The IGCA staging system is more accurate than AJCC7 system in stratifying survival of patients with gastric cancer in stage III

The combination of preoperative fibrinogen-to-albumin ratio and postoperative TNM stage (FAR-TNM) predicts the survival in gastric cancer patients after gastrectomy

OBJECTIVE

There are many factors that affect the survival of patients with gastric cancer, such as TNM stage, the patient's nutritional status, inflammation, and so on. In this study, the prognostic significance of preoperative fibrinogen-to-albumin ratio (FAR) and postoperative TNM staging in patients with gastric cancer was retrospectively studied.

METHODS

A total of 265 patients (surgery dates from January 2007 to December 2013) were included in this retrospective study. All the patients were confirmed by pathology after operation. Categorical variables were compared using the χ2 test. Kaplan-Meier and log-rank tests were used for survival analysis. Cox proportional hazard models were used to assess prognostic factors. Nomogram was applied to predict the prognosis of overall survival (OS).

RESULTS

The higher the FAR value, the more lymph node metastasis, the later the TNM stage, and the shorter the survival time. We established a new scoring system, the FAR-TNM score, which combined FAR and TNM stage. The FAR-TNM score was significantly related to tumor location, tumor size, Bormann types, differentiation, operative type, vascular invasion, nerve invasion, depth of invasion, lymphatic metastasis, and advanced TNM stage. Multivariate Cox regression analysis demonstrated that tumor location, TNM stage, adjuvant chemotherapy, and FAR-TNM score were independent prognostic elements for OS in patients with GC.

CONCLUSIONS

The FAR-TNM score was a valuable independent prognostic indicator for GC patients after surgery, which can help clinicians to assist the treatment and long-term management of patients with gastric cancer.

Establishment of a 7-gene expression panel to improve the prognosis classification of gastric cancer patients

Gastric cancer (GC) ranks fifth in incidence and fourth in mortality worldwide. The high death rate in patients with GC requires new biomarkers for improving survival estimation. In this study, we performed a transcriptome-based analysis of five publicly available cohorts to identify genes consistently associated with prognosis in GC. Based on the ROC curve, patients were categorized into high and low-expression groups for each gene using the best cutoff point. Genes associated with survival (AUC > 0.5; univariate and multivariate Cox regressions, p < 0.05) were used to model gene expression-based scores by weighted sum using the pooled Cox β regression coefficients. Cox regression (p < 0.05), AUC > 0.5, sensitivity > 0.5, and specificity > 0.5 were considered to identify the best scores. Gene set enrichment analysis (KEGG, REACTOME, and Gene Ontology databases), as well as microenvironment composition and stromal cell signatures prediction (CIBERSORT, EPIC, xCell, MCP-counter, and quanTIseq web tools) were performed. We found 11 genes related to GC survival in the five independent cohorts. Then, we modeled scores by calculating all possible combinations between these genes. Among the 2,047 scores, we identified a panel based on the expression of seven genes. It was named GES7 and is composed of CCDC91, DYNC1I1, FAM83D, LBH, SLITRK5, WTIP, and NAP1L3 genes. GES7 features were validated in two independent external cohorts. Next, GES7 was found to recategorize patients from AJCC TNM stages into a best-fitted prognostic group. The GES7 was associated with activation of the TGF-β pathway and repression of anticancer immune cells. Finally, we compared the GES7 with 30 previous proposed scores, finding that GES7 is one of the most robust scores. As a result, the GES7 is a reliable gene-expression-based signature to improve the prognosis estimation in GC.

Construction and validation of a novel nomogram to predict cancer-specific survival in patients with gastric adenocarcinoma

Background and aims

Adenocarcinoma is one of the most common pathological types of gastric cancer. The aims of this study were to develop and validate prognostic nomograms that could predict the probability of cancer-specific survival (CSS) for gastric adenocarcinoma (GAC) patients at 1, 3, and 5 years.

Methods

In total, 7747 patients with GAC diagnosed between 2010 and 2015, and 4591 patients diagnosed between 2004 and 2009 from the Surveillance, Epidemiology, and End Results (SEER) database were included in this study. The 7747 patients were used as a prognostic cohort to explore GAC-related prognostic risk factors. Moreover, the 4591 patients were used for external validation. The prognostic cohort was also divided into a training and internal validation sets for construction and internal validation of the nomogram. CSS predictors were screened using least absolute shrinkage and selection operator regression analysis. A prognostic model was built using Cox hazard regression analysis and provided as static and dynamic network-based nomograms.

Results

The primary site, tumor grade, surgery of the primary site, T stage, N stage, and M stage were determined to be independent prognostic factors for CSS and were subsequently included in construction of the nomogram. CSS was accurately estimated using the nomogram at 1, 3, and 5 years. The areas under the curve (AUCs) for the training group at 1, 3, and 5 years were 0.816, 0.853, and 0.863, respectively. Following internal validation, these values were 0.817, 0.851, and 0.861. Further, the AUC of the nomogram was much greater than that of American Joint Committee on Cancer (AJCC) or SEER staging. Moreover, the anticipated and actual CSS values were in good agreement based on decision curves and time-calibrated plots. Then, patients from the two subgroups were divided into high- and low-risk groups based on this nomogram. The survival rate of high-risk patients was considerably lower than that of low-risk patients, according to Kaplan-Meier (K-M) curves (p<0.0001).

Conclusions

A reliable and convenient nomogram in the form of a static nomogram or an online calculator was constructed and validated to assist physicians in quantifying the probability of CSS in GAC patients.

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.

•

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.

A novel nomogram for predicting survival of patients with poorly differentiated gastric adenocarcinoma

Background

Poorly differentiated gastric adenocarcinoma (PDGA) is a common adenocarcinoma with less glandular structure in gastric cancer. To date, the factors affecting its prognosis remain unclear. In this study, we establish a novel prognostic nomogram for PDGA.

Methods

We screened the Surveillance, Epidemiology, and End Results (SEER) database and downloaded data from PDGA patients who underwent surgery between 2010 and 2015. We explored their clinicopathological characteristics and important prognostic factors such as overall survival (OS), using univariate and multivariate Cox proportional hazards regression analyses, then constructed a prognostic nomogram using the resulting significant variables to predict the OS. We verified performance of the nomogram externally using a separate Chinese set, and further compared its ability as well as the 8^th edition of the American Joint Committee on Cancer (AJCC) staging system to predict prognosis.

Results

A total of 3,887 patients in the SEER database met our inclusion criteria and were therefore included in the analysis. Multivariate analysis showed that age, sex, tumor size, prime site of tumor, T stage, N stage, and M stage were all independent prognostic factors for PDGA. These factors allowed successful establishment of a nomogram model with high predictive power, based on external verification using a Chinese set comprising 632 PDGA patients. The nomogram showed a better discrimination advantage than the 8^th edition of the AJCC staging system in predicting OS (C-index of nomogram vs. AJCC staging for SEER set: 0.707 vs. 0.663; Chinese set: 0.788 vs. 0.713).

Conclusions

The nomogram, established herein, was more accurate in predicting the 1-, 3-, and 5-year OS of PDGA patients than the traditional AJCC TNA staging system. Successful establishment of a PDGA prognostic nomogram is a further step towards individualized and precise treatment of gastric cancer.

Short-term survival and safety of apatinib combined with oxaliplatin and S-1 in the conversion therapy of unresectable gastric cancer

Background

We conducted a single-arm phase II trial to investigate the short-term efficacy and safety of apatinib combined with oxaliplatin and S-1 in the treatment of unresectable gastric cancer.

Patients and methods

Previously untreated patients with unresectable HER-2-negative advanced gastric cancer were selected. All the patients received six cycles of S-1 and oxaliplatin and five cycles of apatinib, which were administered at intervals of three weeks. The surgery was performed after six cycles of drug treatment. The primary endpoints were radical resection (R0) rate and safety. This study was registered with the China Trial Register, number ChiCTR-ONC-17010430 (01/12/2016–01/12/2022).

Results

A total of 39 patients were enrolled. Efficacy evaluation was feasible for 37 patients. One patient achieved complete response (CR, 2.7%), 26 patients achieved partial response (PR, 70.3%), three patients had stable disease (SD, 8.1%) and seven patients had progressive disease (PD, 18.9%). The objective response rate (ORR) was 73.0% and the disease control rate (DCR) was 81.1%. 22 patients underwent surgery, among which 14 patients underwent radical resection (R0), with a R0 resection rate of 63.6%. The 1-year survival rate of the surgical group (22 patients) was 71.1% and the 2-year survival rate was 41.1%. The median survival time was 21 months. The incidence of adverse events (AEs) was 100%. Leucopenia (65.3%) and granulocytopenia (69.2%) were the most common hematological AEs. The most common non-hematological AEs were fatigue (51.3%) and oral mucositis (35.9%).

Conclusion

Apatinib combined with oxaliplatin and S-1 showed good short-term survival and acceptable safety in the conversion therapy of unresectable gastric cancer.

A high level of lncFGD5-AS1 inhibits epithelial-to-Mesenchymal transition by regulating the miR-196a-5p/SMAD6/BMP axis in gastric Cancer

Background

Long non-coding RNA (lncRNA) was a vital factor in the progression and initiation of human cancers. This study found a new lncRNA, FGD5-AS1, which can inhibit EMT process, proliferation, and metastasis in vitro and in vivo.

Methods

qRT-PCR was employed to test the expression of lncFGD5-AS1 in 30 gastric cancer patients’ cancer tissue and para-cancer tissue. Overexpressed lncFGD5-AS1 cells shown sharply decrease of proliferation, migration, and epithelial-mesenchymal transition (EMT). miR-196a-5p/SMAD6 was confirmed as downstream molecular mechanism of lncFGD5-AS1 by expression correlation analysis and mechanism experiments. In vivo study illustrated overexpression of lncFGD5-AS1 suppression tumor growth.

Results

LncFGD5-AS1 served as a ceRNA of miR-196a-5p to release its inhibition on SMAD6, a conventional inhibitor on the BMP pathway. Comparing with normal gastric cancer cells, FGD5-AS1 overexpressed group had fewer migration cells, lower cell viability, and lower EMT transformation rate. Meanwhile, xenografts nude mice injecting with overexpressed-FGD5-AS1 cells also shown smaller tumor weight and volume.

Conclusion

In conclusion, this research supported the first evidence that FGD5-AS1 suppressed proliferation and metastasis in gastric cancer by regulating miR-196a-5p/SMAD6/BMP axis and suggested a potential therapeutic candidate for gastric cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08192-x.

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.

Comparison of S-1 plus oxaliplatin (SOX) and capecitabine plus oxaliplatin (XELOX) as adjuvant chemotherapies for stage II and III gastric cancer after D2 resection: A single-center retrospective study

Background

Capecitabine plus oxaliplatin (XELOX) as adjuvant therapy for gastric cancer (GC) reduces cancer recurrence and improves survival. S‐1 plus oxaliplatin (SOX) is well‐tolerated and effective against advanced GC, and also be used widely in adjuvant treatment. However, data comparing SOX and XELOX as adjuvant treatments are lacking.

Method

Data on treatment modalities, adverse events, recurrence and metastasis were collected from 180 patients with stage II and III GC, who received SOX or XELOX after D2 gastrectomy between January 2012 and December 2015, and analyzed retrospectively. The primary endpoint was 3‐year disease‐free survival (DFS) rate.

Results

Median follow was 52.9 months; 3‐year DFS rate and overall survival (OS) rate were 75.2% and 67.6% (P = 0.359) and 81.2% and 83.3% (P = 0.77) in the SOX and XELOX groups, respectively. There was no significant difference in peritoneal metastasis rates in the SOX and XELOX groups (8.6% vs 15%, respectively; P = 0.232). Compound recurrent disease was associated with significantly shorter OS. Multivariate analysis identified metastatic lymph node ratio (LNR) as an independent prognostic factor for OS (P = 0.036; hazard ratio = 2.875; 95% confidence interval, 1.069–7.729); the LNR ≥17% group had inferior 3‐year OS rate to the LNR <17% group (P = 0.001). The incidence of grades 3 and 4 adverse events was similar in both groups; however, grade ≥2 hand–foot syndrome was significantly less frequent in the SOX group (P = 0.01).

Conclusion

SOX has similar survival benefits to XELOX and is well‐tolerated in Chinese patients with GC following D2 gastrectomy.

Comparing prognostic values of the 7th and 8th editions of the American Joint Committee on Cancer TNM staging system for gastric cancer

Background and Aim:

Our aim was to compare the prognostic value of the American Joint Committee on Cancer (AJCC) 7th and 8th editions staging systems for patients with gastric cancer in China.

Methods:

A total of 1326 gastric cancer patients diagnosed between 2008 and 2012 were included. The discriminative ability of the AJCC 8th and 7th editions was compared using the Harrell’s concordance index (C-index).

Results:

There are two main modifications in the 8th edition. (i) pN3 staging was divided into pN3a and pN3b. The gastric cancer patients with pN3a experienced significantly better overall survival compared with those with pN3b (5-year overall survival: 34.5% vs. 15.6%, P < 0.001) (stratified by pT: pT3: 5-year overall survival: 33.9% vs. 13.2%, P < 0.001; pT4a: 32.8% vs. 16.9%, P = 0.056; pT4b: 17.0% vs. 11.1%, P = 0.048). (ii) Subgroup staging adjustments. The subgroup staging adjustments (T3N3bM0 (IIIB→IIIC), T4aN3aM0 (IIIC→IIIB), T4bN0M0 (IIIB→IIIA), and T4bN2M0 (IIIC→IIIB)) resulted in more gastric cancer patients being accurately staged. Furthermore, the C-index value of the 8th edition tumor node metastasis (TNM) staging system was significantly higher than that of the AJCC 7th TNM staging system to predict the survival of gastric cancer patients (0.701 vs. 0.685, P < 0.001).

Conclusions:

The 8th edition of the TNM staging system is superior to the 7th edition staging system for prediction of survival of gastric cancer patients in China.

Multi-institutional validation of the 8th AJCC TNM staging system for gastric cancer: Analysis of survival data from high-volume Eastern centers and the SEER database

BACKGROUND

The clinical relevance and general applicability of the 8th American Joint Committee on Cancer TNM gastric cancer staging system vs the 7th version have not been examined using datasets from both the East and West.

METHODS

Patients (n = 29 984) treated for gastric adenocarcinoma at two high-volume centers (Severance Hospital [SH] and Gangnam Severance Hospital [GSH]) in Korea and data from the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively analyzed. Survival curves, the performance of tumor staging, and the homogeneity of modified subgroups were compared.

RESULTS

Minute changes were noted in the stage IIB subgroup; most changes were noted in stage III. Applying the 8th staging system facilitated better prediction of survival than applying the 7th version for SH data according to the log-rank test, C-index, and AIC (8444.5 vs 9263.8, 0.796 vs 0.798, and 104152 vs 103909, respectively). Its performance was also superior for GSH and SEER data. In a subgroup analysis of stages IIB to IIIC in SH, GSH, and SEER data, the 8th staging system showed similar or more homogeneous survival for each sub-classification than the 7th version.

CONCLUSION

Compared with the 7th gastric cancer staging system, the newer version more accurately predicted prognosis and stratified subgroups more homogeneously.

Differential gene expression in growth factors, epithelial mesenchymal transition and chemotaxis in the diffuse type compared with the intestinal type of gastric cancer

Gastric cancer (GC) is a highly heterogeneous disease and one of the major causes of cancer-related mortality worldwide. Diffuse-type gastric adenocarcinoma (or poorly cohesive- with independent cells) is characterized by aggressive behavior (rapid invasion, chemoresistance and peritoneal metastasis), as compared with intestinal-subtype adenocarcinoma. Diffuse subtype GC additionally has a substantially increasing incidence rate in Europe and the USA, and was often associated with younger age. Our objective was to analyze the expression and clinical significance of genes involved in several signaling pathways in diffuse-type GC. Tumors samples and non-malignant gastric tissues were obtained from patients with GC (diffuse-type and intestinal-subtype adenocarcinoma). The expression of 33 genes coding for proteins involved in four categories, growth factors and receptors, epithelial-mesenchymal transition, cell proliferation and migration, and angiogenesis was determined by reverse transcription-quantitative polymerase chain reaction. The expression of 22 genes was significantly upregulated in diffuse-type GC and two were downregulated (including CDH1) compared with normal tissues. Among these genes, acompared with intestinal-subtype adenocarcinoma, diffuse-type GC revealed elevated levels of IGF1 and IGF1R, FGF7 and FGFR1, ZEB2, CXCR4, CXCL12 and RHOA, and decreased levels of CDH1, MMP9 and MKI67. The expression of selected genes was compared with other genes and according to clinical parameters. Furthermore, TGF-β expression was significantly increased in linitis, a sub-population of diffusely infiltrating type associated with extensive fibrosis and tumor invasion. Our study identified new target genes (IGF1, FGF7, CXCR4, TG-β and ZEB2) whose expression is associated with aggressive phenotype of diffuse-type GC.

Updates on Management of Gastric Cancer

PURPOSE OF REVIEW

Gastric adenocarcinoma is the fifth most common and the third most lethal cancer worldwide. Surgery is the only chance of cure, but recurrence is common, even with complete resection.

RECENT FINDINGS

Advances in diagnosis and staging, genomic classification, surgical resection and treatment of peritoneal disease, systemic chemotherapy and chemoradiation, and targeted and immune therapies have led to the current multidisciplinary approach to gastric adenocarcinoma. Treatment of gastric cancer is rapidly evolving in an effort to combat this challenging disease.

Ratio-based staging systems are better than the 7th and 8th editions of the TNM in stratifying the prognosis of gastric cancer patients: A multicenter retrospective study

BACKGROUND

The current and the previous editions of the tumor-node-metastasis (TNM) system for gastric cancer (GC; TNM8 and TNM7) have a high risk of stage-migration bias when the node count after gastrectomy is suboptimal. Hence, they are possibly not the optimal staging systems for GC patients. This study aims to compare the TNM with two systems less affected by the stage-migration bias, namely, the lymph nodes ratio (LNR) and the log odds of positive lymph nodes (LODDS), to assess which one is the best in stratifying the prognosis of GC patients.

METHODS

The sample study included 1221 GC patients. Two 7-cluster staging systems based on the combination of pT categories and LNR and LODDS categories (TLNR and TLODDS) were compared with the two last editions of TNM, using the Akaike information criteria, the Bayesian information criteria, and the receiver operating characteristic (ROC) curve graphs. Further validation on an independent sample of 251 patients was carried out.

RESULTS

The univariable and multivariable analyses and the ROC curves detected an advantage of the TLNR and TLODDS systems over the TNM. The TLNR and TLODDS showed the best accuracy both in the subgroup of patients with ≥16 nodes examined. The results were confirmed in the validation analysis.

CONCLUSIONS

TLNR and TLODDS staging systems should be considered a valid implementation of the TNM for the prognostic stratification of GC patients. If these results are confirmed in further studies, the future implementation of the TNM should consider the introduction of the LNR or the LODDS along with the number of metastatic nodes.

Prognostic significance of tumour infiltration growth pattern in patients with advanced gastric cancer

Aims

The prognostic significance of infiltration growth pattern (INF) in patients with gastric cancer (GC) remains controversial. In the present study, we evaluated the impact of INF pattern on the prognosis of patients with advanced GC.

Methods

A total of 1455 patients with advanced GC who underwent curative gastrectomy in our institution were retrospectively analysed. All patients were histopathologically classified as INFa/b and INFc pattern according to the Japanese Classification of Gastric Cancer. The prognostic difference between two patterns was compared and clinicopathological features were analysed.

Results

The prognosis of the patients with INFc pattern was poorer than that of those with INFa/b pattern (5-year disease-free survival, INFa/b: 48.4% vs INFc: 33.5%, p < 0.001), even when they were stratified according to lymph node metastasis and the tumour, node, metastases stage. In addition, the subgroup analysis indicated that INFc pattern was significantly associated with poorer prognosis of T2–T3 stage patients (T2, INFa/b: 72.7% vs INFc: 55.4%; T3, INFa/b: 47.4% vs INFc: 33.5%; p<0.001). However, a similar result was not observed among T4a stage patients (INFa/b: 26.8% vs INFc: 24.8%, p>0.05). The prognosis of T2 stage patients with INFc pattern was similar to that of T3 stage patients with INFa/b pattern (p>0.05). Also, there was no significantly prognostic difference between T3 stage patients with INFc pattern and T4a stage patients (p>0.05). The multivariate analysis indicated that INF pattern was an independent prognostic factor for patients with advanced GC (HR 1.259, 95%CI 1.089 to 1.454).

Conclusion

In view of its prognostic significance, histopathological evaluation of INF pattern in surgically resected specimens should be recommended in patients with advanced GC.

Assessment of the 8th edition of TNM staging system for gastric cancer: the results from the SEER and a single-institution database

AIM

To investigate whether the 8th edition of Tumor, Node, Metastasis (TNM) staging could properly evaluate the prognosis of gastric cancer patients.

METHODS

The prognostic performance between the 7th and 8th edition of TNM staging was compared and clinicopathologic features were analyzed.

RESULTS

The stage shifts in the 8th edition staging resulted in the increased numbers of stage IIIA patients and decreased numbers of stage IIB, stage IIIB and stage IIIC patients. Compared with the previous edition, the 8th edition of TNM staging provided a better prognostic stratification for stage III patients. However, whether it is reasonable to incorporate T4aN2, T4aN3a and T4bN3b into stage IIIA, stage IIIB and stage IIIC respectively, which still need further validation.

CONCLUSION

Despite the obvious superiority, several deficiencies may still exist in the new edition staging. To better provide prognostic information and therapeutic guidance for gastric cancer patients, the TNM staging system should be further improved in the future.

Comparison of the 7th and the 8th AJCC Staging System for Non-metastatic D2-Resected Lymph Node-Positive Gastric Cancer Treated with Different Adjuvant Protocols

PURPOSE

The purpose of this study was to compare prognostic differentiation performances of the 7th and the 8th edition of American Joint Commission on Cancer (AJCC) staging system for gastric cancer (GC) patients.

Materials and Methods

A total of 1,633 GC patients who underwent curative D2 resection followed by adjuvant chemotherapy alone (CA) or concurrent chemo-radiotherapy (CCRT) from 2004 to 2013 were included. Concordance index (c-index) was applied to compare the discriminatory ability.

RESULTS

In the 8th edition, migration of stage was detected in 248 patients (15.2%). Among them, 121 patients were up-staged while 127 patients were down-staged. Overall, there was no statistically significant difference in the discriminatory ability between the 7th and 8th editions. The new edition of staging system, however, showed a trend of better prognostic performance not only in recurrence-free survival (c-index=0.734; 95% confidence interval [CI], 0.706 to 0.762 in the 7th edition vs. c-index=0.740; 95% CI, 0.712 to 0.768 in the 8th edition; p=0.14), but also in overall survival (c-index=0.717; 95% CI, 0.688 to 0.745 in the 7th edition vs. c-index=0.722; 95% CI, 0.694 to 0.751 in the 8th edition; p=0.19), especially in stage III. This finding was repeated in the subgroup analysis regardless of adjuvant CA or CCRT.

CONCLUSION

Generally, the 8th edition of AJCC staging system had failed to show a superior discriminatory ability for curatively D2 resected GC patients than the 7th edition, although there was a trend of better prognostic performance of the new edition, regardless of adjuvant treatment method.

Evaluating TNM stage prognostic ability in a population-based cohort of gastric adenocarcinoma patients in a low-incidence country

OBJECTIVES

TNM stage is the preeminent cancer staging system and a fundamental determinant of disease prognosis. Our goal was to evaluate the predictive power of TNM stage for gastric adenocarcinoma (GAC), in a low-incidence country.

METHODS

A province-wide chart review of GAC patients diagnosed from April 1, 2005 to March 31, 2008 was conducted in Ontario and linked to routinely collected vital status data with a follow-up on March 31, 2012. TNM staging was classified using the sixth and seventh Union International for Cancer Control/American Joint Committee on Cancer editions. Kaplan-Meier and log-rank tests compared stage-stratified survival estimates. Discrimination was evaluated using Harrell's C statistic.

RESULTS

The cohort included 2366 patients. One- and 5-year survival was 43% and 17%. Using the sixth edition, 9% of patients had stage I disease, 5.4% stage II, 7.3% stage III, and 64% stage IV; 15% were not staged. Using the seventh edition, 9% were stage I, 7.7% stage II, 16% stage III, and 54% stage IV; 14% were not staged. Stage-stratified 5-year survival ranged from 68% to 7% with the sixth edition and from 70% to 4% with the seventh edition. Harrell's C statistic was 0.64 (0.63-0.65) for the broad sixth edition staging categories and 0.68 (0.67-0.69) for the broad seventh edition. Discriminative power was similar for the refined stage categories and across multiple subgroup analyses; it was best in non-metastatic patients.

CONCLUSION

Existing staging systems for GAC used in North America predict individualized prognosis poorly. The creation of a more complex prediction tool is necessary to provide accurate and precise prognostication information to oncologists, patients, and their families.

Efficacy after preoperative capecitabine and oxaliplatin (XELOX) versus docetaxel, oxaliplatin and S1 (DOS) in patients with locally advanced gastric adenocarcinoma: a propensity score matching analysis

BACKGROUND

The aim of this study was to compare the efficacies of the XELOX and DOS regimens as preoperative chemotherapy in patients with locally advanced gastric cancer.

METHODS

All cases of locally advanced gastric cancer treated with the XELOX or DOS regimen were reviewed retrospectively. Propensity score matching (PSM) was carried out to reduce selection bias based on age, gender, location, Lauren type, carcinoembryonic antigen level, clinical tumor stage, and clinical node stage.

RESULTS

From January 2010 to December 2016, 248 patients were matched; 159 of them received the XELOX regimen and 89 the DOS regimen. The response rates in the XELOX and DOS groups were 34.5 and 38.1%, respectively (P = 0.823). After four cycles of chemotherapy, 111 patients (69.8%) in the XELOX group and 65 patients (73.0%) in the DOS group underwent radical surgery (P = 0.485). The median progression-free survival (33.0 months vs. 18.7 months, P = 0.0356) and the median overall survival (43.8 months vs. 29.1 months, P = 0.0003) were longer for patients who received the DOS regimen than for those who received the XELOX regimen. The occurrence of grade 3 to 4 toxicity was similar in the two groups.

CONCLUSIONS

For locally advanced gastric cancer patients, the DOS regimen showed more benefit than the XELOX regimen as preoperative chemotherapy, without any added toxicity effects.

MicroRNA-421 promotes the proliferation and metastasis of gastric cancer cells by targeting claudin-11

The present study aimed to evaluate the expression of microRNA (miR)-421 in gastric cancer and to investigate its biological function and underlying mechanism of action in the development of gastric cancer. The expression of miR-421 was measured in 60 pairs of clinically removed gastric cancer tissues and matched adjacent normal gastric tissues by reverse transcription-quantitative polymerase chain reaction. In addition, following transfection with an miR-421 inhibitor to suppress the expression of miR-421, the proliferation, migration and cell cycle distribution of human gastric carcinoma MKN28/MKN74 cells were determined by cell counting, Transwell and flow cytometry assays. The target gene of miR-421 was also predicted using bioinformatic analysis and verified by dual-luciferase reporter gene assay and western blot analysis. Furthermore, overexpression of the miR-421 target protein was induced in MKN28/MKN74 cells to determine its function. It was observed that miR-421 was significantly upregulated in gastric cancer tissues and that the expression of miR-421 was associated with lymph node metastasis and the clinical stage of gastric cancer (all P<0.05). Claudin11 (CLDN11) was predicted and verified as a direct target of miR-421. In vitro experiments demonstrated that inhibition of miR-421 expression suppressed the proliferation and metastasis of MKN28/MKN74 cells and induced G1/S-phase cell cycle arrest (all P<0.05). Analagous results were observed in MKN28/MKN74 cells following overexpression of the CLDN11 protein. Collectively, these data suggest that miR-421 may promote the proliferation, invasion and metastasis of gastric cancer by inhibiting the expression of CLDN11.