Local resection of the stomach for gastric cancer

Research progress of minimally invasive surgery for gastric cancer

Since the first laparoscopic radical surgery for early gastric cancer 30 years ago, there has been a gradual shift from "open" to "minimally invasive" surgery for gastric cancer. This transition is due to advancements in refined anatomy, enlarged field of view, faster recovery, and comparable oncological outcomes. Several high-quality clinical studies have demonstrated the safety and effectiveness of laparoscopy in the treatment of both early and locally advanced gastric cancer. The role of perioperative chemotherapy in managing locally advanced gastric cancer has been widely recognized, and there have been continuous breakthroughs in the exploration of targeted therapy and immunotherapy for perioperative treatment. Additionally, the application of indocyanine green near-infrared imaging technology, 3D laparoscopic technology, and robotic surgery systems has further improved the accuracy and minimally invasive nature of gastric cancer surgeries. Looking ahead, the field of minimally invasive surgery for gastric cancer is expected to become more standardized, resulting in a significant enhancement in the quality of life for gastric cancer patients.

Laparoscopic and endoscopic cooperative surgery for full-thickness resection and sentinel node dissection for early gastric cancer

The endoscopic submucosal dissection (ESD) technique has become the gold standard for submucosal tumors that have negligible risk of lymph node metastasis (LNM), due to its minimal invasiveness and ability to improve quality of life. However, this technique is limited in stage T1 cancers that have a low risk of LNM. Endoscopic full thickness resection can be achieved with laparoscopic endoscopic cooperative surgery (LECS), which combines laparoscopic gastric wall resection and ESD. In LECS, the surgical margins from the tumor are clearly achieved while performing organ-preserving surgery. To overcome the limitation of classical LECS, namely the opening of the gastric wall during the procedure, which increases the risk of peritoneal tumor seeding, non-exposed endoscopic wall-inversion surgery was developed. With this full-thickness resection technique, contact between the intra-abdominal space and the intragastric space was eliminated.

Construction and validation of gastric cancer diagnosis model based on machine learning

Aim: To screen differentially expressed genes related to gastric cancer based on The Cancer Genome Atlas (TCGA) database and construct a gastric cancer diagnosis model by machine learning. Methods: Transcriptional data, genomic data, and clinical information of gastric cancer tissues and non-gastric cancer tissues were downloaded from the TCGA database, and differentially expressed genes of gastric cancer messenger RNA (mRNA) and long non-coding RNA (lncRNA) were screened out. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyzed the differentially expressed genes, and the protein-protein interaction (PPI) of differentially expressed genes was constructed. Core differentially expressed genes were screened by Cytoscape software’s molecular complex detection (MCODE) plug-in. The differential genes of lncRNA were analyzed by univariate Cox regression analysis and lasso regression for further dimension reduction to obtain the core genes. The core genes were screened by machine learning to construct the gastric cancer diagnosis model. The efficiency of the gastric cancer diagnosis model was verified externally by the Gene Expression Omnibus (GEO) database. Results: Finally, 10 genes including long intergenic non-protein coding RNA 1821 (LINC01821), AL138826.1, AC022164.1, adhesion G protein-coupled receptor D1-antisense RNA 1 (ADGRD1-AS1), cyclin B1 (CCNB1), kinesin family member 11 (KIF11), Aurora kinase B (AURKB), cyclin dependent kinase 1 (CDK1), nucleolar and spindle associated protein 1 (NUSAP1), and TTK protein kinase (TTK) were screened as gastric cancer diagnostic model genes. After efficiency analysis, it was found that the random forest algorithm model had the best comprehensive evaluation, with an accuracy of 92% and an area under the curve (AUC) of 0.9722, which was more suitable for building a gastric cancer diagnosis model. The GSE54129 data set was used to verify the gastric cancer diagnosis model with an AUC of 0.904, indicating that the gastric cancer diagnosis model had high accuracy. Conclusions: Machine learning can simplify the bioinformatics analysis process and improve efficiency. The core gene discovered in this study is expected to become a gene chip for the diagnosis of gastric cancer.

Circ_0004104 Accelerates the Progression of Gastric Cancer by Regulating the miR-539-3p/RNF2 Axis

BACKGROUND

Circular RNA (circRNA) has been shown to be closely associated with cancer progression, including gastric cancer (GC). However, the function of circ_0004104 in GC progression has not been clarified.

AIMS

The purpose of this study was to explore the role of circ_0004104 in GC progression.

METHODS

The expression levels of circ_0004104, miR-539-3p, and ring finger protein 2 (RNF2) were assessed using quantitative real-time polymerase chain reaction. Cell proliferation was measured by 3-(4,5-dimethyl-2 thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay, and cell migration and invasion were detected using transwell assay. The levels of glutamine, glutamate, and α-ketoglutarate were determined to evaluate the glutaminolysis of cells, and the protein levels of glutaminolysis-related markers and RNF2 were detected using western blot analysis. Furthermore, Dual-Luciferase Reporter Assay was employed to assess the interaction between miR-539-3p and circ_0004104 or RNF2. Animal experiments were carried out to evaluate the effect of circ_0004104 silencing on GC tumor growth in vivo.

RESULTS

Circ_0004104 was upregulated in GC, and its knockdown repressed the proliferation, metastasis, and glutaminolysis of GC cells in vitro and reduced GC tumor growth in vivo. Furthermore, we discovered that circ_0004104 could sponge miR-539-3p and miR-539-3p could target RNF2. The rescue experiments suggested that miR-539-3p inhibitor could reverse the suppressive effect of circ_0004104 silencing on GC progression, and RNF2 overexpression also reversed the inhibition effect of miR-539-3p mimic on GC progression.

CONCLUSION

Circ_0004104 accelerated GC progression via regulating the miR-539-3p/RNF2 axis, indicating that circ_0004104 might be a potential therapeutic target for GC.

Laparoscopic and endoscopic cooperative surgery for advanced gastric cancer as palliative surgery in elderly patients: a case report

Background

The number of elderly patients with gastric cancer is increasing, with the very elderly often refusing radical gastrectomy with lymph node dissection. Such a patient presented to us and we proposed a palliative surgery involving gastric local resection using laparoscopy endoscopy cooperative surgery (LECS).

Case presentation

An 89-year-old woman presented to our hospital with progressing anemia. She had an aortic arch replacement for aortic dissection 6 months previously and was taking antithrombotic drugs for atrial fibrillation. She was diagnosed with advanced gastric cancer, and we presented a radical resection treatment plan involving distal gastrectomy with lymph node dissection. However, she strongly refused undergoing radical gastric cancer resection. We believed that at least local control of the tumor could be effective in preventing future bleeding or stenosis due to tumor progression. Therefore, we proposed a local gastrectomy with LECS as an optional treatment, and she agreed to this treatment. The surgery was performed with minimal blood loss, and no postoperative complications were observed. Histopathological examination revealed a 45 × 31-mm, Type 2, poorly differentiated adenocarcinoma (pT4a, ly0, v1a), and the resected margin was negative. The patient was alive 2 years after surgery without apparent recurrence or other illness. In addition, her weight was maintained, together with her daily activity.

Conclusion

Local resection of gastric cancer with LECS might be an option for the palliative treatment of patients who refuse radical resection of gastric cancer.

The Incidence and Risk Factors for Metachronous Gastric Cancer in the Remnant Stomach after Gastric Cancer Surgery

Background/Aims

Less invasive surgical treatment is performed in East Asia to preserve postoperative digestive function and reduce complications such as postgastrectomy syndromes, but there is an issue of metachronous gastric cancer (GC) in the remaining stomach. This study aimed to analyze the incidence of metachronous GC and its risk factors in patients who had undergone partial gastrectomy.

Methods

A total of 3,045 GC patients who had undergone curative gastric partial resection at Seoul National University Bundang Hospital were enrolled and analyzed retrospectively for risk factors, including age, sex, smoking, alcohol, Helicobacterpylori status, family history of GC, histological type, and surgical method.

Results

Metachronous GC in the remaining stomach occurred in 35 of the 3,045 patients (1.1%) 23 in the distal gastrectomy group (18 with Billroth-I anastomosis, five with Billroth-II anastomosis), seven in the proximal gastrectomy (PG) group, and five in the pylorus-preserving gastrectomy (PPG) group. Univariate and multivariate Cox regression analyses showed that age ≥60 years (p=0.005) and surgical method used (PG or PPG, p<0.001) were related risk factors for metachronous GC, while male sex and intestinal type histology were potential risk factors.

Conclusions

Metachronous GC was shown to be related to older age and the surgical method used (PG or PPG). Regular and careful follow-up with endoscopy should be performed in the case of gastric partial resection, especially in patients with male sex and intestinal type histology as well as those aged ≥60 years undergoing the PG or PPG surgical method.

The incidences of metachronous multiple gastric cancer after various types of gastrectomy: analysis of data from a nationwide Japanese survey

BACKGROUND

The incidence of metachronous multiple gastric cancer (MMGC) after gastrectomy remains unclear. This study evaluated the incidences of MMGC according to specific gastrectomy types, including pylorus-preserving gastrectomy (PPG), proximal gastrectomy (PG), and function-preserving gastrectomy (FPG), which was categorized as segmental gastrectomy and local resection.

METHODS

We conducted a questionnaire survey of the Japanese Society for Gastro-Surgical Pathophysiology members, who were asked to report their institutional numbers of radical gastrectomy cases for cancer between 2003 and 2012. The cases were categorized according to whether the remnant stomach's status was followed for > 5 years, confirmation of MMGC, time to diagnosis, and treatment for MMGC. We calculated the "precise incidence" of MMGC by dividing the number of MMGC cases by the number of cases in which the status of remnant stomach was followed up for > 5 years.

RESULTS

The responses identified 33,731 cases of gastrectomy. The precise incidences of MMGC were 2.35% after distal gastrectomy (DG), 3.01% after PPG, 6.28% after PG (p < 0.001), and 8.21% after FPG (p < 0.001). A substantial proportion of MMGCs (36.4%) was found at 5 years after the initial surgery. The rates of MMGC treatment using endoscopic submucosal dissection were 31% after DG, 28.6% after PPG, 50.8% after PG (p < 0.001), and 67.9% after FPG (p < 0.001).

CONCLUSIONS

The incidence of MMGC was 2.4% after DG, and higher incidences were observed for larger stomach remnants. However, the proportion of cases in which MMGC could be treated using endoscopic submucosal dissection was significantly higher after PG and FPG than after DG.

Regional Lymph Node Dissection as an Additional Treatment Option to Endoscopic Resection for Expanded Indications in Gastric Cancer: a Prospective Cohort Study

Purpose

Expanded indications for endoscopic submucosal dissection (ESD) in early gastric cancer (EGC) remain controversial due to the potential risk of undertreatment after adequate lymph node dissection (LND). Regional LND (RLND) is a novel technique used for limited lymphadenectomy to avoid gastrectomy. This study established the safety and effectiveness of RNLD as an additional treatment option after ESD for expanded indications.

Materials and Methods

A total of 69 patients who met the expanded indications for ESD were prospectively enrolled from 2014 to 2017. The tumors were localized using intraoperative esophagogastroduodenoscopy (EGD) before RLND. All patients underwent RLND first, followed by conventional radical gastrectomy with LND. The locations of the preoperative and intraoperative EGD were compared. Pathologic findings of the primary lesion and the RLND status were analyzed.

Results

The concordance rates of tumor location between the preoperative and intraoperative EGD were 79.7%, 76.8%, and 63.8% according to the longitudinal, circumferential, and regional locations, respectively. Of the 4 patients (5.7%) with metastatic LNs, 3 were pathologically classified as beyond the expanded indication for ESD and 1 had a single LN metastasis in the regional lymph node.

Conclusions

RLND is a safe additional option for the treatment of EGC in patients meeting expanded indications after ESD.

Severity of postgastrectomy syndrome and quality of life after advanced gastric cancer radical gastrectomy

It has previously been suggested that postgastrectomy syndrome (PGS) is more severe in patients after surgery for advanced gastric cancer than in patients with early gastric cancer. Using the postgastrectomy syndrome assessment scale-45 (PGSAS-45), the present study aimed to determine whether PGS for postgastrectomy patients, in Kanazawa Medical University Hospital, with advanced gastric cancer was more severe than for patients with early gastric cancer. A questionnaire survey was conducted using PGSAS-45 for curative gastric cancer gastrectomy cases at Kanazawa Medical University Hospital. The questionnaire data were combined with patient background data, anonymized and moved to an unlinked file for patient privacy. Using this dataset, non-recurrent cases of distal partial gastrectomy were extracted and divided into two groups, stage IA or IB patients (group E), and stage IIA or higher (group A). The main outcome measures (MOMs) of PGSAS-45 were compared between the two groups. The participants in the present study included 35 cases in group E and 22 cases in group A. The results of a univariate analysis to compare the MOMs between the two groups showed that only the dumping subscale was significantly different in group A and was judged to be caused by the underlying bias of the background factor. There were no MOMs with significant differences in the pathological stage based on multiple regression analyses. In cases of distal partial gastrectomy, the PGS and quality of life (QoL) of patients following advanced gastric cancer surgery were similar to those of patients with early gastric cancer. The standardized treatment for advanced gastric cancer did not induce notable postoperative failures, and QoL was not impaired. In contrast, for early-stage gastric cancer cases, the present study suggests that it is necessary to distinguish metastasis-negative cases to indicate an appropriate, function-preserving curative gastrectomy.

Discovering Biomarkers in Peritoneal Metastasis of Gastric Cancer by Metabolomics

Background and Objective

Metabolomics has recently been applied in the field of oncology. In this study, we aimed to use metabolomics to explore biomarkers in peritoneal metastasis of gastric cancer.

Methods

Peritoneal lavage fluid (PLF) of 65 gastric cancer patients and related clinical data were collected from the First Hospital of Jilin University. The metabolic components were identified by liquid chromatography-mass spectrometry (LC-MS). Total ion current (TIC) spectra, principal component analysis (PCA), and the Student's t-test were used to identify differential metabolites in PLF. A support vector machine (SVM) was used to screen the differential metabolites in PLF with a weight of 100%. Cluster analysis was used to evaluate the similarity between samples. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic ability of the metabolites. Univariate and multivariate logistic regression analyses were used to identify potential risk factors for peritoneal metastasis of gastric cancer.

Results

We found the differential levels of PLF metabolites by LC-MS, TIC spectra, PCA and the t-test. Cluster analysis showed the co-occurrence of metabolites in the peritoneal metastasis group (p<0.05). ROC analysis showed the diagnostic ability of metabolites (p<0.05). Univariate and multivariate logistic regression analyses showed the potential independent risk factors for peritoneal metastasis in gastric cancer patients (p<0.05).

Conclusion

Through the statistical analysis of metabolomics, we found that TG (54:2), G3P, α-aminobutyric acid, α-CEHC, dodecanol, glutamyl alanine, 3-methylalanine, sulfite, CL (63:4), PE-NMe (40:5), TG (53:4), retinol, 3-hydroxysterol, tetradecanoic acid, MG (21:0/0:0/0:0), tridecanoic acid, myristate glycine and octacosanoic acid may be biomarkers for peritoneal metastasis of gastric cancer.

Non-exposure Simple Suturing Endoscopic Full-thickness Resection with Sentinel Basin Dissection in Patients with Early Gastric Cancer: the SENORITA 3 Pilot Study

Purpose

Recently, non-exposure simple suturing endoscopic full-thickness resection (NESS-EFTR) was developed to prevent tumor exposure to the peritoneal cavity. This study aimed to evaluate the feasibility of NESS-EFTR with sentinel basin dissection for early gastric cancer (EGC).

Materials and Methods

This was the prospective SENORITA 3 pilot. From July 2017 to January 2018, 20 patients with EGC smaller than 3 cm without an absolute indication for endoscopic submucosal dissection were enrolled. The sentinel basin was detected using Tc^99m-phytate and indocyanine green, and the NESS-EFTR procedure was performed when all sentinel basin nodes were tumor-free on frozen pathologic examination. We evaluated the complete resection and intraoperative perforation rates as well as the incidence of postoperative complications.

Results

Among the 20 enrolled patients, one dropped out due to large tumor size, while another underwent conventional laparoscopic gastrectomy due to metastatic sentinel lymph nodes. All NESS-EFTR procedures were performed in 17 of the 18 other patients (94.4%) without conversion, and the complete resection rate was 83.3% (15/18). The intraoperative perforation rate was 27.8% (5/18), and endoscopic clipping or laparoscopic suturing or stapling was performed at the perforation site. There was one case of postoperative complications treated with endoscopic clipping; the others were discharged without any event.

Conclusions

NESS-EFTR with sentinel basin dissection is a technically challenging procedure that obtains safe margins, prevents intraoperative perforation, and may be a treatment option for EGC after additional experience.

Trial Registration

ClinicalTrials.gov Identifier: NCT03216174

Precision surgical approach with lymph-node dissection in early gastric cancer

The gravest prognostic factor in early gastric cancer is lymph-node metastasis, with an incidence of about 10% overall. About two-thirds of early gastric cancer patients can be diagnosed as node-negative prior to treatment based on clinic-pathological data. Thus, the tumor can be resected by endoscopic submucosal dissection. In the remaining third, surgical resection is necessary because of the possibility of nodal metastasis. Nevertheless, almost all patients can be cured by gastrectomy with D1+ lymph-node dissection. Laparoscopic or robotic gastrectomy has become widespread in East Asia because perioperative and oncological safety are similar to open surgery. However, after D1+ gastrectomy, functional symptoms may still result. Physicians must strive to minimize post-gastrectomy symptoms and optimize long-term quality of life after this operation. Depending on the location and size of the primary lesion, preservation of the pylorus or cardia should be considered. In addition, the extent of lymph-node dissection can be individualized, and significant gastric-volume preservation can be achieved if sentinel node biopsy is used to distinguish node-negative patients. Though the surgical treatment for early gastric cancer may be less radical than in the past, the operative method itself seems to be still in transition.

Management of Early Stage Gastric and Gastroesophageal Junction Malignancies

Esophageal and gastric carcinomas are prevalent malignancies worldwide. In contrast to the poor prognosis associated with advanced stages of disease, early stage disease has a favorable prognosis. Early stage gastric cancer (ESGC) is defined as cancer in which the depth of invasion is limited to the submucosal layer of the stomach on histologic examination, regardless of lymph node status. ESGC that meets standard or expanded criteria can be treated via endoscopic mucosal resection and endoscopic submucosal dissection. Similar indications for endoscopic interventions exist for gastroesophageal junction and esophageal malignancies."

Possibility of limited gastrectomy for early gastric cancer located in the upper third of the stomach, based on the distribution of sentinel node basins

PURPOSE

Several recent studies have evaluated the feasibility of the sentinel node (SN) concept for gastric cancer. The aim of our study was to investigate limited gastrectomy with SN basin dissection in SN navigation surgery (SNNS) for patients with early-gastric cancer located in the upper-third of the stomach.

METHODS

147 patients received SNNS for early-gastric cancer at our institution. Of these, 26 patients diagnosed with early-gastric cancer < 4 cm in size and located in the upper-third of the stomach were retrospectively analyzed for the distribution of SN and SN basins.

RESULTS

In three of the 26 patients, lymph node metastasis was limited to the left gastric artery (LGA) basin. The breakdown of the basins were as follows: A single LGA basin, 19 cases; a non-single LGA basin, seven cases. A non-single LGA basin was significantly associated with the clinicopathological factors, such as tumor spread to the middle-third of the stomach, tumor location at the center of the greater curvature, and undifferentiated adenocarcinoma, compared to the single LGA basin group.

CONCLUSIONS

Our data revealed that the distribution of the SN basins in early-gastric cancer measuring less than 4 cm in size and located in the upper-third of the stomach was significantly correlated with tumor spread, tumor location, and the pathological findings.

Expression of VEGF with tumor incidence, metastasis and prognosis in human gastric carcinoma

OBJECTIVE

To analysis the expression of VEGF in gastric carcinoma cell and tumor tissue, our study determined the relationship between the expression of VEGF and tumor incidence, metastasis and prognosis in human gastric carcinoma.

METHODS

Treatment of ZD6474 at dose of 30 μmol/L was performed in gastric carcinoma cell BGC823. qPCR and Western-blot were used to analysis the mRNA and protein expression of VEGF. MTT, wound healing and Transwell experiments were conducted to study the effect of VEGF on tumor incidence, metastasis and prognosis. Sixty patients with gastric cancer were selected as the gastric cancer group, and 30 patients with gastric ulcer receiving main gastric resection were selected as control group. The survival curve of patients with gastric cancer in five years was recorded. The correlation between expression of VEGF to incidence, metastasis and prognosis of gastric cancer was evaluated by Cox multifactor regression.

RESULTS

The mRNA and protein expression of VEGF in treatment group were significantly lower than that of control group (P< 0.01). The results of MTT, wound healing and Transwell experiments were showed that the cell proliferation, migration and invasion capacity in treatment group were significantly reduced compared to that of the control group (P< 0.01). The 5-year survival rate for patients with VEGF positive expression was significantly decreased compared to the patients with VEGF expression negative (P< 0.01). The tumor size, differentiation, lymph node metastasis and tumor stage were statistically related to VEGF level (P< 0.05). The results of Cox regression multifactor analysis showed that lymph node metastasis, tumor staging and the expression of VEGF were significantly associated to the prognosis of gastric cancer patients (P< 0.05).

CONCLUSION

Our data demonstrated that the expression of VEGF was significantly related to the tumor incidence, metastasis and prognosis of patients with gastric cancer, which provides new leads to the diagnosis of gastric cancer.

Laparoscopic sentinel node navigation surgery for early gastric cancer

Currently, the most accurate method for identifying lymph node metastasis is intraoperative diagnosis by sentinel node (SN) biopsy. Based on the SNNS study-a recent large-scale, nationwide, multicenter prospective study-the SN concept seems to be scientifically valid in patients with early gastric cancer. SN biopsy is a multistep technique consisted of six essential elements: indication, the selection of a tracer, a proper tracer injection method, the objective detection of SNs, a reliable biopsy technique, and the precise detection of nodal metastasis. For SN biopsy of gastric cancer, these elements have been validated as follows: the indication should be limited to clinical T1 less than 4 cm in diameter; combination mapping with radioactive colloid and blue dye is used as the standard; and endoscopic submucosal injection is the standard tracer injection. Detection of SNs and a reliable biopsy technique are enabled by adaptation of lymphatic basin dissection, a proper biopsy technique for gastric cancer. Lymphatic basin dissection is a selective lymphadenectomy procedure for dissecting basins en bloc, collecting lymph nodes and lymphatic vessels stained with dye. Lymphatic basin dissection is superior to the ordinary pick-up method, not only for minimizing the rate of missed SNs, but also in terms of oncological safety as it complements an intraoperative frozen section diagnosis by serving as a backup dissection. Moreover, indocyanine green (ICG) fluorescence mapping has been developed in recent years. ICG fluorescence mapping is superior because of its high sensitivity and signal stability. Moreover, it is feasible for both open and laparoscopic gastrectomy in treating early gastric cancer. SN biopsy has brought dramatic changes to laparoscopic surgery for early gastric cancer. With laparoscopic SN biopsy using ICG fluorescence navigation, laparoscopic surgery for early gastric cancer has changed from the uniform standard gastrectomy with D1+ into a tailor-made function-preserving surgical procedure, such as local resection with lymphatic basin dissection.