Validation of the prognostic impact of the new tumor-node-metastasis clinical staging in patients with gastric cancer

Development and Validation of an AI-Based Multimodal Model for Pathological Staging of Gastric Cancer Using CT and Endoscopic Images

RATIONALE AND OBJECTIVES

Accurate preoperative pathological staging of gastric cancer is crucial for optimal treatment selection and improved patient outcomes. Traditional imaging methods such as CT and endoscopy have limitations in staging accuracy.

METHODS

This retrospective study included 691 gastric cancer patients treated from March 2017 to March 2024. Enhanced venous-phase CT and endoscopic images, along with postoperative pathological results, were collected. We developed three modeling approaches: (1) nine deep learning models applied to CT images (DeepCT), (2) 11 machine learning algorithms using handcrafted radiomic features from CT images (HandcraftedCT), and (3) ResNet-50-extracted deep features from endoscopic images followed by 11 machine learning algorithms (DeepEndo). The two top-performing models from each approach were combined into the Integrated Multi-Modal Model using a stacking ensemble method. Performance was assessed using ROC-AUC, sensitivity, and specificity.

RESULTS

The Integrated Multi-Modal Model achieved an ROC-AUC of 0.933 (95% CI, 0.887-0.979) on the test set, outperforming individual models. Sensitivity and specificity were 0.869 and 0.840, respectively. Various evaluation metrics demonstrated that the final fusion model effectively integrated the strengths of each sub-model, resulting in a balanced and robust performance with reduced false-positive and false-negative rates.

CONCLUSION

The Integrated Multi-Modal Model effectively integrates radiomic and deep learning features from CT and endoscopic images, demonstrating superior performance in preoperative pathological staging of gastric cancer. This multimodal approach enhances predictive accuracy and provides a reliable tool for clinicians to develop individualized treatment plans, thereby improving patient outcomes.

DATA AVAILABILITY

The data presented in this study are available on request from the corresponding author. The data are not publicly available due to ethical reasons. All code used in this study is based on third-party libraries and all custom code developed for this study is available upon reasonable request from the corresponding author.

Added value of pretreatment CT-based Node-RADS score for predicting survival outcome of locally advanced gastric cancer: compared with clinical N stage

OBJECTIVES

The Node Reporting and Data System (Node-RADS) offers a reliable framework for lymph node assessment, but its prognostic significance remains unexplored. This study aims to investigate the added prognostic value of Node-RADS in patients with locally advanced gastric cancer (LAGC) undergoing neoadjuvant chemotherapy (NAC) followed by gastrectomy.

MATERIALS AND METHODS

This single-center retrospective study included 118 patients with LAGC underwent NAC and gastrectomy. The maximum Node-RADS score and the number of metastatic lymph node stations (defined as LNM-Station) were evaluated on pretreatment CT. The pretreatment Node-RADS-CT and Node-RADS-integrated models were developed using Cox regression to predict overall survival (OS) and disease-free survival (DFS). The pretreatment cN-CT models, cN-integrated models, as well as post-NAC pathological models were also developed in comparison. The performance of the models was assessed in terms of discrimination, calibration and clinical applicability.

RESULTS

The LNM-Station was significantly associated with OS and DFS (all p < 0.05). The Node-RADS-CT model showed higher Harrell's consistency index (C-index) than cN-CT model (0.755 vs. 0.693 for OS, p = 0.017; 0.759 vs. 0.706 for DFS, p = 0.018). The Node-RADS-integrated model also achieved higher C-index than cN-integrated model (0.771 vs. 0.731 for OS, p = 0.091; 0.773 vs. 0.733 for DFS, p = 0.053). The net reclassification improvement (NRI) of the Node-RADS-integrated model at 5 years was 0.379 for OS and 0.364 for DFS (all p < 0.05). The integrated discrimination improvement (IDI) of the Node-RADS-integrated model was 0.103 for OS and 0.107 for DFS (all p < 0.05). The C-indices (OS: 0.745; DFS: 0.746) of pathological models were slightly lower than those of Node-RADS-based models (all p > 0.05).

CONCLUSION

The baseline Node-RADS score and LNM-Station were effective prognostic indicators for LAGC. The pretreatment CT Node-RADS-based models can offer added prognostic value for LAGC, compared with clinical N stage.

Influence of visceral adipose tissue on the accuracy of tumor T-staging of gastric cancer in preoperative CT

OBJECTIVES

To evaluate the impact of the visceral adipose tissue (VAT) area and density on the accuracy of tumor T-staging of gastric cancer in preoperative computed tomography (CT).

METHODS

This study included 136 patients with gastric cancer in our research center from January 2021 to June 2022. The patients were divided into two groups based on their postoperative pathological results: accurate-staging (matched T-staging evaluated by preoperative CT and postoperative pathology) and inaccurate-staging (unmatched T-staging evaluated by preoperative CT and postoperative pathology) groups. Preoperative CT was performed to assess the VAT area and density, and logistic regression was employed to evaluate the effect of VAT on the accuracy of preoperative-CT-evaluated T-staging of patients with gastric cancer.

RESULTS

The accurate-staging group had a significantly higher VAT area (134.64 ± 70.55 cm2 vs 95.44 ± 66.18 cm2, P = 0.003) and significantly lower VAT density (-95.05 ± 12.28 Hounsfield Units [HU] vs - 89.68 ± 13.26 HU, P = 0.027) than the inaccurate-staging group. A low VAT area (P = 0.002) and tumor located in the upper stomach (P = 0.019) were significantly associated with and were independent risk factors for the error of CT-evaluated T-staging. Compared to a VAT area ≥ 81.04 cm2, which was used as a reference, the odds ratio (OR) of a VAT area < 81.04 cm2 for the probability of T-staging mis-assessment was 4.455 (95% confidence interval [CI]: 1.728-11.485).

CONCLUSIONS

A low VAT area in patients with gastric cancer had adverse effects on preoperative CT-evaluated T-staging.

Dynamic monocyte changes as prognostic indicators in operable gastric cancer: a retrospective cohort analysis

Objective

This study aims to elucidate the relationship between postoperative monocyte count and gastric cancer prognosis. We introduce a standardized monocyte ratio (MMR) to predict postoperative survival rates in gastric cancer patients effectively.

Methods

A test cohort was created to develop and evaluate the pre- and postoperative MMR as a mortality predictor in gastric cancer patients. We used Kaplan-Meier survival analysis, complemented by univariate and multivariate analyses. The predictive utility of MMR was assessed via time-dependent ROC curves and decision-curve analysis.

Results

The sample distributions in both cohorts were similar. The MMR showed high predictive value and significant clinical benefits in 1, 3, and 5-year overall survival (OS) assessments. These findings enhance understanding of prognosis and aid in developing more precise treatment plans.

Conclusions

MMR is confirmed as an independent factor in predicting overall survival in gastric cancer patients, proving to be a reliable and cost-effective prognostic indicator.

Sedated and unsedated gastroscopy has no influence on the outcomes of patients with gastric cancer: a retrospective study

BACKGROUND

Different anesthetic drugs and techniques may affect survival outcomes for gastric cancer (GC) after surgery. In this study, we investigated the association between sedated and unsedated gastroscopy on survival outcomes in patients with GC after surgery.

METHODS

This was a retrospective study of patients who were diagnosed with GC by gastroscopy and underwent gastrectomy from January 2013 to December 2017. They were grouped based on the examination modality: propofol-based sedated gastroscopy or unsedated gastroscopy. Propensity score matching (PSM) was used to balance the baseline variables. Survival outcomes and distant metastases were compared between these two groups.

RESULTS

Finally, 673 patients were enrolled, 160 in the sedated gastroscopy group and 513 in the unsedated gastroscopy group. After PSM, there were 160 patients in each group. There was no significant difference in overall survival outcomes in the sedated gastroscopy group compared to the unsedated gastroscopy group before PSM (HR = 0.761, 95% CI: 0.531-1.091, P = 0.139) or after PSM (HR = 0.874, 95% CI: 0.564-1.355, P = 0.547). There was no significant difference in the incidence of distant metastases between the two groups before PSM (16.9% vs. 20.7%, P = 0.294) or after PSM (16.9% vs. 23.8%, P = 0.126). To confirm that our patients behaved similarly to other studies, we performed a multivariate analysis and the results showed that sex, pathological TNM stage, Borrmann type, adjuvant treatment, and surgical resection range were all independent factors affecting survival outcomes in our patients.

CONCLUSION

Our results showed no significant difference in the effects of sedated gastroscopy vs. unsedated gastroscopy on survival outcomes or distant metastases of patients after gastrectomy for GC.

Inflammation-related markers and prognosis of alpha-fetoprotein producing gastric cancer

BACKGROUND

Inflammation-related markers including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI) and prognostic nutritional index (PNI) could reflect tumor immune microenvironment and predict prognosis of cancers. However, it had not been explored in alpha-fetoprotein (AFP) producing gastric cancer (GC).

AIM

To determine the predictive value of inflammation-related peripheral blood markers including as NLR, PLR, MLR, SII, SIRI and PNI in the prognosis of AFP- producing GC (AFPGC). Besides, this study would also compare the differences in tumor immune microenvironment, clinical characteristics and prognosis between AFPGC and AFP- GC patients to improve the understanding of this disease.

METHODS

573 patients enrolled were retrospectively studied. They were divided into AFP+ group (AFP ≥ 20 ng/mL) and AFP- group (AFP < 20 ng/mL), comparing the levels of NLR/PLR/MLR/SII/SIRI/PNI and prognosis. In AFP+ group, the impact of NLR/PLR/MLR/SII/SIRI/PNI and their dynamic changes on prognosis were further explored.

RESULTS

Compared with AFP- patients, AFP+ patients had higher NLR/PLR/MLR/SII/SIRI and lower PNI levels and poorer overall survival (OS). In the AFP+ group, mortality was significantly lower in the lower NLR/PLR/MLR/SII/SIRI group and higher PNI group. Moreover, the dynamic increase (NLR/PLR/MLR/SII/SIRI) or decrease (PNI) was associated with the rise of mortality within 1 year of follow-up.

CONCLUSION

Compared with AFP- patients, the level of inflammation-related peripheral blood markers significantly increased in AFP+ patients, which was correlated with OS of AFP+ patients. Also, the gradual increase of SII and SIRI was associated with the risk of death within one year in AFP+ patients. AFPGC should be considered as a separate type and distinguished from AFP- GC because of the difference in tumor immune microenvironment. It requires basic experiments and large clinical samples in the future.

Pre- and Post-treatment Double-Sequential-Point Dynamic Radiomic Model in the Response Prediction of Gastric Cancer to Neoadjuvant Chemotherapy: 3-Year Survival Analysis

BACKGROUND

Prognosis prediction of patients with gastric cancer after neoadjuvant chemotherapy is suboptimal. This study aims to develop and validate a dynamic radiomic model for prognosis prediction of patients with gastric cancer on the basis of baseline and posttreatment features.

PATIENTS AND METHODS

This single-center cohort study included patients with gastric adenocarcinoma treated with neoadjuvant chemotherapy from June 2009 to July 2015 in the Gastrointestinal Cancer Center of Peking University Cancer Hospital. Their clinicopathological data, pre-treatment and post-treatment computed tomography (CT) images, and pathological reports were retrieved and analyzed. Four prediction models were developed and validated using tenfold cross-validation, with death within 3 years as the outcome. Model discrimination was compared by the area under the curve (AUC). The final radiomic model was evaluated for calibration and clinical utility using Hosmer-Lemeshow tests and decision curve analysis.

RESULTS

The study included 205 patients with gastric adenocarcinoma [166 (81%) male; mean age 59.9 (SD 10.3) years], with 71 (34.6%) deaths occurring within 3 years. The radiomic model alone demonstrated better discrimination than the pathological T stage (ypT) stage model alone (cross-validated AUC 0.598 versus 0.516, P = 0.009). The final radiomic model, which incorporated both radiomic and clinicopathological characteristics, had a significantly higher cross-validated AUC (0.769) than the ypT stage model (0.516), the radiomics alone model (0.598), and the ypT plus other clinicopathological characteristics model (0.738; all P < 0.05). Decision curve analysis confirmed the clinical utility of the final radiomic model.

CONCLUSIONS

The developed radiomic model had good accuracy and could be used as a decision aid tool in clinical practice to differentiate prognosis of patients with gastric cancer.

Study on the diagnostic value of MDCT extramural vascular invasion in preoperative N staging of gastric cancer patients

BACKGROUND

To explore the diagnostic value of multidetector computed tomography (MDCT) extramural vascular invasion (EMVI) in preoperative N Staging of gastric cancer patients.

METHODS

According to the MR-defined EMVI scoring standard of rectal cancer, we developed a 5-point scale scoring system to evaluate the status of CT-detected extramural vascular invasion(ctEMVI), 0-2 points were ctEMVI-negative status, and 3-4 points were positive status for ctEMVI. Patients were divided into ctEMVI positive group and ctEMVI negative group. The correlation between ctEMVI and clinical features was analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of ctEMVI for pathological metastatic lymph nodes and N staging, The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of pathological N staging using ctEMVI and short-axis diameter were generated and compared.

RESULTS

The occurrence rate of lymphovascular invasion (LVI) and proportion of tumors with a greatest diameter > 6 cm in the ctEMVI positive group was higher than that in the ctEMVI negative group (P < 0.05). Spearman correlation analysis showed a positive correlation between ctEMVI and LVI, N stage, and tumor size (P < 0.05). For ctEMVI scores ≥ 3,The AUC of ctEMVI for diagnosing lymph node metastasis, N stage ≥ N2, and N3 stage were 0.857, 0.802, and 0.758, respectively. The sensitivity, NPV and accuracy of ctEMVI for diagnosing N stage ≥ N2 were superior to those of short-axis diameter (P < 0.05), while sensitivity, specificity, PPV, NPV, and accuracy of ctEMVI for diagnosing N3 stage were superior to those of short-axis diameter (P < 0.05).

CONCLUSION

ctEMVI has important value in diagnosing metastatic lymph nodes and advanced N staging. As an important imaging marker, ctEMVI can be included in the preoperative imaging evaluation of patients, providing important assistance for clinical guidance and treatment.

A bibliometric analysis of gastric cancer liver metastases: advances in mechanisms of occurrence and treatment options

BACKGROUND

Gastric cancer (GC) is the fifth most commonly diagnosed cancer worldwide, and its poor prognosis is predominantly attributed to distant metastasis. Liver is the primary site of GC metastasis. However, there is no universally approved treatment regimen for liver metastasis in GC. The aim of this article is to review the current research status and trends of liver metastasis of gastric cancer worldwide.

METHODS

We utilized the Web of Science Core Collection database to identify articles on liver metastasis from GC published between 2000 and 2022. We used bibliometric methods to analyze authors, institutions, countries, journals, and references through CiteSpace and VOSviewer. A total of 1,003 articles were included in this study.

RESULTS

Japan published the most articles in the field, followed by China. Nagoya University is the leading institution in the field of liver metastases in GC. Yasuhiro Kodera from Japan has made significant achievements in this area. We identified Gastric Cancer to be the most influential journal in this field. Using cluster analysis, the keywords were divided into four major clusters:(1) the molecular mechanism of gastric cancer liver metastasis (2) prognosis (3) liver resection (4) chemotherapy.

CONCLUSION

Our study systematically summarizes the results of gastric cancer liver metastasis research from 2000 to 2022 and describes and predicts research hotspots and trends on a global scale. Research on the molecular mechanisms of gastric cancer liver metastasis will become a hot topic in the future, and the expansion of the surgical treatment scope and the advancement of translational therapy will benefit more patients.

Predicting the prognosis of operable gastric cancer patients by dynamic changes in platelets before and after surgery: a retrospective cohort study

PURPOSE

Since the relationship between postoperative platelet count and prognosis is still unclear, we designed a standardized index of platelet count to predict the prognosis of gastric cancer (GC).

METHODS

We designed a development validation cohort for the pre/post platelet ratio. We determined the ability of PPR to predict mortality in gastric cancer patients and validated them by a separate cohort. Survival was assessed by Kaplan-Meier analysis and associations explored by multivariate and multivariate analyses. The usefulness of the prediction was estimated by measuring the time-dependent ROC. Decision-curve analysis was used to validate the net clinical benefit.

RESULTS

The sample distribution was similar in the two cohorts, and the 1-, 3-, and 5-year OS evaluation of the postoperative/preoperative platelet ratio was the largest for AUC in the two cohorts. Meanwhile, PPR has a good predictive value and a net clinical benefit.

CONCLUSIONS

PPR has been identified and validated to be independently concerned about OS of patients with GC and was a reliable and economic indicator to evaluate the prognosis.

Clinical Significance of Fibrinogen and Platelet to Pre-Albumin Ratio in Predicting the Prognosis of Advanced Gastric Cancer

OBJECTIVE

The aim of this study was to investigate the clinical significance of Fibrinogen and Platelet to Pre-albumin Ratio(FPAR) in predicting the prognosis of patients with advanced gastric cancer(AGC) and to construct a predictive model.

METHODS

We collected clinical data from 489 postoperative patients with AGC. FPAR was divided into high and low groups according to the receiver operating characteristic (ROC) curve. The value of FPAR in predicting the prognosis of progressive gastric cancer was analysed using univariate and multivariable Cox regression analysis and its relationship with clinicopathological features. Finally, the Overall Survival(OS) and recurrence-free survival(RFS) prediction models were constructed and validated using FPAR.

RESULTS

Univariate and multifactorial cox regression analysis showed that grade (P<0.001), TNM-stage (P<0.001), chemotherapy (P<0.001), and FPAR (OR=3.054,95% CI:2.088-4.467, P<0.001) were independent risk factors for OS; grade (P=0.021), N-stage (P=0.024), TNM-stage (P=0.033), and FPAR (OR=2.215,95% CI:1.634-3.003, P<0.001) were independent risk factors for RFS. Subgroup analysis showed that the FPAR-low group had higher OS and RFS than the FPAR-high group, regardless of the patient's TNM stage (p<0.05). However, OS was instead higher in the the stage III-FPAR-low group than in the the stage II-FPAR-high group (p<0.05), while RFS was not significantly different. Predictive models incorporating FPAR had better predictive performance than those without FPAR, showing wide range of net benefit and AUC. After correction, the 2-year AUC, 3-year AUC and C-index of the OS model were 0.737, 0.756, and 0.746; the 2-year AUC, 3-year AUC, and C-index of the RFS model were 0.738, 0.758, and 0.711.

CONCLUSION

FPAR levels were associated with prognosis in patients with AGC and could independently predict RFS and OS.

Gastric hydrodistension CT versus CT without gastric distension in preoperative TN staging of gastric carcinoma: analysis of single-center cancer registry

Accurate staging of gastric cancer is essential for the selection and optimization of therapy. Hydrodistension of the stomach is recommended to improve the accuracy of preoperative staging with contrast-enhanced multidetector computed tomography (MDCT). This study compares the performance of contrast-enhanced gastric water distension versus a nondistension MDCT protocol for T and N staging and serosal invasion in comparison to surgical histopathology. After propensity score matching, 86 patients in each group were included for analysis. The overall accuracy of distension versus nondistension group in T staging was 45% (95% CI 35-56) and 55% (95% CI 44-65), respectively (p = 0.29). There was no difference in the sensitivity and specificity in individual T staging and assessment of serosal invasion (all p > 0.41). Individual stage concordance with pathology was not significantly different (all p > 0.41). The overall accuracy of N staging was the same for distension and nondistension groups (51% [95% CI 40-62]). The majority of N0 staging (78-81%) were correctly staged, whereas N3 staging cases (63-68%) were predominantly understaged. In summary, there was no significant difference in the diagnostic performance of individual TN staging and assessment of serosal invasion using MDCT with or without gastric water distension.

Proteasome Subunit Alpha Type 7 Promotes Proliferation and Metastasis of Gastric Cancer Through MAPK Signaling Pathway

BACKGROUND

Proteasome subunit alpha type 7 (PSMA7) shows a carcinogenic effect on various human malignancies, but its role and regulatory mechanism in gastric carcinoma (GC) remain unclear.

AIMS

This study aimed to explore the role and mechanism of PSMA7 in GC.

METHODS

In this study, PSMA7 expressions in GC cells and tissues were detected, and relationships between PSMA7 and clinicopathological features were explored. Then, PSMA7 levels in human GC cells were intervened, and changes in cell biological behavior were observed in vitro and vivo. Key proteins and downstream factors of MAPK signaling pathway were detected after PSMA7 intervention.

RESULTS

PSMA7 was upregulated in GC tissues and cell lines. PSMA7 overexpression was significantly associated with poor pTNM, cTNM stage, and high HP infection. PSMA7 can promote proliferation, invasion, and metastasis of GC cells in vitro and vivo. Furthermore, PSMA7 expression affected the phosphorylation level of JNK, P38, ERK and the expressions of their downstream factors Ap-1, c-myc, P53.

CONCLUSION

PSMA7 can promote GC proliferation, invasion, and metastasis through MAPK signaling pathway in GC cells.

Development and validation of a nomogram for primary duodenal carcinoma: a multicenter, population-based study

Aim: This study aimed to develop a predictive model for patients with duodenal carcinoma. Methods: Duodenal carcinoma patients from the Surveillance, Epidemiology, and End Results database (2010-2015) and the First Affiliated Hospital of Nanchang University (2010-2021) were enrolled. A nomogram was constructed according to least absolute shrinkage and selection operator regression analysis, the Akaike information criterion approach and Cox regression analysis. Results: Five independent prognostic factors were significantly associated with the prognosis of the duodenal carcinoma patients. A nomogram was constructed with a C-index in the training and validation cohorts of 0.671 (95% CI: 0.578-0.716) and 0.662 (95% CI: 0.529-0.773), respectively. Conclusion: The established nomogram model provided visualization of the risk of each prognostic factor.

Gastric Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology

Gastric cancer is the third leading cause of cancer-related deaths worldwide. Over 95% of gastric cancers are adenocarcinomas, which are typically classified based on anatomic location and histologic type. Gastric cancer generally carries a poor prognosis because it is often diagnosed at an advanced stage. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability (MSI) status, and the expression of programmed death-ligand 1 (PD-L1), has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with localized gastric cancer. This selection from the NCCN Guidelines for Gastric Cancer focuses on the management of unresectable locally advanced, recurrent, or metastatic disease.

Triplet versus doublet neoadjuvant chemotherapy regimens for locally advanced gastric cancer: a propensity score matching analysis

BACKGROUND

To investigate the differences between doublet and triplet neoadjuvant chemotherapy (NAC) regimens in efficacy and safety profile.

METHODS

A total of 227 locally advanced gastric cancer (LAGC) patients who received NAC and sequential radical gastrectomy were reviewed. After propensity score matching (PSM), 140 patients with similar baseline characteristics were selected. Among them, 70 received doublet NAC regimens consisted of platinum and fluorouracil; the other 70 received triplet NAC regimens consisted of docetaxel, platinum, and fluorouracil.

RESULTS

The efficacy of doublet and triplet regimens was comparable after propensity score matching in terms of tumor regression (pathological complete response, Doublet 11.4% vs. Triplet 15.7%, p = 0.642), achieving of R0 resection (Doublet 88.6% vs. Triplet 88.6%, p = 1), 1-year disease-free survival (DFS) (Doublet 77.1% vs. Triplet 68.6%, p = 0.178), 3-years overall survival (OS) (Doublet 54.3% vs. Triplet 60.9%, p = 0.941). Post-surgery complications were more common in the triplet cohort (Doublet 5.7% vs. Triplet 27.1%, p = 0.001), especially abdominal infection (Doublet 0% vs. Triplet 11.1%, p = 0.001).

CONCLUSIONS

A more intense preoperative triplet NAC regimen does not bring extra downstage effect and survival benefit compared to a doublet regimen. It may even result in a higher risk of post-surgery complications.

Development and validation of pretreatment nomogram for disease-specific mortality in gastric cancer-A competing risk analysis

Background

In several reports, gastric cancer nomograms for predicting overall or disease‐specific survival have been described. The American Joint Committee on Cancer (AJCC) introduced the attractiveness of disease‐specific mortality (DSM) as an endpoint of risk model. This study aimed to develop the first pretreatment gastric cancer nomogram for predicting DSM that considers competing risks (CRs).

Methods

The prediction model was developed using data for 5231 gastric cancer patients. Fifteen prognosticators, which were registered at diagnosis, were evaluated. The nomogram for DSM was created as visualizations of the multivariable Fine and Gray regression model. An independent cohort for external validation consisted of 389 gastric cancer patients from a different institution. The performance of the model was assessed by discrimination (Harrell's concordance (C)‐index), calibration, and decision curve analysis. DSM and CRs were evaluated, paying special attention to host‐related factors such as age and Eastern Cooperative Oncology Group performance status (ECOG PS), by using Gray's univariable method.

Results

Fourteen prognostic factors were selected to develop the nomogram. The new nomogram for DSM exhibited good discrimination. Its C‐index of 0.887 surpassed that of the American Joint Committee on Cancer (AJCC) clinical staging (0.794). The C‐index was 0.713 (AJCC, 0.582) for the external validation cohort. The nomogram showed good performance internally and externally, in the calibration and decision curve analysis. Host‐related factors including age and ECOG PS, were strongly correlated with competing risks.

Conclusions

The newly developed nomogram accurately predicts DSM, which can be used for patient counseling in clinical practice.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Current status and future perspectives on neoadjuvant therapy in gastric cancer

Gastric cancer, with high morbidity and mortality rates, is one of the most heterogeneous tumors. Radical gastrectomy and postoperative chemotherapy are the standard treatments. However, the safety and efficacy of neoadjuvant therapy (NAT) need to be confirmed by many trials before implementation, creating a bottleneck in development. Although clinical benefits of NAT have been observed, a series of problems remain to be solved. Before therapy, more contributing factors should be offered for choice in the intended population and ideal regimens. Enhanced computed tomography (CT) scanning is usually applied to evaluate effectiveness according to Response Evaluation Criteria in Solid Tumors (RECIST), yet CT scanning results sometimes differ from pathological responses. After NAT, the appropriate time for surgery is still empirically defined. Our review aims to discuss the abovementioned issues regarding NAT for GC, including indications, selection of regimens, lesion assessment and NAT-surgery interval time.

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.

Potential Value of Radiomics in the Identification of Stage T3 and T4a Esophagogastric Junction Adenocarcinoma Based on Contrast-Enhanced CT Images

Purpose

This study was designed to evaluate the predictive performance of contrast-enhanced CT-based radiomic features for the personalized, differential diagnosis of esophagogastric junction (EGJ) adenocarcinoma at stages T3 and T4a.

Methods

Two hundred patients with T3 (n = 44) and T4a (n = 156) EGJ adenocarcinoma lesions were enrolled in this study. Traditional computed tomography (CT) features were obtained from contrast-enhanced CT images, and the traditional model was constructed using a multivariate logistic regression analysis. A radiomic model was established based on radiomic features from venous CT images, and the radiomic score (Radscore) of each patient was calculated. A combined nomogram diagnostic model was constructed based on Radscores and traditional features. The diagnostic performances of these three models (traditional model, radiomic model, and nomogram) were assessed with receiver operating characteristics curves. Sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and areas under the curve (AUC) of models were calculated, and the performances of the models were evaluated and compared. Finally, the clinical effectiveness of the three models was evaluated by conducting a decision curve analysis (DCA).

Results

An eleven-feature combined radiomic signature and two traditional CT features were constructed as the radiomic and traditional feature models, respectively. The Radscore was significantly different between patients with stage T3 and T4a EGJ adenocarcinoma. The combined nomogram performed the best and has potential clinical usefulness.

Conclusions

The developed combined nomogram might be useful in differentiating T3 and T4a stages of EGJ adenocarcinoma and may facilitate the decision-making process for the treatment of T3 and T4a EGJ adenocarcinoma.

The Epigenetic landscape of Circulating tumour cells

Cancer metastasis is the main reason for the high mortality in patients, contributing to 90% of cancer-related deaths. Biomarkers for early detection and therapeutic monitoring are essential to improve cancer outcomes. Circulating tumour cells (CTCs) arise from solid tumours and are capable of metastatic dissemination via the bloodstream or lymphatic system. Thus, CTCs can potentially be developed as a minimally invasive biomarker for early detection and therapeutic monitoring. Despite its clinical potential, research on CTCs remains limited, and this is likely due to their low numbers, short half-life, and the lack of robust methods for their isolation. There is also a need for molecular characterisation of CTCs to identify tumour-specific features, such as epigenetic signatures of metastasis. This review provides an overview of the epigenetic landscape of CTCs. We discuss the role of epigenetic modifications in CTC dissemination,metastatic tumour formation and progression and highlight its clinical implications.

Proposed Modification of the 8th Edition of the AJCC Staging System for Gastric Cancer

Background: The American Joint Committee on Cancer (AJCC) staging system has been the standardized staging system for malignancies since the first edition in 1987. The 8th edition of gastric cancer was released in 2016, and is expected to be used in clinical practice in 2018. The aim of this study was to improve this new gastric cancer staging system. Methods: We conducted median overall survival analyses in a cohort of 8359 gastric cancer patients from the Surveillance, Epidemiology, and End Results (SEER) database (2004-2014) via Kaplan-Meier curves and log-rank tests, and proposed a modified staging system based on median OS. The concordance index (C-index) was conducted to evaluate the predictive accuracy. Results: Using the 8th AJCC staging system, the median OS of patients at the same stage varied widely between the different substages, especially in stage III. Despite the definitions of T, N, and M, substages in the modified staging system were regrouped based on median OS. The C-index of stage III patients with the modified staging system [0.579, 95% confidence interval (CI) 0.564-0.593] was higher than the 8th AJCC staging system (0.567, 95% CI 0.552-0.581). Moreover, we divided these patients into two groups according to their examined lymph node counts (≥15 or 1-14), and studied the effectiveness of the modified staging system in the two groups. Conclusions: The modified 8th AJCC staging system for gastric cancer proposed in this study generates better prognostic stratifications and may be evaluated for further update. Abbreviations:AJCCAmerican Joint Committee on CancerOSOverall SurvivalSEERSurveillance, Epidemiology, and End Results.

MicroRNA-454-3p inhibits cell proliferation and invasion in esophageal cancer by targeting insulin-like growth factor 2 mRNA-binding protein 1

Esophageal cancer (ESCA) is the eighth most common cause of cancer-associated mortality in humans. An increasing number of studies have demonstrated that microRNAs (miRs) serve important roles in mediating tumor initiation and progression. miR-454-3p has been found to be involved in the development of various human malignancies; however, little is known about the role of miR-454-3p in esophageal cancer. In the present study, the protein and gene expression levels of miR-454-3p in ESCA tissues and cells were downregulated compared with adjacent normal tissues and normal human esophageal epithelial cells. Additionally, miR-454-3p downregulation resulted in improved survival rates in patients with ESCA, and miR-454-3p overexpression significantly suppressed cell proliferation, migration and invasion and promoted apoptosis in four ESCA cell lines (EC9706, ECA109, TE-1 and TE-8). It was found that miR-454-3p overexpression inhibited the expression of insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) at the protein and mRNA expression levels. Furthermore, it was demonstrated that miR-454-3p inhibited ESCA cell proliferation, migration and apoptosis by targeting IGF2BP1 via the ERK and AKT signaling pathways in a subcutaneous xenograft tumor mouse model. These results showed that miR-454-3p functioned as an important tumor suppressor in ESCA by targeting IGFBP1. Therefore, miR-454-3p may be a novel prognostic biomarker and therapeutic target for patients with ESCA.

Modification of Mcl-1 alternative splicing induces apoptosis and suppresses tumor proliferation in gastric cancer

Splicing dysregulation, which leads to apoptosis resistance, has been recognized as a major hallmark for tumorigenesis and cancer progression. Targeting alternative splicing by either increasing pro-apoptotic proteins or inhibiting anti-apoptotic proteins in tumor cells may be an effective approach for gastric cancer (GC) therapy. However, the role of modulation of alternative splicing in GC remains poorly understood. In this study, to the best of our knowledge, the unbalanced expression of the myeloid cell leukemia-1 (Mcl-1) splicing variants, Mcl-1L and Mcl-1S, was identified in GC patients for the first time. Increasing anti-apoptotic Mcl-1L and decreasing pro-apoptotic Mcl-1S expression levels were correlated with tumor proliferation and poor survival. In vitro data showed that a shift in splicing from Mcl-1L to Mcl-1S induced by treatment with Mcl-1-specific steric-blocking oligonucleotides (SBOs) efficiently decreased Mcl-1L expression, increased Mcl-1S expression, and accelerated tumor cell apoptosis in a dose-dependent manner. Additionally, mouse xenotransplant models confirmed that modification of Mcl-1 alternative splicing increased tumor cell death and suppressed tumor proliferation. This study demonstrated that the modification of Mcl-1 splicing might stimulate the pro-apoptotic factor and inhibit the anti-apoptotic protein to induce significant apoptosis. Thus, this finding provided a strategy for cancer therapy, according to which SBOs could be used to change the Mcl-1 splicing pattern, thereby inducing apoptosis.

Current status of proximal gastrectomy for gastric and esophagogastric junctional cancer: A review

Proximal gastrectomy (PG) is one of the function-preserving surgical methods for the treatment of upper gastric cancer. Favorable postoperative results have been reported in comparison with total gastrectomy. However, because there are challenges, such as postoperative reflux esophagitis, anastomotic stenosis, and residual food, appropriate selection of a reconstruction method is crucial. Some methods include esophagogastric anastomosis, including simple esophagogastrostomy, tube-like stomach esophagogastrostomy, side overlap with fundoplication by Yamashita, and double-flap technique, and reconstruction using the small intestine, including double-tract methods, jejunal interposition, and jejunal pouch interposition. However, standard reconstruction methods are yet to be established. PG has also been employed in early gastric cancer of the upper third of the stomach, and indications have also been extended to esophagogastric junction cancer, which has shown an increase in recent years. Although many retrospective studies have revealed the functional benefits or oncological safety of PG, the characteristics of each surgical procedure should be understood so that an appropriate reconstruction method, with a reflux prevention mechanism and minimal postoperative injury, can be selected.

Preoperative computed tomography-guided disease-free survival prediction in gastric cancer: a multicenter radiomics study

PURPOSE

Preoperative and noninvasive prognosis evaluation remains challenging for gastric cancer. Novel preoperative prognostic biomarkers should be investigated. This study aimed to develop multidetector-row computed tomography (MDCT)-guided prognostic models to direct follow-up strategy and improve prognosis.

METHODS

A retrospective dataset of 353 gastric cancer patients were enrolled from two centers and allocated to three cohorts: training cohort (n = 166), internal validation cohort (n = 83), and external validation cohort (n = 104). Quantitative radiomic features were extracted from MDCT images. The least absolute shrinkage and selection operator penalized Cox regression was adopted to construct a radiomic signature. A radiomic nomogram was established by integrating the radiomic signature and significant clinical risk factors. We also built a preoperative tumor-node-metastasis staging model for comparison. All models were evaluated considering the abilities of risk stratification, discrimination, calibration, and clinical use.

RESULTS

In the two validation cohorts, the established four-feature radiomic signature showed robust risk stratification power (P = 0.0260 and 0.0003, log-rank test). The radiomic nomogram incorporated radiomic signature, extramural vessel invasion, clinical T stage, and clinical N stage, outperforming all the other models (concordance index = 0.720 and 0.727) with good calibration and decision benefits. Also, the 2-yr disease-free survival (DFS) prediction was most effective (time-dependent area under curve = 0.771 and 0.765). Moreover, subgroup analysis indicated that the radiomic signature was more sensitive in risk stratifying patients with advanced clinical T/N stage.

CONCLUSIONS

The proposed MDCT-guided radiomic signature was verified as a prognostic factor for gastric cancer. The radiomic nomogram was a noninvasive auxiliary model for preoperative individualized DFS prediction, holding potential in promoting treatment strategy and clinical prognosis.

Development and validation of a pretreatment nomogram to predict overall survival in gastric cancer

Background

Pretreatment clinical staging is essential to select therapy. However, there have been no published pretreatment gastric cancer nomograms constructed using pretreatment clinical prognostic factors, including in nonresection patients. We aimed to develop a new pretreatment gastric cancer nomogram for individualized prediction of overall survival (OS).

Methods

The nomogram was developed using data of 5231 Japanese gastric cancer patients, and it was created with a Cox regression model. Fifteen clinical variables, which were obtained at pretreatment, were collected and registered. Data of two independent cohorts of patients from Seoul St. Mary's Hospital (1001 patients), and the University of Verona (389 patients) formed the external validation cohorts. The model was validated internally and externally using measures of discrimination (Harrell's C‐index), calibration, and decision curve analysis.

Results

The developed nomogram showed good discrimination, with a C‐index of 0.855; that of the American Joint Committee on Cancer (AJCC) clinical stage was 0.819. In the external validation procedure, the C‐indexes were 0.856 (AJCC, 0.795) in the Seoul St. Mary's cohort and 0.714 (AJCC, 0.648) in the University of Verona cohort. The nomogram performed well in the calibration and decision curve analyses when applied to both the internal and external validation cohorts. A stage‐specific subset survival analysis of the three risk groups calculated using the nomogram also showed the superiority of nomogram‐prediction when compared to AJCC.

Conclusion

This new pretreatment model accurately predicts OS in gastric cancer and can be used for patient counseling in clinical practice and stratification in clinical trials.

Preoperative Systemic Immune-Inflammation Index (SII) for Predicting the Survival of Patients with Stage I-III Gastric Cancer with a Signet-Ring Cell (SRC) Component

Background

Recently, a novel systemic immune-inflammation index (SII) based on peripheral lymphocytes, neutrophils, and platelets has been reported to be correlated with patient prognosis in several malignancies, including gastric cancer. However, the prognostic value of the SII for gastric cancer patients with a signet-ring cell (SRC) component has not yet been reported. In this study, we aimed to assess the prognostic value of the SII in gastric cancer patients with an SRC component after curative resection.

Methods

This study was a retrospective analysis of 512 GC patients with an SRC component who underwent curative resection. The prognostic value of the SII was analyzed by the Kaplan-Meier method and Cox proportional hazards regression model.

Results

In our study cohort, an optimal cut-off value for the SII of 527 was used to stratify patients with gastric cancer (GC) into low (<527) and high SII (≥527) groups. Our study indicated that a high SII (≥527) was significantly correlated with a large tumor size (p < 0.001), infiltration of serosa (p < 0.001), lymph node metastasis (p < 0.001), and advanced TNM stage (p < 0.001). Univariate and multivariate analyses further demonstrated that a low SII was correlated with better clinical outcome and was an independent prognostic predictor in GC patients with an SRC component. Furthermore, the SII retained prognostic value in the subgroup analysis, including subgroup of different TNM stages and pure or mixed signet-ring cell carcinomas (SRCCs).

Conclusion

The SII is a simple, promising, and practical prognostic biomarker for patients with surgically resected mixed SRCC and pure SRCC. The SII could complement current prognostic tools for better treatment planning and stratification of patients.

The relationship between the number of examined lymph nodes and the efficacy of chemotherapy for gastric cancer

BACKGROUND

The purpose of this research was to investigate the relationship between the number of examined lymph nodes (eLNs) and the prognosis.

METHODS

A retrospective examination of reports and studies carried out at two institutions was conducted. According to TNM stages, the relationship between the number of eLNs and the prognosis was analyzed.

RESULTS

The 5-year disease-specific survival (DSS) of all enrolled patients was 66.3%. A multivariate analysis showed the type of gastrectomy, histologic type, perineural invasion, pT stage, pN stage, chemotherapy and eLNs to be independent prognostic markers. Additionally, with the exception of patients with stage I disease, the 5-year DSS of patients who had < 25 eLNs removed had a higher risk of having a worst prognosis compared to patients who had ≥ 25 eLNs removed. Through this study, a hypothetical TNM staging system was obtained for predicting the prognosis according to the number of eLNs. Chemotherapy was able to improve the prognosis of patients with stage III and < 25 eLNs in stage II.

CONCLUSIONS

Extended lymphadenectomy with a new goal of dissecting 25 LNs for the evaluation of stage II-III cancer cases is recommended. Our hypothetical TNM staging system may be able to stratify the risk more accurately compared to the current AJCC 8th system. Chemotherapy can improve the prognosis in advanced gastric cancer, but its benefit may be affected by the surgical quality.

Survival outcomes after laparoscopy-assisted distal gastrectomy versus open distal gastrectomy with nodal dissection for clinical stage IA or IB gastric cancer (JCOG0912): a multicentre, non-inferiority, phase 3 randomised controlled trial

BACKGROUND

Laparoscopy-assisted distal gastrectomy (LADG) is increasingly being used as an alternative to open distal gastrectomy (ODG) for gastric cancer treatment. Retrospective studies have shown equivalent survival with the two procedures, but these studies are limited by selection bias because LADG is more technically difficult than ODG. We aimed to evaluate whether LADG was non-inferior to ODG in terms of long-term survival outcomes.

METHODS

We did an open-label, multicentre, non-inferiority, phase 3 randomised controlled trial at 33 institutions in Japan. Patients aged 20-80 years with histologically confirmed gastric adenocarcinoma (T1N0, T1N1, or T2[MP]N0), clinical stage I, in the middle or lower third of the stomach, Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, with a body-mass index of less than 30 kg/m², were randomly assigned (1:1) to receive ODG or LADG. Randomisation was done by telephone, fax, or with a web-based system in the Japan Clinical Oncology Group Data Center; a minimisation method with a random component was used to adjust for institution and clinical stage (IA or IB). Only study-accredited surgeons performed ODG and LADG. The primary endpoint was relapse-free survival and was analysed according to the intention-to-treat principle. The non-inferiority margin (LADG vs ODG) was set at a hazard ratio (HR) of 1·54. The trial was registered with the UMIN Clinical Trials Registry, UMIN000003319.

FINDINGS

Between March 15, 2010, and Nov 29, 2013, 921 patients were enrolled and randomly assigned to receive ODG (n=459) or LADG (n=462). 912 (99%) participants had the assigned surgery. 5-year relapse-free survival was 94·0% (95% CI 91·4-95·9) in the ODG group and 95·1% (92·7-96·8) in the LADG group. LADG was non-inferior to ODG for relapse-free survival (HR 0·84 [90% CI 0·56-1·27]), p=0·0075). The most common grade 3 or 4 adverse event was bowel obstruction, occurring in 11 (2%) of 455 patients in the ODG group and five (1%) of 457 patients in the LADG group. There were no treatment-related deaths.

INTERPRETATION

This trial supports the non-inferiority of LADG compared with ODG for clinical stage I gastric cancer relapse-free survival, suggesting that LADG should be considered a standard treatment option when performed by experienced surgeons.

FUNDING

Japan National Cancer Center, Ministry of Health, Labour and Welfare of Japan, Japan Agency for Medical Research and Development.

Effect of Laparoscopic vs Open Distal Gastrectomy on 3-Year Disease-Free Survival in Patients With Locally Advanced Gastric Cancer: The CLASS-01 Randomized Clinical Trial

IMPORTANCE

Laparoscopic distal gastrectomy is accepted as a more effective approach to conventional open distal gastrectomy for early-stage gastric cancer. However, efficacy for locally advanced gastric cancer remains uncertain.

OBJECTIVE

To compare 3-year disease-free survival for patients with locally advanced gastric cancer after laparoscopic distal gastrectomy or open distal gastrectomy.

DESIGN, SETTING, AND PATIENTS

The study was a noninferiority, open-label, randomized clinical trial at 14 centers in China. A total of 1056 eligible patients with clinical stage T2, T3, or T4a gastric cancer without bulky nodes or distant metastases were enrolled from September 2012 to December 2014. Final follow-up was on December 31, 2017.

INTERVENTIONS

Participants were randomized in a 1:1 ratio after stratification by site, age, cancer stage, and histology to undergo either laparoscopic distal gastrectomy (n = 528) or open distal gastrectomy (n = 528) with D2 lymphadenectomy.

MAIN OUTCOMES AND MEASURES

The primary end point was 3-year disease-free survival with a noninferiority margin of -10% to compare laparoscopic distal gastrectomy with open distal gastrectomy. Secondary end points of 3-year overall survival and recurrence patterns were tested for superiority.

RESULTS

Among 1056 patients, 1039 (98.4%; mean age, 56.2 years; 313 [30.1%] women) had surgery (laparoscopic distal gastrectomy [n=519] vs open distal gastrectomy [n=520]), and 999 (94.6%) completed the study. Three-year disease-free survival rate was 76.5% in the laparoscopic distal gastrectomy group and 77.8% in the open distal gastrectomy group, absolute difference of -1.3% and a 1-sided 97.5% CI of -6.5% to ∞, not crossing the prespecified noninferiority margin. Three-year overall survival rate (laparoscopic distal gastrectomy vs open distal gastrectomy: 83.1% vs 85.2%; adjusted hazard ratio, 1.19; 95% CI, 0.87 to 1.64; P = .28) and cumulative incidence of recurrence over the 3-year period (laparoscopic distal gastrectomy vs open distal gastrectomy: 18.8% vs 16.5%; subhazard ratio, 1.15; 95% CI, 0.86 to 1.54; P = .35) did not significantly differ between laparoscopic distal gastrectomy and open distal gastrectomy groups.

CONCLUSIONS AND RELEVANCE

Among patients with a preoperative clinical stage indicating locally advanced gastric cancer, laparoscopic distal gastrectomy, compared with open distal gastrectomy, did not result in inferior disease-free survival at 3 years.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01609309.

Different prognostic implication of ypTNM stage and pTNM stage for gastric cancer: a propensity score-matched analysis

Background

Pathological stage is considered as the best prognosis indicator for gastric cancer. With the increasing use of neoadjuvant chemotherapy (NACT), the latest TNM staging included a new pathological stage of ypTNM for patients with NACT. However, no study has investigated if ypTNM stage has the same prognostic implication as pTNM stage for gastric cancer.

Methods

We retrospectively selected eligible patients within a prospectively maintained database containing all patients treated with gastric cancer in Peking University Cancer Hospital from 2007 to 2015 using overall survival as the outcome. Patients using ypTNM and pTNM were 1:1 matched by propensity scores (PS) calculated from a model containing variables associated with ypTNM use or survival. Overall survival was compared by unconditional Cox regression. Conventional multivariate analysis was conducted to corroborate PS matching results.

Results

1441 patients were included in the analysis with a median follow-up of 37 months (range = 2–106). The matched sample contained 756 patients. After PS matching, patients with specific ypTNM stage were 1.34 (95%CI = 1.05–1.72, P = 0.019) times more likely to die than patients with the same pTNM stage. Similar to the results of PS matching, multivariate Cox regression yielded a hazard ratio (HR) of 1.35 (95%CI = 1.09–1.67, P = 0.006). Subgroup analysis indicated this survival difference between ypTNM and pTNM stage varied by the specific TNM stage of patients. The HR was 3.44 (95%CI = 1.06–11.18, P = 0.040) and 1.28 (95%CI = 1.00–1.62, P = 0.048) for patients in stage I and III, respectively; whereas for stage II patients, no significant difference was observed (HR = 1.37, 95%CI = 0.78–2.38, P = 0.27).

Conclusion

Gastric cancer patients with specific ypTNM stage had worse prognosis compared to those at the same stage defined by pTNM.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5283-3) contains supplementary material, which is available to authorized users.