Prognostic value of differentiation status in gastric cancer

Clinicopathological and prognostic significance of TIMP1 expression in gastric cancer: a systematic review and meta-analysis

BACKGROUND

The research on the associations between tissue inhibitors of metalloproteinase-1 (TIMP1) expression and the clinicopathological characteristics and prognosis of patients with gastric cancer (GC) have resulted in contradictory findings. Exploring the associations between TIMP1 and clinicopathological parameters and the prognosis of GC patients is essential.

METHODS

We searched the literature in the databases according to the inclusion and exclusion criteria. Hazard ratios (HRs), odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to evaluate the relationships between TIMP1 expression and the clinicopathological parameters and prognosis of GC patients.

RESULTS

Nine studies with 1,200 GC patients were included. Our results indicated that TIMP1 expression was not related to sex, age, TNM stage, depth of invasion, lymph node metastasis, or tumor size in GC patients. However, TIMP1 expression was associated with the differentiation of GC. Furthermore, TIMP1 expression was associated with poor prognosis in GC patients.

CONCLUSION

TIMP1 expression was related to tumor differentiation and poor prognosis but not sex, age, TNM stage, depth of invasion, lymph node metastasis or tumor size.

Machine learning to predict distant metastasis and prognostic analysis of moderately differentiated gastric adenocarcinoma patients: a novel focus on lymph node indicators

Background

Moderately differentiated gastric adenocarcinoma (MDGA) has a high risk of metastasis and individual variation, which strongly affects patient prognosis. Using large-scale datasets and machine learning algorithms for prediction can improve individualized treatment. The specific efficacy of several lymph node indicators in predicting distant metastasis (DM) and patient prognosis in MDGA remains obscure.

Methods

We collected data from MDGA patients from the SEER database from 2010 to 2019. Additionally, we collected data from MDGA patients in China. We used nine machine learning algorithms to predict DM. Subsequently, we used Cox regression analysis to determine the risk factors affecting overall survival (OS) and cancer-specific survival (CSS) in DM patients and constructed nomograms. Furthermore, we used logistic regression and Cox regression analyses to assess the specific impact of six lymph node indicators on DM incidence and patient prognosis.

Results

We collected data from 5,377 MDGA patients from the SEER database and 109 MDGC patients from hospitals. T stage, N stage, tumor size, primary site, number of positive lymph nodes, and chemotherapy were identified as independent risk factors for DM. The random forest prediction model had the best overall predictive performance (AUC = 0.919). T stage, primary site, chemotherapy, and the number of regional lymph nodes were identified as prognostic factors for OS. Moreover, T stage, number of regional lymph nodes, primary site, and chemotherapy were also influential factors for CSS. The nomograms showed good predictive value and stability in predicting the 1-, 3-, and 5-year OS and CSS in DM patients. Additionally, the log odds of a metastatic lymph node and the number of negative lymph nodes may be risk factors for DM, while the regional lymph node ratio and the number of regional lymph nodes are prognostic factors for OS.

Conclusion

The random forest prediction model accurately identified high-risk populations, and we established OS and CSS survival prediction models for MDGA patients with DM. Our hospital samples demonstrated different characteristics of lymph node indicators in terms of distant metastasis and prognosis.

[Gender medicine in diseases of the upper gastrointestinal tract]

Benign and malignant diseases of the upper gastrointestinal tract show gender-specific differences. The frequent gastroesophageal reflux disease is a prime example: men have an erosive reflux disease more often than women and are also younger at the time of onset. The rate of progression to a metaplastic Barrett's esophagus is also higher in men. In the case of achalasia, there are indications that surgical treatment by laparoscopic Heller's myotomy and semifundoplication 180° according to Dor leads to a markedly better improvement in the symptoms in women compared to men, although they showed a more pronounced dilation of the tubular esophagus. The female hormone status influences the localization and histopathology of adenocarcinoma of the esophagogastric junction and gastric carcinoma. Premenopausal and postmenopausal carcinomas differ significantly in women. In addition, high microsatellite instability (MSI high) is more frequent in women and is associated with a generally significantly better prognosis. The MSI high gastric carcinomas of women show better survival than MSI high carcinomas of men. The future inclusion of gender-specific aspects in studies of the upper gastrointestinal tract is desirable in order to generate adequate data and to enable differentiated treatment stratification in the future.

Predicting gastric cancer response to anti-HER2 therapy or anti-HER2 combined immunotherapy based on multi-modal data

The sole use of single modality data often fails to capture the complex heterogeneity among patients, including the variability in resistance to anti-HER2 therapy and outcomes of combined treatment regimens, for the treatment of HER2-positive gastric cancer (GC). This modality deficit has not been fully considered in many studies. Furthermore, the application of artificial intelligence in predicting the treatment response, particularly in complex diseases such as GC, is still in its infancy. Therefore, this study aimed to use a comprehensive analytic approach to accurately predict treatment responses to anti-HER2 therapy or anti-HER2 combined immunotherapy in patients with HER2-positive GC. We collected multi-modal data, comprising radiology, pathology, and clinical information from a cohort of 429 patients: 310 treated with anti-HER2 therapy and 119 treated with a combination of anti-HER2 and anti-PD-1/PD-L1 inhibitors immunotherapy. We introduced a deep learning model, called the Multi-Modal model (MuMo), that integrates these data to make precise treatment response predictions. MuMo achieved an area under the curve score of 0.821 for anti-HER2 therapy and 0.914 for combined immunotherapy. Moreover, patients classified as low-risk by MuMo exhibited significantly prolonged progression-free survival and overall survival (log-rank test, P < 0.05). These findings not only highlight the significance of multi-modal data analysis in enhancing treatment evaluation and personalized medicine for HER2-positive gastric cancer, but also the potential and clinical value of our model.

Long-term outcomes of endoscopic submucosal dissection for undifferentiated type early gastric cancer over 2 cm with R0 resection

BACKGROUND

Endoscopic submucosal dissection (ESD) for over 2 cm in size undifferentiated type (UD type) early gastric cancer (EGC) confined to the mucosa is not only challenging, but also long-term outcomes are not well known.

AIM

To evaluate the long-term outcomes of ESD done for UD type EGCs confined to the mucosa over 2 cm in size and compare the results with those where the lesions were less than 2 cm.

METHODS

143 patients with UD type EGC confirmed on histology after ESD at a tertiary hospital were reviewed. Cases with synchronous and metachronous lesions and a case with emergency surgery after ESD were excluded. A total of 137 cases were enrolled. 79 cases who underwent R0 resection were divided into 2 cm or less (group A) and over 2 cm (group B) in size.

RESULTS

Among 79 patients who underwent R0 resection, the number in group A and B were 51 and 28, respectively. The mean follow-up period (SD) was 79.71 ± 45.42 months. There was a local recurrence in group A (1/51, 2%) and group B (1/28, 3.6%) respectively. This patient in group A underwent surgery while the patient in group B underwent repeated ESD with no further recurrences in both patients. There was no regional lymph node metastasis, distant metastasis, and deaths in both groups. With R0 resection strategy for ESD on lesions over 2 cm, 20.4% (28/137) of patients were able to avoid surgery compared with expanded indication.

CONCLUSION

If R0 resection is achieved by ESD, UD type EGCs over 2 cm also showed good and similar clinical outcomes as compared to lesions less than 2 cm when followed for over 5 years. With R0 resection strategy, several patients can avoid surgery.

Prognostic relevance of the most predominant and least differentiated grades of gastric adenocarcinoma after curative gastrectomy

BACKGROUND

Prognostic relevance of differentiation grade has remained controversial in gastric adenocarcinoma (GAC) after curative resection.

METHODS

GAC patients who underwent curative gastrectomy were analyzed. Differentiation grade was evaluated according to either the most predominant or least differentiated component. Impacts of clinicopathologic parameters on postoperative recurrence and nodal metastasis were analyzed by the multivariate Cox regression analysis in pT1/2/3/4a and pT1b/2/3 GAC and by the logistic regression analysis in pT1b GAC, respectively.

RESULTS

154 patients with GAC, consisting of 34 pT1a (recurrence rate 0%), 45 pT1b (4.4%), 18 pT2 (22.2%), 40 pT3 (35.0%), and 17 pT4a (76.5%), were included. In pT1/2/3/4a GAC, recurrence was significantly associated with only depth of invasion (pT) and grade of venous invasion (VI), although either mode of differentiation grade was significantly associated with pT by the Spearman's rank correlation test. Next, given no recurrence in pT1a and high-grade histopathology in nearly all pT4a, pT1b/2/3 GAC was analyzed, revealing that recurrence was significantly associated with only VI grade and nodal metastasis. Finally, nodal metastasis was not found in any pT1a GAC, of which 44.1% was predominantly high-grade. In pT1b GAC, nodal metastasis was irrelevant to either mode of differentiation grade, tumor size, and ulceration status but was only associated with lymphatic invasion, suggesting that endoscopic resection of pT1 GAC with negative margin can be curative even with high-grade histopathology.

CONCLUSION

Either mode of differentiation grade revealed limited prognostic relevance after curative gastrectomy. Our results may warrant a controversy over current curability evaluation of endoscopic GAC resection.

Development and validation of a nomogram to predict cancer-specific survival of elderly patients with unresected gastric cancer who received chemotherapy

This investigation aimed to explore the prognostic factors in elderly patients with unresected gastric cancer (GC) who have received chemotherapy and to develop a nomogram for predicting their cancer-specific survival (CSS). Elderly gastric cancer patients who have received chemotherapy but no surgery in the Surveillance, Epidemiology, and End Results Database between 2004 and 2015 were included in this study. Cox analyses were conducted to identify prognostic factors, leading to the formulation of a nomogram. The nomogram was validated using receiver operating characteristic (ROC) and calibration curves. The findings elucidated six prognostic factors encompassing grade, histology, M stage, radiotherapy, tumor size, and T stage, culminating in the development of a nomogram. The ROC curve indicated that the area under curve of the nomogram used to predict CSS for 3, 4, and 5 years in the training queue as 0.689, 0.708, and 0.731, and in the validation queue, as 0.666, 0.693, and 0.708. The calibration curve indicated a high degree of consistency between actual and predicted CSS for 3, 4, and 5 years. This nomogram created to predict the CSS of elderly patients with unresected GC who have received chemotherapy could significantly enhance treatment accuracy.

Analysis of endoscopic and pathological features of 6961 cases of gastric cancer

Gastric cancer (GC) stage and tissue differentiation affect treatment efficacy and prognosis, highlighting the importance of understanding the risk factors that affect these parameters. Therefore, this study analyzed risk factors affecting the GC stage and differentiation and the relationships between the cancer site and the sex and age of the patient. We collected clinical data from 6961 patients with GC, including sex, age, endoscopic lesion location, and pathological differentiation. Patients were grouped based on GC stage (early or advanced), differentiation (well or poorly differentiated), and lesion site (upper stomach [cardia and fundus], middle stomach [gastric body], and lower stomach [gastric antrum]). Differences in sex, age, location, stage, and degree of differentiation were assessed based on these groupings. Univariate analysis revealed that the disease location and differentiation significantly differed based on the GC stage (P < 0.05), whereas sex, age, site, and stage significantly differed based on GC differentiation (P < 0.05). A multivariate analysis confirmed these factors as independent risk factors affecting GC. Moreover, lesion sites significantly differed between sexes (P < 0.05) and among age groups (P < 0.05). Although the effects of family history, lifestyle, and Helicobacter pylori infection status of the patients were not considered, this single-center retrospective study established independent risk factors for GC.Trial registration ChiCTR2200061989.

Establishment of Patient-Derived Organoids Using Ascitic or Pleural Fluid from Cancer Patients

PURPOSE

Patient-derived tumor cells can be a powerful resource for studying pathophysiological mechanisms and developing robust strategies for precision medicine. However, establishing organoids from patient-derived cells is challenging because of limited access to tissue specimens. Therefore, we aimed to establish organoids from malignant ascites and pleural effusions.

MATERIALS AND METHODS

Ascitic or pleural fluid from pancreatic, gastric, and breast cancer patients was collected and concentrated to culture tumor cells ex vivo. Organoids were considered to be successfully cultured when maintained for five or more passages. Immunohistochemical staining was performed to compare the molecular features, and drug sensitivity was assayed to analyze the clinical responses of original patients.

RESULTS

We collected 70 fluid samples from 58 patients (pancreatic cancer, n=39; gastric cancer, n=21; and breast cancer, n=10). The overall success rate was 40%; however, it differed with types of malignancy, with pancreatic, gastric, and breast cancers showing 48.7%, 33.3%, and 20%, respectively. Cytopathological results significantly differed between successful and failed cases (p=0.014). Immunohistochemical staining of breast cancer organoids showed molecular features identical to those of tumor tissues. In drug sensitivity assays, pancreatic cancer organoids recapitulated the clinical responses of the original patients.

CONCLUSION

Tumor organoids established from malignant ascites or pleural effusion of pancreatic, gastric, and breast cancers reflect the molecular characteristics and drug sensitivity profiles. Our organoid platform could be used as a testbed for patients with pleural and peritoneal metastases to guide precision oncology and drug discovery.

KLF5‑mediated expression of CARD11 promotes the progression of gastric cancer

Caspase recruitment domain-containing protein 11 (CARD11) has been reported as functioning in multiple types of cancers. In the present study, the role and mechanism of CARD11 in gastric cancer was investigated. First, CARD11 expression in gastric cancer tissues and the association of CARD11 with overall survival were analyzed by the encyclopedia of RNA interactomes database. CARD11 expression in gastric cancer cells was detected by western blotting and reverse transcription-quantitative PCR analyses. After CARD11 silencing, cell proliferation was evaluated by Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine staining and flow cytometry analysis. Wound healing and Transwell assays were used to measure the capacities of cell migration and invasion. Additionally, the expression levels of epithelial-mesenchymal transition (EMT)-related proteins and mTOR-related proteins were detected by western blot analysis. HumanTFDB predicted the binding of the transcription factor Krüppel-like factor 5 (KLF5) to the CARD11 promoter, which was confirmed by dual luciferase reporter and chromatin immunoprecipitation assays. To explore the regulatory effects between KLF5 and CARD11, KLF5 was overexpressed to perform the rescue experiments in gastric cancer cells with CARD11 silencing. Results revealed that CARD11 was highly expressed in gastric cancer and was associated with poor prognosis. CARD11 interference inhibited the proliferation of gastric cancer cells and induced cell cycle arrest. Additionally, CARD11 silencing suppressed the migration, invasion and EMT of gastric cancer cells, accompanied by upregulated E-cadherin expression and downregulated N-cadherin and vimentin expression. Moreover, the transcription factor KLF5 positively regulated the transcription of CARD11 in gastric cancer. KLF5 overexpression reversed the effects of interference of CARD11 expression in gastric cancer cells to promote their proliferation, migration, invasion and EMT. KLF5 overexpression also led to a reduction in cell cycle arrest. Finally, interference of CARD11 expression suppressed the mTOR pathway, which was activated by KLF5. In conclusion, KLF5-mediated CARD11 promoted the proliferation, migration and invasion of gastric cancer cells.

Development and validation of LightGBM algorithm for optimizing of Helicobacter pylori antibody during the minimum living guarantee crowd based gastric cancer screening program in Taizhou, China

Gastric cancer continues to be a significant health concern in China, with a high incidence rate. To mitigate its impact, early detection and treatment is key. However, conducting large-scale endoscopic gastric cancer screening is not feasible in China. Instead, a more appropriate approach would be to initially screen high-risk groups and follow up with endoscopic testing as needed. We conducted a study on 25,622 asymptomatic participants aged 45-70 years from a free gastric cancer screening program in the Taizhou city government's Minimum Living Guarantee Crowd (MLGC) initiative. Participants completed questionnaires, blood tests, and underwent gastrin-17 (G-17), pepsinogen I and II (PGI and PGII), and H. pylori IgG antibody (IgG) assessments. Using the light gradient boosting machine (lightGBM) algorithm, we developed a predictive model for gastric cancer risk. In the full model, F1 score was 2.66%, precision was 1.36%, and recall was 58.14%. In the high-risk model, F1 score was 2.51%, precision was 1.27%, and recall was 94.55%. Excluding IgG, the F1 score was 2.73%, precision was 1.40%, and recall was 68.62%. We conclude that H. pylori IgG appears to be able to be excluded from the prediction model without significantly affecting its performance, which is important from a health economic point of view. It suggests that screening indicators can be optimized, and expenditures reduced. These findings can have important implications for policymakers, as we can focus resources on other important aspects of gastric cancer prevention and control.

miR-548 predicts clinical prognosis and functions as a tumor promoter in gastric cancer

Numerous pieces of evidence have demonstrated the functional role of miR-548 in various cancers. The expression and function of miR-548 in gastric cancer were investigated in the present study. A total of 123 gastric cancer patients were included and provided paired gastric cancer tissues and matched normal tissues. RT-qPCR was used to detect the expression of miR-548. CCK8 assay was used to evaluate cell proliferation, and Transwell assay was applied to assess cell migration and invasion. The clinical significance of miR-548 was estimated by a series of statistical analyses. miR-548 was found to be upregulated in gastric cancer, which was associated with the lymph node metastasis and TNM stage of patients. Patients with relatively high miR-548 expression possessed bad survival. miR-548 was identified as a prognostic indicator of gastric cancer. miR-548 was also found to promote the proliferation, migration, and invasion of gastric cancer. Upregulated miR-548 was involved in the progression of gastric cancer and predicted the prognosis of patients. Inhibition of miR-548 might be a novel therapeutic strategy for gastric cancer.

Long-term survival outcome of locally advanced gastric cancer patients who achieved a pathological complete response to neoadjuvant chemotherapy

BACKGROUND

Long-term outcome of patients with locally advanced gastric cancer (LAGC) who achieved a pathological complete response (pCR) was scarcely discussed, and never had the factors affecting the prognosis of pCR patients been investigated.

METHODS

We retrospectively reviewed all patients who achieved a pCR to neoadjuvant chemotherapy (NAC) in Jinling Hospital. The 3- and 5-year overall survival (OS) and progression-free survival (PFS) were calculated with the Kaplan-Meier method. Meanwhile, univariate and multivariate COX regression analysis was applied to identify prognostic factors affecting patients' survival.

RESULTS

A total of 37 consecutive LAGC patients with pCR were included. The 3- and 5-year OS rates were 88.8% and 78.6%, and the 3- and 5-year PFS rates were 86.5% and 75.8%. In the multivariate COX model, NAC duration of more than 3 cycles (HR 0.11 [0.02-0.62], P = 0.013) and poorly differentiated tumor at diagnosis (HR 0.17 [0.03-0.95], P = 0.043) were detected as protective factors for patients OS. Whereas for PFS, NAC duration (HR 0.12 [0.02-0.67], P = 0.015) was the only protective factor confirmed, with tumor differentiation at diagnosis exhibiting marginal significance (HR 0.21 [0.04-1.09], P = 0.063).

CONCLUSIONS

Patients with LAGC who achieved a pCR displayed favorable long-term survival outcome, especially those with adequate cycles (≥ 3) of NAC. Besides, poor differentiation at diagnosis might also predict the better OS when pCR achieved.

Nomogram established using risk factors of early gastric cancer for predicting the lymph node metastasis

BACKGROUND

For the prognosis of patients with early gastric cancer (EGC), lymph node metastasis (LNM) plays a crucial role. A thorough and precise evaluation of the patient for LNM is now required.

AIM

To determine the factors influencing LNM and to construct a prediction model of LNM for EGC patients.

METHODS

Clinical information and pathology data of 2217 EGC patients downloaded from the Surveillance, Epidemiology, and End Results database were collected and analyzed. Based on a 7:3 ratio, 1550 people were categorized into training sets and 667 people were assigned to testing sets, randomly. Based on the factors influencing LNM determined by the training sets, the nomogram was drawn and verified.

RESULTS

Based on multivariate analysis, age at diagnosis, histology type, grade, T-stage, and size were risk factors of LNM for EGC. Besides, nomogram was drawn to predict the risk of LNM for EGC patients. Among the categorical variables, the effect of grade (well, moderate, and poor) was the most significant prognosis factor. For training sets and testing sets, respectively, area under the receiver-operating characteristic curve of nomograms were 0.751 [95% confidence interval (CI): 0.721-0.782] and 0.786 (95%CI: 0.742-0.830). In addition, the calibration curves showed that the prediction model of LNM had good consistency.

CONCLUSION

Age at diagnosis, histology type, grade, T-stage, and tumor size were independent variables for LNM in EGC. Based on the above risk factors, prediction model may offer some guiding implications for the choice of subsequent therapeutic approaches for EGC.

ISLR interacts with MGAT5 to promote the malignant progression of human gastric cancer AGS cells

Objectives

Gastric cancer is a common malignant tumor with high morbidity and mortality. The present study aimed to investigate the role of the immunoglobulin superfamily containing leucine-rich repeat (ISLR) gene in gastric cancer and examine whether ISLR could interact with N-acetylglucosaminyltransferase V (MGAT5) to affect the malignant progression of gastric cancer.

Materials and Methods

The expression of ISLR and MGAT5 in human normal gastric epithelial cells and human gastric cancer cells, and the transfection efficiency of ISLR interference plasmids and MGAT5 overexpression plasmids were all detected by reverse transcription-quantitative PCR (RT-qPCR) and western blot. The viability, proliferation, migration and invasion, and epithelial-mesenchymal transition (EMT) of gastric cancer cells after indicated transfection were detected by Cell counting kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) staining, wound healing assay, and transwell assay. The interaction between ISLR and MGAT5 was confirmed by co-immunoprecipitation. The expression of proteins related to migration, invasion, and EMT was detected by immunofluorescence and western blot.

Results

As a result, ISLR was highly expressed in gastric cancer and was associated with poor prognosis. Interference with ISLR inhibited the viability, proliferation, migration, invasion, and EMT of gastric cancer cells. ISLR interacted with MGAT5 in gastric cancer cells. MGAT5 overexpression weakened the effects of ISLR knockdown on suppressing the viability, proliferation, migration, invasion, and EMT of gastric cancer cells.

Conclusion

ISLR interacted with MGAT5 to promote the malignant progression of gastric cancer.

Are radiomic spleen features useful for assessing the differentiation status of advanced gastric cancer?

Background

The differentiation status of gastric cancer is related to clinical stage, treatment and prognosis. It is expected to establish a radiomic model based on the combination of gastric cancer and spleen to predict the differentiation degree of gastric cancer. Thus, we aim to determine whether radiomic spleen features can be used to distinguish advanced gastric cancer with varying states of differentiation.

Materials and methods

January 2019 to January 2021, we retrospectively analyzed 147 patients with advanced gastric cancer confirmed by pathology. The clinical data were reviewed and analyzed. Three radiomics predictive models were built from radiomics features based on gastric cancer (GC), spleen (SP) and combination of two organ position (GC+SP) images. Then, three Radscores (GC, SP and GC+SP) were obtained. A nomogram was developed to predict differentiation statue by incorporating GC+SP Radscore and clinical risk factors. The area under the curve (AUC) of operating characteristics (ROC) and calibration curves were assessed to evaluate the differential performance of radiomic models based on gastric cancer and spleen for advanced gastric cancer with different states of differentiation (poorly differentiated group and non- poorly differentiated group).

Results

There were 147 patients evaluated (mean age, 60 years ± 11SD, 111 men). Univariate and multivariate logistic analysis identified three clinical features (age, cTNM stage and CT attenuation of spleen arterial phase) were independent risk factors for the degree of differentiation of GC (p =0.004,0.000,0.020, respectively). The clinical radiomics (namely, GC+SP+Clin) model showed powerful prognostic ability in the training and test cohorts with AUCs of 0.97 and 0.91, respectively. The established model has the best clinical benefit in diagnosing GC differentiation.

Conclusion

By combining radiomic features (GC and spleen) with clinical risk factors, we develop a radiomic nomogram to predict differentiation status in patients with AGC, which can be used to guide treatment decisions.

Evaluation of Human Epidermal Growth Factor Receptor 2 Expression in Gastric and Gastroesophageal Cancers in Tanzania

CONTEXT.—

The incidence of human epidermal growth factor receptor 2 (HER2) positivity in gastric cancers differs widely across various populations and is unknown in many low-resource settings.

OBJECTIVE.—

To evaluate the rates of HER2 positivity in gastric and gastroesophageal adenocarcinoma at a national referral hospital in East Africa. We also assessed the association between HER2 overexpression and patient clinicopathologic characteristics.

DESIGN.—

A retrospective review of cases diagnosed as either gastric or gastroesophageal adenocarcinoma between 2013 and 2017 was performed at Muhimbili National Hospital in Dar es Salaam, Tanzania. Of 1205 specimens meeting inclusion criteria, stratified random sampling was conducted to select 150 cases for HER2 immunohistochemistry and clinicopathologic analysis.

RESULTS.—

The median age of patients was 56.5 years, with 65.3% (98 of 150) of the cohort composed of male patients, and 34.7% (52 of 150) of female patients. HER2 overexpression was identified in 6.0% (9 of 150) of cases. Approximately half of the tumors (51.3%; 77 of 150) were intestinal-type gastric adenocarcinoma, and 36.0% (54 of 150) were moderately differentiated. Intestinal-type (P = .01) and well-differentiated tumors (P = .001) were associated with HER2 overexpression.

CONCLUSIONS.—

HER2 overexpression was primarily seen in intestinal-type and well-differentiated tumors. Therefore, prioritizing HER2 testing for patients with intestinal-type, well-differentiated, or moderately differentiated gastric and gastroesophageal adenocarcinomas may be appropriate in Tanzania in efforts to allocate testing for patients who are most likely to benefit from trastuzumab therapy.

The Correlation of Ten Immune Checkpoint Gene Expressions and Their Association with Gastric Cancer Development

In the immunotherapy based on immune checkpoint inhibition (IC), additional ICs are being studied to increase its effectiveness. An almost unstudied feature is the possible co-expression of ICs, which can determine the therapeutic efficacy of their inhibition. For the selection of promising ICs, information on the association of their expression with cancer development may be essential. We have obtained data on the expression correlation of ADAM17, PVR, TDO2, CD274, CD276, CEACAM1, IDO1, LGALS3, LGALS9, and HHLA2 genes in gastric cancer (GC). All but one, TDO2, have other IC genes with co-expression at some stage. At the metastatic stage, the expression of the IDO1 does not correlate with any other gene. The correlations are positive, but the expressions of the CD276 and CEACAM1 genes are negatively correlated. The expression of TDO2 and LGALS3 is associated with GC metastasis. The expression of TDO2 four-fold higher in metastatic tumors than in non-metastatic tumors, but LGALS3 was two-fold lower. The differentiation is associated with IDO1. The revealed features of TDO2, with a significant increase in expression at the metastatic stage and the absence of other IC genes with correlated expression indicates that the prospect of inhibiting TDO2 in metastatic GC. IDO1 may be considered for inhibition in low-differentiated tumors.

Prognostic significance of tumor deposits in radically resected gastric cancer: a retrospective study of a cohort of 1915 Chinese individuals

BACKGROUND

Tumor deposits (TDs) have been identified as an independent prognostic factor in gastric cancer (GC). However, the associated clinicopathological factors and how to simply and reasonably incorporate TD into the TNM staging system remain undetermined. The aim of the current study was therefore to assess the significance of TD among radically resected GC patients.

METHODS

We retrospectively reviewed 1915 patients undergoing radical resection between 2007 and 2012. The patients were classified into two groups according to TD status (absent vs. present), and the clinicopathologic characteristics, DFS, and OS were compared. Associations of TD presence with other clinicopathologic factors were evaluated by logistic regression analysis. Univariate and multivariate Cox regression analyses were performed to determine the prognostic factors for DFS and OS in the primary cohort. Propensity score matching (PSM) was performed to reduce the possibility of selection bias according to the presence of TD. External validation of previously proposed modified staging systems incorporating TD was conducted.

RESULTS

The detection rate of TD was 10.5% (201/1915). The presence of TD was significantly related to unfavorable clinicopathologic variables, including advanced T and N categories. According to the multivariate Cox regression analysis, the presence of TD was identified as an independent prognostic factor for DFS and OS in the primary cohort (both P < 0.001). In the after-PSM cohort, TD presence also significantly shortened DFS and OS. In the external validation, one system that incorporated TD into the pTNM stage had the best performance.

CONCLUSIONS

The presence of TD was significantly associated with poor survival in radically resected GC patients. The incorporation of TD into the TNM staging system can further improve the predictive capability. A multicenter cohort with a large sample size is needed to determine the appropriate method of incorporation.

Interpretable tumor differentiation grade and microsatellite instability recognition in gastric cancer using deep learning

Gastric cancer possesses great histological and molecular diversity, which creates obstacles for rapid and efficient diagnoses. Classic diagnoses either depend on the pathologist's judgment, which relies heavily on subjective experience, or time-consuming molecular assays for subtype diagnosis. Here, we present a deep learning (DL) system to achieve interpretable tumor differentiation grade and microsatellite instability (MSI) recognition in gastric cancer directly using hematoxylin-eosin (HE) staining whole-slide images (WSIs). WSIs from 467 patients were divided into three cohorts: the training cohort with 348 annotated WSIs, the testing cohort with 88 annotated WSIs, and the integration testing cohort with 31 original WSIs without tumor contour annotation. First, the DL models comprehensibly achieved tumor differentiation recognition with an F1 values of 0.8615 and 0.8977 for poorly differentiated adenocarcinoma (PDA) and well-differentiated adenocarcinoma (WDA) classes. Its ability to extract pathological features about the glandular structure formation, which is the key to distinguishing between PDA and WDA, increased the interpretability of the DL models. Second, the DL models achieved MSI status recognition with a patient-level accuracy of 86.36% directly from HE-stained WSIs in the testing cohort. Finally, the integrated end-to-end system achieved patient-level MSI recognition from original HE staining WSIs with an accuracy of 83.87% in the integration testing cohort with no tumor contour annotation. The proposed system, therefore, demonstrated high accuracy and interpretability, which can potentially promote the implementation of artificial intelligence healthcare.

The Feasibility of Applying Artificial Intelligence to Gastrointestinal Endoscopy to Improve the Detection Rate of Early Gastric Cancer Screening

Convolutional neural networks in the field of artificial intelligence show great potential in image recognition. It assisted endoscopy to improve the detection rate of early gastric cancer. The 5-year survival rate for advanced gastric cancer is less than 30%, while the 5-year survival rate for early gastric cancer is more than 90%. Therefore, earlier screening for gastric cancer can lead to a better prognosis. However, the detection rate of early gastric cancer in China has been extremely low due to many factors, such as the presence of gastric cancer without obvious symptoms, difficulty identifying lesions by the naked eye, and a lack of experience among endoscopists. The introduction of artificial intelligence can help mitigate these shortcomings and greatly improve the accuracy of screening. According to relevant reports, the sensitivity and accuracy of artificial intelligence trained on deep cirrocumulus neural networks are better than those of endoscopists, and evaluations also take less time, which can greatly reduce the burden on endoscopists. In addition, artificial intelligence can also perform real-time detection and feedback on the inspection process of the endoscopist to standardize the operation of the endoscopist. AI has also shown great potential in training novice endoscopists. With the maturity of AI technology, AI has the ability to improve the detection rate of early gastric cancer in China and reduce the death rate of gastric cancer related diseases in China.

Subgingival Periopathogens Assessment and Clinical Periodontal Evaluation of Gastric Cancer Patients—A Cross Sectional Pilot Study

Oral microbiota have shown a higher bacterial diversity in patients with cancers of the digestive tract, with higher levels of periopathogens. Recent studies have shown that Fusobacterium links to gastro-intestinal neoplastic tissue and accelerates its progression, as well as worsening patient outcome. The present pilot study was carried out between February and December 2020 to evaluate the possible association between the abundance of some periopathogens (Fusobacterium nucleatum, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Treponema denticola and Tannerella forsythia) in subgingival plaque and periodontal status with characteristics of gastric cancer. The study was performed on a sample of 24 patients with gastric cancer from the 1st Department of Surgery and Department of Gastroenterology within the Clinical County Hospital of Emergency of Craiova, Romania. The patients’ oral cavity was examined, gingival crevicular samples were collected, and signs of periodontal disease were recorded. On the histopathological exam, the differentiation grade and size of the tumour were registered. Our results showed that, from the periopathogens studied, the most abundant bacteria were F. nucleatum followed by T. forsythia in all groups. In our present study, the strong correlation between tumour dimension and all periodontal parameters but also between tumour dimension and F. nucleatum could suggest a positive association between periodontal disease, tumoral growth and periopathogens implication in this process.

Deep learning model for diagnosing gastric mucosal lesions using endoscopic images: development, validation, and method comparison

BACKGROUND AND AIMS

Endoscopic differential diagnoses of gastric mucosal lesions (benign gastric ulcer, early gastric cancer [EGC], and advanced gastric cancer) remain challenging. We aimed to develop and validate convolutional neural network-based artificial intelligence (AI) models: lesion detection, differential diagnosis (AI-DDx), and invasion depth (AI-ID; pT1a vs pT1b among EGC) models.

METHODS

This study included 1366 consecutive patients with gastric mucosal lesions from 2 referral centers in Korea. One representative endoscopic image from each patient was used. Histologic diagnoses were set as the criterion standard. Performance of the AI-DDx (training/internal/external validation set, 1009/112/245) and AI-ID (training/internal/external validation set, 620/68/155) was compared with visual diagnoses by independent endoscopists (stratified by novice [<1 year of experience], intermediate [2-3 years of experience], and expert [>5 years of experience]) and EUS results, respectively.

RESULTS

The AI-DDx showed good diagnostic performance for both internal (area under the receiver operating characteristic curve [AUROC] = .86) and external validation (AUROC = .86). The performance of the AI-DDx was better than that of novice (AUROC = .82, P = .01) and intermediate endoscopists (AUROC = .84, P = .02) but was comparable with experts (AUROC = .89, P = .12) in the external validation set. The AI-ID showed a fair performance in both internal (AUROC = .78) and external validation sets (AUROC = .73), which were significantly better than EUS results performed by experts (internal validation, AUROC = .62; external validation, AUROC = .56; both P < .001).

CONCLUSIONS

The AI-DDx was comparable with experts and outperformed novice and intermediate endoscopists for the differential diagnosis of gastric mucosal lesions. The AI-ID performed better than EUS for evaluation of invasion depth.

TP53 Co-Mutational Features and NGS-Calibrated Immunohistochemistry Threshold in Gastric Cancer

Purpose

TP53 is the most frequently mutated gene in gastric cancer and it can be potentially used for gastric cancer diagnosis and screening. However, standardized clinical approaches that could accurately and cost-effectively detect TP53 mutations in gastric cancer are largely lagged behind.

Patients and Methods

We conducted next-generation sequencing (NGS) analysis of 425 cancer-related genes in 42 gastric cancer patients in our cohort. A 1313-patient cohort derived from the cBioPortal database was used for validation. We performed immunohistochemistry (IHC) staining with four commonly used p53 antibodies, and the NGS results were used as the gold standard to optimize the IHC threshold for each antibody.

Results

By NGS analysis, we found that around 80% of gastric cancer patients in our cohort harbored TP53 alterations. Genetic alterations of BRCA1/2 or KMT2B were mostly exclusive with TP53 mutations, so were the MSI status or low grade of tumors. These results were further validated using the data from cBioPortal. We then used the NGS-derived TP53 status to optimize four commonly used IHC antibodies for detecting TP53 mutations. We showed that all antibodies could achieve more than 93% accuracy when proper IHC positivity thresholds were used, especially for the SP5 antibody that could reach 100% sensitivity and specificity with the 20% threshold.

Conclusion

Our results indicated that exclusivity between TP53 and BRCA mutations could be potentially used as a cost-effective way to predict BRCA status. Also, setting proper IHC thresholds for each specific antibody is critical to accurately detect TP53 mutations and facilitate disease diagnosis.

Prognostic value of modified Lauren classification in gastric cancer

BACKGROUND

It remains controversial as to which pathological classification is most valuable in predicting the overall survival (OS) of patients with gastric cancer (GC).

AIM

To assess the prognostic performances of three pathological classifications in GC and develop a novel prognostic nomogram for individually predicting OS.

METHODS

Patients were identified from the Surveillance, Epidemiology, and End Results program. Univariate and multivariate analyses were performed to identify the independent prognostic factors. Model discrimination and model fitting were evaluated by receiver operating characteristic curves and Akaike information criteria. Decision curve analysis was performed to assess clinical usefulness. The independent prognostic factors identified by multivariate analysis were further applied to develop a novel prognostic nomogram.

RESULTS

A total of 2718 eligible GC patients were identified. The modified Lauren classification was identified as one of the independent prognostic factors for OS. It showed superior model discriminative ability and model-fitting performance over the other pathological classifications, and similar results were obtained in various patient settings. In addition, it showed superior net benefits over the Lauren classification and tumor differentiation grade in predicting 3- and 5-year OS. A novel prognostic nomogram incorporating the modified Lauren classification showed superior model discriminative ability, model-fitting performance, and net benefits over the American Joint Committee on Cancer 8^th edition tumor-node-metastasis classification.

CONCLUSION

The modified Lauren classification shows superior net benefits over the Lauren classification and tumor differentiation grade in predicting OS. A novel prognostic nomogram incorporating the modified Lauren classification shows good model discriminative ability, model-fitting performance, and net benefits.

Development and evaluation of a ceMDCT-based preoperative risk stratification model to predict disease-free survival after radical surgery in patients with gastric cancer

PURPOSE

To develop and evaluate a preoperative risk stratification model for predicting disease-free survival (DFS) based on contrast-enhanced multidetector computed tomography (ceMDCT) images in patients with gastric cancer (GC) undergoing radical surgery.

METHODS

We retrospectively enrolled patients with GC who underwent ceMDCT followed by radical surgery. A preoperative risk stratification model was constructed (including risk factor selection, risk status scoring, and risk level assignment) using Cox proportional hazard regression and log-rank analyses in the training cohort; the model was tested in the validation cohort. A nomogram was used to compare the preoperative risk stratification model with a postoperative DFS prediction model.

RESULTS

A total of 462 patients (training/validation: 271/191) were included. The ceMDCT features of T category (score of 0 or 2), N category (0, 1, 2, or 3), extramural vessel invasion (0 or 2), and tumor location (0 or 1) were selected to construct the preoperative risk stratification model, with 4 risk levels defined based on risk score. There were significant differences in DFS among the risk levels in both cohorts (p < 0.001). The predictive value of the preoperative model was similar to that of the postoperative model, with concordance indices of 0.791 (95% CI, 0.743-0.837) and 0.739 (95% CI, 0.666-0.812), respectively, in the training cohort and 0.762 (95% CI, 0.696-0.828) and 0.738 (95% CI, 0.684-0.792), respectively, in the validation cohort.

CONCLUSION

A preoperative risk stratification model based on ceMDCT images could be used to predict DFS and thus classify GC cases into various risk levels.

A Novel Deep Learning System for Diagnosing Early Esophageal Squamous Cell Carcinoma: A Multicenter Diagnostic Study

INTRODUCTION

This study aims to construct a real-time deep convolutional neural networks (DCNNs) system to diagnose early esophageal squamous cell carcinoma (ESCC) with white light imaging endoscopy.

METHODS

A total of 4,002 images from 1,078 patients were used to train and cross-validate the DCNN model for diagnosing early ESCC. The performance of the model was further tested with independent internal and external validation data sets containing 1,033 images from 243 patients. The performance of the model was then compared with endoscopists. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and Cohen kappa coefficient were measured to assess performance.

RESULTS

The DCNN model had excellent performance in diagnosing early ESCC with a sensitivity of 0.979, a specificity of 0.886, a positive predictive value of 0.777, a negative predictive value of 0.991, and an area under curve of 0.954 in the internal validation data set. The model also depicted a tremendously generalized performance in 2 external data sets and exhibited superior performance compared with endoscopists. The performance of the endoscopists was markedly elevated after referring to the predictions of the DCNN model. An open-accessed website of the DCNN system was established to facilitate associated research.

DISCUSSION

A real-time DCNN system, which was constructed to diagnose early ESCC, showed good performance in validation data sets. However, more prospective validation is needed to understand its true clinical significance in the real world.

Association of clinicopathological features and gastric cancer incidence in a single institution

BACKGROUND

Stomach cancer is the fifth most common malignancy. In 2012, 952,000 cancers were diagnosed worldwide, which led to 723,000 deaths. Elderly men are the most frequently observed category of gastric cancer patients, mostly affecting the antrum. The objective of this study was to analyze the association of age with sex, tumor sites, types of surgical intervention, and diagnosed anatomical pathologies in cases of gastric cancer.

METHODS

This cross-sectional descriptive study analyzed the associations between age, sex, tumor sites, types of surgical intervention, and diagnosed anatomical pathologies among the total gastric cancer incidences during medical treatments from January 2016 to May 2019. The study samples were collected from the total gastric cancer respondents who met the inclusion criteria during medical treatments within the study period.

RESULTS

Gastric cancer was most frequently observed among females (56%) and those aged 50-70 years old (47%). Most respondents had advanced stages of gastric cancer at first enrollment at our institution. The most frequently found tumor site was the corpus (43%). The most frequently performed type of surgical intervention was jejunostomy feeding (26%), and the most frequently diagnosed anatomical pathology was adenocarcinoma with poorly differentiation (39%). Overall, age had statistically significant correlations with sex (p < 0.001), tumor sites (p < 0.001), types of surgical intervention (p < 0.001), and diagnosed anatomical pathologies (p < 0.001).

CONCLUSION

Gastric cancer was more common in males than females. In the older age group (>50 years old), gastric cancer was more prevalent in women than men, and the gastric tumor tended to be more distal. Non-cardia gastric cancers were more prevalent than cardia gastric cancers.

Circular RNA hsa_circ_0001874 is an indicator for gastric cancer

BACKGROUND

Recent studies have indicated that circular RNAs (circRNAs) are novel endogenous RNAs whose 5' and 3' ends are covalently linked and play critical roles in gastric carcinogenesis. However, the significance of circRNA hsa_circ_0001874 in gastric cancer (GC) is still unclear.

METHODS

Therefore, we first detected hsa_circ_0001874 levels in GC cell lines and tissues and analyzed their potential correlation with clinicopathological factors. Then, a receiver operating characteristic (ROC) curve was established to evaluate its clinical value. Finally, we further predicted the biological functions of this molecule by bioinformatics analysis.

RESULTS

Our data showed that as an indicator, hsa_circ_0001874 expression was significantly decreased in 78.02% (71/91) of the GC patients. Combined with clinicopathological factors, the hsa_circ_0001874 level was strongly associated with cell differentiation (p < 0.001), tumor stage (p = 0.005), invasion (p = 0.024), lymphatic metastasis (p = 0.023), and CEA level (p < 0.001) in GC tissues. The area under the curve (AUC) was up to 0.673, with a sensitivity and specificity of 61.54% and 68.13%, respectively. Bioinformatics analysis showed that hsa_circ_0001874 harbors miR-593-5p, miR-103a-3p, and miR-107 seed sequences to regulate these three miRNAs and downstream target genes and exert its various biological functions in the carcinogenesis and progression of GC.

CONCLUSION

In summary, these data suggest that hsa_circ_0001874 is an indicator of GC and plays a significant role in gastric carcinogenesis and progression.

Short-term Outcomes of Gastric Cancer at University Teaching Hospital of Kigali (CHUK), Rwanda

PURPOSE

Gastric cancer is endemic in the so-called stomach cancer region comprising Rwanda, Burundi, South Western Uganda, and eastern Kivu province of Democratic Republic of Congo, but its outcomes in that region are under investigated. The purpose of this study was to describe the short-term outcomes (in-hospital mortality rate, length of hospital stay, 3-, 6-, 12-, and 24-month survival rates) in patients treated for gastric cancer in Rwanda.

METHODS

We retrospectively reviewed the data collected from records of patients who consulted Kigali University Teaching Hospital (CHUK) over a period of 10 years from September 2007 to August 2016. We followed patients before and after discharge for survival data. Baseline demographic data studied using descriptive statistics, whereas Kaplan-Meier model and univariate Cox regression were used for survival analysis.

RESULTS

Among 199 patients enrolled in this study, 92 (46%) were males and 107 (54%) females. The age was ranging between 24 and 93 years with a mean age of 55.4. The mean symptom duration was 15 months. Many patients had advanced disease, 62.3% with distant metastases on presentation. Treatment with curative intent was offered for only 19.9% of patients. The in-hospital mortality rate was 13.3%. The 3-, 6-, 12-, and 24-month survival rate was 52%, 40.5%, 28%, and 23.4%, respectively. The overall survival rate was 7 months.

CONCLUSION

Rwanda records a high number of delayed consultations and advanced disease at the time of presentation in patients with gastric cancer. This cancer is associated with poor outcomes as evidenced by high hospital mortality rates and short post discharge survival.

A deep learning-based system for identifying differentiation status and delineating the margins of early gastric cancer in magnifying narrow-band imaging endoscopy

BACKGROUND : Accurate identification of the differentiation status and margins for early gastric cancer (EGC) is critical for determining the surgical strategy and achieving curative resection in EGC patients. The aim of this study was to develop a real-time system to accurately identify differentiation status and delineate the margins of EGC on magnifying narrow-band imaging (ME-NBI) endoscopy. METHODS : 2217 images from 145 EGC patients and 1870 images from 139 EGC patients were retrospectively collected to train and test the first convolutional neural network (CNN1) to identify EGC differentiation status. The performance of CNN1 was then compared with that of experts using 882 images from 58 EGC patients. Finally, 928 images from 132 EGC patients and 742 images from 87 EGC patients were used to train and test CNN2 to delineate the EGC margins. RESULTS : The system correctly predicted the differentiation status of EGCs with an accuracy of 83.3 % (95 % confidence interval [CI] 81.5 % - 84.9 %) in the testing dataset. In the man - machine contest, CNN1 performed significantly better than the five experts (86.2 %, 95 %CI 75.1 % - 92.8 % vs. 69.7 %, 95 %CI 64.1 % - 74.7 %). For delineating EGC margins, the system achieved an accuracy of 82.7 % (95 %CI 78.6 % - 86.1 %) in differentiated EGC and 88.1 % (95 %CI 84.2 % - 91.1 %) in undifferentiated EGC under an overlap ratio of 0.80. In unprocessed EGC videos, the system achieved real-time diagnosis of EGC differentiation status and EGC margin delineation in ME-NBI endoscopy. CONCLUSION : We developed a deep learning-based system to accurately identify differentiation status and delineate the margins of EGC in ME-NBI endoscopy. This system achieved superior performance when compared with experts and was successfully tested in real EGC videos.

Major Histocompatibility Complex Class I-Related Chain A (MICA) Allelic Variants Associate With Susceptibility and Prognosis of Gastric Cancer

Gastric cancer (GC) is the fifth most prevalent type of cancer worldwide. Gastric tumor cells express MICA protein, a ligand to NKG2D receptor that triggers natural killer (NK) cells effector functions for early tumor elimination. MICA gene is highly polymorphic, thus originating alleles that encode protein variants with a controversial role in cancer. The main goal of this work was to study MICA gene polymorphisms and their relationship with the susceptibility and prognosis of GC. Fifty patients with GC and 50 healthy volunteers were included in this study. MICA alleles were identified using Sanger sequencing methods. The analysis of MICA gene sequence revealed 13 MICA sequences and 5 MICA-short tandem repeats (STR) alleles in the studied cohorts We identified MICA^*002 (^*A9) as the most frequent allele in both, patients and controls, followed by MICA^*008 allele (^*A5.1). MICA^*009/049 allele was significantly associated with increased risk of GC (OR: 5.11 [95% CI: 1.39–18.74], p = 0.014). The analysis of MICA-STR alleles revealed a higher frequency of MICA^*A5 in healthy individuals than GC patients (OR = 0.34 [95% CI: 0.12–0.98], p = 0.046). Survival analysis after gastrectomy showed that patients with MICA^*002/002 or MICA^*002/004 alleles had significantly higher survival rates than those patients bearing MICA^*002/008 (p = 0.014) or MICA^*002/009 (MICA^*002/049) alleles (p = 0.040). The presence of threonine in the position MICA-181 (MICA^*009/049 allele) was more frequent in GC patients than controls (p = 0.023). Molecular analysis of MICA-181 showed that the presence of threonine provides greater mobility to the protein than arginine in the same position (MICA^*004), which could explain, at least in part, some immune evasion mechanisms developed by the tumor. In conclusion, our findings suggest that the study of MICA alleles is crucial to search for new therapeutic approaches and may be useful for the evaluation of risk and prognosis of GC and personalized therapy.

Sexual Difference Matters: Females with High Microsatellite Instability Show Increased Survival after Neoadjuvant Chemotherapy in Gastric Cancer

Simple Summary

Here we report a sex- and age-specific analysis of 717 patients with gastric/gastro-esophageal adenocarcinomas treated with or without neoadjuvant chemotherapy (CTx) regarding overall survival (OS) and response to CTx. The analysis was also performed in molecular subtypes determined previously. Females demonstrated a significantly increased OS particularly in the group of patients treated with neoadjuvant CTx. Specifically in this patient group and taken into account the molecular subtypes, females with high microsatellite instability (MSI-H) showed the best survival followed by the male MSI-H, the female microsatellite stable (MSS) group and the male MSS group. Thus, we show an effect of sex on OS in gastric/gastro-esophageal cancer in particular for patients treated with neoadjuvant CTx. The superior survival of women with MSI-H tumors among the CTx patients implies that the combined consideration of these factors could contribute to an individualized treatment of the patients.

Abstract

We aimed to investigate patients with gastric/gastro-esophageal adenocarcinomas for sex- and age-specific differences regarding overall survival (OS) and response to neoadjuvant chemotherapy (CTx) under consideration of tumor specific molecular subtypes. Overall, 717 patients were analyzed, including 426 patients treated with and 291 treated without neoadjuvant CTx. Microsatellite instability (MSI) and Epstein-Barr virus positivity (EBV+) were determined previously. Females demonstrated a significantly increased OS (p = 0.035), particularly in the subgroup treated with CTx (p = 0.054). No significant differences regarding age were found. In the molecular subgroups, no sex-related differences were observed in the non-CTx group. However in the CTx group, females with MSI-high (H) tumors showed the best OS (p = 0.043), followed by the male MSI-H (p = 0.198) and female MSS (p = 0.114) compared to the male MSS group as reference. The interaction between sex and MSI in this patient group was noticeable (p = 0.053) and was included as a relevant factor in multivariable analyses. In conclusion, our results show an effect of sex on OS in gastric/gastro-esophageal cancer specifically for patients treated with neoadjuvant CTx. The superior survival of women with MSI-H tumors after neoadjuvant CTx implies that combined consideration of these factors could contribute to an individualized treatment of the patients.

Development and validation of a CT-based radiomics nomogram for preoperative prediction of tumor histologic grade in gastric adenocarcinoma

OBJECTIVES

To develop and validate a radiomics nomogram for preoperative prediction of tumor histologic grade in gastric adenocarcinoma (GA).

METHODS

This retrospective study enrolled 592 patients with clinicopathologically confirmed GA (low-grade: n=154; high-grade: n=438) from January 2008 to March 2018 who were divided into training (n=450) and validation (n=142) sets according to the time of computed tomography (CT) examination. Radiomic features were extracted from the portal venous phase CT images. The Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) regression model were used for feature selection, data dimension reduction and radiomics signature construction. Multivariable logistic regression analysis was applied to develop the prediction model. The radiomics signature and independent clinicopathologic risk factors were incorporated and presented as a radiomics nomogram. The performance of the nomogram was assessed with respect to its calibration and discrimination.

RESULTS

A radiomics signature containing 12 selected features was significantly associated with the histologic grade of GA (P<0.001 for both training and validation sets). A nomogram including the radiomics signature and tumor location as predictors was developed. The model showed both good calibration and good discrimination, in which C-index in the training set, 0.752 [95% confidence interval (95% CI): 0.701-0.803]; C-index in the validation set, 0.793 (95% CI: 0.711-0.874).

CONCLUSIONS

This study developed a radiomics nomogram that incorporates tumor location and radiomics signatures, which can be useful in facilitating preoperative individualized prediction of histologic grade of GA.

Discovering Biomarkers in Peritoneal Metastasis of Gastric Cancer by Metabolomics

Background and Objective

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

Methods

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

Results

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

Conclusion

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

Circular RNA expression profile and m6A modification analysis in poorly differentiated adenocarcinoma of the stomach

Aims: To profile and characterize the circular RNA (circRNA) expression pattern in poorly differentiated gastric adenocarcinoma (PDGA). Methods & materials: CircRNA expression profiles in PDGA and adjacent nontumor tissues were analyzed by microarray. Five randomly selected differentiated expressed circRNAs (DECs) were validated by real-time quantitative PCR. m6A qualification of the top 20 DECs was conducted by m6A-immunoprecipitation and real-time quantitative PCR. Results: A total of 65 DECs were found in PDGA compared with the control. Hsa_circRNA_0077837 had the largest area under the curve. Most DECs had m6A modifications, the trend of m6A modification alteration was mainly consistent with the circRNA expression level. Conclusion: Our study revealed a set of DECs and their m6A modification alterations, which may provide new insight for their potential function in PDGA.

A nomogram for prediction of stage III/IV gastric cancer outcome after surgery: A multicenter population-based study

Most patients with gastric cancer (GC) are first diagnosed at stage III‐IV and surgery resection remains the primary therapeutic modality for these patients. However, clinical staging used for prediction of those patients provides limited information. We collected clinicopathological data and disease‐progression information from 508 patients with stage III‐IV GC at three Chinese hospitals and 1298 patients from the Surveillance, Epidemiology, and End Results database. Based on the stepwise multivariate regression model, we constructed a novel nomogram to predict overall survival (OS). The performance of discrimination for this model was measured using Harrell's concordance index (C‐index) and receiver‐operating characteristic curve (ROC), and was validated using calibration plots. Multivariate Cox regression analyses showed that tumor size, age at diagnosis, N stage, tumor grade, and distant metastases were outstanding independent prognostic factors of stage III‐IV GC. We developed a nomogram based on these five prognostic predictors. In the training set, the C‐index of the nomogram was 0.645 (95% CI: 0.611‐0.679), which was higher than that of the American Joint Committee on Cancer TNM system alone (sixth TNM: 0.544; seventh TNM: 0.575; eighth TNM: 0.568). Similar results were observed in validation cohort. Moreover, calibration blots demonstrated good consistency between the actual and predicted OS probabilities. According to the nomogram, GC individuals could be classified into three groups (low‐, middle‐, and high‐risk) (P < .001). Our nomogram complements the current staging system for prediction of individual prognosis with stage III‐IV GC, and may be helpful for making individualized treatment decisions.

Diagnostic and prognostic values of anti-helicobacter pylori antibody combined with serum CA724, CA19-9, and CEA for young patients with early gastric cancer

Background

To investigate the value of anti‐helicobacter pylori (Hp) antibody, serum carbohydrate antigen (CA)‐724, CA19‐9, and carcinoembryonic antigen (CEA) in the diagnosis and prognosis evaluation of young patients with early gastric cancer.

Methods

A total of 200 young patients with gastric cancer from April 2014 to December 2015 were enrolled. A total of 206 patients with gastritis and 204 healthy subjects were also selected. Gastric cancer patients were followed up for 3 years, and the number of recurrences, metastasis, and death was recorded.

Results

The positive rate of anti‐Hp antibody, CA724, CA19‐9, and CEA in young patients with early gastric cancer were significantly higher than those in gastritis and healthy subjects (P < .05), and was positively correlated with tumor stage, tumor size, and lymph node metastasis (P < .05). The predicting model was as follows: Logit (P) = 26.433‐3.014(CA724)‐3.908(CA19‐9)‐0.303(CEA)‐2.208(anti‐Hp antibody, Positive = 1; Negative = 0). This model had a high value in identifying young patients with early gastric cancer with AUC of 0.918, and the estimated probability was .806. Compared to patients with negative anti‐Hp antibody and low serum levels of CA724, CA19‐9, and CEA, the recurrence rate, metastasis rate, and mortality of patients with positive anti‐Hp antibody, high serum levels of CA724, CA19‐9, and CEA increased significantly (P < .05).

Conclusion

This study indicated that anti‐Hp antibody combined with CA724, CA19‐9, and CEA had important value in the identification of young patients with early gastric cancer and were of great value in evaluating the risk of postoperative recurrence, metastasis, and death.

[Expression of PSMA 7 and its effect on proliferation, invasion, migration and tumorigenesis of gastric cancer]

OBJECTIVE

To study the expression of PSMA7 and its effect on proliferation, invasion and migration of gastric cancer and subcutaneous tumorigenesis in nude mice. >and subcutaneous tumorigenesis in nude mice.

METHODS

Specimens of tumor tissues and paired adjacent tissues were collected from 60 patients with gastric cancer for detecting the expression levels of PSMA7 using immunohistochemical method. Gastric cancer cell line SGC7901 was transfected with a lentiviral vector to inhibit PSMA7 expression, and the changes in cell proliferation and invasion were observed using cell counting kit-8 (CCK-8), clone formation assay and Transwell assay. A BALB/c mouse model bearing subcutaneous gastric cancer xenograft was established using SGC7901 cells with stable PSMA7 knockdown to assess the effect of low expression of PSMA7 on xenograft growth.

RESULTS

Gastric cancer tissues expressed significantly higher levels of PSMA7 than the paired adjacent tissues (P < 0.05). In SGC7901 cells, interference of PSMA7 expression significantly inhibited the cell proliferation and invasion (P < 0.05). In the tumor-bearing BALB/c mice, the xenografts derived from SGC7901 cells with PSMA7 expression interference showed significant growth suppression as compared with the control xenografts (P < 0.05).

CONCLUSIONS

PPSMA 7 is overexpressed in gastric cancer tissues, and PSMA7 knockdown inhibits the proliferation, invasion, migration and subcutaneous tumorigenesis of gastric cancer cells in nude mice.