CALD1 facilitates epithelial-mesenchymal transition progression in gastric cancer cells by modulating the PI3K-Akt pathway

BACKGROUND

CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors, including gastric cancer (GC), and is associated with tumor progression and immune infiltration; however, the roles and mechanisms of CALD1 in epithelial-mesenchymal transition (EMT) in GC are unknown.

AIM

To investigate the role and mechanism of CALD1 in GC progression, invasion, and migration.

METHODS

In this study, the relationship between CALD1 and GC, as well as the possible network regulatory mechanisms of CALD1, was investigated by bioinformatics and validated by experiments. CALD1-siRNA was synthesized and used to transfect GC cells. Cell activity was measured using the CCK-8 method, cell migration and invasive ability were measured using wound healing assay and Transwell assay, and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot. A GC cell xenograft model was established to verify the results of in vitro experiments.

RESULTS

Bioinformatics results showed that CALD1 was highly expressed in GC tissues, and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC. The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression, and a prognostic model was constructed and evaluated. The experimental results were consistent with the results of the bioinformatics analysis. The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1, with the strongest expression found in AGS and MKN45 cells. Cell activity was significantly reduced after CALD1-siRNA transfection of AGS and MKN45 cells. The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection, and the related mRNA and protein expression was altered. According to bioinformatics findings in GC samples, the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway, and was closely related to the PI3K-Akt signaling pathway. Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K, p-AKT, and p-mTOR, members of the PI3K-Akt pathway,while decreasing the expression of PTEN; PI3K-Akt inhibitor treatment decreased the expression of PI3K, p-AKT, and p-mTOR in cells overexpressing CALD1 (still higher than that in the normal group), but increased the expression of PTEN (still lower than that in the normal group). CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor. Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor. The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1, whereas the effect of overexpression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor. Animal experiments showed that tumour growth was slow after inhibition of CALD1, and the expression of some PI3K-Akt and EMT pathway proteins was altered.

CONCLUSION

Increased expression of CALD1 is a key factor in the progression, invasion, and metastasis of GC, which may be associated with regulating the PI3K-Akt pathway to promote EMT.

Gastric inflammatory myofibroblastic tumor: a case report

BACKGROUND

Inflammatory myofibroblastic tumor (IMT) of the stomach is an uncommon mesenchymal neoplasm. We present a case of gastric submucosal tumor (SMT) where the final diagnosis was IMT.

CASE PRESENTATION

A 69-year-old man presented with a 24-mm SMT on the posterior wall of the middle third of the stomach that was detected by screening upper gastrointestinal endoscopy. Abdominal contrast-enhanced computed tomography showed that the tumor was well-enhanced. Although endoscopic ultrasonography-guided biopsy was performed, the histological diagnosis was not confirmed preoperatively. Since the tumor was clinically suspected to be a gastrointestinal stromal tumor, we performed gastric wedge resection by laparoscopic-endoscopic cooperative surgery. Pathologically, proliferative spindle cells with a positive reaction for smooth muscle actin, negativity for c-kit, desmin, s-100, CD34, STAT-6, β-catenin and anaplastic lymphoma kinase 1 were identified. Hence, the tumor was finally diagnosed as an IMT originating from the stomach.

CONCLUSIONS

When an SMT of the stomach is identified, the possibility of gastric IMT should be considered.

Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors

BACKGROUND

The incidence of gastric cancer remains high, and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide. Oral contrast-enhanced ultrasonography is a simple, non-invasive, and painless method for the diagnosis of gastric tumors.

AIM

To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric tumors.

METHODS

The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological examination.

RESULTS

Among 42 patients with gastric tumors enrolled in the study, the diagnostic accordance rate was 95.2% for oral contrast-enhanced ultrasonography (n = 40) and 90.5% for electronic gastroscopy (n = 38) compared with postoperative pathological examination. The Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy, and there was no significant difference between them (P = 0.397). For the TNM staging of gastric tumors, the accuracy rate of oral contrast-enhanced ultrasonography was 81.9% for the overall T staging and 50%, 77.8%, 100%, and 100% for T1, T2, T3, and T4 staging, respectively. The sensitivity and specificity were both 100% for stages T3 and T4. The diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%, 80%, 100%, and 100% for stages N0, N1-N3, M0, and M1, respectively.

CONCLUSION

The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy, and it could be used as the preferred method for the early screening of gastric tumors.

Using machine learning to identify patients at high risk of developing low bone density or osteoporosis after gastrectomy: a 10-year multicenter retrospective analysis

INTRODUCTION

Osteoporosis that emerges subsequent to gastrectomy poses a significant threat to the long-term health of patients. The primary objective of this investigation was to formulate a machine learning algorithm capable of identifying substantial preoperative, intraoperative, and postoperative risk factors. This algorithm, in turn, would enable the anticipation of osteoporosis occurrence after gastrectomy.

METHODS

This research encompassed a cohort of 1125 patients diagnosed with gastric cancer, including 108 individuals with low bone density or osteoporosis. A total of 40 distinct variables were collected, comprising patient demographics, pertinent medical history, medication records, preoperative examination attributes, surgical procedure specifics, and intraoperative details. Four distinct machine learning algorithms-extreme gradient boosting (XGBoost), random forest (RF), support vector machine (SVM), and k-nearest neighbor algorithm (KNN)-were employed to establish the predictive model. Evaluation of the models involved receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). Shapley additive explanation (SHAP) was employed for visualization and analysis.

RESULTS

Among the four prediction models employed, the XGBoost algorithm demonstrated exceptional performance. The ROC analysis yielded excellent predictive accuracy, showcasing area under the curve (AUC) values of 0.957 and 0.896 for training and validation sets, respectively. The calibration curve further confirmed the robust predictive capacity of the XGBoost model. The DCA demonstrated a notably higher benefit rate for patients undergoing intervention based on the XGBoost model. Moreover, the AUC value of 0.73 for the external validation set indicated favorable extrapolation of the XGBoost prediction model. SHAP analysis outcomes unveiled numerous high-risk factors for osteoporosis development after gastrectomy, including a history of chronic obstructive pulmonary disease (COPD), inflammatory bowel disease (IBD), hypoproteinemia, postoperative neutrophil-to-lymphocyte ratio (NLR) exceeding 3, steroid usage history, advanced age, and absence of calcitonin use.

CONCLUSION

The osteoporosis prediction model derived through the XGBoost machine learning algorithm in this study displays remarkable predictive precision and carries significant clinical applicability.

Gastric tumor mimicking bronchial tissue associated with a laryngotracheoesophageal cleft: a case report

BACKGROUND

Laryngotracheoesophageal cleft (LTEC) is a rare disease in which the larynx and trachea communicate posteriorly to the esophagus. It is often associated with other congenital malformations, particularly gastrointestinal anomalies. Herein, we report a case of LTEC associated with a gastric polypoid lesion in bronchial tissue.

CASE PRESENTATION

A gastric mass was detected in a male fetus since week 21 of gestation using fetal ultrasonography. Esophagogastroduodenoscopy performed after birth revealed a pedunculated polypoid lesion of the gastric fornix. The patient experienced frequent vomiting and aspiration pneumonia, which persisted after nasoduodenal tube feeding. Communication between the airway and esophagus was suspected. Laryngoscopy performed 30 days later revealed an LTEC (type III). Partial gastrectomy was performed when the patient was 93 days of age. Histopathological examination revealed tumor consisting of cartilage tissue covered with a layer of respiratory epithelium.

CONCLUSION

The gastric tumor associated with LTEC exhibited structures mimicking bronchial tissue. LTEC occurs because of foregut maldevelopment, and the tumorous respiratory tissue in the stomach may have been formed from the same abnormal foregut development event as LTEC.

A case series of 10 patients undergone linear cutter/stapler guiding device-led overlapped esophagojejunostomy: a preliminary study

Background

In laparoscopic total gastrectomy with overlap esophagojejunostomy (EJS), esophageal 'false track' is easily formed during EJS. In this study, a linear cutter/stapler guiding device (LCSGD) was used in EJS, so that the linear cutting stapler can complete the technical action with high speed and high efficiency in a narrow space, while avoiding the formation of 'false passage', optimizing the quality of common opening and shortening the anastomosis time. The LCSGD is safe and feasible in laparoscopic total gastrectomy overlap EJS, and the clinical effect is satisfactory.

Methods

A retrospective, descriptive design was adopted. The clinical data of 10 gastric cancer patients admitted to the Third Department of Surgery of the Fourth Hospital of Hebei Medical University from July 2021 to November 2021 were collected. The cohort comprised 8 males and 2 females aged 50-75 years.

Results

(I) The intra-operative conditions: 10 patients received LCSGD-guided overlap EJS after radical laparoscopic total gastrectomy. Both D2 lymphadenectomy and R0 resection were achieved in these patients. No combined multiple organ resection was performed. There was neither conversion to an open thoracic or abdominal procedure nor conversion to other EJS approaches. The average time from the entry of the LCSGD into the abdominal cavity to the completion of the firing of the stapler was 1.8±0.4 minutes, the average time for manual suturing of the EJS common opening was 14.4±2.1 minutes (mean: 18±2 stitches), and the average operative time was 255±52 minutes. (II) The postoperative outcomes: the time to the first ambulation was 1.9±1.4 days, the average time to the first postoperative exhaust/defecation was 3.5±1.3 days, the average time to a semi-liquid diet was 3.6±0.7 days, and the average postoperative hospital stay was 10.4±4.1 days. All patients were smoothly discharged, without any secondary surgery, bleeding, anastomotic fistula, or duodenal stump fistula. (III) Follow-up: The telephone follow-up lasted 9-12 months. No eating disorders or anastomotic stenosis was reported. One patient experienced Visick grade II heartburn, and the condition of the remaining 9 patients was Visick grade I.

Conclusions

Application of the LCSGD in overlap EJS after laparoscopic total gastrectomy is safe and feasible, with satisfactory clinical effectiveness.

Computer analysis of abnormal proliferation and transformation cells in gastric mucosa and its clinical significance

To investigate the image computer analysis of abnormally proliferating transformed cells of gastric mucosa and its clinical significance. The pathological pictures of gastric adenomatous polyp cells, abnormally proliferating altered cells, and tubular adenocarcinoma cells in the stomach mucosa were assessed by image computer method on a total of 96 gastroscopic biopsy and ESD resection specimens. The data of cytoplasmic area, nuclear area, nuclear-cytoplasmic ratio, nuclear factor and N-heterotypic index of gastric adenomatous polyps, abnormal proliferative transformation and gastric intramucosal tubular adenocarcinoma were collected, and the mean, standard deviation and variance were calculated respectively. Standard Error, Maximum, Minimum Parameters and Statistical Structure. There were substantial discrepancies between gastric mucosal gastric adenomatous polyp cells and gastric mucosal abnormally proliferating transformed cells, according to the five data in the abnormal cells in the stomach mucosal proliferation area (p < 0.01); There was no significant difference between cells (p > 0.05). Computer analysis of cell images can provide quantitative values for the pathological diagnosis of gastric adenomatous polyp cells, abnormally proliferating transformed cells and tubular adenocarcinoma cells in the gastric mucosa, especially the degree of atypical proliferation. The monitoring of abnormally proliferated and transformed cells in gastric mucosa is of great significance for clinicians to accurately treat and track cell transformation, and to control the occurrence and development of gastric adenocarcinoma.

Running title: EEF1AKMT3/MAP2K7/TP53 axis in gastric cancerThe EEF1AKMT3/MAP2K7/TP53 axis suppresses tumor invasiveness and metastasis in gastric cancer

The importance of methylation in the tumorigenic responses of nonhistone proteins, such as TP53, PTEN, RB1, AKT, and STAT3, has been emphasized in numerous studies. In parallel, the corresponding nonhistone protein methyltransferases have been acknowledged in the pathophysiology of cancer. Thus, this study aimed to explore the pathological role of a nonhistone methyltransferase in gastric cancer (GC), identify nonhistone substrate protein, and understand the underlying mechanism. Interestingly, among the 24 methyltransferases and methyltransferase family 16 (MTF16) proteins, EEF1AKMT3 (METTL21B) expression was prominently lower in GC tissues than in normal adjacent tissues and was associated with a worse prognosis. In addition, EEF1AKMT3-knockdown induced gastric tumor invasiveness and migration. Through gain and loss-of-function studies, mass spectrometry analysis, RNA-seq, and phospho-antibody array, we identified EEF1AKMT3 as a novel tumor-suppressive methyltransferase that catalyzes the monomethylation of MAP2K7 (MKK7) at K296, thereby decreasing the phosphorylation, ubiquitination, and degradation of TP53. Furthermore, EEF1AKMT3, p-MAP2K7, and TP53 protein levels were positively correlated in GC tissues. Collectively, our results delineate the tumor-suppressive function of the EEF1AKMT3/MAP2K7/TP53 signaling axis and suggest the dysregulation of the signaling axis as potential targeted therapy in GC.

[Analysis and Treatment Experience of 25 Cases of Primary Gastric Lymphoma with Acute Upper Gastrointestinal Bleeding as the Primary Manifestation]

Objective

To summarize the clinical characteristics and treatment experience of gastric primary lymphoma with acute upper gastrointestinal bleeding as the primary manifestation, and to provide support for clinical treatment.

Methods

Information on gastric primary lymphoma patients admitted to the Department of Gastroenterology, West China Hospital of Sichuan University between January 2010 and March 2021 for acute upper gastrointestinal bleeding was retrospectively collected. Data on endoscopic morphology, tumor staging, pathology typing, severity of bleeding, risks of rebleeding, treatment and inhospital prognosis were documented and analyzed.

Results

A total of 25 patients with a mean age of 57.2 years were included in the study, all of whom presented clinically with melena (100%), 9 (36%) had hematemesis, and 6 (24%) was accompanied with abdominal pain. Twenty, or 80%, of the gastric lymphoma patients with bleeding as the primary manifestation showed endoscopically a tumor-forming phenotype (Yao Classification), mostly involving the middle and lower parts of the gastric body (44% and 32%, respectively). After conservative treatment with medication, rebleeding occurred in 4 patients during hospitalization. One of them required endoscopic hemostasis, two required surgical resection to stop the bleeding, and one decided not to undergo any further treatment. Only one patient died from infection and no death resulted directly from severe bleeding.

Conclusion

Gastric primary lymphoma presenting acute upper gastrointestinal bleeding as the sole clinical manifestation rarely occurs, but when the condition does occur, it shows a wide range of endoscopic involvement. It has a higher risk of rebleeding, and endoscopic or surgical treatment may be attempted when conservative medication treatment for acute upper gastrointestinal bleeding fails.

Robotic excision of gastric and duodenal gastrointestinal stromal tumor

Gastrointestinal stromal tumors (GIST) originate from interstitial cells of Cajal and are most often located in the stomach. The mainstay of treatment for GIST is surgical resection. Laparoscopic wedge resection of gastric GIST using linear staplers has been commonly performed and shown to be feasible and safe. However, this technique is not suitable for tumors at particular anatomical locations such as the gastric cardia near the gastroesophageal junction, the lesser curvature of stomach, and the duodenum. The robotic surgery platform with augmented surgical skills has enabled precise dissection and suturing. We consider robotic GIST excision with primary suture closure to be useful for lesions in the above-mentioned locations. In this video, we demonstrate our techniques of robotic excision of gastric and duodenal GIST. At our institution, 13 patients underwent robotic excision of gastric and duodenal GIST between November 2018 and July 2021. Tumor locations included the cardia (n = 2), gastric body (n = 10) [lesser curvature (n = 3) and other (n = 7)], and the duodenum (n = 1). There were no conversions to open laparotomy. The median operation time was 160 min (range 80-270), and median blood loss was 25 mL (range 5-50). The median length of hospital stay was 3 days (range 1-4). There were no complications or readmissions within 90 days. We demonstrated the feasibility and safety of robotic resection of GIST located at the stomach and duodenum. Especially in anatomically challenging locations where the stapling technique is not suitable, robotic approaches are considered useful for performing precise excision.

Omitting nasogastric tube placement after gastrectomy does not enhance postoperative recovery: a propensity score matched analysis

PURPOSE

Enhanced recovery after surgery (ERAS) program has become the main trend in gastrointestinal surgery. This study aims to investigate factors influencing the decision-making of nasogastric tube (NGT) placement and its safety and efficacy after gastrectomy.

METHODS

We analyzed our prospectively maintained database including 287 patients who underwent elective gastrectomy in our department from January 1 to December 31, 2017. All cases were divided into two groups, namely, the no-NGT group and the NGT group. Logistic regression was used to analyze factors that affected the decision of NGT placement, and propensity score matching (PSM) was later applied to balance those factors for the analysis of safety outcomes between groups.

RESULTS

Multivariate analysis showed resection range (p = 0.004, proximal gastrectomy: OR = 4.555, 95%CI = 1.392-14.905, p = 0.016; total gastrectomy: OR = 1.990, 95%CI = 1.205-3.287, p = 0.009) was the only independent risk factor of NGT placement. NGT was omitted in the majority (58.8%) of distal gastrectomy but only in 42.5% and 25% in total and proximal gastrectomy. After PSM, we found no significant differences between patients with or without NGT in postoperative hospital stay, time to first flatus and defecation, time to fluid and semi-fluid diet, rate of reinsertion, or hospitalization expenditure (p > 0.05, respectively). The incidence of postoperative complications in the two groups were 21.7% and 23.5%, respectively (p = 0.753), and the incidence of major complications was 7.0% and 9.6% (p = 0.472).

CONCLUSION

The decision-making of NGT placement is mainly influenced by the resection range. Omitting NGT is a safe approach in all types of gastrectomy but was not able to enhance the recovery in our practice.

Propofol Sedation in the Endoscopy Room versus Operation Room during Endoscopic Submucosal Dissection for Gastric Tumors: A Propensity Score-Matching Analysis

BACKGROUND/AIMS

The present study was performed to compare the safety of sedation with propofol during endoscopic submucosal dissection (ESD) for gastric tumors under sedation in the endoscopy room by an endoscopist versus sedation in the operation room by an anesthesiologist.

METHODS

In total, 638 patients with gastric tumors who underwent ESD from January 2011 to August 2017 at Ureshino Medical Center and Saga Medical Center Koseikan were retrospectively reviewed. The patients were divided into 2 groups: those who underwent ESD in the endoscopy room (Group E, n = 532) and those who underwent ESD in the operation room (Group O, n = 106). Propensity score matching was applied for evaluation. The treatment outcome of ESD and the adverse events of sedation during ESD (desaturation, hypotension, bradycardia, and arrhythmia) were compared between the 2 groups to consider the safety of ESD.

RESULTS

The propensity score-matching analysis created 82 matched pairs. Adjusted comparisons between Groups E and O showed similar treatment outcomes of ESD for gastric tumors. There were no significant differences in the treatment outcomes, anesthesia time, and mean propofol dose between the 2 groups. With respect to adverse events, desaturation occurred more often in Group E than Group O (18.3 vs. 3.7%, respectively; p = 0.005). There were no significant differences in other adverse events (hypotension, bradycardia, and arrhythmia) between the 2 groups.

CONCLUSION

Sedation with propofol in the operation room might be required to ensure safer application of ESD for gastric tumors. However, a decrease in the desaturation rate was the only disadvantage of sedation in the endoscopy room.

Surgical resection of gastric gastrointestinal stromal tumors (GIST) in octogenarians

BACKGROUND

Localized gastrointestinal stromal tumors (GISTs) are rare tumors typically managed with surgery, but outcomes among octogenarians remain less studied.

METHODS

Octogenarian patients with stage I-III gastric GISTs were identified from the National Cancer Database and classified by resection status. Cox regression and Kaplan-Meier survival analyses analyzed 5-year overall survival (OS). Ninety-day mortality was analyzed following 1:1 propensity score matching.

RESULTS

Identified octogenarians (N = 949) who underwent resection (N = 632) had improved adjusted OS (71% vs 59.6%, HR 0.75, p 0.049) as compared to non-resected patients. Following matching, 90-day mortality was 5.7% and 11% in resected and non-resected patients (p 0.052), respectively. After exclusion of patients with 90-day mortality, resected patients maintained an OS advantage (77.3% vs 71.1%, HR 0.64, p 0.028).

CONCLUSIONS

The majority of octogenarians with localized gastric GIST are treated with surgery portending improved survival but an appreciable mortality, suggesting a necessity for careful selection of older patients for surgery.

Carney triad: A case report, characteristics and literature review of this rare entity

•

Carney's syndrome gastric tumors differ in their characteristics from gastrointestinal stromal tumors (GIST).

•

Carney syndrome could have different forms of presentation.

•

The diagnosis of carney syndrome could occur up to 30 years after the diagnosis of the first tumor.

Introduction and importance

Carney triad is a rare entity of unknown etiology, characterized by the association of tumors with low incidence such as: gastric leiomyosarcoma, pulmonary chondroma and extra-adrenal paraganglioma. We show a case of Carney triad diagnosed in our center that has some different characteristics to the typical presentation of this patology, and a review of the literature.

Case presentation

We present the case of a 47-year-old men who was admitted to our hospital for upper gastrointestinal bleeding and anemia. The patient was diagnosed of gastric GIST (gastrointestinal stromal tumor), pulmonary nodule and retroperitoneal nodule close to iliac bifurcation. A review of his medical history revealed that he had undergone surgery at 18-year-old for gastric leiomiosarcoma, subtotal gastrectomy performed with gastroenteric anastomosis type Billroth II.

The patient underwent total gastrectomy with a end-lateral esophago-jejune mechanical anastomosis and retroperitoneal tumor was also excised. Pathological result confirmed gastric GIST, and extra-adrenal paraganglioma.

Clinical discussion

We review the available literature to determinate the characteristics and the most appropriate management for this syndrome. The trend is surgical treatment of gastric GIST and paraganglioma, preferred conservative treatment in pulmonary chondroma.

It is under discussion whether gastric tumors Carney syndrome is considered GIST, because the Carney triad lesions in stomach are different clinically, pathologically, and etiologically from GIST of stomach.

Conclusion

Carney's triad is a low prevalence entity, with a limited number of publications, so the presentation of the syndrome may be different from the presentation described in the literature.

LncRNA LIFR-AS1 promotes proliferation and invasion of gastric cancer cell via miR-29a-3p/COL1A2 axis

BACKGROUND

LncRNA was known to be closely associated with the progression of human tumors. The role of lncRNA LIFR-AS1 in the pathogenesis and progression of gastric tumor is still unclear. The aim of this study was to investigate the function of LIFR-AS1 and the underlying mechanism in the pathogenesis and progression of gastric cancer.

METHODS

QRT-PCR was used to evaluate the expression of LIFR-AS1, miR-29a-3p and COL1A2 in gastric tumor tissues and cells. Western blotting was used to evaluate the protein expression of COL1A2 in gastric tumor cells. CCK-8 assay, transwell assay and flow cytometry were used to evaluate the roles of LIFR-AS1, miR-29a-3p and COL1A2 in cell proliferation, invasion, migration and apoptosis. The relationship among LIFR-AS1, miR-29a-3p and COL1A2 was assessed by bioinformatics analyses and luciferase reporter assay.

RESULTS

The expression levels of LIFR-AS1 were significantly increased in gastric tumor tissues and cells, while the expression levels of miR-29a-3p were decreased. The expression of miR-29a-3p was negatively correlated with the expression of LIFR-AS1 in gastric cancer tumor tissues. Knocking down of LIFR-AS1 inhibited proliferation, invasion and migration of gastric tumor cells, and induced apoptosis of gastric tumor cells. Bioinformatics analyses and integrated experiments revealed that LIFR-AS1 elevated the expression of COL1A2 through sponging miR-29a-3p, which further resulted in the progression of gastric tumor.

CONCLUSION

LIFR-AS1 plays an important role as a competing endogenous RNA in gastric tumor pathogenesis and may be a potential target for the diagnosis and treatment of gastric tumor.

Gastric carcinoma and renal cell carcinoma as an atypical presentation of multiple primary malignancies: a case report and review of the literature

Background

Gastric carcinoma (GC) with second primary malignancy (SPM) is the most frequent combination within the multiple primary malignancies (MPM) group. The presentation of a GC associated with a synchronized SPM in the kidney is extremely rare and unusual. This study presents a rare case of synchronous tumors, describes the main associated risk factors, and emphasizes the need to rule out SPM.

Main body

We present the case of a 63-year-old Hispanic woman with a history of smoking, weight loss, and gastrointestinal (GI) bleeding. GC was diagnosed by endoscopy, and during her workup for metastatic disease, a synchronous SPM was noted in the left kidney. The patient underwent resection of both tumors with a satisfactory postoperative course. A systematic review of the literature was performed using the Medline/PubMed, Science Direct, Scopus, and Google Scholar databases. A search of the literature yielded 13 relevant articles, in which the following main risk factors were reported: the treatment utilized, the grade and clinical stage, histopathological report, and in some cases survival. It is concluded that advanced age (> 60 years) and smoking are the main associated risk factors.

Conclusion

Gastric carcinoma is the second most frequent neoplasm of the GI tract and the main neoplasm that presents a SPM. MPM screening is recommended in patients with gastric cancer. The clinical discovery of MPM of renal origin is rare and hence the importance of the current report.

PD-L1 and HER2 Expression in Gastroesophageal Cancer: a Matched Case Control Study

Immunotherapy with check-point inhibitors serves as a promising treatment strategy in patients with upper gastrointestinal (GI) tumors. Human epidermal growth factor receptor 2 (HER2) is the only identified therapeutic target in upper GI tumors, whose potential interaction with programmed death-ligand 1 (PD-L1) is unknown. The aim of this study was the investigation of PD-L1 and HER2 in upper GI tumors. We retrospectively identified patients with HER2 positive gastroesophageal cancers and matched them with a HER2 negative group. We investigated the tumor specimens for HER2 status and PD-L1 expression, with the following assessments being performed: i) staining of tumor cells in terms of tumor proportion score (TPS), ii) staining for tumor-associated immune cells (TAIs), iii) interface pattern and iv) combined positive score (CPS). Both HER2 positive and negative group consisted of 59 patients. Expression of PD-L1 in TAIs and interface pattern were associated with a favorable outcome (p = 0.02, HR = 0.8; p = 0.04, HR = 0.39; respectively) in patients with localized disease, whereas TPS was associated with an unfavorable outcome in patients with advanced tumor (p = 0.02, HR = 1.4). These effects were HER2 independent. PD-L1 expression in its different assessment is equally observed in HER2 positive and negative patients. Future studies will show whether dual inhibition of HER2 and PD-L1 improves survival of this selected patient population.

Gastric leiomyoma casusing gastrointestinal bleeding

Los leiomiomas gástricos son tumoraciones submucosas benignas, poco comunes, que se originan del músculo liso. Clínicamente son asintomáticos, con buen pronóstico y con pocas complicaciones a largo plazo. Reportamos el caso de un joven de 16 años que se presenta a la clínica con melena y dolor abdominal. En la endoscopia se reporta una tumoración prepilórica, ulcerada y cubierta de fibrina. El estudio histopatológico mostró una neoplasia mesenquimal con positividad inmunohistoquimica para desmina y actina, así como negatividad para C-kit, DOG-1 y S-100, compatible con leiomioma gástrico. Fue intervenido quirúrgicamente realizándose antrectomía laparoscópica con reconstrucción en Y de Roux de manera exitosa.

Gastric leiomyomas are rare, benign submucosal tumors originating from smooth muscle cells. They are usually asymptomatic, having good prognosis with limited long-term complications. A 16-year-old young man comes to our clinic and reports melena and abdominal pain. Upper endoscopy revealed a prepyloric, ulcerated, fibrin-covered tumor. Histopathological examination showed a positive immunohistochemical stain mesenchymal neoplasm for desmin and muscle actin, being negative for C-kit, DOG-1 and S100 proteins, consistent with gastric leiomyoma. Antrectomy with Roux-en-Y gastrojejunostomy was successfully performed.

Minimally invasive options for gastrointestinal stromal tumors of the stomach

BACKGROUND

Gastrointestinal stromal tumors (GIST) are rare mesenchymal tumors, most commonly arising in the stomach. Surgical resection remains the mainstay of cure, and can often be accomplished laparoscopically. Tumor size and location guide selection of appropriate resection technique.

METHODS

A retrospective review of all patients undergoing surgery at a single academic center between 2000 and 2018. Comparisons and descriptive statistics performed using student's t test and χ² test.

RESULTS

77 patients underwent resection for gastric GIST, 53 (68%) laparoscopic. Patients undergoing open operations had significantly larger tumors (4 cm vs 7 cm, p < 0.001). Operative time was not significantly different between the two groups (117 min vs 104 min, p = 0.26). Median length of stay was significantly shorter for laparoscopic resection, and postoperative complication rate was lower. A review of the operative notes revealed four types of resection: non-anatomic stapled wedge resection, resection of a full-thickness "disk" of stomach around the tumor with primary closure, formal partial gastrectomy with reconstruction, and laparoscopic transgastric (endoluminal) resection.

CONCLUSION

Non-anatomic resection (wedge or disk) is most feasible for tumors on the greater curve or gastric body, far enough from the pylorus and gastroesophageal junction to avoid narrowing inflow or outflow. A partial gastrectomy may be required for large tumors or those encroaching on the esophagus or pylorus. For small intraluminal tumors, a laparoscopic transgastric approach is ideal. This review of the technical details of each type of resection can aid in selecting the ideal approach for difficult tumors.

Use of omental patch and endoscopic closure technique as an alternative to surgery after endoscopic full thickness resection of gastric intestinal stromal tumors: A series of cases

BACKGROUND

Gastrointestinal stromal tumors (GISTs) originate from interstitial cells of Cajal. GISTs can occur anywhere along the gastrointestinal tract. Large lesions have traditionally been removed surgically. However, with recent innovations in advanced endoscopy, GISTs located within the stomach are now removed endoscopically. We describe a new innovative endoscopic technique to close large and hard to access defects after endoscopic full-thickness resection of gastric GISTs.

CASE SUMMARY

We present a series of three patients who were diagnosed with a gastric GIST. All patients underwent full-thickness endoscopic resection. In all cases, for closure of the surgical bed, conventional endoscopic techniques including hemoclips, endoloop and suturing were unsuccessful. We performed a new technique in which we pulled omental fat into the gastric lumen and completely closed the defect using endoscopic devices. All patients performed well post-procedure and computed tomography was carried out one day after the procedures which showed no extravasation of contrast.

CONCLUSION

The omental plug technique may be used as an alternative to surgery in selected cases of gastric perforation.

Primary epithelioid rhabdomyosarcoma of the stomach: a case report and review of literature

BACKGROUND

Epithelioid rhabdomyosarcoma is a rare tumor that generally occurs in the bladder, the parotid gland, or the skin of the neck. We describe an unusual case of primary epithelioid rhabdomyosarcoma of the stomach and review the literature.

CASE PRESENTATION

A 64-year-old woman presented with a lesion at the gastroesophageal junction. Histopathological examination showed irregularly sized round cells with low cytoplasmic content and eccentric nuclei. Mitotic figures were present. Fibrovascular septa and areas of necrosis were observed between tumor cells. Tumor cells were strongly positive for MyoD1, desmin, and myogenin, and weakly positive for actin, CD56, and PGP9.5. The ki-67 index was ≥90%.

CONCLUSIONS

Primary epithelioid rhabdomyosarcoma of the stomach is extremely rare. Better awareness of this entity is necessary for early diagnosis and treatment.

"Homomorphic" Tumor Metastases as an Endodiagnostic Clue: A Case Series of Renal-Cell Carcinoma Metastatic to the Stomach

Distinguishing between a primary malignancy and a metastasis can be challenging in some cases. Herein, we describe 2 cases of gastric lesions that were endoscopically sampled and ultimately found to be metastatic from a renal-cell carcinoma. In both cases, the gastric metastases were endoscopically homomorphic to the primary organ (the kidney); i.e., grossly resembling and thus providing an endoscopic clue as to the primary tumor source. We report on the evaluation of obscure metastatic gastric involvement of malignancy and present the concept of homomorphism as a potential diagnostic clue in determining the source of unknown and often unsuspected primary malignancy.

Gastric aggressive fibromatosis: report of a case and review of the literature

OBJECTIVES

To describe a rare case of aggressive fibromatosis of the stomach and discuss the differential diagnoses.

METHODS

A 47-year-old man presented with nonspecific abdominal pain. Gastroscopy revealed stomach wall swelling. An antral gastrectomy was performed. Histological examination revealed spindle-shaped cells and morphology typical of aggressive fibromatosis. We performed a literature search to identify conditions with features similar to those of aggressive fibromatosis.

RESULTS

Aggressive fibromatosis does not metastasize, but it is locally invasive and has a tendency to relapse; however, our patient has not had recurrence > 1 year after surgery. Aggressive fibromatosis of the stomach may be confused with an inflammatory fibroid polyp, a gastrointestinal stromal tumor, schwannoma, leiomyoma, inflammatory myofibroblastic tumor, scirrhous carcinoma of the stomach, follicular dendritic cell sarcoma, inflammatory malignant fibrous histiocytoma, myofibroma/myofibromatosis, and solitary fibrous tumor of the stomach.

CONCLUSIONS

Aggressive fibromatosis of the stomach is a rare spindle cell tumor that must be differentiated from a variety of conditions.

Clinicopathological Features of Metastatic Gastric Tumors Originating From Breast Cancer: Analysis of Eleven Cases

Background

Metastatic gastric tumor originating from breast cancer (MGTBC) is rare. Endoscopically, gastric cancer (GC)-like lesions and submucosal tumors (SMT) are the features of MGTBC. Their clinicopathological characteristics are currently uncertain. We analyzed the clinicopathological characteristics of 11 patients with MGTBC to better understand the disease progression and thereby improve early detection methods.

Methods

From 2006 to 2016, 11 patients with MGTBC diagnosed by esophagogastroduodenoscopy (EGD) were included.

Results

All 11 patients were women, with a median age of 57 years. Histological examination revealed six cases with solid tubular components and five cases with invasive lobular carcinoma components. Melena was the most common symptom; however, asymptomatic cases were also common. Seven and four cases had GC-like lesions and SMTs, respectively. Six of the seven cases had GC-like lesions with peritoneal metastasis, whereas none of the four SMT cases had peritoneal metastasis (P = 0.015). The median overall survival (OS) in all cases was 26 months (range, 1 - 42 months). OS in cases treated with chemotherapy after a diagnosis of gastric metastases was significantly better than that in those treated without chemotherapy (P = 0.047). One patient showed gradual transformation from an SMT-type lesion to a Borrmann type 4-like appearance.

Conclusions

MGTBC is a rare occurrence; however, it should be considered when gastric tumors, especially GC-like lesions in patients with a medical history of breast cancer are found. Patients with breast cancer, especially invasive lobular carcinoma, should undergo screening EGD regularly to detect gastric metastases early and receive chemotherapy to obtain good outcomes.

[Clinical characteristics and treatment strategies for early-stage primary gastric diffuse large B-cell lymphoma]

Objective: Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) is the most common non-Hodgkin lymphoma (NHL) of extranodal origin. Most patients with PG-DLBCL had localized disease (stage Ⅰ or Ⅱ) at presentation, and will achieve complete response (CR) after induction chemotherapy. However, there has been little consensus regarding whether optimal treatment is provided by chemotherapy alone or chemotherapy plus radiotherapy, nor the treatment outcome from the addition of rituximab in localized-stage PG-DLBCL. Methods: Patients with Stage ⅠE and ⅡE PG-DLBCL were retrospectively analyzed. Patients have not undergone surgery, have received at least 3 cycles of R-CHOP or CHOP-like chemotherapy as initial therapy, and achieved CR or partial response (PR) were enrolled. Results: A total of 91 patients were studied. The median age was 51 years, included 47 males and 44 females. Fifty-two patients were at Stage ⅠE and 39 at Stage ⅡE, 64 (70.3%) patients received R-CHOP-like regimens, and 27 (29.7%) received CHOP-like regimens, the median chemotherapy cycle was 6 (3-8). Among the 91 patients, 80 (87.9%) patients achieved CR from induction chemotherapy, 11(12.1%) was evaluated PR. Of CR patients, 48 patients (60%) underwent consolidating radiotherapy and 32 patients (40%) did not receive radiotherapy; all PR patients received salvage radiotherapy. CR patients with and without radiation therapy had 4-year progression-free survival (PFS) rates of 96.4% and 96.7%, respectively (χ(2) = 0.546, P=0.46); 7/11 (63.6%) PR patients achieved CR after radiotherapy, with a median follow-up of 41 months, they were all disease free. For patients treated with R-CHOP or CHOP-like regimens, the 4-year PFS was 93.2% and 89.7%, respectively (χ(2)=0.096, P=0.757). Conclusions: Consolidation radiotherapy failed to improve the outcome for early-stage PG-DLBCL, while for PR patients, salvage radiotherapy increased CR rate and improved survival. The addition of rituximab to CHOP did not improve the efficacy.

DNMT3B -579 G>T Promoter Polymorphism and the Risk of Gastric Cancer in the West of Iran

BACKGROUND

Many studies have suggested that modulation of DNMT3B function caused by single nucleotide polymorphisms of the DNMT3B promoter region may underlie the susceptibility to various cancers such as tumors of the digestive system. The aim of this study was to investigate the effect of -579 G>T polymorphism in the promoter of the DNMT3B gene on risk of gastric cancer in a population from West Iran.

PATIENTS AND METHODS

We conducted a case-control study in 100 gastric cancer patients and 112 cancer-free controls to assess the correlation between DNMT3B -579 G>T (rs1569686) polymorphism and the risk of gastric cancer. Detection of genotypes of DNMT3B G39179T polymorphism was analyzed by PCR-RFLP.

RESULTS

There was no significant difference in the distribution of DNMT3B -579 G>T genotypes between the cases and controls. However, in the stratified analysis by clinicopathological characteristic types, we found that statistically, the risk susceptibility to gastric cancer was significantly associated with tumor grade II and GT/TT genotype of patients, compared to patients having GG genotype, (OR = 5.4737, 95% CI = 1.4746. 20.3184, P = 0.01).

CONCLUSIONS

Our study suggested that the -579 T allele may increase the relative risk for the progression of clinicopathological characteristic of tumor grade of gastric cancer patients.

SSAT State-of-the-Art Conference: Current Surgical Management of Gastric Tumors

INTRODUCTION

The current era of gastric surgery is marked by low morbidity and mortality rates, innovative strategies to approach resections with a minimally invasive fashion or hyperthermic intraperitoneal chemotherapy (HIPEC), as well as improved understanding of the biology of sporadic and hereditary stromal, neuroendocrine, and epithelial malignancies.

METHODS

In 2017, the Society for Surgery of the Alimentary Tract convened a State-of-the-Art Conference on Current Surgical Management of Gastric Tumors with both international experts and emerging leaders in the field of gastric surgery.

RESULTS

Martin D. McCarter, MD of the University of Colorado discussed the current management of gastric gastrointestinal stromal tumors (GIST). Kaitlyn J. Kelly, MD of the University of California, San Diego discussed the management of gastric carcinoid tumors. Jeffrey A. Norton of Stanford University discussed recent advances in the management of gastric adenocarcinoma including a focus on hereditary diffuse gastric cancer (HDGC). Joseph Kim, MD of Stony Brook University discussed a systematic approach to minimally invasive gastrectomy for cancer. Joyce Wong, MD of Pennsylvania State University discussed the role for cytoreductive surgery (CRS) and HIPEC for gastric adenocarcinoma.

CONCLUSIONS

This review provides gastrointestinal surgeons with a concise update on the current surgical management of gastric tumors.

Usefulness of conventional and low-dose hydro-CT in the diagnosis of gastric tumors in comparison to endoscopy

PURPOSE

The aim of this retrospective study was to evaluate the usefulness of hydro-CT in the diagnosis of gastric tumors in comparison to endoscopy.

MATERIAL AND METHODS

The study involved 40 patients with a diagnosis of gastric tumor established by histopathology who underwent endoscopy and conventional or low-dose hydro-CT. Hydro-CT images were retrospectively analyzed based on the consensus of two radiologists who were blinded to the endoscopy findings. The diagnostic accuracy of hydro-CT and endoscopy for the diagnosis of gastric tumors was evaluated using the results of the histopathological examination as the reference standard.

RESULTS

Histopathology confirmed the presence of gastric cancer in 28 patients (70%), while gastrointestinal stromal tumors (GISTs) were recognized in the remaining 12 cases (30%). Correct diagnoses of the type of gastric tumor in hydro-CT were obtained in 37 patients (92.5%). This was not significantly different from the 85% accuracy of endoscopy. Further analysis showed that the correctness of GIST diagnosis in endoscopy and hydro-CT also did not differ significantly (91.7% and 100% respectively). The percentage of correctly diagnosed malignant lesions in hydro-CT was lower than for GISTs at 89.29%, while in endoscopy it was insignificantly lower (82.14%). The diagnostic accuracy of conventional and low-dose hydro-CT in the diagnosis of gastric tumors (95% and 90% respectively) was not significantly different.

CONCLUSIONS

Conventional and low-dose hydro-CT may be a valuable non-invasive diagnostic method in the diagnosis of gastric tumors for patients who have contraindications to endoscopy or who are unable to undergo gastric biopsy.

Postoperative bleeding after gastric endoscopic submucosal dissection in patients receiving antithrombotic therapy

BACKGROUND AND AIMS

It is controversial whether antithrombotic therapy increases the risk of bleeding after endoscopic submucosal dissection (ESD). The aim of this study was to evaluate the effects of antithrombotic therapy on gastric ESD.

METHODS

Patients who underwent gastric ESD at Toranomon Hospital between April 2005 and July 2014 were enrolled. The risk of post-ESD bleeding was evaluated by multivariate logistic regression analysis.

RESULTS

Of 1781 patients enrolled, 253 were taking an antithrombotic; 186 discontinued taking a single antithrombotic (n = 150) or multiple antithrombotics (n = 36) before ESD, whereas 15 continued taking a single antiplatelet agent and another 52 switched to heparin alternative therapy during the peri-ESD period. Post-ESD bleeding occurred in 101 patients (5.7 %): 68 patients (3.8 %) who did not take an antithrombotic, 11 patients (7.3 %) who discontinued taking a single antithrombotic, six patients (16.7 %) who discontinued taking multiple antithrombotics, one patient (6.7 %) who continued taking a single antiplatelet agent, and 15 patients (28.8 %) who switched to heparin therapy. In multivariate analysis, heparin alternative therapy [odds ratio (OR) 10.04, 95 % confidence interval (CI) 4.35-23.16], discontinuation of the use of multiple antithrombotics before ESD (OR 5.44, 95 % CI 2.00-14.79), tumor location in the lower third of the stomach (OR 2.17, 95 % CI: 1.32-3.58), and a long procedure time (100 min or greater; OR 2.00, 95 % CI 1.25-3.20) were independent risk factors for post-ESD bleeding. Among 52 subjects who switched to heparin therapy, one developed acute renal infarction and one developed cerebral bleeding.

CONCLUSIONS

Because heparin alternative therapy significantly increases the risk of post-ESD bleeding and may not decrease the risk of thromboembolic events, other options should be considered for patients receiving anticoagulation therapy.

Role of Endoscopic Ultrasound for the Diagnosis of Isolated Gastric Cavernous Haemangioma

Isolated gastric cavernous haemangioma is extremely rare in the stomach. Historically, endoscopy, computed tomography and MRI had been used to diagnose gastric cavernous haemangioma. Biopsy, is not an option due to its vascular nature and submucosal location. We report an isolated gastric cavernous haemangioma that was diagnosed by end-oscopic ultrasound in a 25-year-old male and treated by laparotomy. The final diagnosis of cavernous haemagioma was confirmed by post-operative pathology. There was no recurrence during 3-month follow-up period.

Endoscopic full thickness resection for gastric tumors originating from muscularis propria

AIM: To do systematic review of current literature for endoscopic full thickness resection (EFTR) technique for gastric tumors originating from muscularis propria.

METHODS: An extensive English literature search was done till December 2015; using PubMed and Google scholar to identify the peer reviewed original and review articles using keywords-EFTR, gastric tumor, muscularis propria. Human only studies were included. The references of pertinent studies were manually searched to identify additional relevant studies. The indications, procedural details, success rates, clinical outcomes, complications and limitations were considered. For the purpose of review, data from individual studies was combined to calculate mean. No other statistical test was applied.

RESULTS: A total of 9 original articles were identified. Four articles were from same institute and the time frames of these studies were overlapping. To avoid duplication of data, only the study with patients over the longest time interval was included and other three were excluded. In total six studies were included in the final review. In our systematic review, the mean success rate for EFTR of gastric tumors originating from muscularis propria was 96.8%. The mean procedure time varied from a minimum of 37 min to a maximum of 105 min. There was no reported mortality from the technique itself. The most common histological diagnosis was gastrointestinal stromal tumors and leiomyoma. Gastric wall defect closure by either metallic clips or over the scope clip (OTSC) had similar outcomes although experience with OTSC was limited to smaller lesions (< 3 cm).

CONCLUSION: EFTR is a minimally invasive technique to resect gastric submucosal tumors originating from muscularis propria with a high success rate and low complication rate.

Expression of p-STAT3 and vascular endothelial growth factor in MNNG-induced precancerous lesions and gastric tumors in rats

AIM: To investigate the dynamic expression of p-signal transducer and activator of transcription 3 (STAT3) and vascular endothelial growth factor (VEGF) in the formation of gastric tumors induced by drinking water containing N-methyl-N’-nitro-N-nitrosoguanidine (MNNG) in Wistar rats.

METHODS: One hundred and twenty Wistar rats were randomly divided into two groups (60 in each group): Control group and Model group. The rats in each group were then randomly divided into three groups (20 in each group): C/M15, C/M25 and C/M40 (15, 25 and 40 represent the number of feeding weeks from termination). Rats in the control group received normal drinking water and rats in the model group received drinking water containing 100 μg/mL MNNG. Stomach tissues were collected at the end of the 15^th, 25^th and 40^th week, respectively, for microscopic measurement using hematoxylin and eosin staining. The expression of p-STAT3 and VEGF in different pathological types of gastric tissue, including normal, inflammation, atrophy, hyperplasia and gastric stromal tumor, was observed by immunohistochemistry and Western blot, and the corelation between p-STAT3 and VEGF was analyzed.

RESULTS: (1) The expression of p-STAT3 in tissue with gastritis, atrophy, dysplasia and gastric stromal tumor were significantly increased in the model group compared with the control group (2.5 ± 1.0, 2.75 ± 0.36, 6.2 ± 0.45, 5.67 ± 0.55 vs 0.75 ± 0.36, P = 0.026, 0.035, 0.001, 0.002, respectively); the expression of p-STAT3 in tissue with dysplasia was higher than that in samples with gastritis or atrophy (6.2 ± 0.45 vs 2.5 ± 1.0, P = 0.006; 6.2 ± 0.45 vs 2.75 ± 0.36, P = 0.005, respectively); however, the expression of p-STAT3 in gastritis and atrophy was not significantly different (P > 0.05); (2) the expression of VEGF in tissue with gastritis, atrophy, dysplasia and gastric stromal tumor was significantly increased in the model group compared with normal gastric mucosa; and the expression of VEGF in tissue with dysplasia was higher than that in tissue with inflammation and atrophy (10.8 ± 1.96 vs 7.62 ± 0.25, P = 0.029; 10.8 ± 1.96 vs 6.26 ± 0.76, P = 0.033, respectively); similarly, the expression of VEGF in tissue with gastritis and atrophy was not significantly different (P > 0.05); and (3) the expression of VEGF was positively correlated with p-STAT3.

CONCLUSION: p-STAT3 plays an important role in gastric cancer formation by regulating the expression of VEGF to promote the progression of gastric tumor from gastritis.

Endoscopic Submucosal Dissection for Early Gastric Neoplasia Occurring in the Remnant Stomach after Distal Gastrectomy

Background/Aims:

Endoscopic submucosal dissection (ESD) for tumors occurring in the remnant stomach is technically difficult to perform because of limited working space and severe fibrosis and staples present around the suture line. We aimed to elucidate the feasibility and clinical outcomes of performing ESD for tumors in the remnant stomach.

Methods:

Between December 2007 and January 2013, 18 patients underwent ESD for tumors (six adenomas and 12 differentiated-type early gastric cancers [EGCs]) occurring in the remnant stomach after distal gastrectomy. Clinicopathologic features and clinical outcomes after ESD were retrospectively analyzed.

Results:

Two-thirds of the lesions were located on the body, and half were located on the suture line. En bloc resection, R0 resection, and en bloc with R0 resection rates were 88.9%, 100%, and 88.9%, respectively. Curative resection rate for EGC was 91.7%. Perforation occurred in one patient (5.6%) and was successfully managed by endoscopic closure with metallic clips and conservative management. There was no significant bleeding after ESD. During a median follow-up of 47.5 months, no local, metachronous, or extragastric recurrence was seen for either EGC or adenoma lesions.

Conclusions:

ESD is a feasible and effective treatment modality and can be considered a primary intervention for early gastric neoplasia occurring in the remnant stomach.

Gastric metastases not resulting from direct invasion: Report of 5 cases and review of the literature

Gastric metastases not resulting from direct invasion are rare. Clinically, these patients present with nonspecific symptoms, which easily lead to missed diagnosis or misdiagnosis. MSCT findings of the disease may vary but often have characteristic features, different from those of gastric stromal tumors and primary gastric cancer. Thus, for cancer patients with gastrointestinal symptoms, medical imaging workers should improve the recognition and vigilance of the disease. Careful identification of the characteristic MSCT findings combined with the clinical history can help provide a suggestive diagnosis.

The role of miR-100-mediated Notch pathway in apoptosis of gastric tumor cells

MicroRNAs (miRNAs) are small non-coding regulatory molecules that influence many biological functions, including apoptosis, but their role in the regulation of apoptosis in gastric tumor cells has not been intensively investigated. Here, we showed that miR-100 was specifically upregulated in human epithelium-derived gastric cancer cells and that silencing miR-100 expression in human gastric epithelial cancer cells initiated a robust apoptotic response in vitro. Our in vivo assays indicated that the development of gastric cancer was inhibited by the miR-100 antagonism via initiating apoptosis of tumor. The results presented that antagonism of miR-100 increased the expression level of HS3ST2, the target gene of miR-100, and further resulted in the activation of the Notch-apoptosis pathway in tumor cells. The data also revealed that silencing of miR-100 expression sensitized gastric cancer cells to chemotherapy. Therefore our study presented a novel miR-100 mediated Notch pathway in apoptosis of tumor cells.

Gastrointestinal stromal tumor: a rare abdominal tumor

Gastrointestinal stromal tumors (GISTs) are rare abdominal tumors which arise from the interstitial cells of Cajal in the gastrointestinal tract. Gastric GISTs are the most commonly seen GIST tumors and may grow to a very large size. They are often associated with abdominal pain, anorexia and weight loss. Most of them can be detected by CT. These tumors have been found to harbor mutations in CD117 which causes constitutional activation of the tyrosine kinase signaling pathway and is considered to be pathognomic. Tyrosine kinase inhibitors such as imatinib have revolutionized the treatment of these tumors, which are otherwise resistant to conventional chemotherapy and radiotherapy. Although surgical resection is the mainstay of treatment, tyrosine kinase inhibitors have been useful in prolonging the recurrence-free survival of these patients. Resistance to imatinib has been reported in GISTs with specific mutations. We present a case of gastric GIST which grew to a very large size and was associated with abdominal pain and weight loss. It was successfully resected and the patient was commenced on imatinib therapy.

Small submucosal tumors of the stomach: differentiation of gastric schwannoma from gastrointestinal stromal tumor with CT

Objective

To identify the CT features that help differentiate gastric schwannomas (GS) from small (5 cm or smaller) gastrointestinal stromal tumors (GIST) and to assess the growth rates of both tumors.

Materials and Methods

We included 16 small GSs and 56 GISTs located in the stomach. We evaluated the CT features including size, contour, surface pattern, margins, growth pattern, pattern and degree of contrast enhancement, and the presence of intralesional low attenuation area, hemorrhage, calcification, surface dimpling, fistula, perilesional lymph nodes (LNs), invasion to other organs, metastasis, ascites, and peritoneal seeding. We also estimated the tumor volume doubling time.

Results

Compared with GISTs, GSs more frequently demonstrated a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs (each p < 0.05). The intralesional low attenuation area was more common in GISTs than GSs (p < 0.05). Multivariate analyses indicated that a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs were statistically significant (p < 0.05). Tumor volume doubling times for GSs (mean, 1685.4 days) were significantly longer than that of GISTs (mean, 377.6 days) (p = 0.004).

Conclusion

Although small GSs and GISTs show similar imaging findings, GSs more frequently show an exophytic or mixed growth pattern, homogeneous enhancement pattern, perilesional LNs and grow slower than GISTs.

Prostate metastasis from gastric tumor: a report of one case

Here we report a case of prostate metastasis from gastric tumor in a 69-year-old man. Three years ago, he underwent gastrectomy for mucinous gastric carcinoma. He was admitted to our hospital due to micturition arduous and perineal pain. Ultrasound-guided biopsy of the prostate indicated prostate infiltration of the mucino-secretory adenocarcinoma. Immunohistochemistry indicated PSA negativity and positivity for CK20, CA19-9, and CEA. We arrived at the conclusion that we were dealing with the same neoplasia.

Relationship of cellular drug resistance to proportion of side population cells and expression of Mdr1 and ERCC1 in human gastric cell line SGC7901/OXA

AIM: To investigate the mechanism of acquired drug resistance in human gastric cancer cell line SGC7901/OXA.

METHODS: SGC7901/OXA cell line was obtained by exposure of SGC7901 cells to increasing doses of oxaliplatin (OXA). The parental cell line SGC7901 was used as a control. The reduced rate of cell growth, half maximal inhibitory concentration (IC50), and resistance index (RI) were measured by MTT assay and compared between the two groups of cells. The expression of multidrug resistance 1 (Mdr1) mRNA and excision repair cross-complementing group 1 (ERCC1) protein was detected by RT-PCR and Western blot, respectively. The proportion of side population (SP) cells was determined by flow cytometry.

RESULTS: The reduced rate of cell growth significantly decreased and IC50 increased (38.23 μmol/L vs 7.12 μmol/L) in SGC7901/OXA cells compared to parental SGC7901 cells. The RI was 5.37 in SGC7901/OXA cells. There was no significant difference in the relative expression level of Mdr1 mRNA (0.468 ± 0.147 vs 0.427 ± 0.136, P = 0.079) between the two groups. ERCC1 protein level was significantly higher in SGC7901/OXA cells than in SGC7901 cells. The proportion of SP cells was also significantly higher in SGC7901/OXA cells than in SGC7901 cells (6.1% vs 1.8%, P < 0.05).

CONCLUSION: SGC7901/OXA cells were more significantly resistant to OXA than SGC7901. The mechanism of acquired resistance of SGC7901/OXA cells may be associated with changes in ERCC1 protein expression and proportion of SP cells.

Genetic variations in the SMAD4 gene and gastric cancer susceptibility

AIM: To explore the association between mothers against decapentaplegic homolog 4 (SMAD4) gene polymorphisms and gastric cancer risk.

METHODS: Five tagging single nucleotide polymorphisms (tSNPs) in the SMAD4 gene were selected and genotyped in 322 gastric cancer cases and 351 cancer-free controls in a Chinese population by using the polymerase chain reactionrestriction fragment length polymorphism method. Immunohistochemistry was used to examine SMAD4 protein expression in 10 normal gastric tissues adjacent to tumors.

RESULTS: In the single-locus analysis, two significantly decreased risk polymorphisms for gastric cancer were observed: the SNP3 rs17663887 TC genotype (adjusted odds ratio = 0.38, 95% confidence interval: 0.21-0.71), compared with the wild-type TT genotype and the SNP5 rs12456284 GG genotype (0.31, 0.16-0.60), and with the wild-type AA genotype. In the combined analyses of these two tSNPs, the combined genotypes with 2-3 protective alleles (SNP3 C and SNP5 G allele) had a significantly decreased risk of gastric cancer (0.28, 0.16-0.49) than those with 0-1 protective allele. Furthermore, individuals with 0-1 protective allele had significantly decreased SMAD4 protein expression levels in the normal tissues adjacent to tumors than those with 2-3 protective alleles (P = 0.025).

CONCLUSION: These results suggest that genetic variants in the SMAD4 gene play a protective role in gastric cancer in a Chinese population.

Gastrointestinal symptomatic outcomes of laparoscopic and open gastrectomy

AIM: To compare the laparoscopic and the open gastrectomy approaches for short term morbidity, length of hospital stay and also long term gastrointestinal symptoms.

METHODS: Patients who have undergone gastrectomy had their medical records reviewed for demographic data, type of gastrectomy, short term morbidity, and length of hospital stay. Patients were contacted and asked to complete the Gastrointestinal Symptom Rating Scale (GSRS). The GSRS measures three domains of GI symptoms: Dyspepsia Syndrome (DS) for the foregut (best score 0, worse score 15), indigestion syndrome (IS) for the midgut (best score 0, worse score 12), and bowel dysfunction syndrome (BDS) for the hindgut (best score 0, worse score 16). Statistical analysis was done using the Mann-Whitney U-test.

RESULTS: We had complete data on 32 patients: 7 laparoscopic and 25 open. Of these, 25 had a gastroenteric anastomosis and 6 did not. The table shows the results as medians with interquartile range. Laparoscopic gastrectomy had a better score than open gastrectomy in the DS domain (0 vs 1, P = 0.02), while gastrectomy without anastomosis had a better score than gastrectomy with anastomosis in the IS domain (0 vs 1, P = 0.05).

CONCLUSION: Patients have little adverse gastrointestinal symptoms and preserve good gastrointestinal function after undergoing any type of gastrectomy. Laparoscopic approach had better dyspepsia and foregut symptoms. Performing an anastomosis led to mild adverse midgut and indigestion effects

OB glue paste technique for establishing nude mouse human gastric cancer orthotopic transplantation models

AIM: To establish nude mouse human gastric cancer orthotopic transplantation models using OB glue paste technique.

METHODS: Using OB glue paste technique, orthotopic transplantation models were established by implanting SGC-7901 and MKN-45 human gastric cancer cell strains into the gastric wall of nude mice. Biological features, growth of the implanted tumors, the success rate of transplantation and the rate of auto-metastasis of the two models were observed.

RESULTS: The success rates of orthotopic transplan-tation of the two models were 94.20% and 96%. The rates of hepatic metastasis, pulmonary metastasis, peritoneal metastasis, lymphocytic metastasis and splenic metastasis were 42.13% and 94.20%, 48.43% and 57.97%, 30.83% and 36.96%, 67.30% and 84.06%, and 59.75% and 10.53%, respectively. The occurrence of ascites was 47.80% and 36.96%.

CONCLUSION: OB glue paste technique is easy to follow. The biological behaviors of the nude mouse human gastric cancer orthotopic transplantation models established with this technique are similar to the natural processes of growth and metastasis of human gastric cancer, and, therefore, can be used as an ideal model for experimental research of proliferative metastasis of tumors.

Effect of arsenic trioxide on vascular endothelial cell proliferation and expression of vascular endothelial growth factor receptors Flt-1 and KDR in gastric cancer in nude mice

AIM: To investigate the effect of arsenic trioxide (As₂O₃) on expression of vascular endothelial growth factor receptor-1 (VEGFR-1, Flt-1) and VEGFR-2 (KDR) in human gastric tumor cells and proliferation of vascular endothelial cells.

METHODS: The solid tumor model was formed in nude mice with the gastric cancer cell line SGC-7901. The animals were treated with As₂O₃. Microvessel density (MVD) and expression of Flt-1 and KDR were detected by immunofluorescence laser confocal microscopy. SGC-7901 cells were treated respectively by exogenous recombinant human VEGF₁₆₅ or VEGF₁₆₅ + As₂O₃. Cell viability was measured by MTT assay. Cell viability of ECV304 cells was measured by MTT assay, and cell cycle and apoptosis were analyzed using flow cytometry.

RESULTS: The tumor growth inhibition was 30.33% and 50.85%, respectively, in mice treated with As₂O₃ 2.5 and 5 mg/kg. MVD was significantly lower in arsenic-treated mice than in the control group. The fluorescence intensity levels of Flt-1 and KDR were significantly less in the arsenic-treated mice than in the control group. VEGF₁₆₅ may accelerate growth of SGC7901 cells, but As₂O₃ may disturb the stimulating effect of VEGF₁₆₅. ECV304 cell growth was suppressed by 76.51%, 71.09% and 61.49% after 48 h treatment with As₂O₃ at 0.5, 2.5 and 5 μmol/L, respectively. Early apoptosis in the As₂O₃-treated mice was 2.88-5.1 times higher than that in the controls, and late apoptosis was 1.17-1.67 times higher than that in the controls.

CONCLUSION: Our results showed that As₂O₃ delays tumor growth, inhibits MVD, down-regulates Flt-1 and KDR expression, and disturbs the stimulating effect of VEGF₁₆₅ on the growth of SGC7901 cells. These results suggest that As₂O₃ might delay growth of gastric tumors through inhibiting the paracrine and autocrine pathways of VEGF/VEGFRs.

Clinicopathological significance of lymphangiogenesis in gastric cancer

AIM: To investigate the distribution patterns and proliferative activity of lymphatic vessels in gastric cancer and their relationship with lymphatic metastasis and clinicopathological features.

METHODS: Lymphatic microvessel density (LMVD) in tumorous areas of 56 cases of gastric cancer and non-tumorous areas of 12 corresponding normal tissues were immunohistochemically evaluated using a monoclonal antibody for podoplanin. Ki-67 protein expression of the lymphatic lining cells was simultaneously detected by double-labeling immunohistochemistry. The distribution patterns and the relationship between LMVD and clinicopathological features were analyzed.

RESULTS: Intratumoral lymphatic vessels, which were not often seen, had ill-defined lumina, while peritumoral lymphatic vessels had large and open lumina. LMVD at peritumoral regions were significantly more prevalent than at intratumoral areas and normal gastric submucosa (11.89 ± 3.95 vs 5.83 ± 3.26, 6.93 ± 1.32, P < 0.01, P < 0.05). The Ki-67 labeling index of the lymphatic lining cells at peritumoral regions was significantly higher than that in normal gastric submucosa and intratumoral regions (0.04 ± 0.02 vs 0, 0, both P < 0.05). LMVD protein expression significantly correlated with the differentiation of gastric cancer, lymphatic involvement by tumor cells, and lymph nodes metastasis (P < 0.05). The peritumoral Ki-67 labeling index of lymphatic lining cells was only significantly correlated with lymphatic involvement of tumor cells (P < 0.05).

CONCLUSION: Newly formed lymphatic vessels are found in gastric cancer, especially in peritumoral regions. Peritumoral lymphatic microvessels are the main route for lymphatic metastasis.

Coexistence of carcinoid, signet-ring cell carcinoma and heterotopic pancreas in stomach: a clinicopathological observation

AIM: To report a case with synchronous occurr-ence of carcinoid, signet-ring cell carcinoma (SRC) and heterotopic pancreas in stomach.

METHODS: One male patient aged 63 years old was diagnosed with coexistence of carcinoid, signet-ring cell carcinoma and heterotopic pancreas in stomach by gastroscopy and pathological examination. These three lesions were further observed by histopathological, histochemical and immunohistochemical approaches, with the related literatures reviewed.

RESULTS: Multiple foci of proliferative endocrine cells were found in lamina propria of the corpus, and carcinoid was found in corpus on the greater curve of the stomach, with muscularis mucosae involved. The tumor cells were strongly positive for neuron-specific enolase, synaptophysin and chromogranin A. An intramucosal SRC lesion was found in the lesser curve of corpus. Heterotopic pancreatic tissue was observed in muscularis propria of the antrum on the lesser curve, with hyperplasia of endocrine cells producing multiple pancreatic hormones.

CONCLUSION: Carcinoid in corpus of the greater curve and SRC in the lesser curve are independent lesions; the foci of endocrine cells in the muscularis propria and serosa are hyperplastic lesions from the heterotopic pancreatic tissue, rather than carcinoid dissemination.

Significance of Maspin, uPA and MMP-7 expression in human gastric carcinoma

AIM: To investigate the expression of Maspin, urokinase-type plasrninogen activator (uPA) uPA and Matrix metalloproteinase-7 (MMP-7) and their roles in the tumorigenesis and progre-ssion of gastric cancer.

METHODS: Immunohistochemistry SP method was used to detect the expression of Maspin, uPA and MMP-7 in tissues from gastric adenocarcinoma (n = 30), signet-ring cell carcinoma (n = 30), and normal gastric mucosa (n = 20).

RESULTS: The positive rates of Maspin, uPA and MMP-7 were 50%, 70% and 80%, respectively, in gastric adenocarcinoma, and they were 46.7%, 76.7% and 90%, respectively, in signet-ring cell carcinoma. However, the positive rates of Maspin, uPA, and MMP-7 were 90%, 35%, and 30%, respectively, in normal gastric mucosa. Maspin, uPA, and MMP-7 expression were significantly different between tissues from carcinoma and normal mucosa (P < 0.05 or P < 0.01). Maspin expression was significantly related to the depth of invasion and lymph node metastasis, but not to tumor size and TNM staging. The expression of uPA and MMP-7 were markedly related to the depth of invasion, lymph node metastasis and TNM staging, but not to tumor size. Maspin expression had a negative correlation with uPA and MMP-7 (P = 0.012, r = -0.322; P = 0.008, r = -0.341), while uPA expression had a positive correlation with MMP-7 (P = 0.034, r = 0.274).

CONCLUSION: Down-regulated expression of Maspin and up-regulated expression of uPA and MMP-7 play important roles in the invasion and metastasis of gastric carcinoma. They may serve as effective markers of reflecting the biopathological behaviors of gastric carcinoma.