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

Current trends in the management of Gastro-oEsophageal cancers: Updates to the ESSO core curriculum (ESSO-ETC-UGI-WG initiative)

Gastro-oEsophageal Cancers (GECs) are severe diseases whose management is rapidly evolving. The European Society of Surgical Oncology (ESSO) is committed to the generation and spread of knowledge, and promotes the multidisciplinary management of cancer patients through its core curriculum. The present work discusses the approach to GECs, including the management of oligometastatic oesophagogastric cancers (OMEC), the diagnosis and management of peritoneal metastases from gastric cancer (GC), the management of Siewert Type II tumors, the importance of mesogastric excision, the role of robotic surgery, textbook outcomes, organ preserving options, the use of molecular markers and immune check-point inhibitors in the management of patients with GECs, as well as the improvement of current clinical practice guidelines for the management of patients with GECs. The aim of the present review is to provide a concise overview of the state-of-the-art on the management of patients with GECs and, at the same time, to share the latest advancements in the field and to foster the debate between surgical oncologists treating GECs worldwide. We are sure that our work will, at the same time, give an update to the advanced surgical oncologists and help the training surgical oncologists to settle down the foundations for their future practice.

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.

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.

The short- and long-term effect of membrane anatomy-guided laparoscopic D2 lymphadenectomy plus regional complete mesogastrium excision for locally advanced gastric cancer

OBJECTIVE

Retrospectively analyzed the short- and long-term efficacy between laparoscopic D2 lymphadenectomy plus regional complete mesogastrium excision (D2 + rCME) and traditional laparoscopic D2 in the treatment of patients with locally advanced gastric cancer (LAGC), in order to obtain more evidence for D2 + rCME gastrectomy.

METHODS

A total of 599 LAGC patients who underwent laparoscopy-assisted radical gastrectomy from January 2014 to December 2019, including 367 cases in the D2 + rCME group and 232 cases in the D2 group. Intraoperative and postoperative clinicopathological parameters, postoperative complications and long-term survival in the two groups were statistically analyzed.

RESULTS

No significant differences in the positive rate of mesogastric tumor deposits, the number of positive lymph nodes and postoperative length of stay were found between the two groups (P > 0.05). In the D2 + rCME group, intraoperative blood loss was significantly reduced (84.20 ± 57.64 ml vs. 148.47 ± 76.97 ml, P < 0.001), the time to first postoperative flatus and first liquid diet intake were significantly shortened (3[2-3] days vs. 3[3-3] days, P < 0.001; 7[7-8] days vs. 8[7-8] days, P < 0.001), and the number of lymph nodes dissected was greater (43.57 ± 16.52 pieces vs. 36.72 ± 13.83 pieces, P < 0.001). The incidence of complications did not significantly differ between the D2 + rCME group (20.7%) and D2 group (19.4%) (P > 0.05). Although there was no statistically difference in 3-year OS and DFS between the two groups. However, the trend was better in D2 + rCME group. In subgroup analysis, patients with positive tumor deposits (TDs) in the D2 + rCME group had significantly better 3-year DFS compared With D2 group (P < 0.05).

CONCLUSION

Laparoscopic D2 + rCME is safe and feasible for the treatment of LAGC and is characterized by less bleeding, greater lymph node dissection and rapid recovery, without increasing postoperative complications. D2 + rCME group showed a better trend of long-term efficacy, especially significant beneficial for LAGC patients who with positive TDs.

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.

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.

Novel Biomarkers of Gastric Adenocarcinoma: Current Research and Future Perspectives

Simple Summary

Gastric cancer is characterized by poor survival rates despite surgery and chemotherapy. Current research focuses on biomarkers to improve diagnosis and prognosis, and to enable targeted treatment strategies. The aim of our review was to give an overview over the wide range of novel biomarkers in gastric cancer. These biomarkers are targets of a specific treatment, such as antibodies against human epidermal growth factor receptor 2. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are vascular endothelial growth factor, programmed cell death protein 1, and Claudin 18.2. There is a vast number of biomarkers based on DNA, RNA, and protein expression, as well as detection of circulating tumor cells and the immune tumor microenvironment.

Abstract

Overall survival of gastric cancer remains low, as patients are often diagnosed with advanced stage disease. In this review, we give an overview of current research on biomarkers in gastric cancer and their implementation in treatment strategies. The HER2-targeting trastuzumab is the first molecular targeted agent approved for gastric cancer treatment. Other promising biomarkers for targeted therapies that have shown relevance in clinical trials are VEGF and Claudin 18.2. Expression of MET has been shown to be a negative prognostic factor in gastric cancer. Targeting the PD-1/PD-L1 pathway with immune checkpoint inhibitors has proven efficacy in advanced gastric cancer. Recent technology advances allow the detection of circulating tumor cells that may be used as diagnostic and prognostic indicators and for therapy monitoring in gastric cancer patients. Prognostic molecular subtypes of gastric cancer have been identified using genomic data. In addition, transcriptome profiling has allowed a comprehensive characterization of the immune and stromal microenvironment in gastric cancer and development of novel risk scores. These prognostic and predictive markers highlight the rapidly evolving field of research in gastric cancer, promising improved treatment stratification and identification of molecular targets for individualized treatment in gastric cancer.

Peripheral Lymphocyte Subsets Absolute Counts as Feasible Clinical Markers for Predicting Surgical Outcome in Gastric Cancer Patients After Laparoscopic D2 Gastrectomy: A Prospective Cohort Study

Background

Immune function influenced patients’ recovery from major abdominal surgery. The aim of this study is to explore the clinical feasibility of peripheral lymphocyte absolute counts for predicting short-term surgical outcomes in gastric cancer patients after laparoscopic D2 gastrectomy.

Methods

This is a prospective cohort study from a single tertiary referral hospital. Patients diagnosed with gastric cancer who met the inclusion criteria were included in this study. We collected the demographic and clinicopathological characteristics of included patients. We monitored perioperative dynamics of absolute counts of peripheral lymphocyte subsets. Predictive factors for length of postoperative hospital stay and complications were investigated in univariate and multivariate analyses.

Results

A total of 137 gastric cancer patients were included. Decreased preoperative absolute counts of peripheral lymphocyte subsets were correlated with advanced clinical stage. In multivariate analysis, independent predictive factors for prolonged hospital stay were age (p=0.04), decreased preoperative B cell counts (p=0.05), decreased preoperative NK cell counts (p=0.05) and complications (p<0.01). For postoperative complication, independent predictive factors were age (p=0.02), operation time (p=0.05), lymphocyte to C-reactive protein ratio (p=0.01) and decreased preoperative B cell counts (p=0.01).

Conclusion

Our findings for the first time revealed that absolute counts of peripheral lymphocyte subsets are independent predictive factors for surgical outcomes in gastric cancer patients after D2 gastrectomy. We suggested that patients with impaired immune state should receive both preoperative immune modulator and nutritional support.

Clinical importance of carcinoembryonic antigen messenger RNA level in peritoneal lavage fluids measured by transcription-reverse transcription concerted reaction for advanced gastric cancer in laparoscopic surgery

BACKGROUND

Transcription-reverse transcription concerted reaction (TRC) is recognized as a useful method for detecting free cancer cells in the peritoneal cavity and predicting peritoneal recurrence in patients with gastric cancer. Nonetheless, the clinical significance of TRC in laparoscopic surgery remains unclear. This study aimed to evaluate the clinical importance of carcinoembryonic antigen (CEA) messenger RNA (mRNA) level in peritoneal lavage fluids measured by TRC in laparoscopic surgery for locally advanced gastric cancer.

METHODS

We enrolled patients with locally advanced gastric cancer who underwent laparoscopic gastrectomy. Peritoneal lavage fluids were collected prior to gastrectomy, and the TRC method was employed to quantify CEA mRNA in peritoneal washes. Overall survival (OS), recurrence-free survival (RFS), and peritoneal recurrence-free survival (PRFS) were analyzed using the Kaplan-Meier method and compared using the log-rank test. Adjusted Cox proportional hazards regression models were used to calculate the hazard ratios (HRs) for CEA mRNA positivity.

RESULTS

A total of 100 patients were analyzed in this study. Overall, 22 patients (22%) exhibited CEA mRNA positivity in peritoneal lavage fluids, as measured by TRC. No significant association between CEA mRNA levels and clinicopathological characteristics was observed. Patients who were CEA mRNA-positive in peritoneal lavage fluids had significantly worse OS, RFS, and PRFS than those who were CEA mRNA-negative (p = 0.0059, p < 0.0001, and p = 0.0022, respectively). In the univariate Cox model, the HR for all-cause mortality in CEA mRNA-positive versus CEA mRNA-negative patients was 3.60 (95% CI, 1.33-9.55; p = 0.0129). Multivariate analysis revealed that CEA mRNA positivity was a significant independent factor for recurrence.

CONCLUSIONS

TRC enables the detection of free cancer cells in the peritoneal cavity and CEA mRNA levels can help predict the prognosis, even in laparoscopic gastrectomy.

Effects of Laparoscopic Radical Gastrectomy on Peritoneal Micrometastases of Gastric Cancer

BACKGROUND

Some reports asserted that the stimulation of ultrasonic scalpel and the persistent state of carbon dioxide (CO2) pneumoperitoneum in laparoscopic surgery may affect the adhesion and invasion of gastric cancer (GC) cells. This study aimed to reveal the effects of laparoscopic radical gastrectomy on peritoneal micrometastases (PM) of GC.

MATERIALS AND METHODS

Fifty-three patients who underwent laparoscopic radical gastrectomy for GC were enrolled in the study. The expressions of carcinoembryonic antigen (CEA) mRNA and dopa decarboxylase (DDC) mRNA in peritoneal lavage fluid were detected by reverse transcription-polymerase chain reaction. The positive rates of CEA mRNA and DDC mRNA in preoperative peritoneal lavage fluid (pre-CEA, pre-DDC) were compared with those in postoperative lavage fluid (post-CEA, post-DDC). The correlation between the expressions of pre-CEA and pre-DDC and clinicopathologic factors and disease-free survival was analyzed.

RESULTS

There was no significant difference in the positive rates of pre-CEA and pre-DDC compared with those of post-CEA and post-DDC (all P>0.05). The positive rates of pre-CEA and pre-DDC increased with the increase of TNM stage, deepening of invasion, lymph node metastasis, and serosal invasion (all P<0.05), but had no correlation with tumor location, size, degree of differentiation, nerve invasion, and vascular invasion (all P>0.05). The disease-free survival in the combined positive patients was lower than that in the negative patients.

CONCLUSIONS

Laparoscopic radical gastrectomy for GC is safe and feasible, without increasing the risk of PM. The PM of GC may be associated with late tumor stage, deep infiltration, lymph node metastasis, and serosal invasion.

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

Gastric equivalent of the 'Holy Plane' to standardize the surgical concept of stomach cancer to mesogastric excision: updating Jamieson and Dobson's historic schema

BACKGROUND

Surgery for curable gastric cancer has historically involved dissection of lymph nodes, depending on the risk of metastasis. By establishing the concept of mesogastric excision (MGE), we aim to make this approach compatible with that for colorectal cancer, where the standard is excision of the mesentery.

METHODS

Current advances in molecular embryology, visceral anatomy, and surgical techniques were integrated to update Jamieson and Dobson's schema, a historical reference for the mesogastrium.

RESULTS

The mesogastrium develops with a three-dimensional movement, involving multiple fusions with surrounding structures (retroperitoneum or other mesenteries) and imbedding parenchymal organs (pancreas, liver, and spleen) that grow within the mesentery. Meanwhile, the fusion fascia and the investing fascia interface with adjacent structures of different embryological origin, which we consider to be equivalent to the 'Holy Plane' in rectal surgery emphasized by Heald in the concept of total mesorectal excision. Dissecting these fasciae allows for oncologic MGE, consisting of removing lymph node-containing mesenteric adipose tissue with an intact fascial package. MGE is theoretically compatible with its colorectal counterpart, although complete removal of the mesogastrium is not possible due to the need to spare imbedded vital organs. The celiac axis is treated as the central artery of the mesogastrium, but is peripherally ligated by tributaries flowing into the stomach to feed the spared organs.

CONCLUSION

The obscure contour of the mesogastrium can be clarified by thinking of it as the gastric equivalent of the 'Holy Plane'. MGE could be a standard concept for surgical treatment of stomach cancer.

Distribution of Metastatic Cancer Cells in Colorectal Mesentery

BACKGROUND

To investigate the distribution of metastatic cancer cells in the mesentery (referred to as metastasis V) and enrich the understanding of the metastasis of colorectal cancer.

METHODS

A total of two hundred ninety-nine patients who received colorectal operations at the Department of Gastrointestinal Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology between April 2018 and December 2018 were included. Samples were acquired from the dissected mesentery after the operation, and hematoxylin-eosin staining or immunohistochemistry was used to detect metastatic cancer cells. Pathological factors, including tumor position, tumor size, invasion depth, tumor differentiation, lymph node involvement, local vessel invasion, and perineural invasion, were recorded.

RESULTS

Metastatic cancer cells in the colorectal mesentery (metastasis V) were detected in 62 of 299 patients. Metastasis V was closely correlated with tumor invasion depth, lymph node metastasis, tumor differentiation, and perineural and vessel invasion by cancer cells. Metastasis V occurred more frequently in patients with T3 stage (26.27%) and T4 stage (40.00%) than in patients with T1 and T2 stages (0% and 2%, respectively). Metastasis V was frequently detected in patients with N2a and N2b stage tumors (51.72% and 61.54%, respectively). Metastasis V was more frequently detected in patients with perineural metastasis and local vessel invasion. In addition, metastasis V incidences in colon and rectal cancer were similar.

CONCLUSION

The incidence rate of metastasis V is correlated with tumor staging factors and occurs more frequently in advanced-stage patients.

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.

Novel Graphene Biosensor Based on the Functionalization of Multifunctional Nano-bovine Serum Albumin for the Highly Sensitive Detection of Cancer Biomarkers

A simple, convenient, and highly sensitive bio-interface for graphene field-effect transistors (GFETs) based on multifunctional nano-denatured bovine serum albumin (nano-dBSA) functionalization was developed to target cancer biomarkers. The novel graphene-protein bioelectronic interface was constructed by heating to denature native BSA on the graphene substrate surface. The formed nano-dBSA film served as the cross-linker to immobilize monoclonal antibody against carcinoembryonic antigen (anti-CEA mAb) on the graphene channel activated by EDC and Sulfo-NHS. The nano-dBSA film worked as a self-protecting layer of graphene to prevent surface contamination by lithographic processing. The improved GFET biosensor exhibited good specificity and high sensitivity toward the target at an ultralow concentration of 337.58 fg mL^-1. The electrical detection of the binding of CEA followed the Hill model for ligand-receptor interaction, indicating the negative binding cooperativity between CEA and anti-CEA mAb with a dissociation constant of 6.82 × 10^-10 M. The multifunctional nano-dBSA functionalization can confer a new function to graphene-like 2D nanomaterials and provide a promising bio-functionalization method for clinical application in biosensing, nanomedicine, and drug delivery.