The current state of diagnosis and treatment for early gastric cancer. Diagn Ther Endosc. 2013;2013:241320. [PMID: 23533320 PMCID: PMC3600289 DOI: 10.1155/2013/241320]

Clinical outcome of non-curative endoscopic submucosal dissection for early gastric cancer

Background

Early gastric cancer (EGC) is defined as cancer cells confined to the mucosal or submucosal layer, irrespective of size or presence of lymph node metastasis. The recent EGC endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) guidelines (2021 Japan Gastroenterological Endoscopy Society (JGES) guidelines, 2nd edition) revised the concept from "endoscopic curative/non-curative resection" (NCR) to "endoscopic curability (eCura)". Under this, eCuraA and eCuraB signify curative resections (CRs), while eCuraC (including eCuraC-1 and eCura-C2) indicate NCRs. This study retrospectively analyzes clinical and pathological data from EGC patients who underwent endoscopic resection, assessing the long-term clinical outcomes in a substantial cohort after undergoing NCR.

Methods

We retrospectively analyzed clinical and pathological data from 443 EGC patients, encompassing 478 lesions, who received endoscopic treatment. The long-term clinical outcomes of patients who underwent NCR were statistically evaluated. Characteristics of the NCR group were compared with those of the surgical group, employing single- and multi-factor logistic regression analyses to identify risk factors that necessitate further surgical intervention. Prognostically, the Kaplan-Meier method and Log-Rank test determined the impact of risk factors on recurrence-free survival post-surgery in NCR patients. Differences were assessed using a method incorporating statistically significant differences in the multi-factor Cox regression analysis, evaluating the hazard ratio (HR) for disease recurrence following NCR.

Results

In this study, 443 EGC cases were pathologically diagnosed, comprising a total of 478 lesions. Of these, 127 cases underwent non-curative endoscopic resection, resulting in a NCR rate of 24.4%. Long-term follow-up was achieved for 117 (92.12%) patients. The metastasis/recurrence rate at 6 months stood at 23.1%. Multivariate Cox regression analysis identified lesion size ≥2.0 and <3 cm [P=0.02, HR =0.12, 95% confidence interval (CI): 0.02-0.67], presence of ulceration (P=0.03, HR =5.48, 95% CI: 1.23-24.33), lymphatic invasion (P=0.05, HR =17.51, 95% CI: 1.07-286.23), positive vertical margins (P=0.09, HR =3.77, 95% CI: 0.81-17.53), and flat macroscopic morphology (P=0.048, HR =4.8, 95% CI: 1.01-22.73) as independent risk factors for recurrence-free survival post non-curative endoscopic resection in EGC patients.

Conclusions

The recurrence/metastasis rate in patients who underwent NCR is notably higher compared to the control group. Significant prognostic risk factors include tumor size ≥2.0 and <3 cm, positive vertical margins, lymphatic invasion, and flat type (one of pathological gross classification). Patients in the eCuraC-2 category of NCR should consider further surgical intervention. The necessity for additional surgical intervention in these patients warrants further investigation.

Absence of the Nonextension Sign as a Marker for Endoscopic Submucosal Dissection Suitability

Early gastric cancer is defined as gastric cancer confined to the mucosa or submucosa, irrespective of lymph node metastasis. Endoscopic submucosal dissection is a standard treatment of early gastric cancer. The nonextension sign consists of a protrusion of the surrounding mucosa into the lumen, resembling a trapezoidal shape. This phenomenon occurs when massive submucosal invasion by a cancer increases the thickness and rigidity of the gastric wall and may be useful to differentiate between mucosal or microinvasive submucosal and invasive submucosal cancers. Our case demonstrates the usefulness of the absence of the conventional endoscopic nonextension sign as a marker to decide the adequate approach for mucosal lesions.

Non-exposed endoscopic wall-inversion surgery with one-step nucleic acid amplification for early gastrointestinal tumors: Personal experience and literature review

BACKGROUND

Laparoscopic and endoscopic cooperative surgery is a safe, organ-sparing surgery that achieves full-thickness resection with adequate margins. Recent studies have demonstrated the safety and efficacy of these procedures. However, these techniques are limited by the exposure of the tumor and mucosa to the peritoneal cavity, which could lead to viable cancer cell seeding and the spillage of gastric juice or enteric liquids into the peritoneal cavity. Non-exposed endoscopic wall-inversion surgery (NEWS) is highly accurate in determining the resection margins to prevent intraperitoneal contamination because the tumor is inverted into the visceral lumen instead of the peritoneal cavity. Accurate intraoperative assessment of the nodal status could allow stratification of the extent of resection. One-step nucleic acid amplification (OSNA) can provide a rapid method of evaluating nodal tissue, whilst near-infrared laparoscopy together with indocyanine green can identify relevant nodal tissue intraoperatively.

AIM

To determine the safety and feasibility of NEWS in early gastric and colon cancers and of adding rapid intraoperative lymph node (LN) assessment with OSNA.

METHODS

The patient-based experiential portion of our investigations was conducted at the General and Oncological Surgery Unit of the St. Giuseppe Moscati Hospital (Avellino, Italy). Patients with early-stage gastric or colon cancer (diagnosed via endoscopy, endoscopic ultrasound, and computed tomography) were included. All lesions were treated by NEWS procedure with intraoperative OSNA assay between January 2022 and October 2022. LNs were examined intraoperatively with OSNA and postoperatively with conventional histology. We analyzed patient demographics, lesion features, histopathological diagnoses, R0 resection (negative margins) status, adverse events, and follow-up results. Data were collected prospectively and analyzed retrospectively.

RESULTS

A total of 10 patients (5 males and 5 females) with an average age of 70.4 ± 4.5 years (range: 62-78 years) were enrolled in this study. Five patients were diagnosed with gastric cancer. The remaining 5 patients were diagnosed with early-stage colon cancer. The mean tumor diameter was 23.8 ± 11.6 mm (range: 15-36 mm). The NEWS procedure was successful in all cases. The mean procedure time was 111.5 ± 10.7 min (range: 80-145 min). The OSNA assay revealed no LN metastases in any patients. Histologically complete resection (R0) was achieved in 9 patients (90.0%). There was no recurrence during the follow-up period.

CONCLUSION

NEWS combined with sentinel LN biopsy and OSNA assay is an effective and safe technique for the removal of selected early gastric and colon cancers in which it is not possible to adopt conventional endoscopic resection techniques. This procedure allows clinicians to acquire additional information on the LN status intraoperatively.

AI-assisted identification of intrapapillary capillary loops in magnification endoscopy for diagnosing early-stage esophageal squamous cell carcinoma: a preliminary study

Esophageal squamous cell carcinoma (ESCC) is one of the most common histological types of esophageal cancers. It can seriously affect public health, particularly in Eastern Asia. Early diagnosis and effective therapy of ESCC can significantly help improve patient prognoses. The visualization of intrapapillary capillary loops (IPCLs) under magnification endoscopy (ME) can greatly support the identification of ESCC occurrences by endoscopists. This paper proposes an artificial-intelligence-assisted endoscopic diagnosis approach using deep learning for localizing and identifying IPCLs to diagnose early-stage ESCC. An improved Faster region-based convolutional network (R-CNN) with a polarized self-attention (PSA)-HRNetV2p backbone was employed to automatically detect IPCLs in ME images. In our study, 2887 ME with blue laser imaging (ME-BLI) images of 246 patients and 493 ME with narrow-band imaging (ME-NBI) images of 81 patients were collected from multiple hospitals and used to train and test our detection model. The ME-NBI images were used as the external testing set to verify the generalizability of the model. The experimental evaluation revealed that the proposed method achieved a recall of 79.25%, precision of 75.54%, F1-score of 0.764 and mean average precision (mAP) of 74.95%. Our method outperformed other existing approaches in our evaluation. It can effectively improve the accuracy of ESCC detection and provide a useful adjunct to the assessment of early-stage ESCC for endoscopists.

Ornithine Decarboxylase in Gastric Epithelial Cells Promotes the Immunopathogenesis of Helicobacter pylori Infection

Colonization by Helicobacter pylori is associated with gastric diseases, ranging from superficial gastritis to more severe pathologies, including intestinal metaplasia and adenocarcinoma. The interplay of the host response and the pathogen affect the outcome of disease. One major component of the mucosal response to H. pylori is the activation of a strong but inefficient immune response that fails to control the infection and frequently causes tissue damage. We have shown that polyamines can regulate H. pylori-induced inflammation. Chemical inhibition of ornithine decarboxylase (ODC), which generates the polyamine putrescine from l-ornithine, reduces gastritis in mice and adenocarcinoma incidence in gerbils infected with H. pylori However, we have also demonstrated that Odc deletion in myeloid cells enhances M1 macrophage activation and gastritis. Here we used a genetic approach to assess the specific role of gastric epithelial ODC during H. pylori infection. Specific deletion of the gene encoding for ODC in gastric epithelial cells reduces gastritis, attenuates epithelial proliferation, alters the metabolome, and downregulates the expression of immune mediators induced by H. pylori Inhibition of ODC activity or ODC knockdown in human gastric epithelial cells dampens H. pylori-induced NF-κB activation, CXCL8 mRNA expression, and IL-8 production. Chronic inflammation is a major risk factor for the progression to more severe pathologies associated with H. pylori infection, and we now show that epithelial ODC plays an important role in mediating this inflammatory response.

Nomograms Involving HER2 for Predicting Lymph Node Metastasis in Early Gastric Cancer

Objective: We aimed to establish a nomogram for predicting lymph node metastasis in early gastric cancer (EGC) involving human epidermal growth factor receptor 2 (HER2).

Methods: We collected clinicopathological data of patients with EGC who underwent radical gastrectomy and D2 lymphadenectomy at Ruijin Hospital, Shanghai Jiao Tong University School of Medicine between January 2012 and August 2018. Univariate and multivariate logistic regression analysis were used to examine the relationship between lymph node metastasis and clinicopathological features. A nomogram was constructed based on a multivariate prediction model. Internal validation from the training set was performed using receiver operating characteristic (ROC) and calibration plots to evaluate discrimination and calibration, respectively. External validation from the validation set was utilized to examine the external validity of the prediction model using the ROC plot. A decision curve analysis was used to evaluate the benefit of the treatment.

Results: Among 1,212 patients with EGC, 210 (17.32%) presented with lymph node metastasis. Multivariable analysis showed that age, tumor size, submucosal invasion, histological subtype, and HER2 positivity were independent risk factors for lymph node metastasis in EGC. The area under the ROC curve of the model was 0.760 (95% CI: 0.719–0.800) in the training set (n = 794) and 0.771 (95% CI: 0.714–0.828) in the validation set (n = 418). A predictive nomogram was constructed based on a multivariable prediction model. The decision curve showed that using the prediction model to guide treatment had a higher net benefit than using endoscopic submucosal dissection (ESD) absolute criteria over a range of threshold probabilities.

Conclusion: A clinical prediction model and an effective nomogram with an integrated HER2 status were used to predict EGC lymph node metastasis with better accuracy and clinical performance.

ANALYSIS OF EXPRESSION OF MIRNA AND MRNA IN THE CELLULAR MATERIAL OF THE STOMACH LINING OBTAINED BY ESOPHAGOGASTRODUODENOSCOPY IN ORDER TO DETECT DYSPLASIA AND STOMACH CANCER

miRNA and mRNA are highly specific molecular markers, with their own unique expression profile for each type of tissue. They can become a valuable tool in clinical practice in addition to routine esophagogastroduodenoscopy.Purpose. To study the prospects of using a classifier based on miRNA and mRNA profiling in cytological samples for detecting dysplasia and stomach cancer, as well as to compare the obtained data with the results of profiling of 7 miRNAs used for the analysis of both histological and cytological material.Materials and methods. The study included 221 cytological preparations: 108 samples of adenocarcinoma, 27 samples of dysplasia, 86 samples of normal mucosa. The expression level of miRNA-145-5p, -150-5p, -21,-20a, -31-5p, -34a-5p, -375, -125b, -196b, -106b and mRNA of the following genes: TERT, CDKN2A, CKS2, FN1, was determined using real-time reverse transcription polymerase chain reaction. Quantitative comparison of two independent samples for was performed using the Mann-Whitney test. The samples were stratified into different groups using the C5.0 algorithm.Results: when examining cytological samples in cases of miRNA-125b, 145, -196b, -21, -375 and TERT, СKS2, FN1 mRNA, there was achieved a high level of significance of differences in the cancer/norm group; miRNA-375 and FN1 mRNA in the cancer/dysplasia group and miRNA-145, -196b, -20a, and СKS2, TERT mRNA in the norm/dysplasia groups. When comparing the results for the 7 miRNAs that were used to analyze both histological and cytological material, several differences was noted.Conclusion. The practical use of miRNA and mRNA expression (in cytological material data mining technology does not allow differentiating dysplasia and cancer but can help in identifying "high-risk patients" who should repeat esophagogastroduodenoscopy with multifocal forceps biopsy, with mandatory molecular genetic research.

KLK6 mediates stemness and metabolism of gastric carcinoma cells via the PI3K/AKT/mTOR signaling pathway

Gastric cancer is a common tumor of the digestive system, which can occur in any part of the stomach. Kallikrein 6 (KLK6) is a trypsin-like serine protease and has been found to be involved in extracellular matrix remodeling, tumor invasion and nervous system plasticity. Our previous study reported that KLK6 suppressed HGC-27 gastric cancer cell growth by inhibiting epithelial-mesenchymal transition; however, the mechanism of action underlying the effect of KLK6 still remains unclear. The aim of the present study was to investigate the effect and the underlying mechanism of KLK6 on stem cell-like properties and metabolism in gastric carcinoma cells. The HGC-27 cell line was transfected with KLK6 overexpression (OV-KLK6) and interference (short hairpin-KLK6) vectors, then the transfection efficiency was confirmed using western blot analysis and reverse transcription-quantitative PCR. The percentage of CD133⁺ and CD44⁺ cells was detected using flow cytometry, while the protein expression levels of the stem-associated genes, Nanog, Oct-4, SOX2 and Notch1, the metabolic markers, hexokinase (HK)1, HK2, GLUT1, and the proteins within the PI3K signaling pathway, phosphorylated (p)-PI3K, p-AKT and p-mTOR, were determined using western blot analysis. Biochemical kits were used to measure ATP production, lactic acid content and glucose uptake. A tumorigenicity assay was performed with nude mice to detect gastric tumor volume, and the protein expression level of Oct-4, Nanog, HK1, HK2 and GLUT1, and the mRNA expression level of KLK6 was also determined in gastric tumor tissues of mice. Compared with that in the control group, KLK6 protein and mRNA expression levels were significantly decreased in the four sh-RNA groups (P<0.05). Among them, sh-RNA-3 induced the lowest KLK6 expression and was used to silence KLK6 in subsequent experiments. Compared with that in the control and negative control groups, the percentage of CD133⁺ and CD44⁺ cells, the protein expression level of Oct-4, Nanog, HK1, HK2, GLUT1, p-PI3K, p-AKT and p-mTOR, and ATP content, lactic acid production, glucose uptake and gastric tumor volume were significantly decreased by sh-KLK6 (P<0.05), whereas KLK6 overexpression induced the opposite effect (P<0.05). In conclusion, KLK6 modulated stemness properties and cell metabolic profile in gastric carcinoma cells and the mechanism may be associated with the PI3K/AKT/mTOR signaling pathway.

Differentially expressed genes PCCA, ECHS1, and HADH are potential prognostic biomarkers for gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors in the world. As far as we know, no biomarker has been widely accepted for early diagnosis and prognosis prediction of GC. The purpose of this study is to find potential biomarkers to predict the prognosis of GC. The differentially expressed gene (DEG) was analyzed from GSE93774. Enrichr was used to analyze the gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, the enrichment of transcription factors (TF), miRNA, and kinase. GO analysis showed DEGs was enriched in the process of amino acid metabolism. Pathway results showed DEGs was mainly enriched in cell cycle. Propionyl CoA carboxylase alpha (PCCA), Enoyl coenzyme A hydratase short chain 1 (ECHS1), and 3-hydroxyacyl-CoA dehydrogenase (HADH) have prognostic value in patients with GC. ECHS1 and HADH genes were significantly associated with disease-free survival. There was a significant correlation between PCCA and overall survival rate. The results of this study suggest that PCCA, ECHS1, and HADH may be new biomarkers for predicting the prognosis of GC.

Expression and Role of Dickkopf-1 (Dkk1) in Tumors: From the Cells to the Patients

Dickkopf-1 (Dkk1) is a secretory antagonist of the classical Wnt signaling pathway. Many studies have reported that Dkk1 is abnormally expressed in tumor cells, and abnormal expression of Dkk1 can inhibit cell proliferation or induce apoptosis through pro-apoptotic factors, However, due to the differences in tumor environment and the complex regulatory mechanisms in different tumors, Dkk1 has different effects on the progression of different tumors. In many tumors, high expression of Dkk1 may promote tumor metastasis. However, Dkk1, which is highly expressed in other tumors, can inhibit tumor invasion and metastasis. More and more evidence shows that Dkk1 plays a complex and different role in tumor occurrence, development and metastasis in different tumor environments and through a variety of complex regulatory mechanisms. Therefore, Dkk1 may not only be a useful biomarker of metastasis, but also a target for studying the metabolic mechanism of tumor cells and treating tumors in many tumor types. Therefore, this article reviews the research progress on the expression, mechanism and function of Dkk1 in different tumors, and at the same time, based on the public database data, we made a further analysis of the expression of Dkk1 in different tumors.

Clinico-pathologic determinants of non-e-curative outcome following en-bloc endoscopic submucosal dissection in patients with early gastric neoplasia

Background

Endoscopic submucosal dissection (ESD) is gaining enormous popularity in the treatment of early gastric cancers (EGCs) in many institutions across the world. However, appropriate selection of candidates for endoscopic resection is crucial to sufficiently mitigate non-e-curative (NEC) resection. This study aims at identifying the various clinico-pathologic factors that independently predict the NEC outcome and depth of submucosal invasion following ESD procedure in patients with EGC.

Methods

Multiple logistic regression analysis was applied to investigate factors that independently predict both non-curability phenomenon and the level of submucosal invasion in patients with early gastric neoplasia. Statistical Packages for the Social Sciences version 23 was used for analysis.

Results

A total of 153 patients (162 EGC lesions) underwent en-bloc ESD after which the rate of complete resection and non-e-curative outcome were 95% and 22.2%, correspondingly. Multivariate analysis depicted that tumor location in the upper two third of stomach (odds ratio [OR], 5.46; 95% confidence interval [95% CI], 1.65–18.12; p = 0.006), tumor size > 2 cm (OR, 7.63; 95% CI, 2.29–25.42; p = 0.001), histologically undifferentiated tumor (OR, 15.54; 95% CI, 1.65–146.22; p = 0.001), and tumors with 0-IIa/0-IIc or their mixed variants with predominant 0-IIa/0-IIc (OR, 9.77; 95% CI, 1.23–77.65; p = 0.031) were all independent predictors of NEC resection for early gastric tumors. Additionally, location in the upper two third of the stomach (OR, 8.88; 95% CI, 2.90–27.17; p < 0.001), ulcerated lesions (OR, 3.70; 95% CI, 1.15–11.90; p = 0.028), lesions with > 2 cm (OR, 2.94; 95% CI, 1.08–8.02; p = 0.036) and those with poor differentiation (OR, 6.51; 95% CI, 2.23–18.98; p = 0.001) were found to have significant association with submucosal invasion.

Conclusions

Tumors located in the upper two third of the stomach having a larger size (> 2 cm), poor histo-differentiation and a gross type of 0-IIa/0-IIc or their mixed variants with predominant 0-IIa/0-IIc were significantly associated with a risk of NEC after ESD procedure. Thus, early gastric tumors displaying these features need to be handled carefully during endoscopic resection. Our findings may shed light on the pre-procedural detection of clinicopathologic factors that determine non-e-curability in patients with EGC.

Screening for gastric cancer in China: Advances, challenges and visions

Gastric cancer (GC) is one of the major cancers in China and all over the world. Most GCs are diagnosed at an advanced stage with unfavorable prognosis. Along with some other countries, China has developed the government-funded national screening programs for GC and other major cancers. GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs (Japan and Korea) and in studies based on selected Chinese populations. The screening of GC relies mostly on gastroendoscopy, the accuracy, reliability and safety of which have been indicated by previous studies. However, considering its invasive screening approach, requirements on skilled endoscopists and pathologists, and a high cost, developing noninvasive methods to amend endoscopic screening would be highly needed. Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen, gastrin, and Helicobacter pylori antibodies has been proposed for risk stratification, seeking to narrow down the high-risk populations for further endoscopy. Despite all the achievements of endoscopic screening, evidence on appropriate screening age, intervals for repeated screening, novel biomarkers promoting precision prevention, and health economics need to be accumulated to inform policymakers on endoscopic screening in China. With the guide of Health China 2030 Planning Outline, we have golden opportunities to promote prevention and control of GC. In this review, we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening, aiming for featuring the latest advances and key challenges, and illustrating future visions of GC screening.

LOW-GRADE DYSPLASIA, ENDOSCOPIC PREDICTORS, MANAGEMENT TACTICS

Almost all East Asian strains and 60% of Western H. pylori strains are of cagA +. The infected patients develop a more pronounced inflammation with ulceration of stomach, and also are under a higher risk of development of cancer.Objective: to improve the informative value of dysplasia diagnosis by combining white light endoscopy with chromoscopy, supplemented by target brush biopsy with cytological examination.Methods and materials: for the period from 2016 to 2018, the study included 41 patients undergoing examination and treatment of chronic gastritis. The analyzed cases included 16 (39%) men and 25 (61%) women. The age of the patients ranged from 19 to 86 years. All patients underwent esophagogastroduodenoscopy, chromoendoscopy with 0.5% methylene blue, brush biopsy (scraping with a nylon brush). At least two brush preparations were obtained: body of the stomach, antrum, scraping was also made on the surface of erosions and areas of atypical structure of the epithelium. Brush preparations were sent for cytological examination. Results: esophagogastroduodenoscopy revealed erosions in 37 (90.2%) patients, in 6 cases (14.6%) among them spontaneous bleeding was determined. In 23 (56%) patients visual signs of atrophic gastritis were noted. Cylindrical epithelium of the intestinal type was revealed in 25 patients (61%) using methylene blue.The cytological examination of the brush preparation showed proliferation of the integumentary epithelium with signs of mild dysplasia in all cases, intestinal metaplasia was revealed in 27 patients (65.8%), H. Pylori was confirmed in 38 patients (92.6%).Conclusion: chromoscopy and brush biopsy are simple and affordable methods, and their integration into routine endoscopy increases the informative value of the study, namely, allows detection of precancerous lesions of mucosa.

Deep learning in gastric tissue diseases: a systematic review

Background

In recent years, deep learning has gained remarkable attention in medical image analysis due to its capacity to provide results comparable to specialists and, in some cases, surpass them. Despite the emergence of deep learning research on gastric tissues diseases, few intensive reviews are addressing this topic.

Method

We performed a systematic review related to applications of deep learning in gastric tissue disease analysis by digital histology, endoscopy and radiology images.

Conclusions

This review highlighted the high potential and shortcomings in deep learning research studies applied to gastric cancer, ulcer, gastritis and non-malignant diseases. Our results demonstrate the effectiveness of gastric tissue analysis by deep learning applications. Moreover, we also identified gaps of evaluation metrics, and image collection availability, therefore, impacting experimental reproducibility.

Stomach cancer in young people - a diagnostic and therapeutic problem

INTRODUCTION

According to statistics, gastric cancer remains one of the most common causes of death due to neoplastic disease in the world's population. It is a common conception that this type of cancer mostly affects people in their fifth or sixth decade of life. So, when it comes to young people, for example in their twenties or early thirties, who present to a doctor with symptoms suggesting a cancer of the gastrointestinal tract, these are quite often ignored because of their young age.

AIM

In this study we at The Second Department of General and Gastroenterological Surgery of the Medical University of Białystok, Poland decided to enlighten the problem of stomach cancer in people under 40 years old as a cause of death and complications most likely because of an incorrect diagnosis at the beginning of therapy.

MATERIAL AND METHODS

Major analysis involved 350 cases of gastrointestinal tumours treated surgically, of which 14 cases (7 men and 7 women) were patients aged 18-39 years diagnosed with different stages of gastric cancer.

RESULTS

Statistical analysis has shown that gastric cancer in women occurred much earlier than in men, and the average survival time was 16 months after the surgery.

CONCLUSIONS

Because of the false suggestion that gastric cancer affects mostly older people, there is a risk of ignoring the symptoms in young people and finding advanced neoplastic lesions at the time of diagnosis, which has a negative effect on long-term treatment results.

Autologous tumor‑derived microvesicles influence gene expression profiles and enhance protumorigenic chemotactic potential, signal transduction and cellular respiration in gastric cancer cells

Tumor‑derived microvesicles (TMVs) interact with a variety of different cell types within the immune system, including lymphocytes, monocytes, dendritic cells and tumor cells that they have originated from. In the present study, the effects of autologous‑TMVs (auto‑TMVs) on gene expression, chemotaxis, intercellular signaling and cellular metabolism were examined in cells of the gastric cancer (GC) cell line 1415 (GC1415). The effects of auto‑TMVs on mRNA gene expression in GC1415 cells were assessed using pathway‑focused PCR arrays. A chemotaxis assay was performed using the HoloMonitor M4 System. Signaling pathways were evaluated using western blot analysis, and cellular respiration was measured using the Seahorse XF Cell Mito Stress Test. Exposure of the GC1415 cells to auto‑TMVs led to the overexpression (75 genes) and underexpression (96 genes) of genes that are associated with signal transduction, metabolism, chemotaxis, angiogenesis and metastasis. The auto‑TMVs were indicated to induce chemotaxis and activate the PI3K/AKT signaling pathway in GC1415 cells. However, the MAPK/ERK signaling pathway was not indicated to be activated. Furthermore, studies on cellular respiration in GC1415 cells exposed to auto‑TMVs demonstrated a metabolic shift to glycolysis. The results of the current study thus indicate that auto‑TMVs may exert an effect on tumor cell function.

More Frequent Follow-up CT Scans in Postsurgical Resection Patients Than in Postendoscopic Resection Patients of Early Gastric Cancers: Impracticality of CTs for Mucosal Cancer

RATIONALE AND OBJECTIVES

The aim of this study was to compare the utility and timing of computed tomography (CT) in the detection of recurrent tumors between patients after surgical and endoscopic resections for early gastric cancer (EGC).

MATERIALS AND METHODS

A total of 670 patients after surgical (n = 535) and endoscopic (n = 135) resections for EGC between 2007 and 2009 were enrolled. The mean numbers of CT and endoscopy between both treatment groups were compared. The mean and cumulative dose length products of CT examinations were calculated. The modality that detected recurrence was compared between the two groups using the Pearson chi-square test.

RESULTS

The mean interval of CT was significantly shorter and the mean number of CTs was significantly larger in the surgical resection group than in the endoscopic resection group. All 34 gastric recurrences were diagnosed by endoscopy. All seven extragastric recurrences occurred in patients treated for EGC with submucosal invasion. Six extragastric recurrences were detected by CT out of a total of 5417 CT scans. The average cumulative dose length product was significantly higher in the surgical group than in the endoscopic resection group (P = 0.004).

CONCLUSION

Follow-up CTs were performed more frequently in patients after surgical resection than in patients after endoscopic resection of EGCs. However, CT scans were not effective in detecting recurrent tumors after either treatment methods, especially for patients treated for mucosal gastric cancer.

Sentinel node biospy using intravital blue dye: An useful technique for identification of skip metastases in gastric cancer

As the lymph node status remains the main prognostic factor of gastric cancer (GC), several lymph node-based staging systems have been recently proposed for an appropriate postoperative therapy. The identification of sentinel lymph nodes (SLNs) might improve the postoperative protocols. The aim of this study was to present our experience in detecting SLNs in GC using methylene blue dye.We have performed an observational study and retrospectively analyzed all of the consecutive cases of GC operated by the same surgical team and managed by the same pathologists during 2013 to 2015. In all of the cases SLN status was determined using the methylene blue that was intraoperatively administered in the peritumoral subserosal tissue. All blue colored nodes were histopathologically examined. In the node negative cases immunohistochemical stains using AE1/AE3 keratin were performed.The blue SLNs were identified in 48 out of the 50 cases included in the study, with a 96% sensitivity and 87.50% specificity. From the 48 cases, 34 (70.83%) presented positive SLNs; in the other 14 cases the SLNs were negative (29.17%). False negativity was observed in 6 of the 14 cases. In 2 of the cases the false negativity of the group 20 was induced by the anthracotic pigment. In other 2 false negative cases, although no regional metastases were founded, sentinel skip metastases in the group 8 and 15, respectively, were identified.Mapping of the SLNs is a simple and cheap method that might improve the accuracy of LN-based staging of patients with GC and favor identification of skip metastases.

The incidence of lymph node metastasis in submucosal early gastric cancer according to the expanded criteria: a systematic review

BACKGROUND

For successful endoscopic treatment of early gastric cancer (EGC), absolute criteria for a curative en bloc resection were initially established to include predominantly differentiated mucosal lesions ≤ 2 cm in diameter without ulceration. These indications were subsequently expanded to include larger, ulcerated, and predominantly undifferentiated mucosal lesions. In addition, differentiated type adenocarcinomas ≤ 3 cm with slight submucosal invasion of < 500 µm (pT1b1) are regarded as "curative" under the expanded criteria. However, data derived from studies of surgical specimens in patients with pT1b1 EGC have yielded varying rates of lymph node metastasis (LNM).

METHOD

A systemic review was conducted using the pooled analysis to calculate the incidence of LNM in pT1b1 EGC, and to investigate whether using a cut-off value of < 300 µm would decrease the risk of LNM in patients with submucosal EGC.

RESULTS

Nineteen articles were included. 1507 patients with pT1b1 EGC met the expanded indications. The incidence of LNM was 3% (45 out of 1507 patients). In a subgroup analysis of three studies, there was no significant difference in the LNM between pT1b EGC < 300 µm and < 500 µm [3/121(2.5%) vs. 5/180 (2.8%)] (OR 0.89, 95% CI 0.22-3.54).

CONCLUSION

Overall, expanding the indications for endoscopic resection of EGC to include lesions ≤ 3 cm T1b1 is associated with a potential risk of LNM of 3%. In countries outside of Japan, we found a slightly higher risk of LNM (4.0%). These estimates of LNM should be incorporated into decisions regarding further management of patients with EGC ≤ 3 cm who are found to have slight submucosal invasion (< 500 µm) in an ESD specimen. Standardization of specimen handling and histological evaluation is essential if the Japanese results of endoscopic treatment for EGC are to be successfully applied in other parts of the world.

Laparoscopic and endoscopic cooperative surgery for gastric tumors: Perspective for actual practice and oncological benefits

Laparoscopic and endoscopic cooperative surgery (LECS) is a surgical technique that combines laparoscopic partial gastrectomy and endoscopic submucosal dissection. LECS requires close collaboration between skilled laparoscopic surgeons and experienced endoscopists. For successful LECS, experience alone is not sufficient. Instead, familiarity with the characteristics of both laparoscopic surgery and endoscopic intervention is necessary to overcome various technical problems. LECS was developed mainly as a treatment for gastric submucosal tumors without epithelial lesions, including gastrointestinal stromal tumors (GISTs). Local gastric wall dissection without lymphadenectomy is adequate for the treatment of gastric GISTs. Compared with conventional simple wedge resection with a linear stapler, LECS can provide both optimal surgical margins and oncological benefit that result in functional preservation of the residual stomach. As technical characteristics, however, classic LECS involves intentional opening of the gastric wall, resulting in a risk of tumor dissemination with contamination by gastric juice. Therefore, several modified LECS techniques have been developed to avoid even subtle tumor exposure. Furthermore, LECS for early gastric cancer has been attempted according to the concept of sentinel lymph node dissection. LECS is a prospective treatment for GISTs and might become a future therapeutic option even for early gastric cancer. Interventional endoscopists and laparoscopic surgeons collaboratively explore curative resection. Simultaneous intraluminal approach with endoscopy allows surgeons to optimizes the resection area. LECS, not simple wedge resection, achieves minimally invasive treatment and allows for oncologically precise resection. We herein present detailed tips and pitfalls of LECS and discuss various technical considerations.

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.

Prognostic value of Dickkopf-1 and ß-catenin expression in advanced gastric cancer

Background

Dickkopf-1 (DKK1) is a Wnt/ß-catenin pathway antagonist related to gastric cancer (GC) carcinogenesis. However, the prognostic role of combined DKK1 and ß-catenin expression in advanced GC (AGC) is not clear.

Methods

In total, 158 patients with AGC who underwent gastric resection were enrolled in this study. DKK1 and ß-catenin expression was evaluated in whole tumor sections by immunohistochemistry.

Results

DKK1 expression was high in 73 (46.2%) patients, while ß-catenin expression was positive in 51 (32.3%) patients. The expression of DKK1 was positively correlated with that of ß-catenin (P < 0.001). The combined expression of DKK1 and ß-catenin was significantly associated with high N stage (N2 and N3) (P = 0.042). In addition, patients with high DKK expression demonstrated poorer overall (OS) (P < 0.001) and disease-free survival (DFS) (P = 0.001). However, there were no differences between high DKK1 expression with ß-catenin positivity and high DKK1 expression with ß-catenin negativity (OS, P = 0.379: DFS, P = 0.255). Multivariate analysis revealed that high DKK1 alone or high DKK1 with ß-catenin positivity were independent prognostic factors for both OS (high DKK1: hazard ratio [HR], 2.130; 95% confidence interval [CI]; 1.370–3.312, P = 0.001; high DKK1 with ß-catenin positivity: HR, 2.140; 95% CI, 1.343–3.409: P = 0.001) and DFS (high DKK1: HR, 2.092; 95% CI, 1.180–3.708; P = 0.012; high DKK1 with ß-catenin positivity: HR, 2.357; 95% CI, 1.291–4.306; P = 0.005).

Conclusion

Our results indicate that high DKK1 expression regardless of ß-catenin positivity is a crucial prognostic factor for predicting tumor recurrence and survival in patients with resected AGC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4420-8) contains supplementary material, which is available to authorized users.

Occurrence of metachronous multiple primary cancers occurred in different parts of the stomach with 2 pathologic features: A case report

RATIONALE

With the increasing survival rate of gastric cancer, more multiple primary cancers (MPC) have been reported. However, few cases involve metachronous multiple primary cancers which both occurred in the stomach.

PATIENT CONCERNS

An 83-year-old Chinese male had been diagnosed with gastric cardia cancer and underwent proximal gastrectomy. The pathological result was gastric adenocarcinoma. 13 years later the patient's gastroscope result deteriorated. The biopsy of the antrum revealed dysplasia with doubtful focal cancerization.

DIAGNOSES

Metachronous multiple primary cancers in the stomach.

INTERVENTIONS

Endoscopic submucosal dissection (ESD) was performed. The pathological result showed an intra-mucosal signet-ring carcinoma.

OUTCOMES

After treatment, the patient is alive with good condition until now.

LESSONS

This is an unusual case of MPC with different pathological features in different parts of the same organ in an interval of more than ten years and undergoing different operations.

The incidence of lymph node metastasis in early gastric cancer according to the expanded criteria in comparison with the absolute criteria of the Japanese Gastric Cancer Association: a systematic review of the literature and meta-analysis

BACKGROUND AND AIMS

Japanese criteria for curative endoscopic resection of early gastric cancer initially included nonulcerated, well-differentiated mucosal lesions ≤2 cm in diameter, known as the absolute criteria. Subsequently, these indications were expanded to include larger, ulcerated, and undifferentiated mucosal lesions as well as differentiated lesions with slight submucosal invasion. Whether patients meeting the expanded criteria can be managed safely without gastrectomy and lymph node dissection has been controversial. The risk of lymph node metastasis (LNM) in patients who met the expanded criteria is a critical factor in determining the best course of management for these patients.

METHODS

We comprehensively searched main reference databases for studies that included patients who underwent gastrectomy and lymph node dissection for early gastric cancer. A meta-analysis was conducted by using the random effects model. Relative risk reduction was used to compare the incidence of LNM in patients meeting the absolute criteria as compared with those meeting the expanded criteria.

RESULTS

Twelve studies met the inclusion criteria, providing a total of 9798 patients. The incidence of LNM was 0.2% for patients who met the absolute criteria as compared with 0.7% for patients who met the expanded criteria. Analysis of the various components of the expanded criteria was conducted, revealing that the incidence of LNM for differentiated mucosal lesions ≤3 cm with ulceration and for differentiated mucosal lesions without ulceration, irrespective of size, was 16 of 2814 (0.57%), reference range (RR) 3.01; P = .02 and 8 of 3004 (0.27%), RR 1.69; P = .37, respectively, only marginally higher than the risk of LNM associated with the absolute criteria. In contrast, undifferentiated mucosal lesions ≤2 cm and differentiated lesions <3 cm with slight submucosal invasion had a significantly higher incidence of LNM in comparison with the absolute criteria (25/972 [2.6%], RR 6.79; P = .0004 and 8/315 [2.5%], RR 6.30; P = .004, respectively).

CONCLUSION

Overall, expanding the indication for endoscopic resection to include mucosal nonulcerated differentiated lesions irrespective of size and differentiated mucosal ulcerated lesions <3 cm is justified with minimal increased risk in comparison to the absolute criteria. However, expanding the indication for undifferentiated lesions ≤2 cm and differentiated lesions with slight submucosal invasion (T1b) should be balanced with the risks of surgery, given the increased risk of LNM in these patients.

Early Gastric Cancer: Clinical Behavior and Treatment Options. Results of an Italian Multicenter Study on Behalf of the Italian Gastric Cancer Research Group (GIRCG)

BACKGROUND

Early gastric cancer (EGC) generally has a good prognosis. However, the current definition of EGC includes various subgroups of patients with different pathological characteristics and different prognoses, some of whom have aggressive disease with a biological behavior similar to that of advanced carcinoma.

MATERIALS AND METHODS

We retrospectively evaluated 1,074 patients with EGC who had undergone surgery between 1982 and 2009. The cumulative incidence function of cancer-specific mortality and competing mortality were estimated using the Fine and Gray method.

RESULTS

The median follow-up period was 193 months (range 1-324). Five hundred and sixty-two (52.3%) patients died, 96 (8.9%) from EGC. The 5-, 10-, and 15-year cumulative incidence rates for mortality of all causes were 20.5% (95% confidence interval [CI] 18.0-22.9), 37.1% (95% CI 34.7-40.7), and 52.6% (95% CI 49.1-56.0), respectively; for cancer-specific mortality, 6.0% (95% CI 4.5-7.6), 9.9% (95% CI 7.9-11.9), and 11.1% (95% CI 8.8-13.3), respectively; and for mortality of other causes, 14.4% (95% CI 12.1-16.6), 27.2% (95% CI 24.2-30.2), and 41.5% (95% CI 38.1-43.3), respectively. A significant increase in the risk of cancer-specific mortality was observed for lesions >2 cm (adjusted hazard ratio [HR] = 1.44, 95% CI 1.07-1.94), Pen A-type disease (adjusted HR = 1.73, 95% CI 1.15-2.61), and node-positive cancers (adjusted HR = 2.28, 95% CI 1.61-3.21).

CONCLUSION

Patients with EGC with tumors >2 cm, Pen A-type disease according to Kodama, or lymph node metastases show a poorer prognosis and an increased risk of cancer-specific mortality.

IMPLICATIONS FOR PRACTICE

Early gastric cancer generally has a good prognosis, and some patients can be treated radically by endoscopic resection. However, the current definition of early gastric cancer includes subgroups of patients with an aggressive disease. In particular, patients with lymph node metastases and Pen A-type tumors according to Kodama's classification need a more invasive treatment, such as subtotal or total gastrectomy with an extended D2 lymphadenectomy, plus eventual adjuvant chemotherapy.

A prospective multi-institutional validity study to evaluate the accuracy of clinical diagnosis of pathological stage III gastric cancer (JCOG1302A)

BACKGROUND

Neoadjuvant chemotherapy (NAC) followed by radical surgery is a promising strategy to improve survival of patients with stage III gastric cancer, but is associated with the risk of preoperative overdiagnosis by which patients with early disease may receive unnecessary intensive chemotherapy.

METHODS

We assessed the validity of a preoperative diagnostic criterion in a prospective multicenter study. Patients with gastric cancer with a clinical diagnosis of T2/T3/T4, M0, except for diffuse large tumors and extensive bulky nodal disease, were eligible. Prospectively recorded clinical diagnoses (cT category, cN category) were compared with postoperative pathological diagnoses (pT category, pN category, and pathological stage). The primary endpoint was the proportion of pathological stage I tumors among those diagnosed as cT3/T4, which we expected to be 5% or less.

RESULTS

Data from 1260 patients enrolled from 53 institutions were analyzed. The proportion of pathological stage I tumors in those with a diagnosis of cT3/T4 (primary endpoint) was 12.3%, which was much higher than the prespecified value. The positive predictive value and the sensitivity for pathological stage III tumors were 43.6% and 87.8% respectively. The sensitivity and specificity of contrast-enhanced CT for lymph node metastasis were 62.5% and 65.7% respectively. After exploring several diagnostic criteria, we propose, for future NAC trials in Japan, a diagnosis of "cT3/T4 with cN1/N2/N3," by which inclusion of pathological stage I tumors was reduced to 6.5%, although its sensitivity for pathological stage III tumors decreased to 64.5%.

CONCLUSION

Clinical diagnosis of T3/T4 tumors was not an optimal criterion to select patients for intensive NAC trials because more than 10% of patients with pathological stage I disease were included. We propose the criterion "cT3/T4 and cN1/N2/N3" instead.

Immunohistochemical features and staging of early gastric cancer

INTRODUCTION

The aim of this study was to analyze the particularities of early gastric cancer (EGC) and their importance for staging, prognosis, and therapy.

MATERIAL AND METHODS

A total of 338 GCs diagnosed and surgically removed in three medical institutes from Eastern Europe were retrospectively examined, and the EGCs were further examined. Besides the demographic factors and tumor characteristics, immunostains were performed with E-cadherin, HER-2, p53, Ki67, MLH-1, MSH-2, COX-2, VEGF-A, CD31, and CD105.

RESULTS

From the 338 GCs, 29 were EGCs, the average being similar in Poland and Hungary (12.37% and 13.33% respectively) but lower in Romania (5.61%). The rate of lymph node metastases was 20.69% (n = 6). Two of the cases presented liver metastases, both of them having a multifocal aspect. In 1 of these cases, limited to the mucosa, intramural carcinomatosis of the lymph vessels was seen in submucosa, muscularis propria, and subserosa. COX-2 positivity was observed in 14 (48.72%) cases. COX-2 was directly correlated with microvessel density determined with CD31 (p < 0.001) and CD105 (p = 0.03). Same correlation with CD31 and CD105 was seen for HER-2 (p = 0.03 and p = 0.0007). The only negative independent prognostic factors for overall survival were tumor localization at the proximal stomach and male gender, regardless of age.

CONCLUSIONS

In EGCs, intramural carcinomatosis of the lymph vessels and multifocality should be separately described in every surgical pathology report, as indicators of aggressiveness. Microsatellite status, E-cadherin, HER-2, p53, and Ki67 do not have prognostic value in EGC, but the highly angiogenic pattern is a possible therapeutic target.

Detection of MET mRNA in gastric cancer in situ. Comparison with immunohistochemistry and sandwich immunoassays

Determination of predictive biomarkers by immunohistochemistry (IHC) relies on antibodies with high selectivity. RNA in situ hybridization (RNA ISH) may be used to confirm IHC and may potentially replace it if suitable antibodies are not available or are insufficiently selective to discriminate closely related protein isoforms. We validated RNA ISH as specificity control for IHC and as a potential alternative method for selecting patients for treatment with MET inhibitors. MET, the HGF receptor, is encoded by the MET proto-oncogene that may be activated by mutation or amplification. MET expression and activity were tested in a panel of control cell lines. MET could be detected in formalin fixed paraffin, embedded (FFPE) samples by IHC and RNA ISH, and this was confirmed by sandwich immunoassays of fresh frozen samples. Gastric cancer cell lines with high MET expression and phosphorylation of tyrosine-1349 respond to the MET inhibitor, BAY-853474. High expression and phosphorylation of MET is a predictive biomarker for response to MET inhibitors. We then analyzed MET expression and activity in a matched set of FFPE vs. fresh frozen tumor samples consisting of 20 cases of gastric cancer. Two of 20 clinical samples investigated exhibited high MET expression with RNA ISH and IHC. Both cases were shown by sandwich immunoassays to exhibits strong functional activity. Expression levels and functional activity in these two cases were in a range that predicted response to treatment. Our findings indicate that owing to its high selectivity, RNA ISH can be used to confirm findings obtained by IHC and potentially may replace IHC for certain targets if no suitable antibodies are available. RNA ISH is a valid platform for testing predictive biomarkers for patient selection.

Real-time Vessel Navigation Using Indocyanine Green Fluorescence during Robotic or Laparoscopic Gastrectomy for Gastric Cancer

Purpose

Identification of the infrapyloric artery (IPA) type is a key component of pylorus-preserving gastrectomy. As the indocyanine green (ICG) fluorescence technique is known to help visualize blood vessels and flow during reconstruction, we speculated that this emerging technique would be helpful in identifying the IPA type.

Materials and Methods

From August 2015 to February 2016, 20 patients who underwent robotic or laparoscopic gastrectomy were prospectively enrolled. After intravenous injection of approximately 3 mL of ICG (2.5 mg/mL), a near-infrared fluorescence apparatus was applied. The identified shape of the IPA was confirmed by examining the actual anatomy following infrapyloric dissection.

Results

The mean interval time between ICG injection and visualization of the artery was 22.2 seconds (range, 14–30 seconds), and the mean duration of the arterial phase was 16.1 seconds (range, 9–30 seconds). The overall positive predictive value (PPV) of ICG fluorescence in identifying the IPA type was 80% (16/20). The IPA type was incorrectly predicted in four patients, all of whom were obese with a body mass index (BMI) of more than 25 kg/m².

Conclusions

Our preliminary results indicate that intraoperative vascular imaging using the ICG fluorescence technique may be helpful for robotic or laparoscopic pylorus-preserving gastrectomy.

Endoscopic Management of Early Gastric Adenocarcinoma and Preinvasive Gastric Lesions

Early gastric cancer (ECG) can be difficult to diagnose endoscopically. Endoscopists should be familiar with subtle changes and endoscopic features of EGC. Chromoendoscopy and image-enhanced endoscopy improve diagnostic accuracy and facilitate endoscopic resection. Endoscopic submucosal dissection is a preferred endoscopic technique for resection of EGC and offers a comparable overall survival to surgical resection. Endoscopic management of benign gastric epithelial polyps (fundic gland polyps, hyperplastic polyps, and gastric adenoma) depends on patient symptomatology, patient's comorbidities (eg, familial syndromes), lesions' characteristics, and risk of malignant transformation. This article provides an overview of endoscopic management of EGC and common premalignant gastric lesions.

Association between polymorphisms of thymidylate synthase gene 5'- and 3'-UTR and gastric cancer risk: meta-analysis

Gastric cancer is the most common cancer and the most frequent cause of cancer death worldwide. Several studies have identified the role of thymidylate synthase (TS) 5′- and 3′-UTR and gastric cancer susceptibility; however, the results still remain inconclusive. The purpose of this meta-analysis was to reinvestigate this correlation. In the present study, online databases were searched to retrieve relevant articles published between January 2000 and 2016. The odds ratio (OR) and 95% confidence interval (CI) were employed to calculate the strength of association. Overall, a total of 13 articles were screened out, including 2382 gastric cancer patients and 3171 healthy controls. We found that polymorphisms of TS 5′-UTR 2R (double repeats)/3R (triple repeats) of a 28-bp sequence (11 articles) and 3′-UTR del6/ins6 (seven articles) were not significantly associated with increased risk of gastric cancer. Subgroup analysis by ethnicity showed that 2R allele and 2R/2R genotype in TS 5′-UTR were associated with gastric cancer susceptibility in Caucasian and African populations; del6 allele, del6/del6 and del6/ins6 genotypes were correlated with gastric cancer in Caucasian population. In conclusion, our result suggested that TS polymorphisms might be the risk factors for gastric cancer risk in Caucasian population, although this association needs further study, and future large-scale researches are still required.

Histomorphologic features of early gastric carcinoma treated by endoscopic submucosal dissection: relation to efficiency of endoscopic resection

OBJECTIVE

Early gastric cancer (EGC) is defined as cancer invasion confined to the mucosa or submucosa, irrespective of lymph node metastasis. Recently endoscopic submucosal dissection (ESD) has been widely accepted for the treatment for dysplasia and EGC without lymph node metastases. While the method has been advanced in Far East countries, ESD is still being developed in Europe and has not gained enough popularity although it has been recommended as the treatment of choice for superficial gastric neoplastic lesions by European Society of Gastrointestinal Endoscopy (ESGE) in 2015.

METHODS

The aim of the study was to perform a retrospective analysis of clinical and histomorphologic features of 58 cases of EGCs removed by ESD in a university hospital in Western Pomerania in Poland and to evaluate factors related to the efficiency of ESD resection.

RESULTS

With univariate analysis, indications for ESD with the highest R0 rate were found in EGCs limited to mucosa (T1a, small mucosal, M), without muscularis mucosa invasion, localised in the middle/lower part of stomach and intestinal type in histological examination. The R0 complete resection rate was significantly (p < 0.0001) lower for T1b than that for T1a tumours (21.4% vs. 100%). Tumours with submucosal involvement were associated with lower efficiency of ESD procedure.

CONCLUSIONS

Our data showed that in EGCs with favourable histomorphologic characteristics, ESD seemed to be a totally efficient and safe method of treatment in a European small-volume centre. R0 resection rate reached 81.1% of cases and median time of the ESD procedure was 61.5 min.

Sentinel Lymph Node Mapping In Gastric Cancer Surgery: Current Status

Lymphonodular metastases remain an important predictive and prognostic factor in gastric cancer development. The precise determination of the lymphonodular invasion stage can be made only by extended intraoperative lymphadenectomy and histopathological examination. But the main controversy is the usefulness of extended lymph dissection in early gastric cancer. This increases the duration of the surgery and the complications rate, and it is unnecessary without lymphonodular invasion. The identification of the sentinel lymph nodes has been successfully applied for some time in the precise detection of lymph nodes status in breast cancer, malignant melanoma and the use for gastric cancer patients has been a controversial issue. The good prognosis in early gastric cancer had been a surgery challenge, which led to the establishment of minimally invasive individualized treatment and acceptance of sentinel lymph node mapping. The dual-tracer method, submucosally administered endoscopically is also recommended in sentinel lymph node biopsy by laparoscopic approach. There are new sophisticated technologies for detecting sentinel lymph node such as: infrared ray endoscopy, florescence imaging and near-infrared technology, carbon nanoparticles, which will open new perspectives in sentinel lymph nodes mapping.

NOSE laparoscopic gastrectomies for early gastric cancer may reduce morbidity and hospital stay: early results from a prospective nonrandomized study

BACKGROUND

Natural orifice specimen extraction - NOSE laparoscopy is a promising technique that avoids mini-laparotomy, possibly reducing postoperative pain, wound infections and hospital stay. Recent systematic reviews have shown that postoperative morbidity associated with laparoscopically assisted gastrectomies is similar to that after open gastrectomies. More specifically, there is no difference in wound infection rate. The study objective was to evaluate whether postoperative morbidity and hospital stay may be reduced by transoral specimen extraction after laparoscopically assisted gastrectomy for early gastric cancer (EGC).

MATERIAL AND METHODS

A prospective, nonrandomized study was carried out starting in August 2012. Data from all patients operated on during the first year, with minimum 18 months follow-up, were collected to assess feasibility, oncologic results, postoperative morbidity, hospital stay and functional results. Overall, 14 patients were included and followed-up. After gastric resection, a 3 cm opening was created on the gastric stump, and the specimen, divided into three segments stitched one to each other, was sutured to the gastric tube and retrieved through the mouth.

RESULTS

Postoperative morbidity was 7.14% (1/14): one case of pneumonia. No wound infection occurred. The mean postoperative hospital stay was 4.7 ± 1.0 days.

CONCLUSIONS

NOSE laparoscopic subtotal gastrectomy is feasible and safe, with similar oncologic results as LAG, but decreased morbidity and hospital stay.

Pathophysiological and clinical aspects of gastric hyperplastic polyps

Gastric polyps become a major clinical problem because of high prevalence and tendency to malignant transformation of some of them. The development of gastric hyperplastic polyps results from excessive proliferation of foveolar cells accompanied by their increased exfoliation, and they are macroscopically indistinguishable from other polyps with lower or higher malignant potential. Panendoscopy allows detection and differentiation of gastric polyps, usually after obtaining histopathological biopsy specimens. Unremoved gastric hyperplastic polyps may enlarge and sometimes spontaneously undergo a sequential progression to cancer. For this reason, gastric hyperplastic polyps larger than 5 mm in size should be removed in one piece. After excision of polyps with atypical focal lesion, endoscopic surveillance is suggested depending on histopathological diagnosis and possibility of confirming the completeness of endoscopic resection. Because of the risk of cancer development also in gastric mucosa outside the polyp, neighboring fragments of gastric mucosa should undergo microscopic investigations. This procedure allows for identification of patients who can benefit most from oncological endoscopic surveillance. If Helicobacter pylori (H. pylori) infection of the gastric mucosa is confirmed, treatment strategies should include eradication of bacteria, which may prevent progression of intestinal metaplasia. The efficacy of H. pylori eradication should be checked 3-6 mo later.

Expression of Mismatch Repair Proteins in Early and Advanced Gastric Cancer in Poland

BACKGROUND Mutations in DNA of mismatch repair (MMR) genes result in failure to repair errors that occur during DNA replication in microsatellites, resulting in accumulation of frameshift mutations in these genes and leading to DNA mismatch replication errors and microsatellite instability. Gastric cancers (GCs) with high MSI (MSI-H) are a well-defined subset of carcinomas showing distinctive clinicopathological features. In this study we investigated the rate of MSI and the correlation between MSI status and clinicopathological features of GC. MATERIAL AND METHODS The study included 107 patients with GCs: 61 with advanced gastric cancers (AGC) and 46 with early gastric cancer (EGC). MSI deficiency in GCs was assessed by the immunohistochemical analysis of expression of MMR proteins - MLH1, MSH2, MSH6, and PMS2 - using formalin-fixed and paraffin-embedded tissue. RESULTS A total of 6 (5.6%) MSI-H were observed. The loss of MMR proteins expression was associated with the intestinal type of GC in Lauren classification, and tubular and papillary architecture in WHO classification. There was no statistically significant association between negative MMR expression and other selected clinical parameters: age, sex, tumor location, depth of invasion (EGC and AGC), lymph nodes status, presence of the ulceration, and lymphocytic infiltrate. CONCLUSIONS In the present era of personalized medicine, the histological type of GC and MMR proteins status in cancer cells are very important for the proper surveillance of patients with familial GC and sporadic GCs, as well as for selecting the proper follow-up and treatment. Larger collaborative studies are needed to verify the features of MSI-H GCs in Poland.

Intracorporeal reconstruction after laparoscopic pylorus-preserving gastrectomy for middle-third early gastric cancer: a hybrid technique using linear stapler and manual suturing

PURPOSE

Laparoscopy-assisted pylorus-preserving gastrectomy has been increasingly reported as a treatment for early gastric cancer located in the middle third of the stomach because of its low invasiveness and preservation of pyloric function. Advantages of a totally laparoscopic approach to distal gastrectomy, including small wound size, minimal invasiveness, and safe anastomosis, have been recently reported. Here, we introduce a new procedure for intracorporeal gastro-gastrostomy combined with totally laparoscopic pylorus-preserving gastrectomy (TLPPG).

METHODS

The stomach is transected after sufficient lymphadenectomy with preservation of infrapyloric vessels and vagal nerves. The proximal stomach is first transected near the Demel line, and the distal side is transected 4 to 5 cm from the pyloric ring. To create end-to-end gastro-gastrostomy, the posterior wall of the anastomosis is stapled with a linear stapler and the anterior wall is made by manual suturing intracorporeally. We retrospectively assessed the postoperative surgical outcomes via medical records. The primary endpoint in the present study is safety.

RESULTS

Sixteen patients underwent TLPPG with intracorporeal reconstruction. All procedures were successfully performed without any intraoperative complications. The mean operative time was 275 min, with mean blood loss of 21 g. With the exception of one patient who had gastric stasis, 15 patients were discharged uneventfully between postoperative days 8 and 11.

CONCLUSIONS

Our novel hybrid technique for totally intracorporeal end-to-end anastomosis was performed safely without mini-laparotomy. This technique requires prospective validation.

Upgrading the definition of early gastric cancer: better staging means more appropriate treatment

Since Murakami defined early gastric cancer (EGC) as a "carcinoma limited to the gastric mucosa and/or submucosa regardless of the lymph node status", several authors have focused on the most influential histopathological parameters for predicting the development of lymph node metastases by considering the lymph node status as an important prognostic factor. A few authors have also considered the depth of invasion as one of the keys to explaining the existence of subgroups of patients affected by EGC with poor prognoses. In any case, EGC is still considered an initial phase of tumor progression with good prognosis. The introduction of modern endoscopic devices has allowed a precise diagnosis of early lesions, which can lead to improved definitions of tumors that can be radically treated with endoscopic mucosal resection or endoscopic submucosal dissection (ESD). Given the widespread use of these techniques, the Japanese Gastric Cancer Association (JGCA) identified in 2011 the standard criteria that should exclude the presence of lymph node metastases. At that time, EGCs with nodal involvement should have been asserted as no longer fitting the definition of an early tumor. Some authors have also demonstrated that the morphological growth pattern of a tumor, according to Kodama's classification, is one of the most important prognostic factors, thereby suggesting the need to report it in histopathological drafts. Notwithstanding the acquired knowledge regarding the clinical behavior of EGC, Murakami's definition is still being used. This definition needs to be upgraded according to the modern staging of the disease so that the appropriate treatment would be selected.

Massive Endoscopic Screening for Esophageal and Gastric Cancers in a High-Risk Area of China

OBJECTIVE

This study aims to describe the findings from a massive endoscopic screening program in a high-risk area of China and to evaluate the prognosis of patients diagnosed through endoscopic screening compared with those diagnosed at usual hospital visits because of illness.

METHODS

In 2006, an early detection and treatment program was initiated in Yangzhong county, China. Local residents aged 40-69 years were eligible for free endoscopic screening. Endoscopic examination was performed with Lugol's iodine staining, followed by biopsies. Patients diagnosed with esophageal or gastric cancer were referred for treatment and followed to assess their long-term survival status.

RESULTS

From 2006 through 2012, we screened 12453 participants, including 5334 (42.8%) men and 7119 (57.2%) women. The average age was 52.8 ± 8.0 years. We detected 166 patients with upper digestive tract cancers, including 106 cancers in the esophagus (detection rate: 0.85%) and 60 cancers in the stomach (detection rate: 0.48%). Of these patients, 98.11% with esophageal cancer and 100% with gastric cancer were defined as at the early stage. In the process of follow-up, 17 patients died from cancer-related causes, and the median survival time was greater than 85 months. The overall survival rates for 1, 3 and 5 years were 98.0%, 90.0% and 89.0%, respectively. A significant positive effect was observed for the long-term survival of patients diagnosed through massive endoscopic screening.

CONCLUSIONS

In a high-risk population, massive endoscopic screening can identify early stage carcinoma of esophageal and gastric cancers and improve patients' prognosis through early detection and treatment.

Feasible endoscopic therapy for early gastric cancer

AIM

To analyze the relationship between lymph node metastasis and clinical pathology of early gastric cancer (EGC) in order to provide criteria for a feasible endoscopic therapy.

METHODS

Clinical data of the 525 EGC patients who underwent surgical operations between January 2009 and March 2014 in the West China Hospital of Sichuan University were analyzed retrospectively. Clinical pathological features were compared between different EGC patients with or without lymph node metastasis, and investigated by univariate and multivariate analyses for possible relationships with lymph node metastasis.

RESULTS

Of the 2913 patients who underwent gastrectomy with lymph node dissection, 529 cases were pathologically proven to be EGC and 525 cases were enrolled in this study, excluding 4 cases of gastric stump carcinoma. Among 233 patients with mucosal carcinoma, 43 (18.5%) had lymph node metastasis. Among 292 patients with submucosal carcinoma, 118 (40.4%) had lymph nodemetastasis. Univariate analysis showed that gender, tumor size, invasion depth, differentiation type and lymphatic involvement correlated with a high risk of lymph node metastasis. Multivariate analysis revealed that gender (OR = 1.649, 95%CI: 1.091-2.492, P = 0.018), tumor size (OR = 1.803, 95%CI: 1.201-2.706, P = 0.004), invasion depth (OR = 2.566, 95%CI: 1.671-3.941, P = 0.000), histological differentiation (OR = 2.621, 95%CI: 1.624-4.230, P = 0.000) and lymphatic involvement (OR = 3.505, 95%CI: 1.590-7.725, P = 0.002) were independent risk factors for lymph node metastasis. Comprehensive analysis showed that lymph node metastasis was absent in patients with tumor that was limited to the mucosa, size ≤ 2 cm, differentiated and without lymphatic involvement.

CONCLUSION

We propose an endoscopic therapy for EGC that is limited to the mucosa, size ≤ 2 cm, differentiated and without lymphatic involvement.

Aberrant metastatic behavior and particular features of early gastric cancer

In this paper, we have focused on the metastatic behavior of EGC and its particularities. The main factors that are currently considered as predictors of the metastatic behavior and that are used in the therapeutic decision (endoscopic resection vs surgical removal) are the tumor size (upper or bellow 2 cm), depth of infiltration, angiolymphatic invasion, the presence or absence of ulceration, and histologic type (undifferentiated vs differentiated carcinomas). However, most of the metastatic cases were published as case reports or case series. This is the reason why a proper estimation of metastatic risk in EGC is not well known. To date, 79 cases presenting bone metastases, three reports of brain metastases, and one EGC that was associated with skin metastasis were published. However, occult metastasis, lymph node micrometastasis, and skip metastasis can also occur and should be identified. Making a synthesis of the literature data that is correlated with our experience, we finally proposed the inclusion of the six Japanese subgrouping system, tumor size, angiolymphatic invasion, and micrometastasis as components of the pTNM staging system, which should be particularly adapted for EGC.

Cooperative laparoscopic endoscopic and hybrid laparoscopic surgery for upper gastrointestinal tumors: Current status

AIM: To investigate the cooperative laparoscopic and endoscopic techniques used for the resection of upper gastrointestinal tumors.

METHODS: A systematic research of the literature was performed in PubMed for English and French language articles about laparoscopic and endoscopic cooperative, combined, hybrid and rendezvous techniques. Only original studies using these techniques for the resection of early gastric cancer, benign tumors and gastrointestinal stromal tumors of the stomach and the duodenum were included. By excluding case series of less than 10 patients, 25 studies were identified. The study design, number of cases, tumor pathology size and location, the operative technique name, the endoscopy team and surgical team role, operative time, type of closure of visceral wall defect, blood loss, complications and length of hospital stay of these studies were evaluated. Additionally all cooperative techniques found were classified and are presented in a systematic approach.

RESULTS: The studies identified were case series and retrospective cohort studies. A total of 706 patients were operated on with a cooperative technique. The tumors resected were only gastrointestinal stromal tumors (GIST) in 4 studies, GIST and various benign submucosal tumors in 22 studies, early gastric cancer (pT1a and pT1b) in 6 studies and early duodenal cancer in 1 study. There was important heterogeneity between the studies. The operative techniques identified were: laparoscopic assisted endoscopic resection, endoscopic assisted wedge resection, endoscopic assisted transgastric and intragastric surgery, laparoscopic endoscopic cooperative surgery (LECS), laparoscopic assisted endoscopic full thickness resection (LAEFR), clean non exposure technique and non-exposed endoscopic wall-inversion surgery (NEWS). Each technique is illustrated with the roles of the endoscopic and laparoscopic teams; the indications, characteristics and short term results are described.

CONCLUSION: Along with the traditional cooperative techniques, new procedures like LECS, LAEFR and NEWS hold great promise for the future of minimally invasive oncologic procedures.

A comparison of endoscopic submucosal dissection (ESD) and radical surgery for early gastric cancer: a retrospective study

Background

Endoscopic submucosal dissection (ESD) has become one of the mainstays of treatment for early gastric cancer (EGC). Radical surgery is also a classical treatment method for EGC. There have been no systematic clinical studies of the curative effects and adverse events associated with ESD vs. radical surgery for EGC. This study investigated the therapeutic efficacy and safety of ESD and radical surgery for EGC.

Methods

Twenty-nine patients with EGC underwent ESD, and 59 underwent radical surgery at Weihai Municipal Hospital. The pathological characteristics, postoperative outcomes, hospital course, morbidity and mortality were retrospectively compared between the two groups.

Results

The oncological clearance was 93.1 % (27/29) in the ESD group. Postoperative delayed haemorrhage occurred in two patients. The hospital stay ranged from 10 to 23 days, and the average stay was 14.3 ± 3.7 days. The patients were followed-up for 1 to 5 years, with a mean follow-up of 26.9 ± 8.5 months. Regular endoscopic examinations showed that the wound had healed with no cancer recurrence in all of the patients. In the radical surgery group, the oncological clearance was 100 % (59/59). The hospital stay ranged from 11 to 55 days, and the average stay was 21.7 ± 9.3 days. The patients were followed-up for 1 to 3.7 years, with a mean follow-up of 22.3 ± 9.4 months. Nine patients developed complications, including acute postoperative adhesive ileus (1/59) and symptomatic residual gastritis (3/59). These complications were improved by an additional operation, drainage, gastrointestinal decompression and comprehensive therapy.

Conclusions

ESD achieved similar efficacy and had many advantages compared with radical surgery for the treatment of EGC.

Evaluation of Fibroblast Growth Factor Receptor 2 Expression, Heterogeneity and Clinical Significance in Gastric Cancer

BACKGROUND

We aimed to evaluate the protein and mRNA expression of fibroblast growth factor receptor 2 (FGFR2) by immunohistochemistry (IHC) and mRNA in situ hybridization (ISH), respectively, and to assess the heterogeneity of FGFR2 expression in gastric cancer (GC).

METHODS

A tissue microarray containing 362 surgically resected GC tissues and 135 matched metastatic lymph nodes was evaluated using FGFR2b IHC and FGFR2 ISH. FGFR2 fluorescence ISH was also performed in 188 cases.

RESULTS

All FGFR2-amplified cases (5 of 188) showed FGFR2b protein and FGFR2 mRNA overexpression (p < 0.001), and FGFR2 amplification was not identified in FGFR2b IHC- and FGFR2 mRNA ISH-negative cases. Kaplan-Meier survival analysis revealed that FGFR2b protein and FGFR2 mRNA overexpression was significantly associated with a poor overall survival (p < 0.001 and p = 0.012, respectively), and multivariate analyses showed that FGFR2 mRNA overexpression was an independent biomarker of a poor overall survival. Intratumoral heterogeneity of FGFR2b protein and FGFR2 mRNA overexpression was observed in 5 of 9 (55.5%) and 18 of 21 (85.7%) cases, respectively. Discordant FGFR2b and FGFR2 expression results between primary and matched metastatic lymph nodes were observed in 5 of 9 (55.5%) and 4 of 14 (28.6%) cases, respectively.

CONCLUSIONS

Intratumoral heterogeneity and discordant FGFR2b expression in primary tumors and metastatic lymph nodes are common in GC.

New Insights in Histogenetic Pathways of Gastric Cancer

The aim of this paper was to describe 3 possible histogenetic pathways for poorly cohesive (diffuse) carcinomas and 2 for intestinal-type gastric carcinomas (GCs), which might influence the behavior of GC. In the present observational study, 102 patients with early (n = 50) and advanced GCs (n = 52) were evaluated, and the histogenetic background was analyzed. All of the cases were sporadic GCs. For particular aspects, Maspin, E-cadherin, and SLUG immunostains were performed. For our final conclusions, the results were correlated with literature data. In early stages, poorly cohesive carcinomas can display 3 histogenetic pathways, with particular molecular behaviors: "carcinoma with intraepithelial pagetoid onset" (with or without a switch from E-cadherin to SLUG positivity), "carcinoma with early lymphatic invasion" (carcinoma limited to mucosa but with carcinomatosis of the lymph vessels from subjacent layers), and "microglandular-type poorly cohesive carcinoma" (the onset is similar with adenocarcinoma but abrupt dedifferentiation can be seen in the submucosa, with persistence of a dual component in the deep layers). The intestinal type carcinoma can be developed on the background of superficially located dysplasia ("classic adenocarcinoma") or in the submucosal heterotopic mucosa ("adenocarcinoma arising from the mucosal infolding in the submucosa"). Based on personal observations correlated with literature data, 5 histopathogenetic pathways are proposed with specific denominations. Each of them can partially explain the aberrant behavior of early gastric cancer.