Extent of surgery in cancer of the colon: Is more better?

Clinical validation of 3D virtual modelling for laparoscopic complete mesocolic excision with central vascular ligation for proximal colon cancer

INTRODUCTION

Laparoscopic Complete Mesocolic Excision (CME) with Central Vascular Ligation (CVL) in colon cancer surgery has not been broadly adopted in part because of safety concerns. Pre-operative 3-D virtual modelling (3DVM) may help but needs validation.

METHODS

3DVM were routinely constructed from CT mesenteric angiograms (CTMA) using a commercial service (Visible Patient, Strasbourg, France) for consecutive patients during our CMECVL learning curve over three years. 3DVMs were independently checked versus CTMA and operative findings. CMECVL outcomes were compared versus other patients undergoing standard mesocolic excision (SME) surgery laparoscopically in the same hospital as control. Stakeholders were studied regarding 3DVM use and usefulness (including detail retention) versus CTMA and a physical 3D-printed model.

RESULTS

26 patients underwent 3DVM with intraoperative display during laparoscopic CMECVL within existing workflows. 3DVM accuracy was 96 % re arteriovenous variations at patient level versus CTMA/intraoperative findings including accessory middle colic artery identification in three patients. Twenty-two laparoscopic CMECVL with 3DVM cases were compared with 49 SME controls (age 69 ± 10 vs 70.9 ± 11 years, 55 % vs 53 % males). There were no intraoperative complications with CMECVL and similar 30-day postoperative morbidity (30 % vs 29 %), hospital stay (9 ± 3 vs 12 ± 13 days), 30-day readmission (6 % vs 4 %) and reoperation (0 % vs 4 %) rates. Intraoperative times were longer (215.7 ± 43.9 vs 156.9 ± 52.9 min, p=<0.01) but decreased significantly over time. 3DVM surveys (n = 98, 20 surgeons, 48 medical students, 30 patients/patient relatives) and comparative study revealed majority endorsement (90 %) and favour (87 %).

CONCLUSION

3DVM use was positively validated for laparoscopic CMECVL and valued by clinicians, students, and patients alike.

Standardization of the definition of the types of oncological colectomy. Delphi method for consensus of experts of the Spanish Association of Surgeons

There is no international consensus on the definition of the type of oncological resection that corresponds to each of the colectomies existing in the current literature. The objective is to define for each colectomy described in the literature: embryological dissection plane, vascular pedicles in which to perform central ligation, the extent of the colectomy, and the need for resection of the greater momentum. A consensus of experts is carried out through the Delphi methodology through two rounds from the Coloproctology Section of the Spanish Association of Surgeons. Study period: November 2021-January 2023. 120 experts were surveyed. Degrees of consensus: Very strong: >90%, Strong: 80%-90%, Moderate: 50%-80%, No consensus: <50%. The definition for each oncological colectomy was established by very strong, and strong recommendations. Each oncological colectomy was established as Right hemicolectomy (RHC), RHC with D3 lymphadenectomy, Extended-RHC, transverse colon segmental colectomy, splenic flexure segmental colectomy, subtotal colectomy, total colectomy, left hemicolectomy (LHC), extended-LHC, sigmoidectomy.

A Randomized Phase III Trial of Complete Mesocolic Excision Compared with Conventional Surgery for Right Colon Cancer: Interim Analysis of a Nationwide Multicenter Study of the Italian Society of Surgical Oncology Colorectal Cancer Network (CoME-in trial)

BACKGROUND

Although complete mesocolic excision (CME) is supposed to be associated with a higher lymph node (LN) yield, decreased local recurrence, and survival improvement, its implementation currently is debated because the evidence level of these data is rather low and still not supported by randomized controlled trials.

METHOD

This is a multicenter, randomized, superiority trial (NCT04871399). The 3-year disease-free survival (DFS) was the primary end point of the study. The secondary end points were safety (duration of operation, perioperative complications, hospital length of stay), oncologic outcomes (number of LNs retrieved, 3- and 5-year overall survival, 5-year DFS), and surgery quality (specimen length, area and integrity rate of mesentery, length of ileocolic and middle-colic vessels). The trial design required the LN yield to be higher in the CME group at interim analysis.

RESULTS

Interim data analysis is presented in this report. The study enrolled 258 patients in nine referral centers. The number of LNs retrieved was significantly higher after CME (25 vs. 20; p = 0.012). No differences were observed with respect to intra- or post-operative complications, postoperative mortality, or duration of surgery. The hospital stay was even shorter after CME (p = 0.039). Quality of surgery indicators were higher in the CME arm of the study. Survival data still were not available.

CONCLUSIONS

Interim data show that CME for right colon cancer in referral centers is safe and feasible and does not increase perioperative complications. The study documented with evidence that quality of surgery and LN yield are higher after CME, and this is essential for continuation of patient recruitment and implementation of an optimal comparison. Trial registration The trial was registered at ClinicalTrials.gov with the code NCT04871399 and with the acronym CoME-In trial.

Peculiarities of treatment of patients with complicated forms of the large bowel cancer in conditions of general clinical stationary

Objective. To estimate the structure of complicated forms of colorectal cancer and surgical tactics of treatment in patients with this pathology in conditions of general surgery stationary. Materials and methods. Into the investigation 71 patients were included, treated for complicated forms of colorectal cancer. Results. Primary radical operative interventions were performed in 48 (67.61%) patients, palliative – 18 (25.35%), and symptomatic – 5 (7.04%). Conclusion. The treatment and diagnosis tactics, formatted in the general surgery stationary conditions,leads to certainly high level of morbidity – 45.07% (the complications have occurred in 32 patients),and lethality – 11.27% (8 patients died).

Pattern of recurrence and survival after D2 right colectomy for cancer: is there place for a routine more extended lymphadenectomy?

BACKGROUND

Conventional Right Colectomy with D2 lymphadenectomy (RC-D2) currently represent the most common surgical treatment of right-sided colon cancer (RCC). However, whether it should be still considered a standard of care, or replaced by a routine more extended D3 lymphadenectomy remains unclear. In the present study, we aim to critically review the patterns of relapse and the survival outcomes obtained from our 11-year experience of RC-D2.

METHODS

Clinical data of 489 patients who underwent RC-D2 for RCC at two centres, from January 2009 to January 2020, were retrospectively reviewed. Patients with synchronous distant metastases and/or widespread nodal involvement at diagnosis were excluded. Post-operative clinical-pathological characteristics and survival outcomes were evaluated including the pattern of disease relapse.

RESULTS

We enrolled a total of 400 patients with information follow-up. Postoperative morbidity was 14%. The median follow-up was 62 months. Cancer recurrence was observed in 55 patients (13.8%). Among them, 40 patients (72.7%) developed systemic metastases, and lymph-node involvement was found in 7 cases (12.8%). None developed isolated central lymph-node metastasis (CLM), in the D3 site. The estimated 3- and 5-year relapse-free survival were 86.1% and 84.4%, respectively. The estimated 3- and 5-year cancer-specific OS were 94.5% and 92.2%, respectively.

CONCLUSIONS

The absence of isolated CLM, as well as the cancer-specific OS reported in our series, support the routine use of RC-D2 for RCC. However, D3 lymphadenectomy may be recommended in selected patients, such as those with pre-operatively known CLM, or with lymph-node metastases close to the origin of the ileocolic vessels.

Colon cancer microsatellite instability influences computed tomography assessment of regional lymph node morphology and diagnostic performance

PURPOSE

To elucidate whether a high level of microsatellite instability (MSI-high) in colon cancer influences the CT assessment of regional lymph node (rLN) morphology and diagnostic performance on predicting pathological node-negative (pN0) patients.

METHOD

We retrospectively reviewed 507 patients with cecal/proximal ascending colon cancer (age, 63.0 ± 11.6 years; MSI-stable, n = 398; MSI-high, n = 109) who underwent right hemicolectomy between July 1, 2009, and December 31, 2018. Preoperative CT images were assessed for number of rLNs, long/short diameter of the largest rLN, and CT LN grade (CTN0, low probability of metastasis; CTN1, borderline; CTN2, high probability). Sensitivity, specificity, positive predictive value and negative predictive value for predicting pN0 was calculated. Multivariable logistic regression analysis was performed. Statistical significance was defined as P < 0.05.

RESULTS

A study population of 507 patients (mean age ± standard deviation, 63.0 ± 11.6; 264 women) were evaluated. In patients with rLN metastasis, the rLN long axis (pN1: P = 0.013, pN2: P = 0.039) and short axis (pN1: P = 0.001, pN2: P = 0.009) were both longer in MSI-high tumors compared with MSI-stable tumors. High specificity for predicting pN0 was only achieved in MSI-high tumors [sensitivity_MSI-stable = 58.3% (n = 137/235), specificity_MSI-stable = 71.2% (n = 116/163); sensitivity_MSI-high = 38.4% (n = 33/86), specificity_MSI-high = 91.3% (n = 21/23)]. Multivariable logistic regression indicated MSI-high (P < 0.001, odds ratio = 3.701), smaller LN long axis (P = 0.023, odds ratio = 0.905), and lower CT LN grade (CTN0: P = 0.009, odds ratio = 2.987; CTN1: P = 0.014, odds ratio = 2.195) as significant parameters in predicting pN0.

CONCLUSION

MSI-high colon cancer is associated with larger rLNs and high specificity for predicting pN0 on CT assessment.

Video Context Improves Performance in Identifying Operative Planes on Static Surgical Images

BACKGROUND

Correct identification of the surgical tissue planes of dissection is paramount at the operating room, and the needed skills seem to be improved with realistic dynamic models rather than mere still images. The objective is to assess the role of adding video prequels to still images taken from operations on the precision and accuracy of tissue plane identification using a validated simulation model, considering various levels of surgeons' experience.

METHODS

A prospective observational study was conducted involving 15 surgeons distributed to three equal groups, including a consultant group [C], a senior group [S], and a junior group [J]. Subjects were asked to identify and draw ideal tissue planes in 20 images selected at suitable operative moments of identification before and after showing a 10- second videoclip preceding the still image. A validated comparative metric (using a modified Hausdorff distance [%Hdu] for object matching) was used to measure the distance between lines. A precision analysis was carried out based on the difference in %Hdu between lines drawn before and after watching the videos, and between-group comparisons were analyzed using a one-way analysis of variance (ANOVA). The analysis of accuracy was done on the difference in %Hdu between lines drawn by the subjects and the ideal lines provided by an expert panel. The impact of videos on accuracy was assessed using a repeated-measures ANOVA.

RESULTS

The C group showed the highest preciseness as compared to the S and J groups (mean Hdu 9.17±11.86 versus 12.1±15.5 and 20.0±18.32, respectively, p <0.001) and significant differences between groups were found in 14 images (70%). Considering the expert panel as a reference, the interaction between time and experience level was significant ( F (2, 597) = 4.52, p <0.001). Although the subjects of the J group were significantly less accurate than other surgeons, only this group showed significant improvements in mean %Hdu values after watching the lead-in videos ( F (1, 597) = 6.04, p = 0.014).

CONCLUSIONS

Adding video context improved the ability of junior trainees to identify tissue planes of dissection. A realistic model is recommended considering experience-based differences in precision in training programs.

Postoperative Quality Assessment Score Can Select Patients with High Risk for Locoregional Recurrence in Colon Cancer

BACKGROUND

Monitoring surgical quality has been shown to reduce locoregional recurrence (LRR). We previously showed that the arterial stump length (ASL) after complete mesocolic excision (CME) is a reproducible quality instrument and correlates with the lymph-node (LN) yield. We hypothesized that generating an LRR prediction score by integrating the ASL would predict the risk of LRR after suboptimal surgery.

METHODS

502 patients with curative resections for stage I-III colon cancer were divided in two groups (CME vs. non-CME) and compared in terms of surgical data, ASL-derived parameters, pathological parameters, LRR and LRR-free survival. A prediction score was generated to stratify patients at high risk for LRR.

RESULTS

The ASL showed significantly higher values (50.77 mm ± 28.5 mm) with LRR vs. (45.59 mm ± 28.1 mm) without LRR (p < 0.001). Kaplan-Meier survival analysis showed a significant increase in LRR-free survival at 5.58 years when CME was performed (Group A: 81%), in contrast to non-CME surgery (Group B: 67.2%).

CONCLUSIONS

The prediction score placed 76.6% of patients with LRR in the high-risk category, with a strong predictive value. Patients with long vascular stumps and positive nodes could benefit from second surgery to complete the mesocolic excision.

A novel fluorescent c-met targeted imaging agent for intra-operative colonic tumour mapping: Translation from the laboratory into a clinical trial

BACKGROUND

The c-Met protein is overexpressed in many gastrointestinal cancers. We explored EMI-137, a novel c-Met targeting fluorescent probe, for application in fluorescence-guided colon surgery, in HT-29 colorectal cancer (CRC) cell line and an in vivo murine model.

METHODS

HT-29 SiRNA transfection confirmed specificity of EMI-137 for c-Met. A HT-29 CRC xenograft model was developed in BALB/c mice, EMI-137 was injected and biodistribution analysed through in vivo fluorescent imaging. Nine patients, received a single intravenous EMI-137 bolus (0.13 mg/kg), 1-3 h before laparoscopic-assisted colon cancer surgery (NCT03360461). Tumour and LN fluorescence was assessed intraoperatively and correlated with c-Met expression in eight samples by immunohistochemistry.

FINDINGS

c-Met expression HT-29 cells was silenced and imaged with EMI-137. Strong EMI-137 uptake in tumour xenografts was observed up to 6 h post-administration. At clinical trial, no serious adverse events related to EMI-137 were reported. Marked background fluorescence was observed in all participants, 4/9 showed increased tumour fluorescence over background; 5/9 had histological LN metastases; no fluorescent LN were detected intraoperatively. All primary tumours (8/8) and malignant LN (15/15) exhibited high c-Met protein expression.

INTERPRETATION

EMI-137, binds specifically to the human c-Met protein, is safe, and with further refinement, shows potential for application in fluorescence-guided surgery.

Disease recurrence after right hemicolectomy in Scotland: Is there rationale to adopt complete mesocolic excision (CME)?

AIMS

Complete mesocolic excision (CME) has been proposed as a way to improve the oncological outcomes in patients with colon cancer. To investigate whether there is rationale for adopting the technique in Scotland, our aim was to define the incidence of disease recurrence following standard right hemicolectomy and to compare this with published CME outcomes.

METHODS

Data was collected on consecutive patients undergoing right or extended right hemicolectomy for colonic adenocarcinoma (2012-2017) at three hospitals in Scotland (Raigmore Hospital, Aberdeen Royal Infirmary and Glasgow Royal Infirmary). Emergency or palliative surgery was excluded. Patients were followed up with CT scans and colonoscopy for a minimum of 3 years.

RESULTS

689 patients (M 340, F 349) were included. 30-day mortality was 1.6%. Final pathological stage was Stage I (14%), Stage II (49.8%) and Stage III (36.1%). During follow-up, 10.5% developed loco-regional recurrence and 12.2% developed distant metastases. The 1, 3 and 5-year disease-free survival (DFS) was 94%, 84% and 82% respectively. Primary determinants of recurrence were T stage (p < 0.001), N stage (p < 0.001), apical node involvement (p < 0.001) and EMVI (p < 0.001). When compared to the literature, 30-day mortality was lower than many published series and DFS rates were similar to the largest CME study to date (4 year DFS 85.8% versus 83%).

CONCLUSION

The outcomes of patients undergoing right hemicolectomy in Scotland compare favourably with many published CME studies. The technique demands further evaluation before it can be recommended for adoption into routine surgical practice.

Should there be a specific length of the colon-rectum segment to be resected for an adequate number of lymph nodes in cases of colorectal cancers? A retrospective multi-center study

OBJECTIVES

This study aimed to evaluate the question as to whether there should be a certain length of the colon-rectum segment to be resected for correct lymph node staging in cases with colorectal cancer.

MATERIAL AND METHODS

The files and electronic datas of the patients had been undergone surgery for colorectal cancer between January 2011 and June 2016 were evaluated. The patients were divided into two groups; Group I= ≥ 12 lymph nodes, and Group II= lymph nodes less than 12 ( <12) lymph nodes.

RESULTS

Mean age of the 327 participants in this study was 64.30 ± 12.20. Mean length of resected colon-rectum segment was 25.61 (± 14.07) cm; mean number of dissected lymph nodes was 20.63 ± 12.30. Median length of the resected colon was 24 cm (range: 145-6) in Group I and 20 cm (range: 52-9) in Group II; a significant difference was found between the groups (p= 0.002). Factors associated with adequate lymph node dissection included type of the operation (p= 0.001), tumor location (p= 0.005), tumor T stage (p= 0.001), condition of metastasis in the lymph node (p= 0.008) and stage of the disease (p= 0.031). Overall survival was 62.4 ± 1.31 months, and Group I and Group II survival was 61.4 ± 1.39 months and 66.7 ± 3.25 months, respectively (p= 0.449).

CONCLUSION

Results of the study showed that ≥ 12 lymph nodes would likely be dissected when the length of the resected colon-rectum segment is > 21 cm. We conclude that the removed colonic size can be significant when performed with oncological surgical standardization.

Is radical surgery for clinical stage I right-sided colon cancer relevant? A retrospective review

Purpose

Radical lymph node dissection for right-sided colon cancer is technically challenging. No clear guideline is available for surgical resection of clinical stage I right-sided colon cancer. This study was designed to review the pathologic stage of clinical stage I right-sided colon cancer and determine the relevant extent of surgical resection.

Methods

Patients were treated for clinical stage I right-sided colon cancers (cecal, ascending, hepatic flexure, and proximal transverse colon) between July 2006 and December 2014 at a tertiary teaching hospital. Open surgery was not included because laparoscopic surgery is an initial major procedure in the institution.

Results

During the study period, 80 patients diagnosed with clinical stage I right-sided colon cancer were classified into 2 groups according to the pathology: stage 0/I and II/III. Tumor sizes were larger in the stage II/III group (P = 0.003). The stage II/III group had higher rates of vascular (P = 0.023) and lymphatic invasion (P = 0.023) and lower rates of well differentiation (P = 0.022). During follow-up, 1 case of local and 4 cases of systemic recurrences were found. Multivariate analysis to confirm odds ratios affecting change from clinical stage I to pathological stage II/III showed that tumor size (P = 0.010) and the number of retrieved lymph nodes (P = 0.046) were risk factors.

Conclusion

For right-sided colon cancer, even with clinical stage I included, radical lymph node dissection should be performed for exact staging with sufficient number of lymph nodes. This will help determine appropriate adjuvant treatment, especially in large tumor sizes.

Complete mesocolic excision for colonic cancer

INTRODUCTION

Complete mesocolic excision for colonic cancer is similar in concept to total mesorectal excision for rectal cancer. This review aims to provide the embryological and anatomical rationale behind CME, and to review the current literature on CME, relative to the feasibility via laparoscopy, the oncological adequacy and outcomes.

EVIDENCE ACQUISITION

A literature search was performed at the end of 2017 according the PRISMA guidelines for systematic reviews. Of 3980 articles found, we analyzed 96 articles. Of note, many case series had overlapping populations; there were five review articles, two consensus conference proceedings, six comparative but only one randomized trial.

EVIDENCE SYNTHESIS

The embryonic and anatomical rationale is well described. CME is feasible via laparoscopy, which may facilitate dissection and anatomic precision: no statistically significant differences were found when compared to open CME regarding overall survival. However, morbidity may be higher in the hands of non-expert laparoscopic surgeons.

CONCLUSIONS

Oncological adequacy can be obtained with laparoscopic CME, with increased lymph node retrieval. However, until now, there is no formal proof that CME improves local recurrence or survival.

Protocol for a multicentre randomized clinical trial comparing oncological outcomes of D2 versus D3 lymph node dissection in colonic cancer (COLD trial)

Background

The extent of lymph node dissection in colonic cancer surgery remains arguable, and evidence from RCTs regarding extended lymph node dissection outcomes is lacking. This study aimed to compare the long‐term results of D3 lymph node dissection with those of D2 dissection.

Methods

This is a multicentre RCT. The aim is to enrol 768 patients with primary colonic cancer assigned randomly to D2 or D3 lymph node dissection. The trial is assessing the superiority of 5‐year overall survival as the primary endpoint in patients undergoing D3 lymph node dissection versus D2 dissection. Secondary endpoints include disease‐free survival, short‐term outcomes (30‐day morbidity and mortality), quality of complete mesocolic excision and lymph node dissection, pattern of lymph node metastasis and quality of life in patients following D2 and D3 lymph node dissection. Experience of 20 D3 and 20 D2 lymph node dissections is required for surgeons to participate in the trial. For surgical accreditation four non‐edited videos of procedures will be assessed. Patients will be followed up for 5 years after last patient enrolment. Intention‐to‐treat analysis will be performed.

Discussion

The results of this study will demonstrate whether extended lymph node dissection is superior to standard dissection in terms of oncological outcomes, and will also assess the impact of more extensive surgery on short‐term outcomes and quality of life.

Implementation of 3D printed superior mesenteric vascular models for surgical planning and/or navigation in right colectomy with extended D3 mesenterectomy: comparison of virtual and physical models to the anatomy found at surgery

BACKGROUND

Three-dimensional (3D) printing technology has recently been well approved as an emerging technology in various fields of medical education and practice; e.g., there are numerous studies evaluating 3D printouts of solid organs. Complex surgery such as extended mesenterectomy imposes a need to analyze also the accuracy of 3D printouts of more mobile and complex structures like the diversity of vascular arborization within the central mesentery. The objective of this study was to evaluate the linear dimensional anatomy landmark differences of the superior mesenteric artery and vein between (1) 3D virtual models, (2) 3D printouts, and (3) peroperative measurements.

METHODS

The study included 22 patients from the ongoing prospective multicenter trial "Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic MDCT Angiography," with preoperative CT and peroperative measurements. The patients were operated in Norway between January 2016 and 2017. Their CT datasets underwent 3D volume rendering and segmentation, and the virtual 3D model produced was then exported for stereolithography 3D printing.

RESULTS

Four parameters were measured: distance between the origins of the ileocolic and the middle colic artery, distance between the termination of the gastrocolic trunk and the ileocolic vein, and the calibers of the middle colic and ileocolic arteries. The inter-arterial distance has proven a strong correlation between all the three modalities implied (Pearson's coefficient 0.968, 0.956, 0.779, respectively), while inter-venous distances showed a weak correlation between peroperative measurements and both virtual and physical models.

CONCLUSION

This study showed acceptable dimensional inter-arterial correlations between 3D printed models, 3D virtual models and authentic soft tissue anatomy of the central mesenteric vessels, and weaker inter-venous correlations between all the models, reflecting the highly variable nature of veins in situ.

Complete Mesocolic Excision With Central Vascular Ligation in Comparison With Conventional Surgery for Patients With Colon Cancer - The Experiences at Two Centers

Purpose

Revolutions have occurred over the last 3 decades in the management of patients with colorectal cancer. Most advances were in rectal cancer surgery, especially after the introduction of the total mesorectal excision (TME) by Heald. However, no parallel advances regarding colon cancer surgeries have occurred. In 2009, Hohenberger introduced a new concept trying to translate the survival advantages of TME to patients with colon cancer. This relatively new concept of a complete mesocolic excision (CME) with central vascular ligation (CVL) in the management of patients with colon cancer represents an evolution in operative technique. We performed a comparative study between CME with CVL and conventional surgery for patients with colon cancer at Italian and Egyptian cancer centers, considering surgical quality and clinical outcome.

Methods

Seventy-nine Egyptian patients underwent conventional surgery (non-CME group) while 52 Italian patients underwent CME with sharp dissection between the embryological planes and CVL of the supplying vessels (CME group).

Results

Significantly better results were observed in terms of lymph node yield (CME group: 22.5 vs. non-CME group: 12; P < 0.0001) and lymph node ratio (CME group: 0.03 vs. non-CME group: 0.22; P < 0.0001). Regarding surgical morbidity, no significant difference was noted (CME group: 2 vs. non-CME group: 5; P < 0.702).

Conclusion

CME appears to be a safe procedure when performed by experienced hands through proper embryological planes. It also provides a superior specimen, with a higher lymph node yield, which consequently affects the lymph node ratio. Eventually, CME with CVL should be increasingly adopted and studied more deeply.

Laparoscopic complete mesocolic excision via mesofascial separation for left-sided colon cancer

PURPOSE

To evaluate the safety and feasibility of laparoscopic complete mesocolic excision (CME) via mesofascial separation for left-sided colon cancer.

METHODS

We evaluated prospectively collected data on 65 consecutive patients with stage I-III left-sided colon cancer, who underwent laparoscopic CME between October 2011 and September 2016. After the exclusion of 5 patients who had T4b or other active tumors, 60 patients were the subjects of this analysis. The completeness of CME, preservation of the hypogastric nerve, operative data, pathological findings, complications, and length of hospital stay were assessed.

RESULTS

CME completeness was graded as the mesocolic and intramesocolic plane in 54 and 6 patients, respectively. The hypogastric nerve was preserved in all patients. A total of 17, 12, 28, and 3 patients had T1, T2, T3, and T4a tumors, respectively. The mean number of lymph nodes retrieved was 16.2, and lymph node metastasis was identified in 22 patients. The mean operative time and intraoperative blood loss were 283 min and 38 ml, respectively. One patient had an intraoperative complication and six patients had postoperative complications. The hospital stay was 12 days.

CONCLUSION

Laparoscopic CME via mesofascial separation is a safe and feasible procedure for left-sided colon cancer.

Omega-3 PUFA Loaded in Resveratrol-Based Solid Lipid Nanoparticles: Physicochemical Properties and Antineoplastic Activities in Human Colorectal Cancer Cells In Vitro

New strategies are being investigated to ameliorate the efficacy and reduce the toxicity of the drugs currently used in colorectal cancer (CRC), one of the most common malignancies in the Western world. Data have been accumulated demonstrating that the antineoplastic therapies with either conventional or single-targeted drugs could take advantage from a combined treatment with omega-3 polyunsaturated fatty acids (omega-3 PUFA). These nutrients, shown to be safe at the dosage generally used in human trials, are able to modulate molecules involved in colon cancer cell growth and survival. They have also the potential to act against inflammation, which plays a critical role in CRC development, and to increase the anti-cancer immune response. In the present study, omega-3 PUFA were encapsulated in solid lipid nanoparticles (SLN) having a lipid matrix containing resveratrol esterified to stearic acid. Our aim was to increase the efficiency of the incorporation of these fatty acids into the cells and prevent their peroxidation and degradation. The Resveratrol-based SLN were characterized and investigated for their antioxidant activity. It was observed that the encapsulation of omega-3 PUFA into the SLN enhanced significantly their incorporation in human HT-29 CRC cells in vitro, and their growth inhibitory effects in these cancer cells, mainly by reducing cell proliferation.

Similar length of colon is removed regardless of localization in right-sided colonic cancer surgery

BACKGROUND

Colorectal cancers represent a heterogenous group of tumours. While left segmental colectomy is an accepted and oncologically safe practice for left-sided colonic cancer (CC), some authors suggest that limited segmental resection of right-sided cancer should be debated in order to preserve length of the resected colon. To our knowledge, caecum and ascending CC have not been analysed as different groups of tumours. The objective of this study was to assess if, retrospectively, surgical treatment of caecal cancer differed from ascending CC.

METHODS

A review of all consecutive patients with right colonic resection for cancer admitted to the University hospital of Grenoble from January 2005 to August 2016 was performed. Length of resected colon was compared between caecal primary and ascending CC. Other technical and pathological aspects were analysed such as minimal invasive surgery and number of harvested lymph nodes from anatomic specimens.

RESULTS

Among operated patients, tumour was localized pre-operatively on caecum in 110 cases and on the right ascending colon in 119 cases. Pre-operative localization had no effect on resected colon length (mean 24.5 cm, 24 ± 10.34 versus 25 cm ± 7.28, P = 0.95), on the number of harvested lymph nodes with a mean of 15 (±7.6) nodes in the caecal group versus 15.2 (±7.3) (P = 0.72). We noticed 15 cases of discordance between pre- and post-operative localization (4 versus 11, P = 0.08).

CONCLUSION

Length of resected colon does not differ depending on localization of tumour in our center.

Right colic artery anatomy: a systematic review of cadaveric studies

Background

Complete mesocolic excision for right-sided colon cancer may offer an oncologically superior excision compared to traditional right hemicolectomy through high vascular tie and adherence to embryonic planes during dissection, supported by preoperative scanning to accurately define the tumour lymphovascular supply and drainage. The authors support and recommend precision oncosurgery based on these principles, with an emphasis on the importance of understanding the vascular anatomy. However, the anatomical variability of the right colic artery (RCA) has resulted in significant discord in the literature regarding its precise arrangement.

Methods

We systematically reviewed the literature on the incidence of the different origins of the RCA in cadaveric studies. An electronic search was conducted as per Preferred Reporting Items for Systematic Reviews and Meta-analyses recommendations up to October 2016 using the MESH terms ‘right colic artery’ and ‘anatomy’ (PROSPERO registration number CRD42016041578).

Results

Ten studies involving 1073 cadavers were identified as suitable for analysis from 211 articles retrieved. The weighted mean incidence with which the right colic artery arose from other parent vessels was calculated at 36.8% for the superior mesenteric artery, 31.9% for the ileocolic artery, 27.7% for the root of the middle colic artery and 2.5% for the right branch of the middle colic artery. In 1.1% of individuals the RCA shared a trunk with the middle colic and ileocolic arteries. The weighted mean incidence of 2 RCAs was 7.0%, and in 8.9% of cadavers the RCA was absent.

Conclusions

This anatomical information will add to the technical nuances of precision oncosurgery in right-sided colon resections.

Laparoscopic complete mesocolic excisions for colonic cancer in the last decade: Five-year survival in a single centre

AIM

To analyse clinical and long-term oncologic results after laparoscopic complete mesocolic excision (CME) for colonic cancer over a 10-year period.

METHODS

Consecutive patients who received laparoscopic CME at our hospital from 2007 to 2017 were prospectively registered and retrospectively analysed. In total, 341 patients were included with tumour-nodal-metastasis (TNM) stages 0-III.

RESULTS

The mean age of the patients was 71.9 years. The median length of stay was 5 d. The mean lymph node harvest was 17.8. The mortality rate was 1.2%. Fifteen patients were reoperated on for anastomotic leaks. The local recurrence rate was 2.3%. Five-year TTR and cancer-specific survival CSS were 83.1% and 90.3%. The location of the tumour was not a significant variable for survival in unadjusted and adjusted survival analysis. TNM stage and anastomotic leaks were significant variables with respect to survival.

CONCLUSION

Laparoscopic CME results in acceptable complication rates and long-term oncologic results. It is important to avoid anastomotic leaks because of their negative effect on survival.

Laparoscopic Inferior Mesenteric Artery Peeling: An Alternative to High or Low Vascular Ligation for Sigmoid Colon Cancer Resection

BACKGROUND

In sigmoid cancer, both inferior mesenteric artery high or low ligations are accepted for curative purposes. Since inferior mesenteric artery ligation could compromise blood flow to the anastomosis, potentially increasing anastomotic leakage onset, real oncological benefits and possible disadvantages related to vascular transection level are still on debate. We introduce totally laparoscopic inferior mesenteric artery peeling technique to release from the concept of lymph nodal harvesting linked to arterial transection level.

METHODS

Over a period of 24 months, 31 patients presenting with sigmoid cancer were submitted to laparoscopic sigmoidectomy associated with inferior mesenteric artery peeling. Data on intraoperative and postoperative outcomes have been prospectively collected.

RESULTS

Mean operative time was 180 min (range 110-330 min); mean intraoperative blood loss was 60 ml (range 30-150 ml), and mean postoperative hospitalization was 6.2 days (range 4-11 days). Mean number of lymph node harvested was 16.7 (range 12-28).

CONCLUSIONS

Given a proper selection of patients, laparoscopic sigmoidectomy comprehensive of sub-adventitial IMA skeletonization from its aortic origin could provide good oncological outcomes and recanalization rate. Further data are advocated to confirm these preliminary results.

Lymph node yield in right colectomy for cancer: a comparison of open, laparoscopic and robotic approaches

AIM

Studies have demonstrated a relationship between lymph node (LN) yield and survival after colectomy for cancer. The impact of surgical technique on LN yield has not been well explored.

METHOD

This is a retrospective study of right colectomy (RC) for cancer at a single institution from 2012 to 2014. Exclusion criteria were previous colectomy and emergent and palliative operations. All data were collected by chart review. Primary outcomes were LN yield and the LN to length of surgical specimen (LN-LSS) ratio. Multivariable mixed models were created with surgeon and pathologist as random effects. Sensitivity analyses were performed to exclude Stage IV cancers and to analyse groups on an 'as-treated' basis.

RESULTS

We identified 181 open (O-RC), 163 laparoscopic (L-RC) and 119 robotic (R-RC) right colectomies. O-RC was more commonly performed in women with metastatic disease. The mean LN yield was 28, 29 and 34 in O-RC, L-RC and R-RC, respectively; the respective mean LN-LSS ratios were 0.83, 0.91 and 1.0. The R-RC approach produced a higher LN yield than the other approaches (P < 0.01), and a higher LN-LSS ratio than O-RC (P < 0.01). These findings were unchanged in sensitivity analyses.

CONCLUSION

Robotic right colectomy improves LN yield and the LN-LSS ratio, which may reflect better mesocolic excision. The effect of these findings on survival requires further investigation.

No benefit of extended mesenteric resection with central vascular ligation in right-sided colon cancer

AIM

The optimal extent of mesenteric resection in colon cancer surgery is not known. We have previously shown an increased mortality associated with wider mesenteric resection in right hemicolectomy. This study compares the short- and long-term outcome in three variations of right hemicolectomy based on the position of the vascular ligature in the mesentery.

METHOD

In all, 2084 cases of cancer in the caecum or ascending colon were identified in the Swedish Colorectal Cancer Registry and categorized according to the position of the vascular ligature: central ligation of ileocolic vessels (ICVs) ± right colic vessels (n = 390), central ligation of ICVs + right branch of middle colic vessels (MCVs) (n = 1360) and central ligation of ICVs + central ligation of MCVs (n = 334).

RESULTS

Neither 3-year overall survival, 3-year disease-free survival nor local recurrence rate differed between the groups (P = 0.604; P = 0.247; P = 0.237). There was still no difference after multivariate analysis adjusted for age, sex, American Society of Anesthesiologists classification, TNM stage and adjuvant therapy. An increased peri-operative mortality, however, was observed in extended mesenteric resections, increasing from 0.8% in non-extended to 3.6% in more extended resection, P = 0.025.

CONCLUSION

The study showed no survival benefit by more extended mesenteric resection, indicating that there is no need to extend the mesenteric resection to involve the MCVs in cancer of the caecum or ascending colon. On the contrary, increased peri-operative mortality by more extensive mesenteric resection was noted suggesting that a more conservative approach may be favourable.

Effect of Neoadjuvant Radiation Dose and Schedule on Nodal Count and Its Prognostic Impact in Stage II-III Rectal Cancer

BACKGROUND

It is unknown how neoadjuvant treatment schedule affects lymph node count (LNC) and lymph node ratio (LNR) and how these correlate with overall survival (OS) in rectal cancer (RC).

METHODS

Data were used from the Belgian PROCARE rectal cancer registry on RC patients treated with surgery alone, short-term radiotherapy with immediate surgery (SRT), or chemoradiation with deferred surgery (CRT). The effect of neoadjuvant therapy on LNC was examined using Poisson log-linear analysis. The association of LNC and LNR with overall survival (OS) was studied using Cox proportional hazards models.

RESULTS

Data from 4037 patients were available. Compared with surgery alone, LNC was reduced by 12.3 % after SRT and by 31.3 % after CRT (p < 0.001). In patients with surgery alone, the probability of finding node-positive disease increased with LNC, while after SRT and CRT no increase was noted for more than 12 and 18 examined nodes, respectively. Per node examined, we found a decrease in hazard of death of 2.7 % after surgery alone and 1.5 % after SRT, but no effect after CRT. In stage III patients, the LNR but not (y)pN stage was significantly correlated with OS regardless of neoadjuvant therapy. Specifically, a LNR > 0.4 was associated with a significantly worse outcome.

CONCLUSIONS

Nodal counts are reduced in a schedule-dependent manner by neoadjuvant treatment in RC. After chemoradiation, the LNC does not confer any prognostic information. A LNR of >0.4 is associated with a significantly worse outcome in stage III disease, regardless of neoadjuvant therapy type.

Surgery for Colorectal Cancer - Trends, Developments, and Future Perspectives

BACKGROUND

Although colorectal surgery is long established as the mainstay treatment for colon cancer, certain topics regarding technical fine-tuning to increase postsurgical recurrence-free survival have remained a matter of debate throughout the past years. These include complete mesocolic excision (CME), treatment strategies for metastatic disease, significance of hyperthermic intraperitoneal chemotherapy (HIPEC), and surgical techniques for the treatment of colorectal cancer recurrence. In addition, new surgical techniques have been introduced in oncologic colorectal surgery, and their potential to provide sufficiently radical resection has yet to be proven.

METHODS

A structured review of the literature was performed to identify the current state of the art with regard to the mentioned key issues in colorectal surgery.

RESULTS

This article provides a comprehensive review of the current literature addressing the above-mentioned current challenges in colorectal surgery. The focus lies on the impact of CME and, in relation to this, on lymph node dissection, as well as on treatment of metastatic disease including peritoneal spread, and finally on the treatment of recurrent disease.

CONCLUSION

Uniformly, the current literature reveals that surgery aiming at complete malignancy elimination within multimodal treatment approaches represents the fundamental quantum leap for the achievement of long-term tumor-free survival.

Prognosis of patients with colonic carcinoma before, during and after implementation of complete mesocolic excision

Background

The implementation of complete mesocolic excision (CME) for colonic cancer was accompanied by other important changes, including more patients with early diagnosis by screening and the introduction of adjuvant chemotherapy in patients with stage III disease. The contribution of CME remains unclear.

Methods

In this observational study, data from patients with stage I–III colonic carcinoma were analysed by comparing five time intervals: 1978–1984 (pre-CME), 1985–1994 (CME development), 1995–2002 (CME implementation), 2003–2009 (CME) and 2010–2014 (CME), with a special focus on indicators of process and outcome quality.

Results

During the observed periods, the median age of patients increased (from 65 to 67 years), there were more right-sided carcinomas (from 17·0 to 32·4 per cent), more stage I disease (from 14·0 to 27·7 per cent) and fewer patients with regional lymph node metastases (from 42·7 to 32·0 per cent). The proportion of patients with pN0 disease and at least 12 examined regional lymph nodes increased (from 84·8 to 100 per cent) as did the R0 resection rate (from 97·0 to 100 per cent). Overall morbidity increased, whereas the in-hospital mortality rate was stable (range 1·8–3·7 per cent). Use of adjuvant chemotherapy in stage III colonic carcinoma increased from 0 to 79 per cent. The improvement in outcome quality was more evident in stage III than in stage I–II tumours. In stage III, the 5-year locoregional recurrence rate decreased from 14·8 to 4·1 per cent (P = 0·046) and the 5-year cancer-related survival rate increased from 61·7 to 80·9 per cent (P = 0·010).

Conclusion

With CME, the quality indicators of process and outcome quality improved, especially in stage III colonic carcinoma. Adjuvant chemotherapy in stage III and multidisciplinary approaches in patients with metachronous distant metastases contributed to further outcome improvement.

Complete mesocolic excision and central vascular ligation for colon cancer: Principle, anatomy, surgical technique, and outcomes

Classic colon cancer surgery refers to a wide resection of the tumor-bearing segment and the lymphatics draining along the named artery. The concept of TME has been applied to colon cancer and complete mesocolic excision (CME) in conjuction with central vascular ligation (CVL) has been introduced as the surgical treatment for colon cancer. Here, we discuss appropriate CME procedure with regard to the oncologic backgrounds, essential components, applied anatomy, laparoscopic technique, short-term, and oncologic outcomes. The introduction of CME has improved oncologic outcomes greatly in patients with colon cancer. The improved outcomes with CME can be attributed to underlying sound oncologic principles such as dissection through the proper plane of mesocolic excision, central vascular ligation, and sufficient length of proximal and distal margins. Thereby, CME technique can achieve en bloc removal of the diseased lesion with the increased amount of the colonic mesentery even though the length of for both bowel and mesentery resection remains a matter of debate. CME is a technically demanding operation thus, comprehensive understanding of the applied vascular anatomy is essential for successful CME. Favorable outcomes of open CME have been replicated with a laparoscopic approach. In future perspective, incorporating a structured education program on minimally invasive (laparoscopy or robot) CME would be beneficial.

Complete mesocolic excision and extended (D3) lymphadenectomy for colonic cancer: is it worth that extra effort? A review of the literature

PURPOSE

Recent interest in complete mesocolic excision (CME) with central vascular ligation (CVL) or extended (D3) lymphadenectomy (EL) for curative resection of colon cancer has been driven by published series from experienced practitioners showing excellent survival outcomes and low recurrence rates. In this article, we attempt to clarify the role of CME or EL in modern colorectal surgery.

METHODS

A narrative review of the evidence for CME and EL in the curative treatment of colon cancer.

RESULTS

The principal of CME surgery, similar to total mesorectal excision (TME) for rectal cancer, is the removal of all lymphatic, vascular, and neural tissue in the drainage area of the tumour in a complete mesocolic envelope with intact mesentery, peritoneum and encasing fascia. Extended (D3) lymphadenectomy (EL) is based on similar principles. Sound anatomical and oncological arguments are made to support the principles of removing the tumor contained within an intact mesocolic facial envelope together with an extended lymph node harvest. Excellent oncological outcomes with minimal morbidity and mortality have been reported. This has led to calls for the standardisation of surgery for colon cancer using CME. However, there is conflicting evidence regarding the prognostic benefit of greater lymph node harvests and the evidence for an oncological benefit of CME is limited by methodology flaws and several potential confounding factors.

CONCLUSIONS

Although there is a reasonable anatomical and oncological basis for these techniques, there are no randomised controlled trials from which to draw confident conclusions and there is insufficient consistent high quality evidence to recommend widespread adoption of CME.

Assessment of lymph node involvement in colorectal cancer

Lymph node metastasis informs prognosis and is a key factor in deciding further management, particularly adjuvant chemotherapy. It is core to all contemporary staging systems, including the widely used tumor node metastasis staging system. Patients with node-negative disease have 5-year survival rates of 70%-80%, implying a significant minority of patients with occult lymph node metastases will succumb to disease recurrence. Enhanced staging techniques may help to identify this subset of patients, who might benefit from further treatment. Obtaining adequate numbers of lymph nodes is essential for accurate staging. Lymph node yields are affected by numerous factors, many inherent to the patient and the tumour, but others related to surgical and histopathological practice. Good lymph node recovery relies on close collaboration between surgeon and pathologist. The optimal extent of surgical resection remains a subject of debate. Extended lymphadenectomy, extra-mesenteric lymph node dissection, high arterial ligation and complete mesocolic excision are amongst the surgical techniques with plausible oncological bases, but which are not supported by the highest levels of evidence. With further development and refinement, intra-operative lymphatic mapping and sentinel lymph node biopsy may provide a guide to the optimum extent of lymphadenectomy, but in its present form, it is beset by false negatives, skip lesions and failures to identify a sentinel node. Once resected, histopathological assessment of the surgical specimen can be improved by thorough dissection techniques, step-sectioning of tissue blocks and immunohistochemistry. More recently, molecular methods have been employed. In this review, we consider the numerous factors that affect lymph node yields, including the impact of the surgical and histopathological techniques. Potential future strategies, including the use of evolving technologies, are also discussed.

Complete mesocolic excision: Lessons from anatomy translating to better oncologic outcome

Since the introduction of complete mesocolic excision (CME) for colon cancer, the oncologic outcome of patients has been greatly improved, which has led to a longer survival and a lower recurrence, just like the total mesorectum excision for rectal cancer. Despite the fact that the exact anatomy of the organ is one of the most vital things for surgeons to conduct surgery, no team has really studied the exact structure of the mesocolon and related attachments for CME, until the mesocolonic anatomy was first formally characterized in 2012. Therefore, this article mainly focuses on the anatomy development of the mesocolon and the achievement in this field. Meanwhile, we introduce the latest progress in laparoscopic surgery for colon cancer achieved by our team.

Short-term and oncologic outcomes of laparoscopic and open complete mesocolic excision and central ligation

PURPOSE

To evaluate the pathologic, short-term and oncologic outcomes of laparoscopic and open complete mesocolic excision (CME) and central ligation for right-sided colon cancer.

METHODS

All patients (n = 215) underwent elective CME either by open surgery (n = 99) or laparoscopy (n = 116).

RESULTS

Mean number of retrieved lymph nodes (31 vs. 27, p = 0.012) was greater in the open CME group. Between the open and laparoscopic CME groups, there were no differences of length of the specimen (44.3 cm and 43.2 cm), ileum (14 cm and 13.3 cm), or colon (30.3 cm and 29.8 cm), respectively. Proximal and distal margins were similar. Mean operative time was similar between the open and laparoscopic CME groups (175 min vs. 178 min). The rate of 30-day postoperative complications (36.4% vs. 23.3%, p = 0.036) was higher in the open CME group. There were no differences in 3-year overall survival rates (86.9% vs. 95.5% in stage II disease and 70.2% vs. 90.7% in stage III disease) or recurrence-free survival rates (84.5% vs. 84.8% in stage II disease and 64.2% vs. 68.9% in stage III disease) between the open and laparoscopic CME groups.

CONCLUSIONS

Pathologic (specimen lengths, resection margin lengths, number of lymph nodes, and R0 resection) and oncologic outcomes of the laparoscopic CME group were comparable. Moreover, laparoscopic CME conferred short-term benefits in terms of lower rates of postoperative complications, reduced time to soft diet, and reduced length of hospital stay. Based on these results, laparoscopic CME can be considered as a routine elective approach for right-sided colon cancer.