Survival comparison in gastric cancer patients between 7th and 8th edition of the AJCC TNM staging system: The first western single center experience

Normalization weighted combination scores re-evaluate TNM staging of gastric cancer: a retrospective cohort study based on a multicenter database

BACKGROUND

The pathological depth of tumor invasion (pT) and lymph node metastasis (pN) are critical independent prognostic factors for patients with gastric cancer (GC), representing effective methods for evaluating prognosis. In this study, the authors employed a normalization weight combination score to calculate the weight ratio of the pT stage and pN stage. Subsequently, the authors established a novel weighted TN (wTN) staging model based on these T and N weights, evaluating its prognostic capacity.

METHODS

This study utilized a training cohort from A Medical University Cancer Hospital and a validation cohort from the SEER database. Least absolute shrinkage and selection operator (LASSO) and Cox regression were employed to screen clinical characteristics. Multivariate linear regression and cluster analysis calculated the weight ratio of T stage and N stage in the training and validation cohorts, respectively, followed by re-staging. Prognostic value was evaluated using C-index, likelihood ratio, Wald, and Score tests for wTN stage and tumor-node-metastasis (TNM) stage. A nomogram model was developed, and accuracy was assessed using receiver operating characteristic curve (ROC), decision curve analysis (DCA), and restricted cubic spline (RCS) analyses.

RESULTS

LASSO was used for initial screening, selecting eight potential features for Cox analysis. Age, tumor size, metastasis lymph nodes (MLNs), and tumor location were confirmed as independent prognostic factors. wTN was calculated in the training and validation cohorts, and nomograms were established with the independent factors. N stage had a higher weight proportion than T stage in both cohorts (0.625/0.375 in training cohort, 0.556/0.444 in validation cohort). wTN outperformed the 8th TNM stage in C-index, likelihood ratio, Wald, and Score tests in the training cohort, with successful validation in the validation cohort. Stratified analysis of distinct pathological types further demonstrates that wTN staging exhibits superior prognostic performance.

CONCLUSION

The wTN staging model based on T stage and N stage weights has a good prognostic value for GC patients. The same conclusion was obtained in different pathological stratification.

A Comprehensive Review of Prognostic Factors in Patients with Gastric Adenocarcinoma

Gastric adenocarcinoma remains associated with a poor long-term survival, despite recent therapeutical advances. In most parts of the world where systematic screening programs do not exist, diagnosis is often made at advanced stages, affecting long-term prognosis. In recent years, there is increasing evidence that a large bundle of factors, ranging from the tumor microenvironment to patient ethnicity and variations in therapeutic strategy, play an important role in patient outcome. A more thorough understanding of these multi-faceted parameters is needed in order to provide a better assessment of long-term prognosis in these patients, which probably also require the refinement of current staging systems. This study aims to review existing knowledge on the clinical, biomolecular and treatment-related parameters that have some prognostic value in patients with gastric adenocarcinoma.

Nomogram-Based Prognostic Evaluation of Gastric Cancer Patients with Low Counts of Examined Lymph Nodes Outperforms the Predictive Ability of the 7th and 8th Editions of the American Joint Committee on Cancer Staging System

BACKGROUND

The American Joint Committee on Cancer (AJCC) staging system has limited accuracy in predicting survival of gastric cancer patients with inadequate counts of evaluated lymph nodes (LNs). We therefore aimed to develop a prognostic nomogram suitable for clinical applications in such cases.

METHODS

A total of 1511 noncardia gastric cancer patients treated between 1990 and 2010 in the academic surgical center were reviewed to compare the 7^th and 8^th editions of the AJCC staging system. A nomogram was developed for the prediction of 5-year survival in patients with less than 16 LNs evaluated (n = 546). External validation was performed using datasets derived from the Polish Gastric Cancer Study Group (n = 668) and the SEER database (n = 11,225).

RESULTS

The 8th edition of AJCC staging showed better overall discriminatory power compared to the previous version, but no improvement was found for patients with < 16 evaluated LNs. The developed nomogram had better concordance index (0.695) than the former (0.682) or latest (0.680) staging editions, including patients subject to neoadjuvant treatment, and calibration curves showed excellent agreement between the nomogram-predicted and actual survival. High discriminatory power was also demonstrated for both validation cohorts. Subsequently, the nomogram showed the best accuracy for the prediction of 5-year survival through the time-dependent ROC curve analysis in the training and validation cohorts.

CONCLUSIONS

A clinically relevant nomogram was built for the prediction of 5-year survival in patients with inadequate numbers of LNs evaluated in surgical specimens. The predictive accuracy of the nomogram was validated in two Western populations.

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.

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.

Development and Validation of a Prognostic Nomogram for Gastric Signet Ring Cell Carcinoma: A Multicenter Population-Based Study

Background

Gastric signet ring cell carcinoma (GSRCC) is a rare disease associated with poor prognosis. A prognostic nomogram was developed and validated in this study to assess GSRCC patients’ overall survival (OS).

Methods

Patients diagnosed with GSRCC from the Surveillance, Epidemiology, and End Results (SEER) database (2004–2016) and the First Hospital of China Medical University (CMU1h) were enrolled in this retrospective cohort study. Univariate and multivariate COX analysis was used to determine independent prognostic factors to construct the prognostic nomogram. Predictions were evaluated by the C-index and calibration curve. In addition, the receiver operating characteristic (ROC) curve, decision curve analysis (DCA), and Kaplan-Meier analysis were employed to assess the clinical utility of the survival prediction model.

Results

Patients were classified into two cohorts. We randomly divided patients in the SEER database and CMU1h cohort into a training group (n=3068, 80%) and a validation group (n=764, 20%). Age, race, T stage, N stage, M stage, therapy, and tumor size were significantly associated with the prognosis of GSRCC patients. On this basis, a nomogram was constructed, with a C-index in the training and the validation cohorts at 0.772 (95% CI: 0.762–0.782) and 0.774 (95% CI: 0.752–0.796), respectively. The accuracy of the generated nomogram was verified through calibration plots. Similarly, compared with the traditional AJCC staging system, the results of the area under curve (AUC) calculated by ROC, DCA, and Kaplan-Meier curves, demonstrated a good predictive value of the constructed nomogram, compared to the traditional AJCC staging system.

Conclusion

In the present study, seven independent prognostic factors of GSRCC were screened out. The established nomogram models based on seven variables provided a visualization of each prognostic factor’s risk and assisted clinicians in predicting the 1-, 3-, and 5-year OS of GSRCC.

Impact of the 8th edition of the AJCC TNM classification on gastric cancer prognosis-study of a western cohort

Introduction

The 8th edition of the American Joint Committee on Cancer (AJCC) TNM classification for gastric cancer introduced changes, mainly in stage III, with the incorporation of the pN3 sub-classification in the final staging group. The goal was to compare the 7th and 8th editions to evaluate the discriminative capacity of the new edition.

Methods

This study was a retrospective review of patients with gastric cancer treated with surgery in 2013 and 2014.

Results

We analysed 310 patients, with a median age of 66 years and out of which 55.5% were male. The most commonly performed surgery was subtotal gastrectomy (n = 158; 51%), with a median of 30 lymph nodes removed. With a median follow-up of 39.5 months, the 1- and 3-year overall survival (OS) was 82% and 59%, respectively. In stage III (n = 115), there was stage migration in 40 cases (34.8%), with upstage in 11 cases and downstage in 29 cases. In this group, there was a statistically significant difference in OS between N3a and N3b patients (p = 0.002), as well as a statistically significant difference in OS between stages IIIA, IIIB and IIIC when the 8th edition was applied (p = 0.001), which was not verified with the 7th edition (p = 0.057). In multivariate analysis, both extracapsular extension and N classification from TNM were independent prognostic factors (p = 0.033 and p = 0.024, respectively).

Conclusion

The 8th edition of the AJCC TNM classification allows for a better prognostic refinement, namely in the new stage III groups after the stratification of lymph node disease in N3a and N3b. Factors that evaluate the biological behaviour of the disease remain excluded from this edition, such as extracapsular extension, which had a prognostic impact in our series.

Which Nutritional Scoring System Is More Suitable for Evaluating the Short- or Long-Term Prognosis of Patients with Gastric Cancer Who Underwent Radical Gastrectomy?

OBJECTIVE

To evaluate the effects of three nutritional scoring systems: Prognostic Nutritional Index (PNI), Controlling Nutritional Status (CONUT), and Naples Prognostic Score (NPS) on the short- or long-term prognosis of gastric cancer (GC) patients who underwent radical gastrectomy.

METHODS

The clinicopathological data of 2182 patients who underwent radical gastrectomy at the Fujian Medical University Union Hospital (FMUUH) from 2009 to 2014 were retrospectively analyzed. The effects of the PNI, CONUT, and NPS on the short- or long-term prognosis of GC patients were analyzed.

RESULTS

Overall, 359 (16.5%) patients had postoperative complications. There was no significant association between the PNI, CONUT, and NPS and postoperative complications (P > 0.05); however, high CONUT and NPS were significantly associated with severe postoperative complications (P < 0.05). Univariate analysis showed that PNI, CONUT, and NPS were all associated with overall survival (OS) (P < 0.001). However, multivariate analysis showed that only PNI was an independent risk factor for OS (P = 0.004), and the 5-year OS rate in the low PNI group was significantly lower than that in the normal PNI group (55.5% vs 75.4%, P < 0.05). The area under the curve (AUC) and the c-index of PNI were significantly higher than those of CONUT and NPS. The prognostic efficiency of combining PNI and TNM stage was also significantly better than that of TNM staging alone (P < 0.05).

CONCLUSION

The current study demonstrated that CONUT and NPS are important for assessing the risk of severe postoperative complications. However, PNI is an independent risk factor for the long-term prognosis of GC patients who underwent radical gastrectomy and can improve the prognostic efficiency of TNM staging.

Prognostic Implications of Novel Gene Signatures in Gastric Cancer Microenvironment

Background

Increasing studies have shown the important clinical role of immune and stromal cells in gastric cancer microenvironment. Based on information of immune and stromal cells in The Cancer Genome Atlas, this study aimed to construct a prognostic risk assessment model for gastric cancer.

Material/Methods

Based on the immune/structural scores, differentially expressed genes (DEGs) were filtered and analyzed. Afterwards, DEGs associated with prognosis were screened and the risk assessment model was constructed in the training set. Moreover, the validity of the model was verified both in the testing set and the overall sample.

Results

In this study, patients were divided into high-score and low-score groups based on immune/stromal score, and 919 DEGs were identified. By applying least absolute shrinkage and selection operator (LASSO) and Cox analysis, 10 mRNAs were selected to form a prognostic risk assessment model, risk score=(0.294*SLC17A9) + (−0.477*FERMT3) + (0.866*NRP1) + (0.350*MMRN1) + (0.381*RNASE1) + (0.189*TRIB3) + (0.230*PGAP3) + (0.087*MAGEA3) + (0.182*TACR2) + (0.368*CYP51A1). In the training set, the low-risk group divided by the model was found to have better overall survival, and the prediction efficiency of the model was demonstrated to be good. Multivariate Cox analysis indicated that the model could work as a prognostic factor independently. Similar results were shown in the testing group and overall patients cohort group. Finally, the risk assessment model and other clinical variables were integrated to construct a nomogram.

Conclusions

In general, this study constructs a prognostic risk assessment model for gastric cancer, which could improve the prognosis stratification of patients combined with other clinical indicators.

New prognostic western score predicting survival after curative resection of gastric cancer

The aim of our study was to develop a prognostic score for gastric cancer patients who underwent R0 resection with curative intent, to identify high-risk patients. Three thirty three patients curatively operated for gastric adenocarcinoma were enrolled in the study. To define our prognostic score pre-operative inflammation sieric markers such as neutrophil to lymphocytes ratio, platelet count, platelet to lymphocytes ratio, and other clinical pathological and surgical characteristics of our patients such as albumin preoperative level, CRP sieric level, hystological Lauren's subtype, tumor location, lymphonodal status were analyzed. Prognostic factors predicting OS were analyzed using Cox proportional hazards models and a prognostic score was built. 5Y-OS was 42% with a median survival of 41 months. The multivariate analysis identified four independent prognostic factors: preoperative albumin level (HR 2.5), preoperative N/L ratio (HR 2.4), Diffuse Lauren histological subtype (HR 1.5) and TNM stage III and IV (HR 1.2). According to the relative risk of each variable we construct a prognostic score and validated it internally. Four risk classes were built and patients were statistically different stratifying according to them. More important the stratification was maintained also when patients were subdivided according to the pathological stage. In summary, we were able to construct a prognostic score that could be easily used in all the clinical contests, being it cheap and prompt. Our results, however, need to be externally validated, by a major center to be introduced into the clinical practice.

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.