Proximal segmentation of the dorsal mesogastrium reveals new anatomical implications for laparoscopic surgery

The number of mesogastria containing metastatic lymph nodes predicts gastric cancer prognosis

BACKGROUND

Previous studies have established the existence of the mesogastrium, dividing it into 6 sections. The mesogastrium is identified during surgery and used in surgical practice. The aim of the present study was to further investigate its role in gastric cancer prognosis.

METHODS

Between January 2014 and January 2018, patients from the Tongji Hospital were included in this post hoc analysis, including data from a randomized clinical study (DCGC01; http://www.

CLINICALTRIALS

gov, NCT01978444). Mesogastria containing metastatic lymph nodes were referred to as metastatic mesogastria. Pathology reports were examined to assess metastases in the mesogastrium. Survival was assessed using Kaplan-Meier curves and multivariable Cox models.

RESULTS

Among the 479 patients, 230 (48.0%) had no lymph node metastasis, 34 (7.1%) had 1 metastatic mesogastrium, and 215 (44.9%) had 2 to 6 metastatic mesogastria. Multivariate analysis showed that the number of metastatic mesogastria and N stages were independent risk factors for patient prognosis. In general, a higher metastatic mesogastrium number is positively correlated with a worse prognosis. For identical N stages, 5-year survival rates for patients with 2 to 6 metastatic mesogastria were significantly lower than those for patients with 1 metastatic mesogastrium.

CONCLUSION

The number of metastatic mesogastria serves as an independent prognostic factor from the N stage.

Feasibility and value of modular splenic hilar lymphadenectomy technique in laparoscopic total gastrectomy: a retrospective-controlled research

BACKGROUND

This study aims to investigate the feasibility and value of modular splenic hilar lymphadenectomy (MSHL) in LTG for advanced PGC located at the greater curvature.

STUDY DESIGN

A retrospective-controlled research included 54 patients diagnosed with advanced PGC located at the greater curvature who underwent LTG combined with spleen-preserving hilar lymphadenectomy between January 2020 and December 2022 at the same treatment center. A total of 20 patients underwent classic splenic hilar lymphadenectomy (CSHL) using a medial approach (classic group), while 34 patients underwent MSHL (modular group). We summarized the technical points, caveats, and critical steps of the MSHL technique and observed and compared clinical indexes between the two groups.

RESULTS

All operations were successful without conversion to laparotomy. The mean operation time, mean splenic hilar lymph node dissection (LND) time, median intraoperative blood loss, and blood loss from splenic hilar LND were all significantly lower in the modular group than in the classic group (p < 0.05). The amount of NO.10 lymph nodes (LNs) was significantly higher in the modular group than in the classic group (p < 0.05). In the classic group, one patient experienced intraoperative splenic vein injury, and one experienced spleen laceration, whereas no intraoperative complications occurred in the modular group. The median postoperative feeding time, exhaust time, defecation time, and postoperative stay were all significantly lower in the modular group compared to the classic group (p < 0.05). In the modular group, one patient experienced Clavien-Dindo I complication and one Clavien-Dindo II complication, while in the classic group, one patient experienced Clavien-Dindo II complication and one Clavien-Dindo IIIa complication. There were no patient was re-hospitalized within 30 days after surgery.

CONCLUSION

The modular splenic hilar LND technique can simplify complicated surgical procedures in SPSHL and reduce the risk of intraoperative bleeding and collateral damage.

The short- and long-term outcomes of laparoscopic D2 lymphadenectomy plus complete mesogastrium excision for lymph node-negative gastric cancer

BACKGROUND

Patients with T1-3N0M0 gastric cancer (GC) who undergo radical gastrectomy maintain a high recurrence rate. The free cancer cells in the mesogastric adipose connective tissue (Metastasis V) maybe the reason for recurrence in these individuals. We aimed to evaluate whether D2 lymphadenectomy plus complete mesogastrium excision (D2 + CME) was superior to D2 lymphadenectomy with regard to safety and oncological efficacy for T1-3N0M0 GC.

METHODS

Patients with T1-3N0M0 GC who underwent radical resection from January 2014 to July 2018 were retrospectively analyzed; there were 323 patients, of whom 185 were in the D2 + CME group and 138 in the D2 group. The primary endpoint was 5-year disease-free survival (DFS). Secondary endpoints include the 5-year overall survival (OS), recurrence pattern, morbidity, mortality, and surgical outcomes.

RESULTS

D2 + CME was associated with less intraoperative bleeding loss, a greater number of lymph nodes harvested, and less time to first postoperative flatus, but the postoperative morbidity was similar. The 5-year DFS was 95.6% (95% CI 92.7-98.5%) and 90.4% (95% CI 85.5-95.3%) in the D2 + CME group and the D2 group, respectively, with a hazard ratio (HR) of 0.455 (95% CI 0.188-1.097; p = 0.071). In terms of recurrence patterns, local recurrence was more prone to occur in the D2 group (p = 0.031). Subgroup analysis indicated that for patients with T1b-3N0M0 GC, the 5-year DFS in the D2 + CME group was considerably greater than that in the D2 group (95.3% [95% CI 91.6-99.0%] vs. 87.6% [95% CI 80.7-94.5%], HR 0.369, 95% CI 0.138-0.983; log-rank p = 0.043).

CONCLUSION

Laparoscopic D2 + CME for T1-3N0M0 GC is safe and feasible. Furthermore, it not only reduces the local recurrence rate but also improves the 5-year DFS in cases of T1b-3N0M0 GC.

Short-Term Outcomes after D2 Gastrectomy with Complete Mesogastric Excision in Patients with Locally Advanced Gastric Cancer: A Systematic Review and Meta-Analysis of High-Quality Studies

Complete mesogastric excision (CME) has been advocated to allow for a more extensive retrieval of lymph nodes, as well as lowering loco-regional recurrence rates. This study aims to analyze the short-term outcomes of D2 radical gastrectomy with CME compared to standard D2 gastrectomy. A systematic review of the literature was conducted according to the Cochrane recommendations until 2 July 2023 (PROSPERO ID: CRD42023443361). The primary outcome, expressed as mean difference (MD) and 95% confidence intervals (CI), was the number of harvested lymph nodes (LNs). Meta-analyses of means and binary outcomes were developed using random effects models to assess heterogeneity. The risk of bias in included studies was assessed with the RoB 2 and ROBINS-I tools. There were 13 studies involving 2009 patients that were included, revealing a significantly higher mean number of harvested LNs in the CME group (MD: 2.55; 95% CI: 0.25-4.86; 95%; p = 0.033). The CME group also experienced significantly lower intraoperative blood loss, a lower length of stay, and a shorter operative time. Three studies showed a serious risk of bias, and between-study heterogeneity was mostly moderate or high. Radical gastrectomy with CME may offer a safe and more radical lymphadenectomy, but long-term outcomes and the applicability of this technique in the West are still to be proven.

A new membrane anatomy-oriented classification of radical surgery for rectal cancer

For patients with different clinical stages of rectal cancer, tailored surgery is urgently needed. Over the past 10 years, our team has conducted numerous anatomical studies and proposed the "four fasciae and three spaces" theory to guide rectal cancer surgery. Enlightened by the anatomical basis of the radical hysterectomy classification system of Querleu and Morrow, we proposed a new classification system of radical surgery for rectal cancer based on membrane anatomy. This system categorizes the surgery into four types (A-D) and incorporates corresponding subtypes based on the preservation of the autonomic nerve. Our surgical classification unifies the pelvic membrane anatomical terminology, validates the feasibility of classifying rectal cancer surgery using the theory of "four fasciae and three spaces," and lays the theoretical groundwork for the future development of unified and standardized classification of radical pelvic tumor surgery.

Complete mesogastric excision for gastric cancer: is it the future of gastric cancer surgery?

Gastric cancer remains undoubtedly one of the most common and deadly cancers worldwide. The global incidence shows wide geographic variation with a high prevalence in Asia. Besides that, there are evident differences in epidemiology, histopathology, tumor location, diagnosis and treatment strategy between east and west countries. Gastric cancer represents an aggressive disease, with many factors influencing its development and also recurrence after surgical resection. New knowledge of disease spread and new routes of metastases are now emerging and the 'novel' concept of complete mesogastric excision for gastric cancer is under consideration and debate. This article aims to analyze and highlight this new concept after a careful literature review, offering also a view toward the future.

New classification system for radical rectal cancer surgery based on membrane anatomy

BACKGROUND

Total mesorectal excision along the "holy plane" is the only radical surgery for rectal cancer, regardless of tumor size, localization or even tumor stage. However, according to the concept of membrane anatomy, multiple fascial spaces around the rectum could be used as the surgical plane to achieve radical resection.

AIM

To propose a new membrane anatomical and staging-oriented classification system for tailoring the radicality during rectal cancer surgery.

METHODS

A three-dimensional template of the member anatomy of the pelvis was established, and the existing anatomical nomenclatures were clarified by cadaveric dissection study and laparoscopic surgical observation. Then, we suggested a new and simple classification system for rectal cancer surgery. For simplification, the classification was based only on the lateral extent of resection.

RESULTS

The fascia propria of the rectum, urogenital fascia, vesicohypogastric fascia and parietal fascia lie side by side around the rectum and form three spaces (medial, middle and lateral), and blood vessels and nerves are precisely positioned in the fascia or space. Three types of radical surgery for rectal cancer are described, as are a few subtypes that consider nerve preservation. The surgical planes of the proposed radical surgeries (types A, B and C) correspond exactly to the medial, middle, and lateral spaces, respectively.

CONCLUSION

Three types of radical surgery can be precisely defined based on membrane anatomy, including nerve-sparing procedures. Our classification system may offer an optimal tool for tailoring rectal cancer 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.

Comparison of short-term surgical outcomes between complete mesenteric resection and traditional transhiatal laparoscopic surgery for Siewert type II/III esophagogastric junction adenocarcinoma

PURPOSE

To explore the effectiveness and safety of laparoscopic transhiatal complete mesenteric resection (CME) surgery compared with those of the traditional laparoscopic transhiatal approach in the treatment of Siewert II/III adenocarcinoma of the esophagogastric junction (AEG).

MATERIALS AND METHODS

Ninety-nine patients with Siewert type II/III AEG were enrolled and divided into two groups: the laparoscopic CME transhiatal approach (CEM-TH, n = 61) group and traditional laparoscopic transhiatal (TH, n = 38) group. Intraoperative and postoperative clinical data of both groups were analyzed.

RESULTS

The laparoscopic trasihiatal surgery was technically successful in all patients. The surgical time, intraoperative bleeding, and hospital stay were all significantly (P < 0.05) reduced in the CME-TH group compared with those in the TH group. The levels of white blood cells on postoperative day (POD) 1 and 5, postoperative CRP on POD 3 and 5, and postoperative PCT were significantly (P < 0.05) lower while lymph nodes were harvested significantly (P < 0.05) more in the CME-TH group than in the TH group. Complications were not significantly (P > 0.05) different between two groups. No death occurred within 90 days.

CONCLUSION

The CME theory could be safely and effectively applied laparoscopically to treat patients with Siewert II/III AEG. Mesogastrium and lower mesoesophagus can be completely resected together with the tumor, lymph nodes, adipose tissue, and blood vessels as an "intact package," leading to better short-term outcomes.

Short-term outcomes of D2 lymphadenectomy plus complete mesogastric excision for gastric cancer: a propensity score matching analysis

BACKGROUND

Our previous study has demonstrated the surgical advantages of D2 lymphadenectomy plus complete mesogastric excision (D2 + CME) in gastric cancer surgery. To further verify the safety of D2 + CME procedure, we conducted this large-scale, observational cohort study and applied propensity score matching (PSM) approach to compare D2 + CME with conventional D2 in terms of short-term outcomes in gastric cancer patients.

METHODS

Data on 855 patients from Tongji Hospital who underwent laparoscopic-assisted distal gastrectomy (LADG) with R0 resection (496 in the conventional D2 cohort and 359 in the D2 + CME cohort) between Dec 12, 2013 and Dec 28, 2017 were retrieved from prospectively maintained clinical database. After PSM analysis at a 1:1 ratio, each cohort included 219-matched patients. Short-term outcomes, including surgical results, morbidity, and mortality within 30 days after the operation, were collected and analyzed.

RESULTS

In this large-scale, observational cohort study based on PSM analysis, the D2 + CME procedure showed less intra-laparoscopic blood loss, more lymph node harvest, and faster postoperative flatus than the conventional D2 procedure. However, both the overall and severe postoperative adverse events (Clavien-Dindo classification grade ≥ III a) seemed comparable between two cohorts.

CONCLUSION

The present study showed that D2 + CME was associated with better short-term outcomes than conventional D2 dissection for patients with resectable gastric cancer.

D2 lymphadenectomy with complete mesogastrium excision vs. conventional D2 gastrectomy for advanced gastric cancer

Background:

The complete mesogastrium excision (CME) based on D2 radical gastrectomy is believed to significantly reduce the local-regional recurrence compared with D2 radical gastrectomy in advanced gastric cancer, and it is widely used in China. This study aimed to explore whether D2 + CME is superior to D2 on surgical outcomes during gastrectomy from Chinese data.

Methods:

Feasible studies comparing the D2 + CME (D2 + CME group) and D2 (D2 group) published up to March 2020 are searched from electronic databases. The data showing surgical and complication outcomes are extracted to be pooled and analyzed.

Results:

Fourteen records including 1352 patients were included. The D2 + CME group had a shorter mean operative time (weighted mean difference [WMD] = —16.72 min, 95% confidence interval [CI]: −26.56 to −6.87 min, P < 0.001), lower mean blood loss (WMD = −39.08 mL, 95% CI: −49.94 to −28.21 mL, P < 0.001), higher mean number of retrieved lymph nodes (WMD = 2.13, 95% CI: 0.58–3.67, P = 0.007), shorter time to first flatus (WMD = −0.31 d, 95% CI: −0.53 to − 0.10 d, P = 0.005), and postoperative hospital days (WMD = −1.09, 95% CI: −1.92 to −0.25, P = 0.010) than the D2 group. Subgroup analysis suggested that the advantages from the D2 + CME group were obvious in traditional open radical gastrectomy, proximal gastrectomy, and distal gastrectomy compared with D2 group. The evaluations of post-operative complications showed that the patients who underwent D2 + CME had a lower incidence of post-operative complications than the patients who underwent D2 surgery alone (relative risk [RR] = 0.65, 95% CI: 0.45–0.87, P = 0.003). The D2 radical gastrectomy plus CME improved 3-year overall survival (OS) (RR = 1.16, 95% CI: 1.02–1.32, P = 0.020) and lowered the local recurrence rate (RR = 0.51, 95% CI: 0.28–0.94, P = 0.030). The patients undergoing laparoscopic surgery or total gastrectomy had more significant advantages compared between D2 + CME and D2 groups in 3-year OS.

Conclusion:

The data from China show that D2 radical gastrectomy plus CME are reliable procedures and safety compared to D2 radical gastrectomy with faster recovery, lower risk, and better prognosis.

Complete Mesogastric Excisions Involving Anatomically Based Concepts and Embryological-Based Surgeries: Current Knowledge and Future Challenges

Surgeries for gastrointestinal tract malignancies are based on the paradigm that we should remove the tumour together with its lymphatic drainage in one block. This concept was initially proposed in rectal surgery and called a total mesorectal excision. This procedure gained much interest and has improved oncological results in rectal cancer surgery. The same idea for mesogastric and complete mesogastric excisions was proposed but, because of the complexity of the gastric mesentery, it has not become a standard technique. In this review, we analysed anatomical and embryological factors, proposed technical aspects of this operation and incorporated the available initial results of this concept. We also discussed analogies to other gastrointestinal organs, as well as challenges to this concept.

Complete mesogastric excision for locally advanced gastric cancer: short-term outcomes of a randomized clinical trial

Implementation of complete mesogastric excision in gastric cancer surgery, named D2 lymphadenectomy plus complete mesogastric excision (D2+CME), has recently been proposed as an optimal procedure. However, the safety and efficacy of D2+CME remain uncertain. In this randomized controlled trial, patients receiving D2+CME exhibit less intraoperative blood loss, more lymph node harvesting, and earlier postoperative flatus than patients receiving conventional D2 radical surgery. Univariate Cox regression analysis reveals that the risk ratio for postoperative flatus in D2+CME group is 1.247 (p = 0.044). Overall postoperative complications are comparable between the two groups, but complications are significantly less severe in the D2+CME group than the D2 group (Clavien-Dindo classification grade ≥ IIIa: 4 D2+CME patients [11.8%] versus 9 D2 patients [33.3%]; p = 0.041). In conclusion, our work shows that D2+CME is associated with better short-term outcomes and surgical safety than conventional D2 dissection for patients with advanced gastric cancer.

Gastric cancer patients receiving D2+CME exhibit less intraoperative blood loss

The number of lymph nodes harvested with D2+CME is significantly improved

D2+CME surgery could provide faster postoperative flatus

D2+CME is less likely to cause severe complications than conventional surgery

Global updates in the treatment of gastric cancer: a systematic review. Part 2: perioperative management, multimodal therapies, new technologies, standardization of the surgical treatment and educational aspects

Gastric cancer is the fifth malignancy and the third cause of cancer death worldwide, according to the global cancer statistics presented in 2018. Its definition and staging have been revised in the eight edition of the AJCC/TNM classification, which took effect in 2018. Novel molecular classifications for GC have been recently established and the process of translating these classifications into clinical practice is ongoing. The cornerstone of GC treatment is surgical, in a context of multimodal therapy. Surgical treatment is being standardized, and is evolving according to new anatomical concepts and to the recent technological developments. This is leading to a massive improvement in the use of mini-invasive techniques. Mini-invasive techniques aim to be equivalent to open surgery from an oncologic point of view, with better short-term outcomes. The persecution of better short-term outcomes also includes the optimization of the perioperative management, which is being implemented on large scale according to the enhanced recovery after surgery principles. In the era of precision medicine, multimodal treatment is also evolving. The long-time-awaited results of many trials investigating the role for preoperative and postoperative management have been published, changing the clinical practice. Novel investigations focused both on traditional chemotherapeutic regimens and targeted therapies are currently ongoing. Modern platforms increase the possibility for further standardization of the different treatments, promote the use of big data and open new possibilities for surgical learning. This systematic review in two parts assesses all the current updates in GC treatment.

An Optimal Surgical Approach for Suprapancreatic Area Dissection in Laparoscopic D2 Gastrectomy with Complete Mesogastric Excision

BACKGROUND

During the radical operation, the suprapancreatic area is featured by anatomical complexity, and the lymph node dissection for this area is technically difficult and demanding.^1-4 Previously, we have demonstrated the presence of disseminated cancer cells in the mesogastrium^5,6 and presented a mesogastrium model for gastrectomy.⁷ As a consequence, laparoscopic D2 lymphadenectomy plus complete mesogastric excision (D2+CME) was proposed as a new concept in the surgical treatment of advanced gastric cancer.⁸ D2+CME procedure has been shown to be associated to lower number of free intraperitoneal cancer cells and with a better disease-free survival than conventional D2 gastrectomy.⁹ Under the concept of mesogastrium model, the proposed D2+CME procedure could help surgeons better define the anatomical boundaries of suprapancreatic mesogastrium, thus using it to achieve a complete and standard excision of the suprapancreatic area dissection. Here, we briefly present perioperative results of our case series with the laparoscopic curative subtotal gastrectomy and D2+CME with a R0 resection and present a video to detail the technical aspects of a laparoscopic D2+CME approach for suprapancreatic area dissection.

METHODS

All patients in this study underwent laparoscopic subtotal gastrectomy (D2+CME) with a curative R0 resection. This study was approved by the Tongji Hospital Ethics Committee (Unique Reference Number: TJ-IRB20180811). The procedures in the video are described as follows. Based on our previous mesogastrium model (also named "Table model", Supplemental Figure 1), the suprapancreatic mesogastrium is attached to the lesser curvature or the posterior gastric wall and extended to the suprapancreatic area, respectively.⁷ Surgeon stands on patient left side, and the assistant lifts the stomach upward and cephalic to expose the suprapancreatic mesogastrium including left gastric mesentery (LGM), right gastric mesentery (RGM) and posterior gastric mesentery (PGM). First of all, towards to the left side of the suprapancreatic area, the "tri-junction" point of LGM is exposed. Using an energy devise, surgeon opens serosa layer and identifies the retrogastric space. The LGM and PGM are mobilized bluntly, between which a fusion retrogastric space is revealed. Both the LGM and PGM are covered by smooth and shiny surfaces of fascial propria and regarded as the "meso-bed" mutually. Secondly, at the inner side of duodenum, surgeon bluntly separates the adjuvant tissues along gastro-duodenal artery (GDA) upward and exposes right gastric mesentery (RGM). Next, after mobilizing the left gastric mesentery, surgeon removes the adipose tissue adherent to the common hepatic artery (CHA) and exposes the root of the left gastric artery after dissecting the perivascular sheath with triple-clips. Then, surgeon dissects RGM along the CHA and portal vein (HPV) towards the right side of the suprapancreatic area; afterwards, the right gastric vessels and RGM are identified and ligated. Lastly, the superior border of splenic vessels is dissected. The anterior lobe of the PGM is raised up with ligated posterior gastric vessels. Remarkably, posterior gastric vessels may be absent in some cases. Reconstruction of the alimentary tract is Roux-en-Y method. Standard recovery protocols are followed in postoperative treatments.

RESULTS

Between August 28th 2017 and December 27th 2018, 107 patients receiving laparoscopic curative subtotal gastrectomy (D2+CME) with a R0 resection were retrospective collected in this study. After exposing the suprapancreatic mesogastrium including RGM, PGM and LGM with D2+CME procedure, the LNs and fat tissues around 7, 9, 8a, 12a and 11p were removed en bloc in all patients. This study recruited 67 males and 40 females. The median age was 55 years, with body mass index (BMI) 23.0 kg/m² (Supplemental Table 1). The median number of retrieved regional lymph nodes was 31 (range 25-41), including 22 (range 17-27.5) suprapancreatic lymph nodes. The median volume of blood loss was 14 ml (range 6-34). The median total operation time was 287 min (range 265.5-313.5) and laparoscopic surgery time was 132 min (range 116-142) (Supplemental Table 2). Postoperative morbidity occurred at a rate of 9.3 %, and the mortality rate was 0% (Supplemental Table 3). The median follow-up was 10 months (range 8-13). No patient was lost during follow-up (Supplemental Table 4).

CONCLUSION

A laparoscopic subtotal gastrectomy with D2+CME procedure provides for a complete and standardized en bloc excision of the suprapancreatic area dissection.

Global updates in the treatment of gastric cancer: a systematic review. Part 1: staging, classification and surgical treatment

Gastric cancer (GC) is the fifth malignancy and the third cause of cancer death worldwide, according to the global cancer statistics presented in 2018. Its definition and staging have been revised in the eight edition of the AJCC/TNM classification, which took effect in 2018. Novel molecular classifications for GC have been recently established and the process of translating these classifications into clinical practice is ongoing. The cornerstone of GC treatment is surgical, in a context of multimodal therapy. Surgical treatment is being standardized, and is evolving according to new anatomical concepts and to the recent technological developments. This is leading to a massive improvement in the use of mini-invasive techniques. Mini-invasive techniques aim to be equivalent to open surgery from an oncologic point of view, with better short-term outcomes. The persecution of better short-term outcomes also includes the optimization of the perioperative management, which is being implemented on large scale according to the enhanced recovery after surgery principles. In the era of precision medicine, multimodal treatment is also evolving. The long-time-awaited results of many trials investigating the role for preoperative and postoperative management have been published, changing the clinical practice. Novel investigations focused both on traditional chemotherapeutic regimens and targeted therapies are currently ongoing. Modern platforms increase the possibility for further standardization of the different treatments, promote the use of big data, and open new possibilities for surgical learning. This systematic review in two parts assesses all the current updates in GC treatment.

Laparoscopic perigastric mesogastrium excision technique for radical total gastrectomy

Introduction

Complete mesogastrium excision (CME) of the perigastric mesogastrium and dissection of lymph nodes (LNs) no. 10 and no. 11 remain technically challenging aspects of laparoscopic radical total gastrectomy (LRTG) plus CME. To address some of these difficulties, we introduced the laparoscopic perigastric mesogastrium excision technique (LPMET) and the concept of the “enjoyable space” to partly modify the procedures of conventional radical surgery and characterize the perigastric space and the surgical plane as well as its boundaries.

Aim

To introduce the laparoscopic perigastric mesogastrium excision technique (LPMET) and the “enjoyable space” when undergoing laparoscopic radical total gastrectomy.

Material and methods

From July 2016 to June 2017, 79 cases of upper gastric cancer that were treated by laparoscopic D2 gastrectomy plus CME were investigated. The retrospective database included the patient characteristics, intraoperative and postoperative outcomes, and morbidity and mortality rates depending on the completeness of their medical records.

Results

Laparoscopic D2 gastrectomy plus CME was successfully performed in all 79 cases. The mean surgical time was 232.5 ±46.0 min, and the intraoperative blood loss was 67.6 ±52.3 ml. A total of 2245 LNs were retrieved (mean 28.1 ±10.8 retrieved from each specimen). The mean postoperative hospital stay was 10.3 ±1.6 days. The postoperative morbidity rate was 17.7%. After a median follow-up period of 12 months, one patient experienced liver metastasis; of the other 78 patients, none died or experienced tumor recurrence or metastasis.

Conclusions

Laparoscopic perigastric mesogastrium excision technique and the “enjoyable space” could be a novel, minimally invasive approach and space to achieve CME and provide benefit for the dissection of LNs no. 10 and no. 11.

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.

Detection of carcinoembryonic antigen in peritoneal fluid of patients undergoing laparoscopic distal gastrectomy with complete mesogastric excision

Background

Surgery for gastric cancer may result in free intraperitoneal cancer cells. This study aimed to determine whether laparoscopic gastrectomy with complete mesogastric excision (D2 + CME) reduces the number of free intraperitoneal cancer cells.

Methods

Patients with gastric cancer who had a conventional D2 or D2 + CME laparoscopic distal gastrectomy between April 2015 and February 2017 were included in the study. Intraoperative peritoneal washings were collected before and after tumour resection. Reverse transcriptase–quantitative real-time PCR for carcinoembryonic antigen (CEA) was used to assess the presence of gastric cancer cells.

Results

Eighty-five patients underwent conventional D2 lymphadenectomy and 76 had the D2 + CME procedure. Of 161 peritoneal fluid samples obtained before gastrectomy, 137 (D2, 72; D2 + CME, 65) had low CEA expression indicative of no cancer cells. After gastrectomy, high CEA expression was detected in 23 of the 72 samples (32 per cent) from patients in the D2 group, and in ten of the 65 samples (15 per cent) from the D2 + CME group. In the overall cohort, mean CEA expression level after gastrectomy was lower in the D2 + CME group than in the D2 group (P = 0·0038). In patients with low CEA expression before gastrectomy, disease-free survival in the D2 + CME group was better than that in the D2 group (P = 0·033).

Conclusion

Laparoscopic distal gastrectomy with complete mesogastric excision reduces the number of free intraperitoneal cancer cells and is associated with a better disease-free survival than conventional D2 gastrectomy.

The length and complexity of mesentery are related to the locoregional recurrence of the carcinoma in gut

Local-regional relapse is the main recurrence pattern of the carcinoma in gut, and leads to poor prognosis. With the development of the total mesorectal and complete mesocolic excision (TME/CME), the local relapse rate of colorectal cancer has significantly decreased. People attributed it to the improvement of lymphadenectomy, but lymphatic metastasis is difficult to explain the local relapse in N0 patients. Previously, we have proven the existence of "Metastasis V" in mesogastrium and mesocolorectum, and supposed that it is one of the major risk factors in local recurrence. Therefore, we think complete mesentery excision can effectively reduce "Metastasis V", prevent cancer leak and improve patients' outcome. Due to the different length and complexity of mesentery, the difficulty of mesentery excision varies. Meanwhile, there is an obvious distinction of local relapse rate in different alimentary tract, even in different segment of a same organ. Thus we assume that the length and complexity of mesentery may be a risk factor of the locoregional recurrence of the carcinoma in gut.

Short-term outcomes of laparoscopic D2 lymphadenectomy with complete mesogastrium excision for advanced gastric cancer

BACKGROUND

D2 lymphadenectomy has been widely accepted as a standard procedure of surgical treatment for local advanced gastric cancer [1, 2]. However, neither the dissection boundary nor the extent of the excision for perigastric soft tissues has been described [3-7]. Our previous researches demonstrate the existence of disseminated cancer cells in the mesogastrium [8, 9] and present an understandable mesogastrium model for gastrectomy [10]. Hence, the D2 lymphadenectomy plus complete mesogastrium excision (D2 + CME) is firstly proposed in this study, aiming to assess the safety, feasibility and corresponding short-term surgical outcomes.

METHODS

All of these patients underwent laparoscopy assisted D2 + CME radical gastrectomy with a curative R0 resection, and all the operations were performed by Prof. Jianping Gong, chief of GI surgery of Tongji Hospital, Huazhong University of Science and Technology. All participants provided informed written consent to participate in the study. This study was approved by the Tongji Hospital Ethics Committee. The standard surgical procedures in the video are described as follows. Dissect along the gastrocolic ligament and then toward the left colic flexture with special made gauze. Bluntly separate the adipose tissues to find fascia plane. Expose along the plane toward the splenic inferior polar area. Precede to the origins of left gastroepiploic vessels (LGEVs), clip and cut. All the mobilized adipose tissues in this area are defined as left gastroepiploic mesentery (LGEM) [10]. Next, turn to infra-pyloric area. Dissect the fascia plane between right gastroepiploic mesentery (RGEM) and transverse mesocolon. Turn to the pancreas head, remove the covering adipose tissues, identify the superior mesentery vein and expose the origins of right gastroepiploic vessels (RGEVs). Clip and cut. All the surrounding mobilized adipose tissues are defined as RGEM [10]. Move to the superior boarder of pancreas with the stomach reflected cephalad, incise the serosa and bluntly mobilize through the plane with gauze. Turn to the common hepatic artery (CHA), remove the adherent adipose tissue. Expose the root of left gastric vein, clip and cut. Dissect the thick sheath of left gastric artery, expose at the root, trip clip and cut. All mobilized lateral adipose tissues and dorsal parts are defined as left gastric mesentery (LGM) [10]. Toward right, dissect follow the CHA and hepatic portal vein (HPV). Next, move toward the left side of LGM and dissect along the splenic artery until reaching the posterior gastric wall. Move to the anterior area of stomach and divide the lesser omentum. Clean up the adipose tissue and nerves along the lesser curvature up to the gastroesophageal junction. Expose and cut the right gastric vessels (RGVs) where the mobilized adipose tissues are defined as right gastric mesentery (RGM) [10]. Reconstruction of the alimentary tract was done by extracorporeal anastomosis. Standard recovery protocols were followed in postoperative treatments.

RESULTS

Fifty-four patients between September 2014 and March 2015 have been recruited with informed consent and underwent laparoscopic D2 + CME by a single surgeon. The mean number of retrieved regional lymph nodes was 35.04 ± 10.70 (range 14-55). The mean volume of blood loss was 12.44 ± 22.89 ml (range 5-100). The mean laparoscopic surgery time was 127.82 ± 17.63 min (range 110-165). The mean hospitalization time was 11.09 ± 4.28 days (range 8-28). No operative complication was observed during the hospitalization.

CONCLUSION

The anatomical boundary of mesogastrium is well described and dissected within D2 + CME surgical process. It proves to be safely feasible and repeatable with less blood lost, qualified lymph nodes retrieval results and other improved short-term surgical outcomes in advanced gastric cancer. Meanwhile, potential disseminated cancer cells fall into the mesogastrium can be eradicated by D2 + CME.