metrics. Surgical procedures are guided by CT scans and intraoperative findings, categorized by surgical margins as R0, R1, or R2. •Objective: The primary goal is to evaluate 3D-IPR's utility in achieving R0 resection in LACC with suspected infiltration. Secondary objectives include assessing preoperative surgical strategy, comparing CT reports, detecting adenopathy, and identifying vascularization and anatomical variants. • Outcome: The main outcome is the diagnostic accuracy of 3D-IPR in determining tumor infiltration of neighboring structures compared to conventional CT scans, using definitive pathological reports as the gold standard.

RESULTS

•Recruitment and Number Analyzed: The study aims to recruit about 20 patients annually over two years, focusing on preoperative 3D-IPR analysis and subsequent surgical procedures. •Outcome Parameters: These include loco-regional and distant recurrence rates, peritoneal carcinomatosis, disease-free and overall survival, and mortality due to oncologic progression. •Harms: No additional risks from CT scans, as they are mandatory for staging colon tumors. 3D-IPR is derived from these CT scans.

DISCUSSION

If successful, this study could provide an objective tool for precise tumor extension delimitation, aiding decision-making for radiologists, surgeons, and multidisciplinary teams. Enhanced staging through 3D-IPR may influence therapeutic strategies, reduce postsurgical complications, and improve the quality of life of patients with LACC.

TRIAL REGISTRATION

Trial is registered at ISRCTN registry as ISRCTN81005215. Protocol version I (Date 29/06/2023).

Oncologic safety of transverse colon cancer surgery without central vessel ligation of middle colic artery

BACKGROUND

Surgical standardization for transverse colon cancers (TCC) has not been established, and the oncologic benefit of central vessel ligation (CVL) are still unclear. This study aimed to evaluate the oncologic safety of TCC surgery without CVL of the middle colic artery (MCA).

METHODS

This is a single-center, retrospective, observational, comparative study. The clinical, surgical, and pathological characteristics of the patients who underwent radical surgery for non-metastatic TCC between January 2012 and December 2020 were investigated, and the characteristic and oncologic outcomes of No CVL and CVL groups were compared.

RESULTS

The number of No CVL and CVL groups was 47 (44.3%) and 59 (55.7%), respectively. There was no statistically significant difference between the two groups in surgical complications, stage, mean number of retrieved lymph nodes (LN) (24.12 vs. 22.36 p = 0.464), mean number of metastatic LN (1.53 vs. 0.74, p = 0.163), mean proximal margin (19.2 cm vs. 16.7 cm, p = 0.139), mean distal margin (9.6 cm vs. 9.9 cm, p = 0.753), adjuvant chemotherapy, total recurrence rate (6.4 vs. 11.9%, p = 0.507), lymphatic recurrence rate (0.0% vs. 5.1%, p = 0.253), and local recurrence rate (2.1 vs. 1.7%, p = 0.984). Furthermore, there was no statistically significant difference of 5-year disease-free survival (DFS) and overall survival (OS) in stage II (DFS: 94.4 vs. 91.3%, p = 0.685, OS: 94.1 vs. 95.5%, p = 0.838) and stage III (DFS: 88.5 vs. 68.4%, p = 0.253, OS: 100.0% vs. 79.7, p = 0.328).

CONCLUSION

TCC surgery without CVL of the MCA showed comparable surgical and oncologic outcomes compared to surgery with CVL. Therefore, preservation of a branch of the MCA may be considered a safe option, when combined with adequate lymph node dissection, if necessary. A large, prospective, and controlled study will be necessary to provide solid evidence of the oncologic safety of this procedure.

Proposal for standardization of laparoscopic D3 lymphadenectomy for right colon cancer

BACKGROUND

This study presents a laparoscopic surgical protocol for right hemicolectomy and D3 lymphadenectomy (R-D3L) in right colon cancer and reports the oncological outcomes based on a prospective series.

METHODS

The study comprises two phases. In the first phase, a dynamic demonstration of the R-D3L surgical protocol is provided through textual explanation, illustrations, and edited surgical videos. The protocol emphasizes technical steps such as dissection of the embryological plane of the right mesocolon, high tie of ileocolic vessels, surgical trunk of Gillot dissection, and high tie of superior right colic vein (SRCV). In the second phase, a prospective observational study was conducted involving patients undergoing R-D3L surgery with this protocol between July 2015 and July 2021. Demographic, perioperative, and postoperative variables are analyzed, along with anatomopathological variables and oncological outcomes.

RESULTS

A total of 33 patients were analyzed. Median operative time was 202 min. Perioperative bleeding occurred in 6%. Postoperative complications were mild (Clavien-Dindo III in 2%). Postoperative ileus was observed in 15%. No anastomotic dehiscence was reported. The median postoperative stay was 7 days. The median number of resected lymph nodes was 26, with 27% having positive nodes and 70% were classified as stage T3 or T4. After a median follow-up of 45 months, local recurrence, distant recurrence, and carcinomatosis rates were 0%. Mortality rate from other causes was 9%.

CONCLUSION

The surgical protocol shown in the present study could help in the implementation of this technique in those units that consider it appropriate.

Laparoscopic D3 right hemicolectomy with intracorporeal anastomosis

Complete mesocolic excision (CME) with D3 lymphadenectomy for colon cancer has been shown to improve overall as well as disease-free survival compared to conventional right hemicolectomy. Performing a laparoscopic CME/D3 right hemicolectomy with intracorporeal anastomosis (ICA) can be technically demanding even for experienced operators. Here, we present a systematic, standardized approach to the surgery.

Surgical treatment of right colon cancer

The study aimed to perform a systematic review of the literature on surgical treatment for right colon cancer (RCC) with complete mesocolic excision (CME) and D2/D3 lymph node dissection (LND). Material and Methods. A literature review was performed for studies published between 2013 and 2023 by the online resources from the official Web sites of the societies/panels and PubMed database. Sources included guidelines, meta-analyses, randomized and nonrandomized clinical studies, guidelines by European Society of Medical Oncology, the Japanese Society for Cancer of the Colon and Rectum, and the National Comprehensive Cancer Network, Russian clinical guidelines. Results. CME significantly improved both immediate and long-term treatment results, which was confirmed by numerous meta-analyses. The extent of LND remains one of the most controversial issues in RCC. For many Asian surgeons, D3 LND is the standard procedure for the treatment of RCC, whereas the European approach is more conservative and apical lymph node dissection is not mandatory. There are also large differences in understanding the extent of D3 LND in RCC. Most surgeons understand this term as dissection of adipose tissue along the anterior and lateral surface of the superior mesenteric vein, however, there are authors who perform circular dissection along the superior mesenteric vessels, considering this extent of surgery to be the most radical. Conclusion. It is necessary to standardize methods and effective criteria for quality control of CME for RCC and LND. In this case, external independent assessment of the quality of surgical intervention is important. There is also currently a growing number of studies in which intraoperative fluorescence imaging makes it possible to better visualize the location of the apical lymph nodes and individualize LND.

Comparison of D2 vs D3 lymph node dissection for RIght COloN cancer (RICON): study protocol for an international multicenter open-label randomized controlled trial

BACKGROUND

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.

METHODS

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.

DISCUSSION

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.

TRIAL REGISTRATION

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

Complete mesocolic excision for colon cancer: current status and controversies

According to Hohenberger's original description, complete mesocolic excision for colon cancer involves precise dissection of the avascular embryonic plane between the parietal retroperitoneum and visceral peritoneum of the mesocolon. This ensures mesocolic integrity, access to high ligation of the supplying vessels at their origin and an associated extended lymphadenectomy. Results from centres which have adopted this approach routinely have demonstrated that oncological outcomes can be improved by the rigorous implementation of established principles of cancer surgery. Meticulous anatomical dissection along embryonic planes is a well-established principle of precision cancer surgery used routinely by the specialist colorectal surgeon. Therefore, the real question concerns the need for true central vascular ligation and associated extended (D3) lymphadenectomy or otherwise, particularly along the superior mesenteric vessels when performing a right colectomy. Whether this approach results in improved overall or disease-free survival remains unclear and its role remains controversial particularly given the potential for significant morbidity associated with a more extensive central vascular dissection. Current literature is limited by considerable bias, as well as inconsistent and variable terminology, and the results of established randomized trials are awaited. As a result of the current state of equipoise, various national guidelines have disparate recommendations as to when complete mesocolic excision should be performed if at all. This article aims to review the rationale for and technical aspects of complete mesocolic excision, summarize available short and long term outcome data and address current controversies.

Laparoscopic right hemicolectomy: a SICE (Società Italiana di Chirurgia Endoscopica e Nuove tecnologie) network prospective study on the approach to right colon lymphadenectomy in Italy: is there a standard?-CoDIG 2 (ColonDx Italian Group)

BACKGROUND

Colon cancer is a disease with a worldwide spread. Surgery is the best option for the treatment of advanced colon cancer, but some aspects are still debated, such as the extent of lymphadenectomy. In Japanese guidelines, the gold standard was D3 dissection to remove the central lymph nodes (203, 213, and 223), but in 2009, Hoenberger et al. introduced the concept of complete mesocolic excision, in which surgical dissection follows the embryological planes to remove the mesentery entirely to prevent leakage of cancer cells and collect more lymph nodes. Our study describes how lymphadenectomy is currently performed in major Italian centers with an unclear indication on the type of lymphadenectomy that should be performed during right hemicolectomy (RH).

METHODS

CoDIG 2 is an observational multicenter national study that involves 76 Italian general surgery wards highly specialized in colorectal surgery. Each center was asked not to modify their usual surgical and clinical practices. The aim of the study was to assess the preference of Italian surgeons on the type of lymphadenectomy to perform during RH and the rise of any new trends or modifications in habits compared to the findings of the CoDIG 1 study conducted 4 years ago.

RESULTS

A total of 788 patients were enrolled. The most commonly used surgical technique was laparoscopic (82.1%) with intracorporeal (73.4%), side-to-side (98.7%), or isoperistaltic (96.0%) anastomosis. The lymph nodes at the origin of the vessels were harvested in an inferior number of cases (203, 213, and 223: 42.4%, 31.1%, and 20.3%, respectively). A comparison between CoDIG 1 and CoDIG 2 showed a stable trend in surgical techniques and complications, with an increase in the robotic approach (7.7% vs. 12.3%).

CONCLUSIONS

This analysis shows how lymphadenectomy is performed in Italy to achieve oncological outcomes in RH, although the technique to achieve a higher lymph node count has not yet been standardized. Trial registration (ClinicalTrials.gov) ID: NCT05943951.

Prognostic value of lymph node distribution after laparoscopic colectomy with Japanese D3 dissection

PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSION

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

[Personalized evaluation of D3-lymph node dissection complexity for right colorectal cancer considering anatomy of superior mesenteric vessels]

OBJECTIVE

To provide a personalized approach to D3 lymph node dissection (LND) in right colon cancer using a proper analysis and interpretation of CT angiography of superior mesenteric vessels.

MATERIAL AND METHODS

An observational cross-sectional study included 34 patients who underwent surgery for right colon cancer with D3 LND along superior mesenteric artery (SMA) and vein (SMV). Characteristics of surgically relevant vascular anatomy were evaluated as 0 or 1 depending on complexity of anatomical characteristic. Patients were classified into groups of standard (0 points) and complex (1-3 points) LND according to complexity of vascular anatomy.

RESULTS

SMA and SMV crossed each other at the level of ileocolic artery (ICA) orifice or above in 23.5% of cases (n=8). In 76.5% of cases, they passed parallel to each other (n=25). Ileocolic artery passed posteriorly to SMV in 47.1% (n=16) of cases. A closed type of SMA with a restricted access to D3 area was observed in 41.2% of cases (n=14). Duration of LND significantly differed (43.6±17.8 min in standard cases and 61.9±18.6 min in complex ones, p=0.006).

CONCLUSION. V

Ascular anatomy can predict complexity of D3 LND in right colon cancer surgery. The complexity scale is an important tool for preoperative planning of D3 LND and identifying technical difficulties associated with vascular anatomy.

Complete mesocolic excision for right hemicolectomy: an updated systematic review and meta-analysis

PURPOSE

Complete mesocolic excision improves lymphadenectomy for right hemicolectomy and respects the embryological planes. However, its effect on cancer-free and overall survival is questioned. Therefore, we aimed to determine the potential benefits of the technique by performing a systematic review of the literature and meta-analysis of the available evidence.

METHODS

Web of Science, PubMed/Medline, and Embase were searched on February 22, 2023. Original studies on short- and long-term oncological outcomes of adult patients undergoing right hemicolectomy with complete mesocolic excision as a treatment for primary colon cancer were considered for inclusion. Outcomes were extracted and pooled using a model with random effects.

RESULTS

A total of 586 publications were identified through database searching, and 18 from citation searching. Exclusion of 552 articles left 24 articles for inclusion. Meta-analysis showed that complete mesocolic excision increased the lymph node harvest (5 studies, 1479 patients, MD 9.62, 95% CI 5.83-13.41, p > 0.0001, I2 84%), 5-year overall survival (5 studies, 2381 patients, OR 1.88, 95% CI 1.14-3.09, p = 0.01, I2 66%), 5-year disease-free survival (4 studies, 1376 patients, OR 2.21, 95% CI 1.51-3.23, p < 0.0001, I2 0%) and decreased the incidence of local recurrence (4 studies, 818 patients, OR 0.27, 95% CI 0.09-0.79, p = 0.02, I2 0%) when compared to standard right hemicolectomy. Perioperative morbidity was similar between the techniques (8 studies, 3899 patients, OR 1.04, 95% CI 0.89-1.22, p = 0.97, I2 0%).

CONCLUSION

Meta-analysis of observational and randomised studies showed that right hemicolectomy with complete mesocolic excision for primary right colon cancer improves oncologic results without increasing morbidity/mortality. These results need to be confirmed by high-quality evidence and randomised trials in selected patients to assess who may benefit from the procedure.

Variations of the double superior mesenteric vein are not rare: An observational study using computed tomography, three-dimensional image reconstruction, and surgery

INTRODUCTION

Few studies have evaluated variations of the main trunk of the superior mesenteric vessels. Particularly, the double superior mesenteric vein (DSMV) has not been described in detail. This study aimed to establish the definition, anatomical characteristics, and underlying clinical significance of the DSMV.

MATERIALS AND METHODS

A total of 115 patients with colorectal cancer were included in this retrospective study between March 2020 and March 2022. The anatomical characteristics were analyzed using computed tomography, three-dimensional image reconstructions, and surgical videos.

RESULTS

Among the patients enrolled, 22 (19.1%) had DSMVs. The median diameters of the right and left superior mesenteric veins were similar. The superior mesenteric artery was sandwiched between the right and the left superior mesenteric veins. The left superior mesenteric vein mainly crossed the ventral side of the superior mesenteric artery (63.6%). In 1 case, the right superior mesenteric vein was mistakenly resected intraoperatively. The DSMV was classified into types I and II based on whether the right and left trunks formed a common trunk; it was further classified into subtypes a and b based on the colonic vein confluence. The proportions of type I-a, I-b, II-a, and II-b were 4.5%, 27.3%, 9.1%, and 59.1%, respectively. The middle colic veins drained into the left superior mesenteric vein in 19 cases (86.4%).

CONCLUSIONS

The DSMV is more common than previously thought. For the first time, the definition and four types of the DSMV were proposed. The presence of a DSMV should be considered during right hemicolectomies.

Pathways of lymph node metastasis and prognosis after right hemicolectomy for cecal cancer: results from a retrospective single center

BACKGROUND

The recommended operation for cecum cancer (CC) is right hemicolectomy (RH) in some Western countries while the principle of D3 lymphadenectomy in Japan recommends resecting approximately 10 cm from the tumor edge. Therefore, the optimal surgical approach for cecum cancer (CC) remains controversial. We conducted this retrospective study to explore the pattern of lymph node metastasis and better surgical procedures for CC.

METHODS

A total of 224 cecum cancer patients from January 1, 2014, to December 31, 2021, were retrospectively included in the final study. The pattern of lymph node metastasis (LNM) was investigated.

RESULTS

A total of 113 (50.4%, 113/224) patients had pathologically confirmed LNM. The most frequent metastatic site was no. 201 lymph node (46%, 103/224), while 20 (8.9%, 20/224) patients had LNM in no. 202 lymph node, and 8 (3.6%, 8/224) patients had LNM in no. 203 lymph node. Only 1 (0.4%, 1/224) patient had LNM in no. 221 lymph node, four (1.8, 4/224%) patients had LNM in no. 223 lymph node, and no patients had LNM in no. 222 lymph node. LNM in no. 223 lymph node was significantly associated with a poor prognosis. Multivariate analysis indicated that LNM in no. 223 lymph node (HR = 4.59, 95% CI 1.18-17.86, P = 0.028) was the only independent risk factor associated with worse disease-free survival (DFS).

CONCLUSIONS

The LNM in no. 223 lymph node for cecum cancer was rare. Therefore, standard right hemicolectomy excision is too extensive for most CC cases.

Early outcomes from the Minimally Invasive Right Colectomy Anastomosis study (MIRCAST)

BACKGROUND

The impact of method of anastomosis and minimally invasive surgical technique on surgical and clinical outcomes after right hemicolectomy is uncertain. The aim of the MIRCAST study was to compare intracorporeal and extracorporeal anastomosis (ICA and ECA respectively), each using either a laparoscopic approach or robot-assisted surgery during right hemicolectomies for benign or malignant tumours.

METHODS

This was an international, multicentre, prospective, observational, monitored, non-randomized, parallel, four-cohort study (laparoscopic ECA; laparoscopic ICA; robot-assisted ECA; robot-assisted ICA). High-volume surgeons (at least 30 minimally invasive right colectomy procedures/year) from 59 hospitals across 12 European countries treated patients over a 3-year interval The primary composite endpoint was 30-day success, defined by two measures of efficacy-absence of surgical wound infection and of any major complication within the first 30 days after surgery. Secondary outcomes were: overall complications, conversion rate, duration of operation, and number of lymph nodes harvested. Propensity score analysis was used for comparison of ICA with ECA, and robot-assisted surgery with laparoscopy.

RESULTS

Some 1320 patients were included in an intention-to-treat analysis (laparoscopic ECA, 555; laparoscopic ICA, 356; robot-assisted ECA, 88; robot-assisted ICA, 321). No differences in the co-primary endpoint at 30 days after surgery were observed between cohorts (7.2 and 7.6 per cent in ECA and ICA groups respectively; 7.8 and 6.6 per cent in laparoscopic and robot-assisted groups). Lower overall complication rates were observed after ICA, specifically less ileus, and nausea and vomiting after robot-assisted procedures.

CONCLUSION

No difference in the composite outcome of surgical wound infections and severe postoperative complications was found between intracorporeal versus extracorporeal anastomosis or laparoscopy versus robot-assisted surgery.

Surgical and oncological outcomes of laparoscopic right hemicolectomy (D3 + CME) for colon cancer: A prospective single-center cohort study

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

Definition and reporting of lymphadenectomy and complete mesocolic excision for radical right colectomy: a systematic review

BACKGROUND

Several procedures have been proposed to reduce the rates of recurrence in patients with right-sided colon cancer. Different procedures for a radical right colectomy (RRC), including extended D3 lymphadenectomy, complete mesocolic excision and central vascular ligation have been associated with survival benefits by some authors, but results are inconsistent. The aim of this study was to assess the variability in definition and reporting of RRC, which might be responsible for significant differences in outcome evaluation.

METHODS

PRISMA-compliant systematic literature review to identify the definitions of RRC. Primary aims were to identify surgical steps and different nomenclature for RRC. Secondary aims were description of heterogeneity and overlap among different RRC techniques.

RESULTS

Ninety-nine articles satisfied inclusion criteria. Eight surgical steps were identified and recorded as specific to RRC: Central arterial ligation was described in 100% of the included studies; preservation of mesocolic integrity in 73% and dissection along the SMV plane in 67%. Other surgical steps were inconstantly reported. Six differently named techniques for RRC have been identified. There were 35 definitions for the 6 techniques and 40% of these were used to identify more than one technique.

CONCLUSIONS

The only universally adopted surgical step for RRC is central arterial ligation. There is great heterogeneity and consistent overlap among definitions of all RRC techniques. This is likely to jeopardise the interpretation of the outcomes of studies on the topic. Consistent use of definitions and reporting of procedures are needed to obtain reliable conclusions in future trials. PROSPERO CRD42021241650.

Application of 3D-reconstruction and artificial intelligence for complete mesocolic excision and D3 lymphadenectomy in colon cancer

Mathematical algorithms 3D-reconstruction techniques and artificial intelligence are a current line of innovation in colorectal surgical oncology. The objective of this study is to show the initial experience of a 3D image processing and reconstruction system to perform complete mesocolic excision and D3-lymphadenectomy in colon cancer. It is applied to a splenic flexure neoplasm and in a right colon cancer with suspected retroperitoneal infiltration. 3D image processing and reconstruction was employed to delimit 10 cm proximal and distal intestinal margins to the tumor and define its corresponding vascularization. In right colon cancer it showed position and exact dimensions of D3-lymphadenectomy area and possible retroperitoneal fascia infiltration. 3D image processing and reconstruction allows to obtain valuable information from computerized tomography scan. It could be employed during surgical strategy planification to improve oncological results and reduce intraoperative complications.

Is increasing nodal count associated with improved recurrence-free and overall survival following standard right hemicolectomy for colon cancer?

BACKGROUND AND OBJECTIVES

Increasing lymph node harvest for right-sided colon cancer is associated with improved overall survival (OS), but most relevant studies failed to report the extent of resection. We examined the association between increasing lymph node count with standard right hemicolectomy according to nodal status and prognostic outcomes in right-sided tumors.

METHODS

Retrospective analysis of prospectively collected clinical data from patients with proximal colonic adenocarcinomas (n = 1390) following right hemicolectomy. Associations between lymph node counts (0-12 vs. 13-15, 16-20, and >20) and recurrence-free survival (RFS) and OS were examined using multivariate Cox modeling adjusted for confounders.

RESULTS

We found no association between increasing nodal count and RFS, regardless of nodal status. In the absence of nodal metastases, increasing nodal count (16-20 and >20 vs. 0-12 nodes) was associated with 57% (95% confidence interval [CI]: 0.21-0.89) and 52% (95% CI: 0.24-0.95) improved OS, respectively. In the presence of nodal metastases, increasing nodal count was not associated with OS. Adjuvant chemotherapy did not modify this effect.

CONCLUSION

Increasing nodal count (>15 nodes) with right hemicolectomy was not associated with improved RFS. Improved OS was only found for node-negative tumors, casting some doubt on the benefits of resecting more lymph nodes in the presence of nodal metastases.

Is Laparoscopic Complete Mesocolic Excision and Central Vascular Ligation Really Necessary for All Patients With Right-Sided Colon Cancer?

Colon cancer treatment is on the way to evolution over several decades. The minimally invasive surgery has improved postoperative short-term outcomes. Adjuvant chemotherapy has prolonged the survival of advanced colon cancer patients. Hohenberger proposed the noble concept of complete mesocolic excision (CME) which consists of 3 components: plane surgery, sufficient longitudinal bowel resection, and central vascular ligation (CVL). Mesocolic plane surgery shares the same surgical principle of total mesorectal excision, which is maintaining the intact mesothelial envelope. However, there remain debates about the extent of bowel resection and the level of CVL for maximizing lymph node dissection. There is no solid clinical evidence for the oncological necessity and benefit of extended radical dissection in right hemicolectomy. CME with CVL based on open surgery has been adopted in laparoscopic surgery. So, it is also necessary to look at how the CME could be transformed and successfully implanted in the laparoscopic era. Recent rapid advances in surgical technology and cancer biology are preparing for fundamental changes in cancer surgery. In this study, we reviewed the history, oncological necessity, and compatibility of CME for the right hemicolectomy in the laparoscopic era and outline the new perspectives on the evolution of cancer surgery.

Central vascular ligation and mesentery based abdominal surgery

In the nineteenth century the idea of a correct surgical approach in oncologic surgery moved towards a good lymphadenectomy. In colon cancer the segment is removed with adjacent mesentery, in gastric cancer or pancreatic cancer a good oncologic resection is obtained with adequate lymphadenectomy. Many guidelines propose a minimal lymph node count that the surgeon must obtain. Therefore, it is essential to understand the adequate extent of lymphadenectomy to be performed in cancer surgery. In this review of the current literature, the focus is on "central vascular ligation", understood as radical lymphadenectomy in upper and lower gastrointestinal cancer, the evolution of this approach during the years and the improvement of laparoscopic techniques. For what concerns laparoscopic surgery, the main goal is to minimize post-operative trauma introducing the "less is more" concept whilst preserving attention for oncological outcomes. This review will demonstrate the importance of a scientifically based standardization of oncologic gastrointestinal surgery, especially in relation to the expansion of minimally invasive surgery and underlines the importance to further investigate through new randomized trials the role of extended lymphadenectomy in the new era of a multimodal approach, and most importantly, an era where minimally invasive techniques and the idea of "less is more" are becoming the standard thought for the surgical approach.