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

Simultaneous, Multi-Channel, Near-Infrared Fluorescence Visualization of Mesenteric Lymph Nodes Using Indocyanine Green and Methylene Blue: A Demonstration in a Porcine Model

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

Anatomic patterns and clinical significance of gastrocolic trunk of Henlé in laparoscopic right colectomy for colon cancer: Results of the HeLaRC trial

BACKGROUND

Recent interest in laparoscopic right colectomy with D3 lymphadenectomy for right colon cancer, has raised renewed attention to the anatomic variations of the gastrocolic trunk of Henlé (GTH). Understanding the vascular structure of the GTH region for individual patients should improve surgical outcomes. The goal of this nationwide multicenter study (Anatomical Classification of Henlé's Trunk in Laparoscopic Right Hemi-colectomy (HeLaRC) trial) was to study the anatomic patterns of the GTH region, to clarify the implications of GTH in laparoscopic right colectomy with D3 lymphadenectomy (D3-RC) and analyze their clinical significance.

METHODS

We enrolled 583 patients from 26 centers across China who underwent D3-RC. The number of tributaries, length and types of GTH constitutions and their influence on intra-operative data were investigated. A nomogram score (based on the length of GTH, body mass index (BMI), tumor location, T stage and type of GTH (type I vs. non-type I) was established to assess the potential hazard of bleeding.

RESULTS

The GTH was found in 567 patients (97.3%). The distribution of GTH types was 0 (14.1%, n = 80), I (53.3%, n = 302), II (27.0%, n = 153), III (5.6%, n = 32). Of note, the type I GTH, T1 stage and tumor location at ileocecal or ascending colon were correlated with shorter exposure time of the GTH region (P < 0.0001). Short length of GTH (P = 0.002) and tumor location (transverse colon vs. non transverse colon) (P = 0.003) were correlated with the amount of GTH bleeding during the surgery. Nomogram discrimination was good (C-index: 0.72 (95% CI: 0.64, 0.80)). The dissection plane was better in patients with type I GTH than with other types (P = 0.023).

CONCLUSION

GTH pattern variations may affect surgical outcomes in patients undergoing D3-RC. Better recognition of GTH anatomy might lead to a safer operation with better oncologic quality.

Minimally invasive total adventitial resection of the cardia for tumours of the oesophagogastric junction

PURPOSE

A cohort study analysing phases and outcomes of the learning curve required to master minimally invasive total adventitial resection of the cardia.

METHODS

Data from 198 consecutive oesophagectomies performed by a single surgeon was collected prospectively. Patients' stratification reflected chronologically and technically the four main phases of the learning curve: open surgery (open total adventitial resection of the cardia (TARC), n = 45), hybrid Ivor Lewis oesophagectomy (HILO, n = 50), laparoscopic-thoracoscopic assisted (LTA, n = 56) and totally minimally invasive TARC (TMI TARC, n = 47). Operating time, hospital stay, specimen lymph nodes and resection margins were analysed. Five-year survival was the main long-term outcome measured.

RESULTS

Overall 5-year survival was 45%. Perioperative mortality was 1.5% (n = 3). Hospital stay was 22 ± 23 days. Specimen lymph node median was 20 (range: 15-26). Resection margins were negative (R = 0, American College of Pathologists) in 193 cases (97.4%). Five-year survival in the four phases was 37.8%, 44.9%, 42.9% and 55.3%, showing a positive trend towards the end of the learning curve (p = 0.024). Median specimen lymph nodes was 20 (range: 15-22) for open TARC, 18.5 (13-25) for HILO, 19.5 (15-25) for LTA and 23 (18-30) for TMI TARC (p = 0.006). TMI TARC, adenocarcinoma, R >0, T >2, N >0 and LyRa (ratio positive/total specimen nodes) were associated with survival on univariate analysis. T >2 and LyRa independently predicted worse survival on multivariate analysis. CUSUM analysis showed surgical proficiency gain since laparoscopy was introduced.

CONCLUSION

Mastering minimally invasive TARC requires a long learning curve. TMI TARC is safe and oncologically appropriate and may benefit long-term survival: it should be validated by randomised trials as a standardised anatomical resection for tumours of the oesophagogastric junction.

Unravelling the Mysteries of the Mesentery

The mesentery and its folds tether the small bowel loops to the posterior abdominal wall. It transmits nerves, vessels, and lymph ensconced in a fatty sponge layer wrapped in a thin glistening peritoneum, from and to the small bowel. Not only does this flexible dynamic fatty apron house various localized primary benign and malignant lesions, it is often involved in and gives an indication of generalized or systemic diseases in the body. An understanding of the anatomy, components, and function of the mesentery helps to classify mesenteric abnormalities. This further allows for characterizing radiological patterns and appearances specific to certain disease entities. Recent reviews of mesenteric anatomy have kindled new interest in its function and clinical applications, heralding the possibility of revision of its role in diseases of the abdomen.

Laparoscopic Versus Open Complete Mesocolon Excision in Right Colon Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Laparoscopic complete mesocolon excision (LCME) for right colonic cancer improves oncological outcomes. This systematic review and meta-analysis aimed to compare intraoperative, postoperative, and oncological outcomes after LCME and open total mesocolon excision (OCME) for right-sided colonic cancers.

METHODS

Literature searches of electronic databases and manual searches up to January 31, 2019, were performed. Random-effects meta-analysis model was used. Review Manager Version 5.3 was used for pooled estimates.

RESULTS

After screening 1334 articles, 10 articles with a total of 2778 patients were eligible for inclusion. Compared to OCME, LCME improves results in terms of overall morbidity (OR = 1.48, 95% CI 1.21 to 1.80, p = 0.0001), blood loss (MD = 56.56, 95% CI 19.05 to 94.06, p = 0.003), hospital stay (MD = 2.18 day, 95% CI 0.54 to 3.83, p = 0.009), and local (OR = 2.12, 95% CI 1.09 to 4.12, p = 0.03) and distant recurrence (OR = 1.63, 95% CI 1.23-2.16, p = 0.0008). There was no significant difference regarding mortality, anastomosis leakage, number of harvested lymph nodes, and 3-year disease-free survival. Open approach was significantly better than laparoscopy in terms of operative time (MD = - 34.76 min, 95% CI - 46.01 to - 23.50, p < 0.00001) and chyle leakage (OR = 0.41, 95% CI 0.18 to 0.96, p = 0.04).

CONCLUSIONS

This meta-analysis suggests that LCME in right colon cancer surgery is superior to OCME in terms of overall morbidity, blood loss, hospital stay, and local and distant recurrence with a moderate grade of recommendation due to the retrospective nature of the included studies.

Long-term outcomes after complete mesocolic excision for colon cancer at a tertiary care center in Saudi Arabia

BACKGROUND

Data on long-term survival and recurrence of cancer after complete mesocolic excision (CME) for colon cancer has not been reported from our center and related to international data.

OBJECTIVE

Describe overall and disease-free survival, survival by surgery site and stage, and recurrence rates after curative surgery.

DESIGN

Retrospective chart review.

SETTINGS

Academic tertiary care center.

PATIENTS AND METHODS

The study included all patients who underwent either laparoscopic or open surgery for colon cancer with curative intent between 2001 and 2011. The colorectal database was reviewed for the following: demographic data, comorbidities, radiologic investigations, clinical stage, type of operation, complications, pathologic assessment, adjuvant treatment, recurrence and survival. Survival and recurrence rates were calculated, and survival curves were generated.

MAIN OUTCOME MEASURES

5-year overall survival, secondary endpoints were 5-year disease-free survival, survival by surgery site and stage, and recurrence rates.

SAMPLE SIZE

220.

RESULTS

The mean (SD) age at diagnosis was 57 (13) years (CI 95%: 55-59 years). There were 112 males. Mean (SD) body mass index was 27.6 (5.7) kg/m² (CI 95%: 27-28). Pathological assessment revealed R0 (microscopically margin-negative) resection in 207 (94%). The overall 5-year survival and disease-free survival was 77.9% and 70%, respectively. The 5-year disease-free survival was 69% for the sigmoid/left colon and 69% for the right colon (difference statistically nonsignificant). Stages at the time of resection were stage 0 for 2 (0.01%) patients, stage I for 18 (8%), stage II for 92 (42%), stage III for 100 (46%), and stage IV for 6 (3%). The 5-year overall survival by stages I, II, III and IV was 94%, 80%, 75% and 50%, respectively (difference statistically non-significant). The overall 5-year recurrence rate was 23.4%.

CONCLUSION

The outcomes of surgical treatment for colon cancer at our institution are equivalent to international sites. No difference was noted between left and right colon in terms of survival after CME.

LIMITATIONS

Single center, retrospective, small sample size.

CONFLICT OF INTEREST

None.

Wuda granule, a traditional Chinese herbal medicine, ameliorates postoperative ileus by anti-inflammatory action

BACKGROUND

Postoperative ileus (POI) is a temporary disturbance in gastrointestinal motility following surgery, and intestinal inflammatory response plays a critical role in the pathogenesis of POI. Wuda granule (WDG), a gastrointestinal prokinetic Chinese herbal medicine, is prescribed to promote recovery of gastrointestinal function after abdominal surgery. However, it has remained unclear whether WDG shows anti-inflammatory effects in POI. In the present study, we investigated the effects of WDG in a rat POI model and attempted to clarify the detailed mechanisms of action.

METHOD

Experimental POI was induced in adult male SD rats by intestinal manipulation (IM). WDG were orally administered after surgery at the same points (6 h, 12 h, 18 h, 24 h). Histological changes of mesenterium, levels of cytokines, and CD68 and iNOS expression were determined in rats treated or not with WDG. We also investigated the transcriptome profile of rats treated with WDG in a POI model.

RESULTS

Experimental POI in rats was characterized by a marked intestinal and systemic inflammatory response. WDG significantly inhibited the infiltration of neutrophils and macrophages, reduced the levels of IL-6, and CRP, and inhibited protein expressions of CD68 and iNOS in mesentery. Comparison analysis showed that there are 1432 differentially expressed genes (DEGs) between the POI and CON sample, whereas 331 DEGs between the WDG -treated sample and the POI group. And 16 DEGs were shared by the POI vs CON and WDG vs POI groups, among which 6 hub genes associated with immune system processes were identified and verified.

CONCLUSIONS

WDG treatment ameliorates the impaired gastrointestinal motility in the rat model of POI through inhibiting the inflammatory response of mesentery.

Prospective randomized controlled trial to compare laparoscopic distal gastrectomy (D2 lymphadenectomy plus complete mesogastrium excision, D2 + CME) with conventional D2 lymphadenectomy for locally advanced gastric adenocarcinoma: study protocol for a randomized controlled trial

Background

Although radical gastrectomy with D2 lymph node dissection has become the standard surgical approach for locally advanced gastric cancer, patients still have a poor prognosis after operation. Previously, we proposed laparoscopic distal gastrectomy (D2 lymphadenectomy plus complete mesogastrium excision [D2 + CME]) as an optimized surgical procedure for locally advanced gastric cancer. By dissection along the boundary of the mesogastrium, D2 + CME resected proximal segments of the dorsal mesogastrium completely with less blood loss, and it improved the short-term surgical outcome. However, the oncologic therapeutic effect of D2 + CME has not yet been confirmed.

Methods/design

A single-center, prospective, parallel-group, randomized controlled trial of laparoscopic distal gastrectomy with D2 + CME versus conventional D2 was conducted for patients with locally advanced gastric cancer at Tongji Hospital, Wuhan, China. In total, 336 patients who met the following eligibly criteria were included and were randomized to receive either the D2 + CME or D2 procedure: (1) pathologically proven adenocarcinoma; (2) 18 to 75 years old; cT2–4, N0–3, M0 at preoperative evaluation; (3) expected curative resection via laparoscopic distal gastrectomy; (4) no history of other cancer, chemotherapy, or radiotherapy; (5) no history of upper abdominal operation; and (6) perioperative American Society of Anesthesiologists class I, II, or III. The primary endpoint is 3 years of disease-free survival. The secondary endpoints are overall survival, recurrence pattern, mortality, morbidity, postoperative recovery course, and other parameters.

Discussion

Previous studies have demonstrated the safety and feasibility of D2 + CME for locally advanced gastric cancer; however, there is still a lack of evidence to support its therapeutic effect. Thus, we performed this randomized trial to investigate whether D2 + CME can improve oncologic outcomes of patients with locally advanced gastric cancer. The findings from this trial may potentially optimize the surgical procedure and may improve the prognosis of patients with locally advanced gastric cancer.

Trial registration

ClinicalTrials.gov, NCT01978444. Registered on October 31, 2013.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2790-5) contains supplementary material, which is available to authorized users.

Feasibility of fluorescence lymph node imaging in colon cancer: FLICC

BACKGROUND

In colon cancer, appropriate tumour excision and associated lymphadenectomy directly impact recurrence and survival outcomes. Currently, there is no standard for mesenteric lymphadenectomy, with a lymph node yield of 12 acting as a surrogate quality marker. Our goal was to determine the safety and feasibility of indocyanine green (ICG) fluorescence imaging to demonstrate lymphatic drainage in colon cancer in a dose-escalation study.

METHODS

A prospective pilot study of colon cancer patients undergoing curative laparoscopic resection was performed. At surgery, peritumoural subserosal ICG injection was done to demonstrate lymphatic drainage of the tumour. A specialized fluorescence system excited the ICG and assessed lymphatics in real time. The primary outcome was the feasibility of ICG fluorescent lymphangiography for lymphatic drainage in colon cancer. Secondary outcomes were the optimal protocol for dose, injection site, and ICG lymphatic mapping timing.

RESULTS

Ten consecutive patients were evaluated (six males, mean age 69.5 years). In all, lymphatic channels were seen around the tumour to a varying extent. Eight (80%) had drainage to the sentinel node. In all cases where the lymphatic map was seen, there was no further spread 10 min after injection. In 2 patients (20%), additional lymph nodes located outside of the proposed resection margins were demonstrated. In both cases the resection was extended to include the nodes and in both patients these nodes were positive on histopathology. Factors contributing to reduced lymphatic visualization were inadequate ICG concentrations, excess India ink blocking drainage, and inflammation from tattoo placement.

CONCLUSIONS

ICG can be safely injected into the peritumoural subserosal and demonstrate lymphatic drainage in colon cancer. This proof of concept and proposed standards for the procedure can lead to future studies to optimize the application of image-guided precision surgery in colon cancer. Furthermore, this technique may be of value in indicating the need for more extended lymphadenectomy.