Which staging system better predicts 10-year survival for gastric cancer? A study using an international multicenter database

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.

Which Staging System Is More Suitable for Gastric Neuroendocrine Cancer and Mixed Adenoneuroendocrine Carcinomas? A Multicenter Cohort Study

PURPOSE

To evaluate whether the European Neuroendocrine Tumor Society (ENETS) system or the 8th American Joint Committee on Cancer (AJCC) staging manual are suitable for gastric neuroendocrine carcinomas and/or mixed adenoneuroendocrine carcinomas (G-NECs/MANECs).

METHODS

Patients in a multicentric series with G-NEC/MANEC who underwent curative-intent surgical resection for a primary tumor were included. An optimal staging system was proposed base on analysis of the T and N status and validated by the SEER database.

RESULTS

Compared with the ENETS system, the survival curves of the T category and N category in the 8th AJCC system were better separated and distributed in a more balanced way, but the survival curves of T2 vs. T3, N0 vs. N1, and N3a vs. N3b overlapped. For the T category, the 8th AJCC T category was modified by combining T2 and T3, which was consistent with the T category in the 6th AJCC manual for GC. For the N category, the optimal cut-off values of metastatic lymph nodes using X-tile were also similar to those of the N category in the 6th AJCC system. The Kaplan-Meier plots of the 6th AJCC system showed statistically significant differences between individual substages. Compared with the other 2 classifications, the 6th AJCC system also showed superior prognostic stratification. Similar results were obtained in both multicentric and SEER validation sets.

CONCLUSIONS

Compared to the 8th AJCC and ENETS systems, the 6th AJCC staging system for GC is more suitable for G-NEC/MANEC and can be adopted in clinical practice.

Changing trends of clinicopathologic features and survival duration after surgery for gastric cancer in Northeast China

BACKGROUND

Through analyzing the data from a single institution in Northeast China, this study revealed the possible clinicopathologic characteristics that influence the prognosis of patients with gastric cancer (GC).

AIM

To evaluate the changing trends of clinicopathologic features and survival duration after surgery in patients with GC in Northeast China, which is a high-prevalence area of GC.

METHODS

The study analyzed the difference in clinicopathologic features and survival duration after surgery of 5887 patients who were histologically diagnosed with GC at the Harbin Medical University Cancer Hospital. The study mainly analyzed the data in three periods, 2000 to 2004 (Phase 1), 2005 to 2009 (Phase 2), and 2010 to 2014 (Phase 3).

RESULTS

Over time, the postoperative survival rate significantly increased from 2000 to 2014. In the past 15 years, compared with Phases 1 and 2, the tumor size was smaller in Phase 3 (P < 0.001), but the proportion of high-medium differentiated tumors increased (P < 0.001). The proportion of early GC gradually increased from 3.9% to 14.4% (P < 0.001). A surprising improvement was observed in the mean number of retrieved lymph nodes, ranging from 11.4 to 27.5 (P < 0.001). The overall 5-year survival rate increased from 24% in Phase 1 to 43.8% in Phase 3. Through multivariate analysis, it was found that age, tumor size, histologic type, tumor-node-metastasis stage, depth of invasion, lymph node metastasis, surgical approach, local infiltration, radical extent, number of retrieved lymph nodes, and age group were independent risk factors that influenced the prognosis of patients with GC.

CONCLUSION

The clinical features of GC in Northeast China changed during the observation period. The increasing detection of early GC and more standardized surgical treatment effectively prolonged lifetimes.

Development and validation of an artificial neural network prognostic model after gastrectomy for gastric carcinoma: An international multicenter cohort study

BACKGROUND

Recently, artificial neural network (ANN) methods have also been adopted to deal with the complex multidimensional nonlinear relationship between clinicopathologic variables and survival for patients with gastric cancer. Using a multinational cohort, this study aimed to develop and validate an ANN-based survival prediction model for patients with gastric cancer.

METHODS

Patients with gastric cancer who underwent gastrectomy in a Chinese center, a Japanese center, and recorded in the Surveillance, Epidemiology, and End Results database, respectively, were included in this study. Multilayer perceptron neural network was used to develop the prediction model. Time-dependent receiver operating characteristic (ROC) curves, area under the curves (AUCs), and decision curve analysis (DCA) were used to compare the ANN model with previous prediction models.

RESULTS

An ANN model with nine input nodes, nine hidden nodes, and two output nodes was constructed. These three cohort's data showed that the AUC of the model was 0.795, 0.836, and 0.850 for 5-year survival prediction, respectively. In the calibration curve analysis, the ANN-predicted survival had a high consistency with the actual survival. Comparison of the DCA and time-dependent ROC between the ANN model and previous prediction models showed that the ANN model had good and stable prediction capability compared to the previous models in all cohorts.

CONCLUSIONS

The ANN model has significantly better discriminative capability and allows an individualized survival prediction. This model has good versatility in Eastern and Western data and has high clinical application value.

Modified staging classification of gallbladder carcinoma on the basis of the 8th edition of the American Joint Commission on Cancer (AJCC) staging system

PURPOSE

The 8th edition of the American Joint Commission on Cancer (AJCC) Staging System for gallbladder cancer (GBC) has been used in clinical practice, but we have found some deficiencies in this edition.

METHODS

Survival analyses were performed to evaluate the application of various editions of the AJCC staging systems using the Surveillance, Epidemiology, and End Results (SEER) database (N = 9616 patients) and Fudan University Zhongshan Hospital (FUZH) database (N = 327 patients). A modified staging system was proposed based on the 8th edition of the AJCC Staging System.

RESULTS

Although all N2 diseases were grouped into stage IVB as M1 in the 8th edition, some patients with N2 diseases could undergo R0 resection, and had longer survival than patients with M1 diseases had in both cohorts (p < 0.001 in SEER, p = 0.041 in FUZH). Furthermore, in the SEER database, stage IIIA patients aberrantly had poorer survival than stage IIIB patients had (p < 0.001). Therefore, we proposed a modified staging system by rearranging the substages. N2 disease was subdivided and reappraised according to T stage, and the aberrant survival reversal of stage IIIA and stage IIIB disease was also corrected. Through our modification, the C-index of the 8th AJCC Staging System was elevated from 0.596 [95% confidence interval (CI): 0.585-0.607] to 0.623 (95% CI: 0.612-0.634) for local disease in the SEER cohort. Similar findings were also observed in the FUZH cohort.

CONCLUSION

Our modified 8th AJCC Staging System is more suitable for GBC and could be adopted for clinical practice.

A novel TNM staging system for gastric cancer based on the metro-ticket paradigm: a comparative study with the AJCC-TNM staging system

BACKGROUND

The metro-ticket prognostic tool for hepatocellular carcinoma has been proven to predict outcome, but a similar concept has not been investigated for GC. The objective of the current study was to apply the principles of the metro-ticket paradigm to develop a novel TNM staging system (nTNM) for gastric cancer (GC).

METHODS

The nTNM considered the distance from the origin on a Cartesian plane incorporating the pN (x-axis) and pT (y-axis) stages. GC patients undergoing radical resection at Fujian Medical University Union Hospital (FMUUH) (n = 4267) were included. The nTNM was validated using 2 external cohorts from the Sun Yat-sen University Cancer Center (SYSUCC) (n = 1800) and Surveillance, Epidemiology, and End Results (SEER) (n = 3227) databases.

RESULTS

nTNM classes with the same distance from the origin have same stage; the stage increases with this distance. Among all patients, 48.0% (n = 2049) were restaged in the nTNM compared with the 7th edition of the AJCC-TNM classification; 26.2% (n = 1116) were downstaged in the nTNM compared with the 8th edition. The nTNM provides significant survival differences between stages (all P < 0.001). The survival difference between stages IB and IIA was especially large for the nTNM (P < 0.001) compared to the 7th and 8th editions (P = 0.073). The concordance index and hazard ratio increased successively with the nTNM stage. Similar findings were observed in both external cohorts.

CONCLUSION

Compared with the AJCC-TNM classification, the nTNM for GC is easier to remember and provides some improvements; therefore, the nTNM may be considered for adoption in future editions of the AJCC-TNM classification.

Implication of lymph node staging in migration and different treatment strategies for stage T2N0M0 and T1N1M0 resected gastric cancer: a SEER population analysis

PURPOSE

The purpose of this study was to explore the differences between stage T2N0M0 and stage T1N1M0 gastric cancer (GC) and to identify the necessity of adjuvant treatment (AT) for these stages.

METHODS

Between years 2004 and 2015, 1971 stage IB GC patients who underwent radical surgery were recruited using the Surveillance, Epidemiology and End Results database. We conducted univariate/multivariate analyses, the propensity score matching and evaluated gastric cancer-specific survival (GCSS) and overall survival (OS) with the log-rank test.

RESULTS

T1N1M0 had a significantly worse survival than T2N0M0 in both GCSS and OS before and after the propensity score matching. Examined lymph nodes (ELN) ≤ 15 and T1N1M0 were independent risk factors for worse GCSS and OS in stage IB GC. The absence of adjuvant chemotherapy (CT) was an independent risk factor for worse GCSS and OS in T1N1M0 but not in T2N0M0. AT demonstrated similar GCSS and OS with surgery alone (SA) for T2N0M0 but better survival for T1N1M0. Compared to CT and adjuvant chemoradiotherapy (CRT) group, SA demonstrated significantly worse GCSS and OS for T1N1M0. There was no significant difference between CT and CRT in both T2N0M0 and T1N1M0 stages. T2N0M0 had a better survival than T1N1M0 in ELN ≤ 15 subgroup. However, similar survival was demonstrated in ELN > 15 subgroup.

CONCLUSIONS

T2N0M0 GC has a better survival rate than T1N1M0 GC when ELN are ≤ 15. Moreover, T2N0M0 GC may not benefit from AT. T1N1M0 GC requires CT but not adjuvant radiotherapy.

Gastric Cancer Is the Leading Cause of Death in Italian Adult Patients With Common Variable Immunodeficiency

An increased prevalence of malignant lymphoma and of gastric cancer has been observed in large cohorts of patients with common variable immunodeficiency (CVID), the most frequently symptomatic primary immunodeficiency. Surveillance strategies for cancers in CVID should be defined based on epidemiological data. Risks and mortality for cancers among 455 Italian patients with CVID were compared to cancer incidence data from the Italian Cancer Registry database. CVID patients showed an increased cancer incidence for all sites combined (Obs = 133, SIR = 2.4; 95%CI = 1.7–3.5), due to an excess of non-Hodgkin lymphoma (Obs = 33, SIR = 14.3; 95%CI = 8.4–22.6) and of gastric cancer (Obs = 25; SIR = 6.4; 95%CI = 3.2–12.5). CVID patients with gastric cancer and lymphoma had a worse survival in comparison to cancer-free CVID (HR: 4.8, 95%CI: 4.2–44.4 and HR: 4.2, 95%CI: 2.8–44.4). Similar to what observed in other series, CVID-associated lymphomas were more likely to be of B cell origin and often occurred at extra-nodal sites. We collected the largest case-series of gastric cancers in CVID subjects. In contrast to other reports, gastric cancer was the leading cause of death in CVID. Standardized mortality ratio indicated a 10.1-fold excess mortality among CVID patients with gastric cancer. CVID developed gastric cancer 15 years earlier than the normative population, but they had a similar overall survival. Only CVID diagnosed at early stage gastric cancer survived >24 months. Stomach histology from upper endoscopy performed before cancer onset showed areas of atrophic gastritis, intestinal metaplasia or dysplasia. CVID patients might progress rapidly to an advanced cancer stage as shown by patients developing a III-IV stage gastric cancer within 1 year from an endoscopy without signs of dysplasia. Based on high rate of mortality due to gastric cancer in Italian CVID patients, we hereby suggest a strategy aimed at early diagnosis, based on regular upper endoscopy and on Helicobacter pylori infection treatment, recommending an implementation of national guidelines.