Evaluation of the Eighth Edition of the American Joint Committee on Cancer TNM Staging System for Gastric Cancer: An Analysis of 7371 Patients in the SEER Database

Gastric Carcinoma in Autoimmune Gastritis: A Histopathologic and Molecular Study

Patients with autoimmune gastritis (AIG) have a 13-fold risk of developing type-1 neuroendocrine tumors, whereas the risk for gastric adenocarcinoma is still uncertain. Here we describe the clinicopathologic and molecular features of a series of gastric carcinomas (GC) arising in the context of AIG. A total of 26 AIG-associated GC specimens were collected from 4 Italian Institutions. Immunohistochemistry for MUC1, MUC2, MUC5AC, MUC6, CDX2, HER2, PD-L1, CLDN18, mismatch repair (MMR) proteins, and p53 and EBV-encoded RNA (EBER) in situ hybridization were performed. Histologic and immunohistochemical features were jointly reviewed by 5 expert gastrointestinal pathologists. Next-generation sequencing analysis (TrueSight Oncology 500, Illumina) of 523 cancer-related genes was performed on 19 cases. Most tumors were diagnosed as pT1 (52%) and they were located in the corpus/fundus (58%) and associated with operative link for gastritis assessment stage II gastritis (80.8%), absence of parietal cells, complete intestinal metaplasia, and enterochromaffin-like-cell micronodular hyperplasia. Only 4 (15.4%) GCs were diagnosed during follow-up for AIG. The following histotypes were identified: 20 (77%) adenocarcinomas; 3 (11%) mixed neuroendocrine-non-neuroendocrine neoplasms, and 2 (8%) high-grade solid adenocarcinomas with focal neuroendocrine component, 1 (4%) adenocarcinoma with an amphicrine component. Overall, 7 cases (27%) showed MMR deficiency, 3 (12%) were positive (score 3+) for HER2, 6 (23%) were CLDN18 positive, and 11 (42%) had PD-L1 combined positive score ≥ 10. EBER was negative in all cases. Molecular analysis revealed 5/19 (26%) microsatellite instability (MSI) cases and 7 (37%) tumor mutational burden (TMB) high. The most frequently altered genes were TP53 (8/19, 42%), RNF43 (7/19, 37%), ERBB2 (7/19, 37% [2 amplified and 5 mutated cases]), ARID1A (6/19, 32%), and PIK3CA (4/19, 21%). In summary, AIG-associated GCs are often diagnosed at low stage in patients with longstanding misrecognized severe AIG; they often display a neuroendocrine component or differentiation, have relatively higher rates of MMR deficiency, and TMB high.

Development and validation of prognostic nomogram for patients with metastatic gastric adenocarcinoma based on the SEER database

The aim of this study was to investigate the prognostic factors affecting overall survival in patients with metastatic gastric adenocarcinoma and to establish a nomogram prediction model for comprehensive clinical application. Data from 2370 patients with metastatic gastric adenocarcinoma between 2010 and 2017 were retrieved from the surveillance, epidemiology, and end results database. They were randomly divided into a training set (70%) and a validation set (30%), univariate and multivariate Cox proportional hazards regressions were used to screen important variables that may affect overall survival and to establish the nomogram. The nomogram model was evaluated using a receiver operating characteristic curve, calibration plot, and decision curve analysis. Internal validation was performed to test the accuracy and validity of the nomogram. Univariate and multivariate Cox regression analyses revealed that, age, primary site, grade, and American joint committee on cancer. T, bone metastasis, liver metastasis, lung metastasis, tumor Size, and chemotherapy were identified as independent prognostic factors for overall survival and were included in the prognostic model to construct a nomogram. The prognostic nomogram showed good overall survival risk stratification ability for the area under the curve, calibration plots, and decision curve analysis in both the training and validation sets. Kaplan-Meier curves further showed that patients in the low-risk group had better overall survival. This study synthesizes the clinical, pathological, therapeutic characteristics of patients with metastatic gastric adenocarcinoma, establishes a clinically effective prognostic model, and that can help clinicians to better evaluate the patient's condition and provide accurate treatment.

A 9‑gene expression signature to predict stage development in resectable stomach adenocarcinoma

BACKGROUND

Stomach adenocarcinoma (STAD) is a highly heterogeneous disease and is among the leading causes of cancer-related death worldwide. At present, TNM stage remains the most effective prognostic factor for STAD. Exploring the changes in gene expression levels associated with TNM stage development may help oncologists to better understand the commonalities in the progression of STAD and may provide a new way of identifying early-stage STAD so that optimal treatment approaches can be provided.

METHODS

The RNA profile retrieving strategy was utilized and RNA expression profiling was performed using two large STAD microarray databases (GSE62254, n = 300; GSE15459, n = 192) from the Gene Expression Omnibus (GEO) and the RNA-seq database within the Cancer Genome Atlas (TCGA, n = 375). All sample expression information was obtained from STAD tissues after radical resection. After excluding data with insufficient staging information and lymph node number, samples were grouped into earlier-stage and later-stage. Samples in GSE62254 were randomly divided into a training group (n = 172) and a validation group (n = 86). Differentially expressed genes (DEGs) were selected based on the expression of mRNAs in the training group and the TCGA group (n = 156), and hub genes were further screened by least absolute shrinkage and selection operator (LASSO) logistic regression. Receiver operating characteristic (ROC) curves were used to evaluate the performance of the hub genes in distinguishing STAD stage in the validation group and the GSE15459 dataset. Univariate and multivariate Cox regressions were performed sequentially.

RESULTS

22 DEGs were commonly upregulated (n = 19) or downregulated (n = 3) in the training and TCGA datasets. Nine genes, including MYOCD, GHRL, SCRG1, TYRP1, LYPD6B, THBS4, TNFRSF17, SERPINB2, and NEBL were identified as hub genes by LASSO-logistic regression. The model achieved discrimination in the validation group (AUC = 0.704), training-validation group (AUC = 0.743), and GSE15459 dataset (AUC = 0.658), respectively. Gene Set Enrichment Analysis (GSEA) was used to identify the potential stage-development pathways, including the PI3K-Akt and Calcium signaling pathways. Univariate Cox regression indicated that the nine-gene score was a significant risk factor for overall survival (HR = 1.28, 95% CI 1.08-1.50, P = 0.003). In the multivariate Cox regression, only SCRG1 was an independent prognostic predictor of overall survival after backward stepwise elimination (HR = 1.21, 95% CI 1.11-1.32, P < 0.001).

CONCLUSION

Through a series of bioinformatics and validation processes, a nine-gene signature that can distinguish STAD stage was identified. This gene signature has potential clinical application and may provide a novel approach to understanding the progression of STAD.

Optimizing the Choice for Adjuvant Chemotherapy in Gastric Cancer

Simple Summary

Gastric cancer is the fourth largest cause of tumor-related death worldwide. Despite advances in the management of resectable cancer and improvements in early diagnosis, especially in east Asia where screening campaigns are actively performed, many patients experience recurrence and die because of the disease. Adjuvant systemic chemotherapy is administered after radical surgery in order to reduce the risk of recurrence and death. The modality of administration and regimens of chemotherapy in this setting are different between Eastern and Western countries. In Asia, adjuvant chemotherapy is traditionally given after surgery, while in Europe it is commonly scheduled after preoperative chemotherapy and surgery (perioperative chemotherapy), and in Northern America it is usually combined with radiotherapy (chemoradiotherapy). All these approaches are sustained by well-designed phase III clinical studies, and none may be considered superior to the others in the absence of head-to-head comparisons. The identification of predictive and/or prognostic factors could help to select patients at higher risk of recurrence and those more likely to receive a benefit from the adjuvant treatment. This would allow clinicians to avoid the administration of undue toxicity to non-responder patients and even to reduce the cost of unnecessary treatment.

Abstract

Advances in the management of gastric cancer have improved patient survival in the last decade. Nonetheless, the number of patients relapsing and dying after a diagnosis of localized gastric cancer is still too high, even in early stages (10% in stage I). Adjuvant systemic chemotherapy has been proven to significantly improve outcomes. In the present article we have critically reviewed the clinical trials that guide the current clinical practice in the adjuvant treatment of patients affected by resectable gastric cancer, focusing on the different approaches worldwide, i.e., adjuvant chemotherapy, adjuvant chemoradiotherapy, and perioperative chemotherapy. We also delineate the clinical–pathological characteristics that are commonly taken into account to identify patients at a higher risk of recurrence and requiring adjuvant chemotherapy, and also describe novel biomarkers and therapeutic agents that might allow personalization of the treatment.

A predictive model for early death in elderly patients with gastric cancer: A population-based study

Background

The mean age of gastric cancer (GC) patients has increased due to the aging society. Elderly GC patients with poor physical status tend to develop complications during the treatment courses, which cause early death. This study aimed to identify risk factors and establish nomograms for predicting total early death and cancer-specific early death in elderly GC patients.

Methods

Data for elderly GC patients were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. These patients were randomly assigned to a training cohort and a validation cohort. The univariate logistic regression model and backward stepwise logistic regression model were used to identify independent risk factors for early death. Nomograms were constructed to predict the overall risk of early death and their performance was validated by receiver operating characteristic (ROC) curve, calibration curve, decision curve analyses (DCA), integrated discrimination improvement (IDI), and net reclassification improvement (NRI) in both training and validation cohorts.

Results

Among the 3102 enrolled patients, 1114 patients died within three months from the first diagnosis and 956 of them died due to cancer-specific causes. Non-Asian or Pacific Islander (API) race, non-cardia/fundus or lesser/greater curvature, higher AJCC stage, no surgery and no chemotherapy were all related to a high risk of both all-cause early death and cancer-specific early death. Higher T stage and N0 stage were only positively related to total early mortality, while liver metastasis was only positively related to cancer-specific early mortality. Based on these identified factors, two nomograms were developed for predicting the risk of all-cause and cancer-specific early death, which showed good performance with the AUC of the nomograms were 0.775 and 0.766, respectively. The calibration curves, DCAs, NRI, and IDI also confirmed the value of these nomograms.

Conclusions

These nomogram models were considered a practical tool to identify the early death of elderly GC patients and help provide a more individualized treatment strategy.

Revisiting the 8th AJCC system for gastric cancer: A review on validations, nomograms, lymph nodes impact, and proposed modifications

Gastric cancer is the fifth most frequently diagnosed cancer worldwide, behind breast, lung, colorectal, and prostate cancers. In gastric cancer, multimodality treatment shows prospective benefits and also improves survival. Surgery, however, is the mainstay of curative treatment. The staging of gastric cancer patients is critical for harmonization of care. Accurate stages assure that informed clinical decisions are timely made. The American Joint Committee on Cancer (AJCC) staging system is the most widely applied system in to determine the disease's prognosis and survival prediction. The recently adopted 8th AJCC TNM staging system has been revised to enhance its survival predictive power. Subsequent studies have established the validity of the current edition, demonstrating improved stage stratification, discriminatory power, and survival prediction. However, other studies have cast doubt on the superiority of the new edition. Innovations aimed at further improving its prognosis have resulted in developing of novel models. Advances in our understanding of the tumor microenvironment and molecular categorization of cancer have resulted in proposals for their inclusion in TNM staging as potential complementary factors that enhance survival prediction and prognostic assessment ability. The purpose of this study is to conduct a review of the published literature regarding the validity of the 8th AJCC TNM staging system, proposed modifications, and nomograms.

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The 8th AJCC is valid in prognostic stratification of gastric cancer, however, revisions are still required.

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The yPT staging requires some modifications and inclusion of stages that currently don't exist in the 8th AJCC.

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High lymph nodes count and anatomical localization improve the prediction ability of the current AJCC.

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Nomograms comprising of individual prognostic factors are crucial to the current AJCC.

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Molecular markers positively influence survival prediction of gastric cancer.

Accurate diagnosis and prognosis prediction of gastric cancer using deep learning on digital pathological images: A retrospective multicentre study

BACKGROUND

To reduce the high incidence and mortality of gastric cancer (GC), we aimed to develop deep learning-based models to assist in predicting the diagnosis and overall survival (OS) of GC patients using pathological images.

METHODS

2333 hematoxylin and eosin-stained pathological pictures of 1037 GC patients were collected from two cohorts to develop our algorithms, Renmin Hospital of Wuhan University (RHWU) and the Cancer Genome Atlas (TCGA). Additionally, we gained 175 digital pictures of 91 GC patients from National Human Genetic Resources Sharing Service Platform (NHGRP), served as the independent external validation set. Two models were developed using artificial intelligence (AI), one named GastroMIL for diagnosing GC, and the other named MIL-GC for predicting outcome of GC.

FINDINGS

The discriminatory power of GastroMIL achieved accuracy 0.920 in the external validation set, superior to that of the junior pathologist and comparable to that of expert pathologists. In the prognostic model, C-indices for survival prediction of internal and external validation sets were 0.671 and 0.657, respectively. Moreover, the risk score output by MIL-GC in the external validation set was proved to be a strong predictor of OS both in the univariate (HR = 2.414, P < 0.0001) and multivariable (HR = 1.803, P = 0.043) analyses. The predicting process is available at an online website (https://baigao.github.io/Pathologic-Prognostic-Analysis/).

INTERPRETATION

Our study developed AI models and contributed to predicting precise diagnosis and prognosis of GC patients, which will offer assistance to choose appropriate treatment to improve the survival status of GC patients.

FUNDING

Not applicable.

Comparison of a Tumor-Ratio-Metastasis Staging System and the 8th AJCC TNM Staging System for Gastric Cancer

Background

Despite the implementation of the 8th American Joint Committee on Cancer (AJCC) TNM staging system for gastric cancer (GC) in 2017, it still holds a significant level of stage migration which affects patients’ proper classification and accurate prognosis. Here, to reduce this effect, we evaluated the prognostic value of a lymph node ratio (LNR) and established a novel tumor–ratio–metastasis (TRM) staging system.

Method

The data of 15,206 GC patients from the Sun Yat-sen University Cancer Center (Training set; n=2,032) and the US Surveillance, Epidemiology, and End Results (SEER) database (Validation set; n=13,174) were analyzed. The training set was classified into 5 LNR categories, based on which the novel TRM staging system was constructed. The overall survival (OS) between the TRM and AJCC TNM systems was compared in the training set and validated in the validation set. The likelihood ratio x², liner trend x², C-index, and Akaike information criterion (AIC) values were used to measure the discriminatory ability between the two different staging systems. Decision curve analyses (DCAs) were conducted to test the clinical value of the two staging systems.

Result

The patients were classified into the following categories: LNR0: 0%, LNR1: 0%<LNR ≤ 10%, LNR2: 10%<LNR ≤ 25%, LNR 3a: 25%<LNR ≤ 60%, and LNR 3b: LNR>60%. Univariate analyses demonstrated that the log-rank x² of the LNR stage (Training/Validation set: x² = 463.1/2880.8) was larger than the AJCC pN stage (Training/Validation set: x² = 281.5/2240.8). For both the training set and validation set, stratified analyses using the Kaplan-Meier method identified significantly heterogeneous OS in every pN category but only one using the LNR. The TRM staging system had higher likelihood ratio x², liner trend x², C-index and smaller AIC values than the TNM system.

Conclusion

The TRM staging system demonstrated improved homogeneity and discriminatory ability in predicting the prognosis of GC patients compared with the AJCC TNM staging system.

Impact of the extent of negative lymph nodes in gastric adenocarcinoma undergoing primary surgical resection: An institutional report

BACKGROUND

Sub-total/total gastrectomy with lymph node dissection (LND) remains an effective therapeutic strategy for resectable gastric adenocarcinomas (GACs). Despite the prognostic significance of positive lymph nodes (PLNs) defined in N-status, few have appraised the impacts of negative lymph nodes (NLNs) and the percentage of NLN (=number of NLNs/number of total lymph nodes [TLNs], %), as well as the extent of TLNs to be dissected in GACs.

METHODS

We retrospectively analyzed 62 GAC patients (mean age of 67.1 years; 41 men) undergoing primary sub-total/total gastrectomy from a single institute. Candidate variables, including the number of NLNs (≤9 and >9) and the percentage of NLN (≤37.5, 37.5-80.6 and >80.6, %), were evaluated to determine their prognostic impacts and hazard ratios (HRs).

RESULTS

Under the multivariate Cox proportional-hazards regression model, tumor length exceeding 4 cm (p = 0.017; HR = 2.828), perineural invasion (p = 0.037; HR = 3.182), and lower percentage of NLN (p = 0.016 and p = 0.060; HRs = 1.000, 0.327, and 0.333 for subgroups ≤37.5, 37.5-80.6, and >80.6, respectively) were three independent predictors with elevated HRs for poor prognosis. GAC patients with the percentage of NLN > 80.6 were highly related to those with NLNs > 9 (p < 0.001), and GAC patients with NLNs > 9 were highly related to those with TLNs > 15 (p < 0.001). For all 62 GAC or 42 N(+) GAC patients, those who underwent LND with TLNs>15 tended to have more PLNs (p = 0.018, p = 0.003) and more NLNs (p < 0.001, p = 0.029) than did those with TLNs ≤ 15. Among the 42 GAC patients with TLNs > 15, a lower percentage of NLN (p = 0.026 and p = 0.015; HRs = 1.000, 0.272, and 0.180 for subgroups ≤37.5, 37.5-80.6, and >80.6, respectively) remained an independent predictor of poor prognosis.

CONCLUSION

The percentage of NLN could predict the prognosis of GAC patients properly. However, an accurate percentage of NLN needs a minimal requirement of TLNs > 15 to detect an adequate number of PLNs and sufficient number of NLNs.

Predicting gastric cancer outcome from resected lymph node histopathology images using deep learning

N-staging is a determining factor for prognostic assessment and decision-making for stage-based cancer therapeutic strategies. Visual inspection of whole-slides of intact lymph nodes is currently the main method used by pathologists to calculate the number of metastatic lymph nodes (MLNs). Moreover, even at the same N stage, the outcome of patients varies dramatically. Here, we propose a deep-learning framework for analyzing lymph node whole-slide images (WSIs) to identify lymph nodes and tumor regions, and then to uncover tumor-area-to-MLN-area ratio (T/MLN). After training, our model’s tumor detection performance was comparable to that of experienced pathologists and achieved similar performance on two independent gastric cancer validation cohorts. Further, we demonstrate that T/MLN is an interpretable independent prognostic factor. These findings indicate that deep-learning models could assist not only pathologists in detecting lymph nodes with metastases but also oncologists in exploring new prognostic factors, especially those that are difficult to calculate manually.

The ratio of tumour area to metastatic lymph node area (T/MLN) is a clinical indicator that can improve prognosis prediction of gastric cancer. Here, the authors use machine learning on whole slide images to generate a method that can predict metastatic lymph nodes and obtain T/MLN.

The Clinical Significance of Lymphovascular Invasion in Gastric Cancer

BACKGROUND/AIM

Lymphovascular invasion (LVI) is recognized as a prognostic predictor of recurrence in certain carcinomas. According to current Japanese guidelines, however, in gastric cancer, LVI is not clinically useful information, except for predicting the curability of endoscopic resection. We clarified the clinical significance of LVI in gastric cancer and its correlation with disease prognosis.

PATIENTS AND METHODS

A total of 2,090 cases of gastric cancer undergoing radical gastrectomy were enrolled. The correlation of LVI and other histopathological factors was evaluated with regards to patient prognosis.

RESULTS

LVI(+) was noted in 894 cases. A multivariate analysis showed that pT, pN, and LVI were independent risk factors for patient prognosis. In pT2-4 patients with nodal metastasis, a significant difference was revealed, and the 5-year overall survival rates in LVI(+) cases were lower than those in LVI(-) (60.9% vs. 76.7%, p=0.005).

CONCLUSION

LVI in gastric cancer is an independent prognostic factor, and tends to worsen prognosis, especially in advanced cancers with lymph node metastases.

A Predictive Nomogram for Early Mortality in Stage IV Gastric Cancer

Background

The study was intended to establish predictive nomogram models for predicting total early mortality (the probability of surviving less than or equal to 3 months) and cancer-specific early mortality in patients with stage IV gastric cancer. This was the first study to establish prognostic survival in patients with stage IV gastric cancer.

Material/Methods

Patients from the SEER database were identified using inclusion and exclusion criteria. Their clinical characteristics were statistically analyzed. The Kaplan-Meier method and the log-rank test were used to compare the influences of different factors on survival time. Logistic regression models were conducted to explore the correlative factors of early mortality. A nomogram was established based on factors significant in the logistic regression model and an internal validation was performed.

Results

Of the 11,036 eligible patients included in the study, 4932 (44.7%) patients resulted in total early death (42.6% died of the cancer and 2.1% died of other reasons). Larger tumor size, poor differentiation, and liver metastasis were positively related to cancer-specific early mortality. Surgery was negatively related to total early mortality and cancer-specific early mortality, while cardia was only negatively associated with total early death. Predictive nomogram models for total early mortality and cancer-specific early mortality have been validated internally. The areas under the receiver operating characteristics curve were 73.5%, and 68.0%, respectively, and the decision curve analysis also proved the value of the models.

Conclusions

The nomogram models proved to be a suitable tool for predicting the early mortality in stage IV gastric cancer.

Gastric Carcinoma in Young Patients and Its Clinicopathological Characteristics and Prognosis

Background

Gastric cancer is usually an age-related disease and mostly diagnosed after the sixth decade of life, though it may also be diagnosed earlier.

Objective

The aim of this study is to explore the clinicopathological characteristics and prognosis of gastric carcinoma in young patients.

Methods

A total of 1379 patients younger than 75 years histologically diagnosed with primary gastric carcinoma underwent gastrectomy. Patients were categorized into three groups based on their age which included young age group (≤40 years), middle-aged group (age 41-60 years), and elderly group (age 61-75 years). The young age group was further subdivided into two groups: Group A (age ≤35 years) and Group B (age 35-40 years). The analysis of the clinicopathological characteristics and prognosis followed thereafter.

Results

Females predominate in young group (p < 0.001). A significantly higher undifferentiated histological pattern was found in the young age group from the other two groups (p < 0.001). Tumor location in the lower third of the stomach was significantly higher in the young group than the other groups (p < 0.001). T4 stage was common in young patients similar to the middle and old age group (p = 0.049). Distal gastrectomy was performed more in the young age group rather than the middle and old age groups with the following percentage ratios: young group 74.5% (123/165), middle age group 59.9% (429/716), and old age group 52.2% (260/498) (p < 0.001). The 5-year overall survival rate of the young, middle, and old age groups were 46%, 48%, and 39%, respectively, whereas the 5-year overall survival rates of the subgroups of young patients, Group A and Group B, were 33% and 49%, respectively. Multivariate analysis revealed that independent negative prognostic factors were as follows: tumor location (L), p = 0.016, OR = 0.795, 95%CI = [0.659; 0.959]; larger tumor size, p = 0.026, OR = 1.727, 95%CI = [1.067; 2.797]; resection margin, p < 0.001, OR = 2.167, 95%CI = [1.751; 2.682]; tumor stage (T4), p < 0.001, OR = 2.572, 95%CI = [1.709; 3.870]; and nodal involvement N1, p = 0.005, OR = 1.506, 95%CI = [1.123; 2.020]; N2, p < 0.001, OR = 1.708, 95%CI = [1.289; 2.263]; and N3, p < 0.001, OR = 2.986, 95%CI = [2.314; 3.854].

Conclusion

The young age groups of patients were predominantly female and had a higher proportion of poorly differentiated and undifferentiated type of tumor; moreover, patients aged <35 years had a poor prognosis. In addition, gastric cancer can occur in patients less than 30 years old, and symptoms suggestive of gastric cancer should be investigated aggressively; therefore, a close scrutiny and monitoring should be done in younger patients especially those associated with high-risk factors which could indicate the presence of the disease at an early stage.

Gastric Carcinoma in Young Patients and Its Clinicopathological Characteristics and Prognosis

Background. Gastric cancer is usually an age-related disease and mostly diagnosed after the sixth decade of life, though it may also be diagnosed earlier. Objective. The aim of this study is to explore the clinicopathological characteristics and prognosis of gastric carcinoma in young patients. Methods. A total of 1379 patients younger than 75 years histologically diagnosed with primary gastric carcinoma underwent gastrectomy. Patients were categorized into three groups based on their age which included young age group (≤40 years), middle-aged group (age 41-60 years), and elderly group (age 61-75 years). The young age group was further subdivided into two groups: Group A (age ≤35 years) and Group B (age 35-40 years). The analysis of the clinicopathological characteristics and prognosis followed thereafter. Results. Females predominate in young group (p<0.001). A significantly higher undifferentiated histological pattern was found in the young age group from the other two groups (p<0.001). Tumor location in the lower third of the stomach was significantly higher in the young group than the other groups (p<0.001). T4 stage was common in young patients similar to the middle and old age group (p=0.049). Distal gastrectomy was performed more in the young age group rather than the middle and old age groups with the following percentage ratios: young group 74.5% (123/165), middle age group 59.9% (429/716), and old age group 52.2% (260/498) (p<0.001). The 5-year overall survival rate of the young, middle, and old age groups were 46%, 48%, and 39%, respectively, whereas the 5-year overall survival rates of the subgroups of young patients, Group A and Group B, were 33% and 49%, respectively. Multivariate analysis revealed that independent negative prognostic factors were as follows: tumor location (L), p=0.016, OR=0.795, 95%CI=0.659;0.959; larger tumor size, p=0.026, OR=1.727, 95%CI=1.067;2.797; resection margin, p<0.001, OR=2.167, 95%CI=1.751;2.682; tumor stage (T4), p<0.001, OR=2.572, 95%CI=1.709;3.870; and nodal involvement N1, p=0.005, OR=1.506, 95%CI=1.123;2.020; N2, p<0.001, OR=1.708, 95%CI=1.289;2.263; and N3, p<0.001, OR=2.986, 95%CI=2.314;3.854. Conclusion. The young age groups of patients were predominantly female and had a higher proportion of poorly differentiated and undifferentiated type of tumor; moreover, patients aged <35 years had a poor prognosis. In addition, gastric cancer can occur in patients less than 30 years old, and symptoms suggestive of gastric cancer should be investigated aggressively; therefore, a close scrutiny and monitoring should be done in younger patients especially those associated with high-risk factors which could indicate the presence of the disease at an early stage.

Gastric Carcinoma in Young Patients and Its Clinicopathological Characteristics and Prognosis

Background. Gastric cancer is usually an age-related disease and mostly diagnosed after the sixth decade of life, though it may also be diagnosed earlier. Objective. The aim of this study is to explore the clinicopathological characteristics and prognosis of gastric carcinoma in young patients. Methods. A total of 1379 patients younger than 75 years histologically diagnosed with primary gastric carcinoma underwent gastrectomy. Patients were categorized into three groups based on their age which included young age group (≤40 years), middle-aged group (age 41-60 years), and elderly group (age 61-75 years). The young age group was further subdivided into two groups: Group A (age ≤35 years) and Group B (age 35-40 years). The analysis of the clinicopathological characteristics and prognosis followed thereafter. Results. Females predominate in young group (p<0.001). A significantly higher undifferentiated histological pattern was found in the young age group from the other two groups (p<0.001). Tumor location in the lower third of the stomach was significantly higher in the young group than the other groups (p<0.001). T4 stage was common in young patients similar to the middle and old age group (p=0.049). Distal gastrectomy was performed more in the young age group rather than the middle and old age groups with the following percentage ratios: young group 74.5% (123/165), middle age group 59.9% (429/716), and old age group 52.2% (260/498) (p<0.001). The 5-year overall survival rate of the young, middle, and old age groups were 46%, 48%, and 39%, respectively, whereas the 5-year overall survival rates of the subgroups of young patients, Group A and Group B, were 33% and 49%, respectively. Multivariate analysis revealed that independent negative prognostic factors were as follows: tumor location (L), p=0.016, OR=0.795, 95%CI=0.659;0.959; larger tumor size, p=0.026, OR=1.727, 95%CI=1.067;2.797; resection margin, p<0.001, OR=2.167, 95%CI=1.751;2.682; tumor stage (T4), p<0.001, OR=2.572, 95%CI=1.709;3.870; and nodal involvement N1, p=0.005, OR=1.506, 95%CI=1.123;2.020; N2, p<0.001, OR=1.708, 95%CI=1.289;2.263; and N3, p<0.001, OR=2.986, 95%CI=2.314;3.854. Conclusion. The young age groups of patients were predominantly female and had a higher proportion of poorly differentiated and undifferentiated type of tumor; moreover, patients aged <35 years had a poor prognosis. In addition, gastric cancer can occur in patients less than 30 years old, and symptoms suggestive of gastric cancer should be investigated aggressively; therefore, a close scrutiny and monitoring should be done in younger patients especially those associated with high-risk factors which could indicate the presence of the disease at an early stage.

Topographic lymph node staging system shows prognostic superiority compared to the 8th edition of AJCC TNM in gastric cancer. A western monocentric experience

INTRODUCTION

The current Tumor Node Metastasis staging system (TNM) for gastric cancer classifies the extent of lymph node metastasis based upon the number of lymph nodes involved. Choi et al. have recently proposed a new anatomical classification based upon the regionality of the involved nodes. This new classification seems to have a better predictive prognostic value than the traditional one. We investigated the prognostic role of the new anatomical based classification, reviewing our institutional gastric cancer database.

METHODS

We performed a retrospective chart review of 329 patients who underwent gastrectomy at our Institution from 2003 to 2017. We excluded from data analysis any patient with distant metastases at the time of first diagnosis and or surgery, pathology other than adenocarcinoma, lymphadenectomy less than D2, impossibility to identify location of lymph nodes (LNs) on pathological report and neoadjuvant chemotherapy. The extent of D2 lymphadenectomy was defined according to Japanese Gastric Cancer Association criteria. LN metastasis were reclassified into three topographic groups (lesser, greater curvature, and extraperigastric nodes) and staged according to Choi. The new N stage was combined with the current pT according to the 8th edition of TNM and a new hybrid TNM stage was established. All patients were followed up until June 2019. The prognostic performance of the new stage and of the current anatomical numeric based system (TNM) was analyzed and assessed by the C-index, AIC and likelihood ratio χ² value.

RESULTS

In predicting both Overall Survival (OS) and Disease free Survival (DFS) the new N stage and the new TNM staging system had the highest C-index and likelihood ratio χ2 value and the lowest Akaike Information Criterion (AIC), showing a better accuracy and displaying a better prognostic performance.

CONCLUSIONS

Our study is the first from the Western world to compare the new hybrid classification, based on the anatomical location of metastatic nodes, to the 8th of American Joint Committee on Cancer (AJCC) TNM staging system. Our findings on a small, monocentric sample suggest that hybrid topographic lymph node staging system is more accurate than TNM.

Reduced expression of circRNA hsa_circ_0067582 in human gastric cancer and its potential diagnostic values

BACKGROUND

Gastric cancer (GC) is one of the global mortality diseases and has a poor prognosis due to the lack of ideal tumor biomarkers. Circular RNAs (circRNAs) are an abundant kind of endogenous RNAs that recently are found play a crucial role in the cancer occurrence and development. Nevertheless, little is known with regard to the diagnostic values of these circRNAs for GC. In this article of research, we investigated the role of hsa_circ_0067582 in clinical diagnosis of GC.

MATERIALS AND METHODS

We used divergent primers, and the expression levels of hsa_circ_0067582 in 93 fresh GC tissues and paired adjacent normal tissues from surgical patients were detected using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Then, a receiver operating characteristic (ROC) curve was established to assess the diagnostic significance of hsa_circ_0067582. The relationship between expression of hsa_circ_0067582 and clinicopathological factors of patients was made further explored.

RESULTS

Hsa_circ_0067582 levels were significantly decreased in GC tissues contrasted with adjacent normal tissues (n = 93, P < .001). After that, we discovered that it was evidently downregulated in 81.7% (76/93) GC tissues. The area under the ROC curve (AUC) of hsa_circ_0067582 was up to 0.6937, the sensitivity was 66.67%, and the specificity was 61.29%. Moreover, the hsa_circ_0067582 levels were obviously associated with tumor diameter (P = .002) and carbohydrate antigen 19-9 (CA19-9, P = .01). Meanwhile, after operation, low-level group of hsa_circ_0067582 of GC patients was associated with better prognosis.

CONCLUSION

Our data imply that hsa_circ_000067582 may be a potential biomarker for GC diagnosis and prognosis evaluation.

Proposal of a New TNM Classification for Gastric Cancer: Focusing on pN3b and Cytology-Positive (CY1) Disease

Purpose

Gastric cancer with lymph node metastasis (LNM) more than 15 (N3b) was defined as stage IV until the 6th AJCC system. However, it has been reclassified as a localized disease (stage IIb or III) since the 7th system. The aim of this study is to demonstrate that the survival of N3b is comparable to cytology-only positive (CY1-only) stage IV and to propose a new TNM system interpreting N3b as an eligibility criterion for receiving more intensive chemotherapy regimens.

Materials and Methods

1,430 patients who underwent gastric cancer surgery at Seoul National University Hospital from 2007 to 2012 were retrospectively analyzed. The 5-year survival rate (5YSR) and 3-year recurrence-free survival (RFS) were evaluated according to the 7th and 8th systems, as well as a new categorization based on N-classification; N0-2 (LNM<7), N3a (LNM 7–15), or N3b (LNM>15).

Results

The survival of N3b is comparable to that of CY1-only stage IV (log rank test, P=0.671) and is distinct from that of grossly stage IV (log rank test, P<0.001). The survival of the remaining stage IIIc (T4bN3a) was comparable to those of N3b and CY1-only stage IV. Most N3b patients had significantly shorter 3-year RFS and mean RFS than those with IIb–IIIc, as if N3b itself was a higher TNM stage.

Conclusions

In terms of survival, T4bN3a, N3b, and CY1-only stage IV were unified as stage IVa, while grossly stage IV was defined as stage IVb. N3b can be regarded as an eligibility criterion for undergoing more intensive chemotherapy regimens.