Response to neoadjuvant chemotherapy best predicts survival after curative resection of gastric cancer

NESC Multicenter Phase II Trial in the Preoperative Treatment of Gastric Adenocarcinoma with Chemotherapy (Docetaxel-Cisplatin-5FU+Lenograstim) Followed by Chemoradiation Based 5FU and Oxaliplatin and Surgery

PURPOSE

Preoperative chemoradiation (CRT) is expected to increase the rate of curative resection and complete histological response. In this trial, we investigated the efficacy of a neoadjuvant CRT regimen in gastric adenocarcinoma (NCT01565109 trial).

MATERIALS AND METHODS

Patients with stage IB to IIIC gastric adenocarcinoma, endoscopy ultrasound and computed tomography-scan diagnosed, were eligible for this phase II trial. Neoadjuvant treatment consisted of 2 cycles of chemotherapy with DCF (docetaxel, cisplatin, and 5-fluorouracil [5FU]) followed by preoperative CRT with oxaliplatin, continuous 5FU and radiotherapy (45 Gy in 25 fractions of 1.8 Gy, 5 fractions per week for 5 weeks) administered before surgery. R0-resection rate, pathological complete response (pathCR) rate, and survival (progression-free survival [PFS] and overall survival [OS]) were evaluated as primary endpoints.

RESULTS

Among 33 patients included, 32 patients (97%) received CRT and 26 (78.8%) were resected (R0 resection for all patients resected). Among resected patients, we report pathCR in 23,1% and pathologic major response (tumor regression grade 2 according to Mandard's classification) in 26,9%. With a median follow-up duration of 5.82 years (range, 0.4 to 9.24 years), the estimated median OS for all 33 patients was not reached; 1-, 3-, and 5-year OS rates were 85%, 61%, and 52%, respectively. Among resected patients, those whose histological response was tumor grade regression (TRG) 1-2 had significantly better OS and PFS rates than those with a TRG 3-4-5 response (p=0.019 and p=0.016, respectively).

CONCLUSION

Promising results from trials involving preoperative chemoradiation followed by surgery in gastric cancer need to be further evaluated in a phase III trial.

Development of a clinical nomogram for prediction of response to neoadjuvant chemotherapy in patients with advanced gastric cancer

BACKGROUND

The efficacy of neoadjuvant chemotherapy (NAC) in advanced gastric cancer (GC) is still a controversial issue.

AIM

To find factors associated with chemosensitivity to NAC treatment and to provide the optimal therapeutic strategies for GC patients receiving NAC.

METHODS

The clinical information was collected from 230 GC patients who received NAC treatment at the Central South University Xiangya School of Medicine Affiliated Haikou Hospital from January 2016 to December 2020. Least absolute shrinkage and selection operator logistic regression analysis was used to find the possible predictors. A nomogram model was employed to predict the response to NAC.

RESULTS

In total 230 patients were finally included in this study, including 154 males (67.0%) and 76 females (33.0%). The mean age was (59.37 ± 10.60) years, ranging from 24 years to 80 years. According to the tumor regression grade standard, there were 95 cases in the obvious response group (grade 0 or grade 1) and 135 cases in the poor response group (grade 2 or grade 3). The obvious response rate was 41.3%. Least absolute shrinkage and selection operator analysis showed that four risk factors significantly related to the efficacy of NAC were tumor location (P < 0.001), histological differentiation (P = 0.001), clinical T stage (P = 0.008), and carbohydrate antigen 724 (P = 0.008). The C-index for the prediction nomogram was 0.806. The calibration curve revealed that the predicted value exhibited good agreement with the actual value. Decision curve analysis showed that the nomogram had a good value in clinical application.

CONCLUSION

A nomogram combining tumor location, histological differentiation, clinical T stage, and carbohydrate antigen 724 showed satisfactory predictive power to the response of NAC and can be used by gastrointestinal surgeons to determine the optimal treatment strategies for advanced GC patients.

Imaging advances in efficacy assessment of gastric cancer neoadjuvant chemotherapy

Effective neoadjuvant chemotherapy (NAC) can improve the survival of patients with locally progressive gastric cancer, but chemotherapeutics do not always exhibit good efficacy in all patients. Therefore, accurate preoperative evaluation of the effect of neoadjuvant therapy and the appropriate selection of surgery time to minimize toxicity and complications while prolonging patient survival are key issues that need to be addressed. This paper reviews the role of three imaging methods, morphological, functional, radiomics, and artificial intelligence (AI)-based imaging, in evaluating NAC pathological reactions for gastric cancer. In addition, the advantages and disadvantages of each method and the future application prospects are discussed.

Tumor regression grade combined with post-therapy lymph node status: A novel independent prognostic factor for patients treated with neoadjuvant therapy followed by surgery in locally advanced gastroesophageal junction and gastric carcinoma

BACKGROUND

Tumor regression grade (TRG) is a measure of histopathological response to neoadjuvant therapy (NAT). Post-therapy lymph node (ypN) metastasis was reported as a prognostic factor. However, the evaluation of the treatment effectiveness of NAT has not been well studied. Here, we explored whether TRG combined with ypN status could be a prognostic factor for gastroesophageal junction (GEJ) and gastric cancer (GC). Besides, we aimed at making clear the association of different neoadjuvant regimens with different TRG and ypN status.

METHODS

376 patients with GEJ or GC accepting NAT in Peking University Cancer Hospital were retrospectively collected from January 1, 2003 to June 30, 2021. According to TRG and ypN status, patients were innovatively categorized into four groups: TRG0N0, TRG1-3N0, TRG0-1N+, and TRG2-3N+. We applied Kaplan-Meier method and log-rank test to testify the differences in disease free survival (DFS) and overall survival (OS) among four groups. Univariate and multivariate analyses were performed to examine the relationships between TRG combined with ypN status and prognosis.

RESULTS

We observed significant survival differences among the four groups (p < 0.001, respectively). Median DFS and OS of patients with TRG0N0, TRG1-3N0, and TRG0-1N+ were not reached, whereas these of patients with TRG2-3N+ were 17.37 months (95% CI, 14.14-20.60 months) and 39.97 months (95% CI, 27.05-52.89 months). TRG combined with ypN status was still an independent predictor for both DFS (p < 0.001) and OS (p < 0.001) in multivariate analysis. Chi-squared test showed TRG combined with ypN status was significantly associated with different preoperative treatments (p < 0.001). Patients receiving immunotherapy achieved the highest TRG0N0 rate (31.9%).

CONCLUSION

Our results demonstrate that TRG combined with ypN status is a novel independent predictor of both DFS and OS in resectable, locally advanced GEJ and GC. Neoadjuvant immunotherapy achieved the highest TRG0N0 rate.

Imaging lymph node regression can predict the pathological tumor regression grade in gastric cancer after neoadjuvant treatment

BACKGROUND

Neoadjuvant chemotherapy has become the standard treatment for locally advanced gastric cancer. The tumor regression grade system is an effective and widely used tool for the evaluation of treatment response to neoadjuvant chemotherapy. However, whether tumor regression grade could be predicted using clinical characteristics is uncertain.

METHODS

A total of 287 locally advanced gastric cancer patients from 2014 to 2021 were retrospectively included. According to the College of American Pathologists' tumor regression grade system, patients were classified into response group (tumor regression grade 0-1) and non-response group (tumor regression grade 2-3). Associations between clinical characteristics and neoadjuvant chemotherapy response were performed by the logistic regression model. The Kaplan-Meier method was used to estimate the survival. A prediction scoring system was constructed based on the β coefficients of multivariate analysis. The receiver operating characteristic curve and decision curve analysis were used to evaluate the performance of the predictive scoring system.

RESULTS

Survival analysis showed that patients with tumor regression grades 0 to 1 had significantly better disease-free survival and overall survival than the tumor regression grades 2 to 3. Tumor differentiation, ycT stage, immunotherapy, and lymph node regression were independent predictors of pathological response to neoadjuvant chemotherapy. We further developed a scoring system to predict the tumor regression grade. The receiver operating characteristic and decision curve analysis showed good predictive performance of the scoring system.

CONCLUSION

Lymph node regression could be used as a predictor for pathological response. We developed a scoring system to predict the treatment response of patients with gastric cancer receiving neoadjuvant chemotherapy. The scoring system based on the predictors could provide guidance for making clinical decisions.

ApoA-I and ApoB levels, and ApoB-to-ApoA-I ratio as candidate pre-treatment biomarkers of pathomorphological response to neoadjuvant therapy in gastric and esophago-gastric junction adenocarcinoma

<b><br>Introduction:</b> Neoadjuvant chemotherapy (NAC) is a part of the current standard of care in a locally advanced gastric adenocarcinoma (GA) and esophagogastric junction adenocarcinoma (EGJA), but only patients with good pathomorphological response (pR) to NAC benefit from prolonged overall survival.</br> <b><br>Aim:</b> The study aims to evaluate ApoA-I and ApoB as candidate pre-treatment biomarkers of pR to NAC in patients with GA and EGJA.</br> <b><br>Materials and methods:</b> Serum samples were collected from 18 patients with GA and 9 with EGJA before the initiation of NAC to determine the ApoA-I and ApoB levels. After NAC tumor regression grade (TRG) was evaluated in resected specimens according to the Mandard's tumor regression grading system and correlated with pre-treatment ApoA-I and ApoB serum concentration, and ApoB-to-ApoA-I serum concentration ratio.</br> <b><br>Results:</b> We found a positive correlation of ApoA-I level and pR (95% CI: -0.863 to -0.467; P < 0.0001), a negative correlation of ApoB level and pR (95% CI: 0.445 to 0.857; P < 0.0001), a negative correlation of ApoB-to-ApoA-I ratio and pR (95% CI: 0.835 to 0.964; P < 0.0001).</br> <b><br>Conclusions:</b> ApoA-I and ApoB levels, and ApoB-to-ApoA-I ratio are candidate pre-treatment predictors of pR to NAC in GA and may help to guide personalized therapy.</br>Our work fits into the dynamically developing trend of personalized treatment. It describes a potentially important rationale for further evaluation of apolipoprotein A-I and apolipoprotein B as predictors of cancer response to neoadjuvant therapy.

Is Pathologic Complete Response a Good Predictor for the Long-Term, Clinical Outcome in Patients with Gastric Cancer After Neoadjuvant Chemotherapy? A Retrospective, Multi-institution Study in China

BACKGROUND

Many studies have used pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) as the primary endpoint for the short-term efficacy in gastric cancer, but whether it is a good indicator for overall survival is poorly understood.

METHODS

This study reviewed a multi-institution database of patients who underwent radical gastrectomy and achieved pCR after NAC. Cox regression models were used to identify clinicopathologic predictors of overall survival (OS) and disease-free survival (DFS). Survival curves were calculated by using the Kaplan-Meier method and compared by means of the log-rank test.

RESULTS

OS and DFS in patients with pCR were significantly higher than in those with non-pCR (both P < 0.001). Multivariable analysis confirmed pCR was an independent prognostic factor for OS and DFS (P = 0.009 and P = 0.002 for OS and DFS, respectively). However, the survival benefit for pCR was present only for ypN0 tumors (P = 0.004 and P = 0.001 for OS and DFS, respectively), and OS (P = 0.292) and DFS (P = 0.285) among patients with ypN+ gastric cancer could not be stratified by pCR.

CONCLUSIONS

In our study, pCR is an independent prognostic factor for OS and DFS, but the survival benefit for pCR is present only for ypN0 tumors but not ypN+ tumors.

Digital histopathological images of biopsy predict response to neoadjuvant chemotherapy for locally advanced gastric cancer

BACKGROUND

Neoadjuvant chemotherapy (NAC) has been recognized as an effective therapeutic option for locally advanced gastric cancer as it is expected to reduce tumor size, increase the resection rate, and improve overall survival. However, for patients who are not responsive to NAC, the best operation timing may be missed together with suffering from side effects. Therefore, it is paramount to differentiate potential respondents from non-respondents. Histopathological images contain rich and complex data that can be exploited to study cancers. We assessed the ability of a novel deep learning (DL)-based biomarker to predict pathological responses from images of hematoxylin and eosin (H&E)-stained tissue.

METHODS

In this multicentre observational study, H&E-stained biopsy sections of patients with gastric cancer were collected from four hospitals. All patients underwent NAC followed by gastrectomy. The Becker tumor regression grading (TRG) system was used to evaluate the pathologic chemotherapy response. Based on H&E-stained slides of biopsies, DL methods (Inception-V3, Xception, EfficientNet-B5, and ensemble CRSNet models) were employed to predict the pathological response by scoring the tumor tissue to obtain a histopathological biomarker, the chemotherapy response score (CRS). The predictive performance of the CRSNet was evaluated.

RESULTS

69,564 patches from 230 whole-slide images of 213 patients with gastric cancer were obtained in this study. Based on the F1 score and area under the curve (AUC), an optimal model was finally chosen, named the CRSNet model. Using the ensemble CRSNet model, the response score derived from H&E staining images reached an AUC of 0.936 in the internal test cohort and 0.923 in the external validation cohort for predicting pathological response. The CRS of major responders was significantly higher than that of minor responders in both internal and external test cohorts (both p < 0.001).

CONCLUSION

In this study, the proposed DL-based biomarker (CRSNet model) derived from histopathological images of the biopsy showed potential as a clinical aid for predicting the response to NAC in patients with locally advanced GC. Therefore, the CRSNet model provides a novel tool for the individualized management of locally advanced gastric cancer.

Interpretation of Tumor Response Grade following Preoperative Therapy for Gastric Cancer: An Overview

Gastric cancer is among the top five causes of cancer-related death worldwide. Preoperative chemotherapy has been established as an option in patients with locally advanced gastric cancer. However, chemotherapy yields variable results, owing to the cellular and molecular heterogeneity of this disease. Identifying patients who did or did not respond to preoperative therapy can allow clinicians to alter treatment modalities and provide important information related to prognostication. A pathologic response to preoperative therapies, called the Tumor Response Grade (TRG), has been evaluated to quantify treatment response. Multiple systems for TRG have been established. However, the literature has demonstrated inconsistent results for TRG systems and prognosis, possibly due to variability in interpretation of tumor response between systems and interobserver variability. Radiographic responses to preoperative therapies using RECIST 1.1 criteria and endoscopically assessed tumor response have demonstrated association with survival; however, their use in gastric cancer remains challenging given the inability to accurately and consistently identify and measure the tumor, especially in the setting of neoadjuvant therapy, where treatment-related changes can obscure the gastric wall layers. While the response to preoperative therapies with positron emission tomography (PET) has shown promising results in esophageal and esophagogastric junction (EGJ) malignancies, its role in gastric cancer is still under investigation. This review is focused on summarizing the available literature related to evaluating TRG in gastric cancer, as well as providing a brief overview of the use of radiographic and endoscopic methods to assess response to preoperative therapies. Lastly, we outline future directions regarding the use of a universal TRG system to guide care and assist with prognosis.

A Novel ypTLM Staging System Based on LODDS for Gastric Cancer After Neoadjuvant Therapy: Multicenter and Large-Sample Retrospective Study

BACKGROUND

The accuracy of the eighth AJCC ypTNM staging system on the prognosis of gastric cancer (GC) patients after neoadjuvant therapy (NAT) is controversial. This study aimed to develop and validate a novel staging system using the log odds of positive lymph nodes scheme (LODDS).

METHODS

A retrospective analysis of 606 GC patients who underwent radical gastrectomy after neoadjuvant therapy was conducted as the development cohort. (Fujian Medical University Affiliated Union Hospital (n = 183), Qinghai University Affiliated Hospital (n = 169), Mayo Clinic (n = 236), Lanzhou University First Hospital (n = 18)). The validation cohort came from the SEER database (n = 1701). A novel ypTLoddsS (ypTLM) staging system was established using the 3-year overall survival. The predictive performance of two systems was compared.

RESULTS

Two-step multivariate Cox regression analysis in both cohorts showed that ypTLM was an independent predictor of overall survival of GC patients after neoadjuvant therapy (HR: 1.57, 95% CI: 1.30-1.88, p < 0.001). In the development cohort, ypTLM had better discrimination ability than ypTNM (C-index: 0.663 vs 0.633, p < 0.001), better prediction homogeneity (LR: 97.7 vs. 70.9), and better prediction accuracy (BIC: 3067.01 vs 3093.82; NRI: 0.36). In the validation cohort, ypTLM had a better prognostic predictive ability (C-index: 0.614 vs 0.588, p < 0.001; LR: 11,909.05 vs. 11,975.75; BIC: 13,263.71 vs 13,328.24; NRI: 0.22). The time-dependent ROC curve shows that the predictive performance of ypTLM is better than ypTNM, and the analysis of the decision curve shows that ypTLM achieved better net benefits.

CONCLUSION

A LODDS-based ypTLM staging system based on multicenter data was established and validated. The predictive performance was superior to the eighth AJCC ypTNM staging system.

Risk model and factors for prediction of response to neoadjuvant chemotherapy in patients with advanced gastric cancer-a two-center cohort study

OBJECTIVE

Due to inconsistency in neoadjuvant chemotherapy (NACT) response in advanced gastric cancer (GC), the indications remain the source of controversy. This study focused on identifying factors related to NACT chemosensitivity and providing the best treatment for GC cases.

METHODS

Clinical data in 867 GC cases treated with neoadjuvant chemotherapy were downloaded from two medical centers between January 2014 and December 2020, and analyzed by logistic regression and the least absolute shrinkage and selection operator (LASSO) for identifying potential factors that predicted NACT response and might be incorporated in constructing the prediction nomogram.

RESULTS

After the inclusion and exclusion criteria were applied, totally 460 cases were enrolled, among which, 307 were males (66.74%) whereas 153 were females (33.26%), with the age of 24-77 (average, 59.37 ± 10.60) years. Consistent with RECIST standard, 242 patients were classified into effective group (PR or CR) while 218 were into ineffective group (PD or SD), with the effective rate of 52.61%. In training set, LASSO and logistic regression analysis showed that five risk factors were significantly associated with NACT effectiveness, including tumor location, Smoking history, T and N stages, and differentiation. In terms of our prediction model, its C-index was 0.842. Moreover, calibration curve showed that the model-predicted results were in good consistence with actual results. Validation based on internal and external validation sets exhibited consistency between training set results and ours.

CONCLUSIONS

This study identified five risk factors which were significantly associated with NACT response, including smoking history, clinical T stage, clinical N stage, tumor location and differentiation. The prediction model that exhibited satisfying ability to predict NACT effectiveness was constructed, which may be adopted for identifying the best therapeutic strategy for advanced GC by gastrointestinal surgeons.

Staging LaParoscopy to Assess Lymph NOde InvoLvement in Advanced GAstric Cancer (POLA)-Study protocol for a single-arm prospective observational multicenter study

INTRODUCTION

In the era of neoadjuvant chemotherapy in advanced gastric cancer (GC), the role of staging laparoscopy (SL) will become more established. However, despite guidelines recommendations, SL for optimal preoperative staging remains underutilized. Diagnostic value of near-infrared (NIR) / indocyanine green (ICG) guided sentinel node (SN) mapping in GC confirmed its technical feasibility, however no data exist regarding its potential role in pathological nodal staging. To the best of our knowledge, current study is the first to evaluate the role of ICG in nodal staging of advanced GC patients undergoing SL.

MATERIALS AND METHODS

This single-arm prospective observational multicenter study was approved by the Bioethical Committee of Medical University of Lublin (Ethic Code: KE-0254/331/2018). The protocol is registered at clinicaltrial.gov (NCT05720598), and the study results will be reported according to the Strengthening of Reporting of Observational Studies in Epidemiology (STROBE) statement. The primary endpoint of this study is the identification rate of ICG-guided SN in advanced GC patients. The secondary endpoints include pathological and molecular assessment of retrieved SNs and other pretreatment clinical variables potentially associated with SL: pattern of perigastric ICG distribution according to patients' pathological and clinical characteristics, neoadjuvant chemotherapy compliance, 30-day morbidity, and mortality.

CONCLUSION

POLA study is the first to investigate the clinical value of ICG-enhanced sentinel node biopsy during staging laparoscopy in advanced GC patients in a Western cohort. Identifying pN status before multimodal treatment will improve GC staging process.

Pathological complete response in multimodal treatment of esophageal cancer: a retrospective cohort study

To evaluate pathological complete response (pCR, ypT0ypN0) after neoadjuvant treatment compared with non-complete response (non-CR) in patients with esophageal cancer (EC), and 393 patients were retrospectively analyzed. Survival probability was analyzed in patients with: (i) pCR vs non-CR; (ii) complete response of the primary tumor but persisting lymphatic metastases (non-CR-T0N+) and (iii) pCR and tumor-free lymphnodes exhibiting signs of postneoadjuvant regression vs. no signs of regression. (i) Median overall survival (mOS) was favorable in patients with pCR (pCR: mOS not reached vs. non-CR: 41 months, P < 0.001). Multivariate analysis revealed that grade of regression was not an independent predictor for prolonged survival. Instead, the achieved postneoadjuvant TNM-stage (T-stage: Hazard ratio [HR] ypT3-T4 vs. ypT0-T2: 1.837; N-stage: HR ypN1-N3 vs. ypN0: 2.046; Postneoadjuvant M-stage: HR ypM1 vs. ycM0: 2.709), the residual tumor (R)-classification (HR R1 vs. R0: 4.195) and the histologic subtype of EC (HR ESCC vs. EAC: 1.688) were prognostic factors. Patients with non-CR-T0N+ have a devastating prognosis, similar to those with local non-CR and lymphatic metastases (non-CR-T + N+) (non-CR-T0N+: 22.0 months, non-CR-T + N-: mOS not reached, non-CR-T + N+: 23.0 months; P-values: non-CR-T0N+ vs. non-CR-T + N-: 0.016; non-CR-T0N+ vs. non-CR-T + N+: 0.956; non-CR-T + N- vs. non-CR-T + N+: <0.001). Regressive changes in lymphnodes after neoadjuvant treatment did not influence survival-probability in patients with pCR (mOS not reached in each group; EAC-patients: P = 0.0919; ESCC-patients: P = 0.828). Particularly, the achieved postneoadjuvant ypTNM-stage influences the survival probability of patients with EC. Patients with non-CR-T0N+ have a dismal prognosis, and only true pathological complete response with ypT0ypN0 offers superior survival probabilities.

Response to neoadjuvant paclitaxel predicts survival in anaplastic thyroid carcinoma

The clinical utilities of paclitaxel in anaplastic thyroid carcinoma (ATC) have been reported. The current study investigated the outcomes in ATC patients treated by paclitaxel as neoadjuvant setting. Furthermore, the prognostic factor for overall survival (OS) and predictive marker for response to paclitaxel were investigated. Records of ATC patients treated by paclitaxel as neoadjuvant setting in our hospital were reviewed. The median OS for the patients with (n = 43) and without (n = 23) resection were 14.7 (95% CI, 11.0-21.7) and 4.2 (95% CI, 3.0-5.4) months, respectively (p < 0.001). Univariate analysis identified the factors of stage (p = 0.028), prognostic index (PI) ≥2 (p < 0.001), response to paclitaxel (p = 0.007), resection (p < 0.001), and radiotherapy (p < 0.001) to be associated with OS, and multivariate analysis revealed that the factors of PI ≥2 [hazard ratio (HR), 2.406 (95% CI, 1.096-5.281), p = 0.029], response to paclitaxel [HR, 0.423 (95% CI, 0.193-0.930), p = 0.032], resection [HR, 0.316 (95% CI, 0.129-0.773), p = 0.012], and radiotherapy [HR, 0.229 (95% CI, 0.100-0.526), p < 0.001] were independent prognostic factors of OS. There were no significant predictive factors for response to paclitaxel in baseline characteristics. PI ≥2, response to paclitaxel, resection, and radiotherapy were independent prognostic factors in ATC patients treated with paclitaxel as neoadjuvant setting. It is important to investigate predictor for response to paclitaxel for improving resectability and prognosis in ATC.

Prognostic Value of Tumor Regression Grading in Patients Treated With Neoadjuvant Chemotherapy Plus Surgery for Gastric Cancer

Objective

To validate the prognostic value of tumor regression grading (TRG) and to explore the associated factors of TRG for advanced gastric cancer (AGC) with neoadjuvant chemotherapy (NACT) plus surgery.

Methods

Two hundred forty-nine AGC patients treated with NACT followed by gastrectomy at the Mayo Clinic, USA and the Fujian Medical University Union Hospital, China between January 2000 and December 2016 were enrolled in this study. Cox regression was used to identify covariates associated with overall survival (OS) and recurrence-free survival (RFS). Logistic regression was used to reveal factors predicting tumor regression grading.

Results

For patients with TRG 0-1, the 3- and 5-year OS rates were 85.2% and 74.5%, respectively, when compared to 56.1% and 44.1% in patients with TRG 2 and 28.2% and 23.0% in patients with TRG 3, respectively (p<0.001). TRGs were independent risk factors for OS. Similar findings were observed in RFS. Multivariable analysis revealed that an oxaliplatin-based regimen (p=0.017) was an independent predictor of TRG. The oxaliplatin-based regimen was superior to the nonoxaliplatin-based regimen for OS (38.4 months vs 19.5 months, respectively; p=0.01). Subgroup analyses by histological subtype indicated that the oxaliplatin-based regimen improved the OS in nonsignet ring cell carcinoma compared to the nonoxaliplatin-based regimen (53.7 months vs 19.5 months, respectively; p=0.011). However, similar findings were not observed in RFS.

Conclusion

TRG was an independent factor of AGC treated with neoadjuvant chemotherapy plus surgery. Oxaliplatin-based neoadjuvant chemotherapy regimens improve tumor response and may have an overall survival benefit for patients with nonsignet ring cell carcinoma.

Evaluation of dual-energy CT derived radiomics signatures in predicting outcomes in patients with advanced gastric cancer after neoadjuvant chemotherapy

BACKGROUND

To investigate the prognostic value of dual-energy CT (DECT) based radiomics to predict disease-free survival (DFS) and overall survival (OS) for patients with advanced gastric cancer (AGC) after neoadjuvant chemotherapy (NAC).

METHODS

From January 2014 to December 2018, a total of 156 AGC patients were enrolled and randomly allocated into a training cohort and a testing cohort at a ratio of 2:1. Volume of interest of primary tumor was delineated on eight image series. Four feature sets derived from pre-NAC and delta radiomics were generated for each survival arm. Random survival forest was used for generating the optimal radiomics signature (RS). Statistical metrics for model evaluation included Harrell's concordance index (C-index) and the average cumulative/dynamic AUC throughout follow-up. A clinical model and a combined Rad-clinical model were built for comparison.

RESULTS

The pre-IU (derived from iodine uptake images before NAC) RS performed best for DFS and OS in the testing cohort (C-indices, 0.784 and 0.698; the average cumulative/dynamic AUCs, 0.80 and 0.77). When compared with the clinical model, the radiomics model had significantly higher C-index to predict DFS in the testing cohort (0.784 vs. 0.635, p < 0.001), but no statistical difference was found for OS (0.698 vs. 0.680, p = 0.473). The combined Rad-clinical models showed improved performance in the testing cohort, with C-indices of 0.810 and 0.710 for DFS and OS, respectively.

CONCLUSION

DECT-derived radiomics serves as a promising non-invasive biomarker to predict survival for AGC patients after NAC, providing an opportunity for transforming proper treatment.

A Machine Learning Model for Predicting a Major Response to Neoadjuvant Chemotherapy in Advanced Gastric Cancer

Aims

To develop and validate a model for predicting major pathological response to neoadjuvant chemotherapy (NAC) in advanced gastric cancer (AGC) based on a machine learning algorithm.

Method

A total of 221 patients who underwent NAC and radical gastrectomy between February 2013 and September 2020 were enrolled in this study. A total of 144 patients were assigned to the training cohort for model building, and 77 patients were assigned to the validation cohort. A major pathological response was defined as primary tumor regressing to ypT0 or T1. Radiomic features extracted from venous-phase computed tomography (CT) images were selected by machine learning algorithms to calculate a radscore. Together with other clinical variables selected by univariate analysis, the radscores were included in a binary logistic regression analysis to construct an integrated prediction model. The data obtained for the validation cohort were used to test the predictive accuracy of the model.

Result

A total of 27.6% (61/221) patients achieved a major pathological response. Five features of 572 radiomic features were selected to calculate the radscores. The final established model incorporates adenocarcinoma differentiation and radscores. The model showed satisfactory predictive accuracy with a C-index of 0.763 and good fitting between the validation data and the model in the calibration curve.

Conclusion

A prediction model incorporating adenocarcinoma differentiation and radscores was developed and validated. The model helps stratify patients according to their potential sensitivity to NAC and could serve as an individualized treatment strategy-making tool for AGC patients.

Tumor Regression Grade in Gastric Cancer After Preoperative Therapy

BACKGROUND

The Cancer Staging Manual, 8th edition, now includes post-neoadjuvant therapy (ypTNM) staging for gastric cancer patients. Our purpose was to determine whether the tumor regression grade (TRG) of the primary tumor is useful for predicting the survival of these patients.

METHODS

We performed a retrospective review of an institutional database and identified patients with clinically non-metastatic gastric adenocarcinoma who underwent preoperative chemotherapy or chemoradiation therapy before gastrectomy. Pathology reports were reviewed, and TRG was classified as follows: 0 (complete response), 1 (viable tumor cells ≤ 1-2%), 2 (viable cells ≤ 50%), or 3 (viable cells > 50%).

RESULTS

Of the 356 patients identified, including 80 (23%) with a gastroesophageal junction tumor, 268 (75%) had undergone preoperative chemoradiation therapy. Fifty-six (16%) had TRG 0, 57 (16%) TRG 1, 128 (36%) TRG 2, and 115 (32%) TRG 3. No association between TRG and pretreatment factors was identified, except for signet-ring cell histologic type and tumor location. A higher TRG was associated with more advanced ypT and ypN categories (both p < 0.001), ypM1 (p = 0.004), and R1 resection (p = 0.052). The median overall survival (OS) duration was 6.6 years, and the 5-year OS rate was 54.1%. TRG 3 was associated with a shorter OS duration than were other TRG scores (p = 0.015), while the OS did not differ significantly among the TRG 0-2 groups (p = 0.803). On multivariable analysis, TRG was not associated with OS after adjustment for ypN status.

CONCLUSION

In gastric cancer patients who underwent preoperative therapy, TRG 3 was associated with advanced ypStage and R1 resection. Patients with TRG 3 had a shorter OS duration because of associated advanced ypStage, particularly ypN+ status.

Lymph Node Involvement in Advanced Gastric Cancer in the Era of Multimodal Treatment-Oncological and Surgical Perspective

Simple Summary

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Therefore, further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Abstract

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. A favourable prognostic impact for ypN0 patients is observed, either due to truly negative LN before the start of therapy or because preoperative therapy achieved a pathologically complete nodal response. Ongoing trials investigating the extent of lymphadenectomy after neoadjuvant therapy will standardise the LN dissection from the multimodal therapy perspective. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Short-term results of a phase II study of preoperative docetaxel/cisplatin/S-1 therapy for locally advanced gastric cancer

Background

A multi-institutional phase II study was conducted to evaluate the efficacy and safety of preoperative docetaxel, cisplatin and S-1 therapy in marginally resectable advanced gastric cancer.

Methods

Patients with macroscopic type 4, large macroscopic type 3 and bulky lymph node metastasis received two cycles of preoperative docetaxel, cisplatin and S-1 therapy (docetaxel 40 mg/m² and cisplatin 60 mg/m² on day 1, and S-1 80 mg/m² for 14 days, every 4 weeks). The primary endpoint was the pathological response rate, with an expected value of 65%.

Results

Thirty-one patients were enrolled in this study. The pathological response rate was 54.8%, and it was higher than the threshold value but lower than the expected rate. The R0 resection rate was 93.5%. The frequencies of grade 3–4 toxicities during docetaxel, cisplatin and S-1 therapy were 41.9% for neutropenia, 6.5% for febrile neutropenia and 32.3% for nausea/vomiting. Grade 2 and 3 surgical morbidities occurred in 23.3 and 6.7% of the patients, respectively.

Conclusions

Preoperative docetaxel, cisplatin and S-1 therapy was feasible in terms of chemotherapy-related toxicities and surgical morbidity, but the effect did not achieve the expected value. The association between the pathological response rate and survival will be evaluated in the final analysis of this clinical trial.

Predictors and significance of histologic response to neoadjuvant therapy for gastric cancer

BACKGROUND

Perioperative therapy is the standard-of-care for locally-advanced gastric cancer but many patients do not respond. There are currently no known factors that predict response to therapy.

METHODS

This was a retrospective study aimed to evaluate treatment effect grade (TEG) in patients with locally advanced gastric cancer treated with neoadjuvant therapy and surgery at a single center. Ordinal logistic regression was performed to identify predictors of TEG, scaled from 0 to 3.

RESULTS

Fifty patients were identified. The majority were male (n = 33) and 50% were Hispanic. The most common regimens given were: 5-fluorouracil/leucovorin, oxaliplatin, and docetaxel (n = 23, 46%), epirubicin, cis- or oxaliplatin, and 5-fluorouracil/leucovorin or Xeloda (n = 8, 16%), and 5-fluorouracil/leucovorin and oxaliplatin (n = 9, 18%). Twenty-seven patients (55%) had complete or partial response to therapy (TEG 0-2), and 23 patients (46%) had no response (TEG 3). Of numerous variables analyzed, only race and SRC histology were associated with TEG. TEG was associated with disease free, but not disease specific survival.

CONCLUSIONS

In this cohort, 46% of patients had no histologic response to therapy. SRC histology, and possibly race, should be considered in determination of optimal multidisciplinary regimens and in amount of therapy to be given upfront, as patients with SRC histology and those of non-Asian race are less likely to respond to standard regimens.

Posttherapy topographical nodal status, ypN-site, predicts survival of patients who received neoadjuvant chemotherapy followed by curative surgical resection for non-type 4 locally advanced gastric cancer: supplementary analysis of JCOG1004-A

BACKGROUND

Perioperative treatment is an accepted standard approach for treating locally advanced gastric cancer (LAGC). Histopathological tumor regression with < 10% residual tumor is a globally accepted prognosticator in LAGC patients who received neoadjuvant chemotherapy (NAC) and curative surgery. However, despite a response of the primary tumor, a significant percentage of patients dies from recurrence and identification of those at risk for relapse remains challenging. We re-estimated the value of histopathological tumor regression as a prognosticator alongside other factors, especially posttherapy topographical nodal status, ypN-site.

PATIENTS AND METHODS

Individual patient data including clinicopathological variables were used from the four JCOG trials investigating NAC (JCOG0001, JCOG0002, JCOG0210, JCOG0405) for analyzing prognosticators in patients with curative surgery excluding those with type 4 AGC by univariable and multivariable Cox regression analyses.

RESULTS

Among 85 patients, 5-year overall survival (OS) was 46.0% [95% confidence interval (CI) 35.0-56.4] with a median follow-up of 3.2 years. On univariable analysis, histopathological tumor regression with ≥ 10% residual tumor and ypN-site 2-3 were negatively associated with OS [≥ 10% residual tumor: hazard ratio (HR) 2.60; 95% CI 1.22-5.54; P = 0.014; ypN2-3: HR 3.59; 95% CI 1.60-8.06; P = 0.002). On multivariable analysis, only ypN-site 2-3 was predictive of OS (HR 3.67; 95% CI 1.55-8.69; P = 0.003), whereas histopathological tumor regression with ≥ 10% residual tumor was not (HR 2.24; 95% CI 0.98-5.10; P = 0.055).

CONCLUSIONS

ypN-site may have greater impact on OS than histopathological tumor regression in patients who received NAC plus surgery for non-type 4 LAGC.

Prognostic and Predictive Value of NAR Score in Gastric Cancer

INTRODUCTION

Neoadjuvant treatment is a widely accepted approach for locally advanced rectum cancer. Efforts to explore a surrogate endpoint for clinical trials revealed a new prognostic scoring system which is named as neoadjuvant rectal score (NAR) in patients who received neoadjuvant treatment for rectal cancer.

MATERIAL AND METHODS

88 patients who met inclusion criteria were included in the study. The optimal cutoff value of the NAR score was 17.6 with 71% sensitivity and 63% specificity. Patients with NAR score > 17.6 (n: 48, 54%) were defined as the high-risk group and those with NAR score ≤ 17.6 (n: 40, 56%) as the low-risk group.

RESULT

Survival analysis according to the NAR score group (low-risk vs high-risk) revealed that there was a statistically significant difference between groups regarding OS and DFS. The median OS for high-risk patients was 27.3 months (95% CI, 15.0-39.6); it was 76.6 months (47.3-106.0) for low-risk patients (p < 0.0001). The median DFS was 15.1 months (11.8-18.4) for high-risk patients; it was 44.3 months (95% CI, 4.1-84.6) in the low-risk group (p = 0.002).

DISCUSSION

As a result, we interpreted our findings as supporting data about the utility of NAR score not only as a surrogate endpoint for the clinical trial of rectal cancer but also as a prognostic marker in patients with gastric cancer who received neoadjuvant treatment.

Preoperative Therapy Regimen Influences the Incidence and Implication of Nodal Downstaging in Patients with Gastric Cancer

Purpose

Nodal downstaging after preoperative therapy for gastric cancer has been shown to impart excellent prognosis, but this has not been validated in a national cohort. The role of neoadjuvant chemoradiation (NACR) in nodal downstaging remains unclear when compared with that of neoadjuvant chemotherapy alone (NAC). Furthermore, it is unknown whether the prognostic implications of nodal downstaging differ by preoperative regimen.

Materials and Methods

Using the National Cancer Database, overall survival (OS) duration was compared among natural N0 (cN0/ypN0), downstaged N0 (cN+/ypN0), and node-positive (ypN+) gastric cancer patients treated with NACR or NAC. Factors associated with nodal downstaging were examined in a propensity score-matched cohort of cN+ patients, matched 1:1 by receipt of NACR or NAC.

Results

Of 7,426 patients (natural N0 [n=1,858, 25.4%], downstaged N0 [n=1,813, 24.4%], node-positive [n=3,755, 50.4%]), 58.2% received NACR, and 41.9% received NAC. The median OS durations of downstaged N0 (5.1 years) and natural N0 (5.6 years) patients were similar to one another and longer than that of node-positive patients (2.1 years) (P<0.001). In the matched cohort of cN+ patients, more recent diagnosis (2010–2015 vs. 2004–2009) (odds ratio [OR], 2.57; P<0.001) and NACR (OR, 2.02; P<0.001) were independently associated with nodal downstaging. The 5-year OS rate of downstaged N0 patients was significantly lower after NACR (46.4%) than after NAC (57.7%) (P=0.003).

Conclusions

Downstaged N0 patients have the same prognosis as natural N0 patients. Nodal downstaging occurred more frequently after NACR; however, the survival benefit of nodal downstaging after NACR may be less than that when such is achieved by NAC.

Response to Neoadjuvant Treatment is Influenced by Grade in Gastric Cancer

Neoadjuvant therapy is commonly used in the management of gastric cancer. Primary tumor response to treatment correlates with prognosis. Published studies have compared efficacy of neoadjuvant therapy based on stage but not grade. The objective of this study was to determine the change in staging of gastric cancer after neoadjuvant therapy and resection based on grade. A retrospective analysis of gastric cancer patients treated at our institution between 2005 and 2017 was performed. Patient demographics, tumor characteristics, clinical and pathological stage, and microscopic treatment response were analyzed based on grade. Of the 269 patients identified during this period, 82 patients underwent definitive surgical resection, of which 38 patients received neoadjuvant therapy (low grade (grades 1 and 2), n = 17; high grade (grade 3), n = 18; and unknown grade, n = 3). Pathologic downstaging was observed in 52.9 per cent (9/17) of low-grade tumors compared with 22.2 per cent (4/18) of high-grade tumors. Majority of high-grade tumors (77.8%, 14/18) had either upstaging or unchanged stage. High-grade gastric cancers often lack response to neoadjuvant therapy. Novel targeted therapies based on biologic behavior should be evaluated and incorporated into neoadjuvant treatment. Neoadjuvant studies should stratify patients based on grade and report response by grade.

Impact of tumor regression grade on recurrence after preoperative chemoradiation and gastrectomy for gastric cancer

BACKGROUND AND OBJECTIVES

It is unknown whether the degree of response to preoperative therapy correlates with locoregional recurrence (LR) or distant recurrence (DR) after resection of gastric cancer.

METHODS

Patients who underwent resection of gastric adenocarcinoma following chemotherapy and chemoradiation (1995-2015) were reviewed. The tumor regression grade (TRG) was defined by the percentage of viable tumor cells in the specimen (TRG0 = 0%; TRG1 = 1%-2%; TRG2 = 3%-50%; TRG3 ≥ 50%). The relationships among TRG, recurrence-free survival (RFS), LR, and DR were examined.

RESULTS

Two hundred forty-seven patients met the inclusion criteria (TRG0, 52 [21%]; TRG1, 49 [20%]; TRG2, 98 [40%]; TRG3, 48 [19%]). LR and DR occurred in 6.1% and 32.0% of patients, respectively. No patient with TRG0 experienced LR. R1 resection (6%-15%) and LR (6%-8%) rates were similar among TRG1-3 patients. R1 resection was associated with LR (hazard ratio [HR], 17.85; P < .001). ypN status (HR, 2.44; P = .004) and linitis plastica (HR, 2.90; P < .001) were associated with DR. TRG was not independently associated with RFS, LR, or DR.

CONCLUSIONS

TRG0 imparted excellent local control. However, TRG1-3 patients had similar R1 resection rates and therefore similar LR. DR is associated with ypN status and linitis plastica, not TRG.

Nomogram for predicting pathological complete response to neoadjuvant chemotherapy in patients with advanced gastric cancer

BACKGROUND

Survival benefit of neoadjuvant chemotherapy (NAC) for advanced gastric cancer (AGC) is a debatable issue. Studies have shown that the survival benefit of NAC is dependent on the pathological response to chemotherapy drugs. For those who achieve pathological complete response (pCR), NAC significantly prolonged prolapsed-free survival and overall survival. For those with poor response, NAC yielded no survival benefit, only toxicity and increased risk for tumor progression during chemotherapy, which may hinder surgical resection. Thus, predicting pCR to NAC is of great clinical significance and can help achieve individualized treatment in AGC patients.

AIM

To establish a nomogram for predicting pCR to NAC for AGC patients.

METHODS

Two-hundred and eight patients diagnosed with AGC who received NAC followed by resection surgery from March 2012 to July 2019 were enrolled in this study. Their clinical data were retrospectively analyzed by logistic regression analysis to determine the possible predictors for pCR. Based on these predictors, a nomogram model was developed and internally validated using the bootstrap method.

RESULTS

pCR was confirmed in 27 patients (27/208, 13.0%). Multivariate logistic regression analysis showed that higher carcinoembryonic antigen level, lymphocyte ratio, lower monocyte count and tumor differentiation grade were associated with higher pCR. Concordance statistic of the established nomogram was 0.767.

CONCLUSION

A nomogram predicting pCR to NAC was established. Since this nomogram exhibited satisfactory predictive power despite utilizing easily available pretreatment parameters, it can be inferred that this nomogram is practical for the development of personalized treatment strategy for AGC patients.

Evaluation of the prognostic impact of pathologic response to preoperative chemotherapy using Mandard's Tumor Regression Grade (TRG) in gastric adenocarcinoma

BACKGROUND

Perioperative chemotherapy is the gold standard in gastric cancer management. The prognostic significance of pathological response has been investigated in many malignancies, using Tumor Regression Grade (TRG). Its prognostic value in gastric cancer remains poorly known.

AIMS

This study aimed to assess the prognostic value of pathological response to chemotherapy, using Mandard's TRG in gastric cancer, and to identify factors predictive of response to chemotherapy.

METHODS

We retrospectively identified patients with gastric adenocarcinoma from two institutional surgical databases, with preoperative chemotherapy and subsequent gastrectomy. Pathological response was centrally reviewed using Mandard's TRG.

RESULTS

From 325 patients resected from a gastric cancer between 1997 and 2016, 109 underwent a preoperative chemotherapy. 42% were pathologic responders (TRG1-3) and 58% non-responders (TRG4-5). Five-years overall survival (OS) was 35% for non-responders, and 73% for responders (p = 0,006). Five-years disease-free survival (DFS) was 34% for non-responders and 65% for responders (p = 0,013). In multivariate analysis, pathological response was an independent prognostic factor of poor OS: HR = 2.736 (CI95% = 1.335-5.608; p = 0.006) and DFS: HR = 2.241 (CI95% = 1.130-4.446; p = 0.021).

CONCLUSION

TRG after preoperative chemotherapy is an important prognostic factor in patients resected for a gastric adenocarcinoma. Further studies should be performed to evaluate if adjuvant therapy should be adapted to pathological response.

Prognostic impact of pathological complete remission after preoperative irradiation in patients with locally advanced head and neck squamous cell carcinoma: re-analysis of a phase 3 clinical study

PURPOSE

The purpose of this study was to determine the associations between pathological complete remission (pCR) and clinical outcomes in patients with locally advanced head and neck squamous cell carcinoma (HNSCC) who received preoperative radiotherapy or chemoradiotherapy in a phase 3 clinical study.

METHODS

A total of 222 newly diagnostic stage III/IVM0 HNSCC patients were randomly assigned to a preoperative concurrent chemoradiotherapy group (n = 104) or preoperative radiotherapy alone group (n = 118). Over a mean follow-up of 59 months, 72 patients were defined as non-responders to preoperative therapy and subsequently underwent resection of the primary lesion with or without neck dissection. The relationship between the pathological tumor response of the primary lesion and treatment prognosis was analyzed. Kaplan-Meier and Cox regression multivariate analyses were performed to evaluate the impact of pCR on local control (LC), overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS).

RESULTS

Among the 72 non-responders, 25 patients, 10 in the chemotherapy group and 15 in the radiotherapy group, achieved pCR. The 5-year LC, OS, PFS, and DMFS of pCR patients and non-pCR patients were 93.2% vs. 67.7% (p = 0.007), 83.3% vs. 39.7% (p = 0.0006), 76.1% vs. 44.0% (p = 0.009), and 90.4% vs. 56.3% (p = 0.005), respectively. In multivariate analysis, pCR is also an independent prognostic factor in prognosis, with statistically significant differences.

CONCLUSION

pCR after preoperative radiotherapy or concurrent chemoradiotherapy is a good prognostic factor in locally advanced HNSCC.

TRIAL REGISTRATION

Number:ChiCTR-TRC-114004322 Date:05 Mar, 2014.

Does neoadjuvant chemotherapy cancel out the negative survival impact induced by surgical complications after gastrectomy?

BACKGROUND

Postoperative infectious complications (ICs) are associated with a poor prognosis following gastric cancer surgery. Neoadjuvant chemotherapy (NAC) targeting scirrhous-type or bulky nodal disease reportedly exerts a prophylactic effect on the negative impact of ICs. However, a recent study clearly showed that NAC for scirrhous-type disease had no survival benefit. We investigated this prophylactic effect and significant interactions among subgroups of histological response, macroscopic type, and bulky nodal disease.

METHODS

We examined 115 patients who received NAC followed by radical gastrectomy between January 2008 and December 2015. The overall survival (OS) and disease-free survival (DFS) were compared between those with and without ICs. Our cohort included 62 with type 4/giant type 3, 44 with bulky nodal disease/para-aortic nodal disease, and 25 with other diseases.

RESULTS

A histological response was observed in 80 patients (69.5%). Thirty three (28.7%) developed ICs. There was no significant difference in the OS [hazard ratio (HR) 0.96; 95% confidence interval (CI) 0.47-1.99, p = 0.920] or DFS (HR 0.74; 95% CI 0.40-1.38, p = 0.342) by the presence of ICs. The HR was 1.00 in patients who had no response to NAC (grade 0/1a) and 0.95 in those who responded to NAC (grade 1b/2/3). No subgroups showed significant interactions for the OS.

CONCLUSIONS

NAC may cancel out the negative impact of morbidity on the survival in advanced gastric cancer patients. The prophylactic effects by NAC do not depend on the tumor type or histological response.

Graded histologic response after neoadjuvant chemotherapy is an optimal criterion for treatment change in patients with locally advanced gastric cancer

Background

The necessity for changing the postoperative therapy regimen for locally advanced gastric cancer after ineffective neoadjuvant chemotherapy and surgery is unclear because there are no criteria to determine which patients can benefit from this treatment. We assessed whether graded histologic regression of <50% could be the criterion for regimen modification.

Methods

The study was designed as a matched-pair case-control investigation to minimize intergroup heterogeneity. Patients were stratified into two groups in which they either continued in the same course of treatment or changed the regimen to neoadjuvant chemotherapy.

Results

Thirty-six patients were stratified into two groups. The adjuvant chemotherapy regimen of 12 patients was changed, while 24 patients continued on the same regimen. During an average follow-up period of 36 months, there was no difference observed in overall survival in the two groups (median, 24.0 vs. 31.0 months, P=0.863). In a subgroup analysis, however, patients in the changed regimen group with ypTNM stage III disease tended to have superior overall survival, though this effect was not significant (median, 23.0 vs. 14.0 months, P=0.123). Post-therapy nodal status was associated with overall survival in the multivariate analysis (P=0.014, HR 12.503, 95% CI: 1.664-93.919). Most adverse events were categorized as grade 1 or 2, and all treatments were well tolerated.

Conclusions

Changing treatment based on a graded histologic regression of <50% after neoadjuvant chemotherapy did not prolong overall survival in patients with gastric cancer. However, changing the adjuvant regimen did reveal a trend towards improved overall survival in the ypTNM stage III subgroup, which merits further investigation using a larger sample size.

Characteristics and Survival of Gastric Cancer Patients with Pathologic Complete Response to Preoperative Therapy

BACKGROUND

Pathologic complete response of a primary tumor (ypT0) after preoperative therapy is associated with improved overall survival (OS). However, whether other variables are associated with outcome for gastric cancer patients with ypT0 status is unknown.

METHODS

This study reviewed an institutional database of patients who underwent resection of gastric or gastroesophageal adenocarcinoma after preoperative therapy and identified patients with ypT0 status. Cox regression models were used to identify clinicopathologic predictors of OS.

RESULTS

Of 77 patients with ypT0 status identified in this study, 36 (47%) had gastroesophageal junction tumors. At presentation, 62 patients (81%) had clinical T3 disease, and 7 (9%) had clinical T4 disease. The clinical nodal status was positive (cN+) for 45 patients (58%). Preoperative chemoradiation was administered to 75 patients (97%). The median follow-up duration was 3.54 years. The median OS was 10 years, and the 5-year OS rate was 61%. Univariable analysis identified age of 65 years or older at the time of diagnosis, histologic grade, and ypN status as significant predictors of OS. Multivariable analysis confirmed age of 65 years or older [hazard ratio (HR), 4.26; p < 0.001] and persistent nodal disease (ypN+ status; HR, 5.12; p < 0.001) to be independently associated with OS. Clinical stage was not associated with survival. In the subset of ypT0N0 patients, no clinicopathologic feature was predictive of survival.

CONCLUSION

For gastric or gastroesophageal adenocarcinoma patients with ypT0 status after preoperative therapy, ypN+ status substantially reduced survival. Pretreatment clinical stage had no impact on OS for patients with a pathologic complete response.

Blast from the past: Perioperative use of the Maruyama computer program for prediction of lymph node involvement in the surgical treatment of gastric cancer following neoadjuvant chemotherapy

BACKGROUND

Surgical quality assurance is a key element of gastric cancer treatment. The Maruyama Computer Program (MCP) allows to predict lymph node involvement in stations no. 1-16. The aim of the current study was to evaluate the accuracy of the MCP predictions in GC patients treated with neoadjuvant chemotherapy (nCTH) followed by gastrectomy with adequate lymphadenectomy.

METHODS

101 patients who underwent preoperative nCTH followed by D2 gastrectomy with curative intent were analysed. The response to nCTH was measured using the tumour regression grade system.

RESULTS

Test sensitivity, specificity, PPV, NPV and accuracy of the MCP were 92%, 33%, 41%, 89%, and 53%, respectively. In patients with response to nCTH, number of false positive (FP) results was significantly higher than in patients who did not respond to nCTH both in the N1 (56.3% vs 28.9%, p < 0.0001) and in the N2 (59% vs 41%, p < 0.0001) trier. The risk for FP results was 6 times higher in N1 (OR = 6.50, 95%CI: 3.91-10.82,; p < 0.0001) and N2 (OR = 5.84, 95%CI: 2.85-11.96; p < 0.0001) triers. In patients with intestinal type GC, the risk for FP results was 4 times higher than in other histologic types of GC in both N1 (OR = 4.23, 95%CI: 2.58-6.95; p < 0.0001) and N2 (OR = 4.23, 95%CI: 2.02-9.62; p = 0.0002) triers.

CONCLUSIONS

MCP predictions in the GC patients treated with nCTH have low specificity due to significantly high number of FP results. Noticeably low accuracy level of predictions indicate a need for new prediction models, based on Laurén classification, since it may provide some information on expected regression grade.

The Relationship between Primary Gross Tumor Volume and Tumor Response of Locally Advanced Rectal Cancer: pGTV as a More Accurate Tumor Size Indicator

Purpose: To identify the clinical predictive factors of tumor response and to evaluate the significance of primary gross tumor volume (pGTV), obtained from radiotherapy planning, in predicting tumor response. Materials and Methods: We retrospectively analyzed data of consecutive locally advanced rectal cancer (LARC) patients who were treated with neoadjuvant chemoradiotherapy (nCRT) followed by radical surgery at our institution between March 2009 and December 2017. We identify independent predictors of tumor response to nCRT by statistical analysis. Disease-free survival (DFS) starting from the time of surgery was calculated by the Kaplan-Meier method, and log-rank tests were performed to compare DFS between patients with superior and inferior tumor response. Results: Overall, 185 LARC patients received nCRT, of whom 89 (48.11%) achieved superior tumor response. Diminutive pGTV (p = 0.038) and distance from the anal verge (DAV) (p = 0.006) were independent predictive factors of superior tumor response. Meanwhile, pGTV can be regarded as an independent predictor of pathologic complete response (pCR) (p = 0.036). The log-rank test revealed that DFS was longer in the diminutive pGTV group than in the giant pGTV group (p = 0.001). Conclusions: pGTV, as a measure of tumor size, is not only an important prognostic indicator but also an independent predictive factor of tumor response, even pCR.

Proposal of a Nomogram for Predicting Survival in Patients with Siewert Type II Adenocarcinoma of the Esophagogastric Junction After Preoperative Radiation

Background

Preoperative radiotherapy tends to be more frequently used for patients with adenocarcinoma of the esophagogastric junction (AEG); however, the prognostic values of postoperative pathologic characteristics in these patients remain unclear. This study aimed to examine the outcomes in Siewert type II AEG patients receiving preoperative radiotherapy to identify the predictive factors for overall survival (OS).

Methods and Results

A total of 1818 AEG patients undergoing preoperative radiotherapy were reviewed. Univariate analyses showed that age, sex, histology, tumor grade, positive lymph node (PLN), lymph node ratio, and log odds of positive lymph nodes (LODDS) were significantly correlated with OS; however, only age, grade, PLN, and LODDS were identified as independent risk factors in a multivariate regression model. Subsequently, patients were randomly grouped into training and validation cohorts (1:1 ratio), and the beta coefficients of these variables in the training set were used to generate the nomogram. The composite nomogram showed improved prognostic accuracy in the training, validation, and entire cohorts compared with that of TNM stage alone.

Conclusions

In conclusion, our proposed nomogram represents a promising tool for estimating OS in Siewert type II AEG patients after preoperative radiotherapy.

Electronic supplementary material

The online version of this article (10.1245/s10434-019-07237-7) contains supplementary material, which is available to authorized users.

Pathological evaluation of neoadjuvant chemotherapy in advanced gastric cancer

Background

Although pathological evaluation has been considered an effective evaluation method, some problems still exist in practice. Therefore, we explored whether there are more reasonable and practical pathological evaluation criteria for neoadjuvant chemotherapy in patients with advanced gastric cancer. Here, we aim to determine pathological judgment criteria for neoadjuvant chemotherapy in patients with advanced gastric cancer.

Methods

Eighty-seven patients with cT2–4 or cN+ were enrolled in this study. Pathological factors for overall survival (OS) were investigated using univariate and multivariate analyses, and the pathological criteria for neoadjuvant chemotherapy were then determined.

Results

A total of 87 patients underwent 3–4 cycles of neoadjuvant chemotherapy, with 67 (77.0%), 15 (17.2%), and 5 (5.8%) receiving Folfox6, Xelox, and SOX regimens, respectively. All patients showed different levels of graded histological regression (GHR) of the primary tumor, with a ≥ 50% regression rate of 50.6%. The univariate analysis showed that GHR ≥ 50% (p = 0.022), 66.7% (p = 0.013), and 90% (p = 0.028) were significantly correlated with OS. The multivariate analysis demonstrated that ypTNM (II/III) stage was significantly associated with OS compared with ypTNM (0+I) stage [HR = 3.553, 95% CI 1.886–6.617; HR = 3.576, 95% CI 1.908–6.703, respectively] and that the Lauren classification of diffuse type was also an independent risk factor for OS compared with the intestinal type (HR = 3.843, 95% CI 1.443–10.237).

Conclusions

The Lauren classification and ypTNM stage after neoadjuvant chemotherapy are independent prognostic factors in advanced gastric cancer. A GHR ≥ 50%/< 50% can be used as the primary criterion for advanced gastric cancer after neoadjuvant chemotherapy to determine postoperative adjuvant chemotherapy regimens.

ypTNM staging after neoadjuvant chemotherapy in the Chinese gastric cancer population: an evaluation on the prognostic value of the AJCC eighth edition cancer staging system

BACKGROUND

This study aims to evaluate the new ypTNM staging system in Chinese gastric cancer patients.

METHODS

We conducted retrospective survival and regression analyses using a database of gastric cancer patients who underwent neoadjuvant chemotherapy at the Peking University Cancer Hospital and Institute from January 2007 to January 2015.

RESULTS

A total of 473 patients were included in the study with 28 pathological complete response (pCR) cases, 3 ypT0N1 cases, 65 stage I cases, 126 stage II cases, and 251 stage III cases. The pCR cases had similar survival to stage I patients (p > 0.05). The 3-year disease-free survival (DFS) and 5-year overall survival (OS) rates of stage I, II and III patients were significantly different (3-year DFS: 89.0, 75.5, and 39.6%, p < 0.001; 5-year OS: 89.6, 65.5, and 36.5%, p = 0.001). Both ypT and ypN are independent predictors of patient survival, while further log-rank tests showed that the ypN stage is of better prognostic value than ypT. Subgrouping analysis revealed that stage III patients of ypT4b and ypN3 had worse survival compared to the rest of stage III cases (p < 0.001). The c-index values of the ypTNM stage and modified ypTNM stage (stage III divided into IIIa and IIIb) were 0.657 and 0.708, respectively (p < 0.001).

CONCLUSIONS

Our data showed significant differences in survival among gastric cancer patients at different ypTNM stages, indicating its prognostic value in the Chinese population. Further detailed analyses may facilitate the subgrouping of each stage to allow for a more accurate evaluation of disease prognosis in gastric cancer patients.

ypTNM category combined with AJCC tumor regression grade for screening patients with the worst prognosis after neoadjuvant chemoradiation therapy for locally advanced rectal cancer

Background

The purpose of this study was to investigate the value of the postsurgical pathological T and N (ypTN) category combined with the American Joint Committee on Cancer-tumor regression grade (AJCC-TRG) in evaluating the prognosis of neoadjuvant chemoradiation therapy (NeoCRT) for locally advanced rectal cancer (LARC) to screen for a subgroup of patients with the worst prognosis.

Patients and methods

In total, 265 patients with LARC were enrolled in the trial. All patients received NeoCRT. Total mesorectal excision was performed 6-8 weeks after the completion of radiotherapy. The surgical specimens were re-evaluated based on the AJCC-TRG (seventh edition) and the AJCC-tumor-node-metastasis (TNM; seventh edition) systems. We followed up these patients and calculated their overall survival (OS), disease-free survival (DFS), local recurrence-free survival (RFS), and distant metastasis (DM)-free survival (MFS) rates through the Kaplan-Meier analysis. The logrank test was further applied to evaluate the predictive value of the ypTN stage combined with AJCC-TRG for several survival indexes.

Results

The median follow-up period was 65.1 months. The 5-year OS, DFS, RFS, and MFS rates were 79.4%, 68.8%, 94.4%, and 76.5%, respectively. There were significant differences in OS, DFS, and MFS rates among different ypT+AJCC-TRG and ypN+AJCC-TRG subgroups. The 5-year OS, DFS, and MFS rates for ypT3-4+TRG 1 and ypT3-4+TRG2-3 subgroups were 73.9% vs 65.3%, 61.2% vs 52.9%, and 65.0% vs 61.5%, respectively. The 5-year OS, DFS, and MFS rates for ypN1-2+TRG 0-1 and ypN1-2+TRG2-3 subgroups were 64.8% vs 54.1%, 44.9% vs 41.7%, and 61.4% vs 46.3%, respectively.

Conclusion

The ypTNM category combined with the AJCC-TRG can more accurately evaluate the prognosis of patients with LARC and identify the subgroup of patients with the worst prognosis and high risk of developing DM, thereby demonstrating clinical significance in guiding individualized postoperative adjuvant therapy and follow-up for LARC.

Central Lymph Node Metastasis in Gastric Cancer Is Predictive of Survival After Preoperative Therapy

BACKGROUND

It is unclear how preoperative therapy for gastric cancer affects the metastasis rate of lymph nodes (LNs) and whether the location of positive LNs affects survival after preoperative therapy. Therefore, we determined the association between positive central lymph nodes (CnLNs) and disease stage and overall survival (OS).

METHODS

We reviewed a prospectively maintained database to identify patients who had undergone resection of gastric adenocarcinoma at our institution from 2005 to 2015. CnLNs were defined as common hepatic, celiac, and proximal splenic artery LNs (stations no. 8, 9, and 11p). The frequency of CnLN metastases and risk factors affecting OS were examined.

RESULTS

We identified 356 patients. Preoperative therapy was administered to 66% of patients. D2 LN dissection was performed in 80% of patients, and the median number of LNs examined was 25 (IQR, 18-34). In 243 patients (68%), CnLNs had undergone separate pathologic examination; the CnLN-positive rate was 9.1% (22 of 243; station no. 8, 4.5%; no. 9, 2.1%; and no. 11p, 4.8%). CnLN metastasis was associated with shorter 3-year OS in patients with pN2/3 disease (33 vs. 62%; p = 0.004). Among patients who had undergone preoperative therapy, ypT3-4 stage (HR 2.44; p = 0.01) and positive CnLNs (HR 5.44; p < 0.001) were negatively associated with OS by multivariate analysis.

CONCLUSIONS

CnLN metastases are uncommon in gastric cancer and have an adverse effect on OS in patients who have undergone preoperative therapy. Larger multi-institutional studies are needed to determine whether CnLN positivity requires a separate staging category after preoperative therapy.

Neoadjuvant Therapy Improves Outcomes in Locally Advanced Signet-Ring-Cell Containing Esophagogastric Adenocarcinomas

BACKGROUND

Only a few studies have analyzed multimodal treatment concepts in the subgroup of signet-ring-cell containing upper gastrointestinal (GI) cancer. Recent retrospective, multicentric data favor primary resection without neoadjuvant chemotherapy for gastric signet-ring-cell containing carcinomas (SRCs). We compared the outcomes of primarily resected carcinomas with neoadjuvantly treated, locally advanced esophagogastric SRCs.

METHODS

A total of 310 patients with esophagogastric SRC-staged cT3/4/Nany/Many from a prospective unicentric database were included in this study; 192 (61.9%) received neoadjuvant therapy (NEO group) and 118 (38.1%) were primarily resected (RES group).

RESULTS

Overall, 128 (41.3%) patients presented with adenocarcinoma of the esophagogastric junction (AEG) and 182 (58.7%) presented with gastric cancer. Neoadjuvant therapy was significantly associated with resection in curative intent (NEO: 91.1%; RES: 75.4%; P = 0.001), improved (y)pT category (P = 0.035), improved (y)pN category (P < 0.001), and R0 resections (curative intent cohort: 76.0% in NEO vs. 60.7% in RES; P = 0.010), among others, but not with postoperative complications. Overall survival was significantly improved by neoadjuvant treatment {median survival 28.5 months (95% confidence interval [CI] 14.4-39.6) vs. RES: 14.9 months (10.6-17.5); P < 0.001}, as well as in subgroups (AEG and gastric tumors, R0-resected patients, and patients with and without relevant comorbidities). Independent prognostic factors were neoadjuvant therapy (hazard ratio [HR] 0.66; P = 0.023), pT4 category (HR 1.71; P = 0.041), pN2 category (HR 1.86; P = 0.013), pN3 category (HR 2.40; P < 0.001), pM1 category (HR 1.95; P = 0.003), age > 70 years (HR 1.79; P = 0.006), gastric localization (HR 0.69; P = 0.032), American Society of Anesthesiologists classification 3/4 (HR 1.71; P = 0.004), and incomplete resection R1/2 (HR 1.6; P = 0.014).

CONCLUSIONS

Our results demonstrate a survival advantage for advanced-stage esophagogastric SRC patients by neoadjuvant treatment.

Pachymic Acid Sensitizes Gastric Cancer Cells to Radiation Therapy by Upregulating Bax through Hypoxia

We have previously shown that pachymic acid (PA) inhibited tumorigenesis of gastric cancer (GC) cells. However, the exact mechanism underlying the radiation response of GC was still elusive. To evaluate the effects of PA treatment on radiation response of GC cell lines both in vitro and in vivo, a colony formation assay and xenograft mouse model were employed. Changes in Bax and HIF1[Formula: see text] expressions were assessed in GC cells following PA treatment. Luciferase reporter and chromatin immune-precipitation assays were carried out to investigate the regulation of Bax through HIF1[Formula: see text]. Stable HIF1[Formula: see text] knockdown was introduced into GC cells to further study the mechanism underlying PA-enhanced response to radiation both in vitro and in vivo. PA greatly enhanced the sensitivity of GC cells to radiation in vitro and in vivo, upregulated Bax expression and inhibited hypoxia. Bax expression was under hypoxia inhibition, and PA increased Bax expression through repressing HIF1[Formula: see text]. Stable HIF1[Formula: see text] overexpression in GC cells abolished the sensitizing effect of PA on GC cells to radiation both in vitro and in vivo. PA functions as a radiation sensitizing compound in GC. PA treatment induces the expression of pro-apoptotic factor Bax by inhibiting hypoxia/HIF1[Formula: see text], supporting the therapeutic potential of PA in radiation therapy against GC.

Clinicopathological and prognostic significance of high circulating lymphocyte ratio in patients receiving neoadjuvant chemotherapy for advanced gastric cancer

This study was designed to investigate the prognostic value of circulating blood cell counts and subsets for patients with advanced gastric cancer (AGC) treated with neoadjuvant chemotherapy (NAC) and the factors determining pathological complete response (pCR). In 112 patients with AGC, we retrospectively examined the ratios of lymphocyte, monocyte, and neutrophil during and after NAC before surgery, and the percentages of CD3+, CD3+ CD4+, CD3+ CD8+ and CD4+/CD8+ lymphocytes as well. We also investigated their associations with the pCR rate and overall survival (OS). The ratios of lymphocyte taken before and after NAC were significantly greater in forty-four pCR cases than that in sixty-eight non-pCR cases. During NAC, the proportion of lymphocyte and the percentages of CD3+, CD3+ CD4+, and CD3+ CD8+ lymphocytes were dramatically increased in pCR group. The lymphocyte ratio showed an independent association with pCR by multivariate analysis and maintained at a relatively high level in pCR cases. By mean of 31.53% lymphocyte ratio before-NAC and 41.68% after-NAC, cases with high lymphocyte ratio showed significantly better outcome in OS. High circulating lymphocyte ratios, both before and after NAC, are positively associated with pCR and improved OS in advanced gastric cancer, which may be considered as a new prognostic biomarker.

Customization of therapy for gastroesophageal adenocarcinoma patients

Gastroesophageal adenocarcinomas (GEACs) remain a global health problem. These are most often diagnosed at advanced stage and the estimated 5-year relative survival rate is about 5%. Although cure is not possible for patients with advanced GEAC, systemic therapy (chemotherapy or biochemotherapy) can palliate symptoms, improve survival and provide a better quality of life. One of the most promising options for some patients with advanced stage GEAC is immunotherapy, which can result in durable responses. Numerous phase III trials evaluating targeted therapies in different lines are ongoing and it is hoped that better biomarkers will emerge to identify patients who can benefit from targeted agents and immunotherapy in the future. Surgery remains as the corner stone for localized GEAC and adjunctive therapies can increase the survival rates by about 10%. The high toxicity and low completion rates of adjuvant therapy led to the strategies of preoperative treatment. With the results of ongoing pre-operative therapy trials we will be able to determine the optimal adjunctive approach for resectable GEAC.

Correlation of pathological complete response with survival after neoadjuvant chemotherapy in gastric or gastroesophageal junction cancer treated with radical surgery: A meta-analysis

Background

Neoadjuvant chemotherapy before radical gastrectomy is preferred for locally advanced gastric cancer. To avoid the problematic use of pTNM for patients after neoadjuvant chemotherapy, the Union for International Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC) gastric cancer TNM staging system (8th edition) added ypTNM for the first time. But patients achieving pathological complete response were not covered by the new ypTNM staging system. To investigate whether pathological complete response is associated with better outcome in gastric cancer, as was reported in rectal, breast and bladder cancer.

Methods

We systematically searched the databases of PubMed, EMBASE, Web of Science and Cochrane Collaboration’s Central register of controlled trials from January 1988 to April 2015 for publications which reported outcomes of patients with and without pathological complete response (pCR) (pT0N0M0) to investigate whether pCR after neoadjuvant chemotherapy in gastric or gastroesophageal junction (GEJ) treated with radical surgery is associated with better survival. The primary outcome was overall survival (OS). The secondary outcome was disease-free survival (DFS). Both were measured with a relative risk (RR). A meta-analysis was performed using the fixed effects model. Forest plots and the Q test was used to evaluate overall heterogeneity for OS and DFS.

Results

A total of seven trials, 1143 patients were included and analyzed after neoadjuvant chemotherapy and radical surgery with no other preoperative treatment. The average rate of pCR was 6.74% (range: 3%-15%). The RR of patients who achieved pCR in the primary tumor and lymph nodes is 0.5 (95% confidence interval [CI], 0.25–0.98; p = 0.04), 0.34 (95% CI, 0.21–0.55; p<0.0001) and 0.44 (95% CI, 0.30–0.63; p<0.0001) for one-year-OS, three-year-OS and five-year-OS, respectively. The summary RR for three-year-DFS was 0.43 (95% CI, 0.25–0.72; p = 0.002).

Conclusion

Patients with resectable gastric or GEJ cancer who achieved pCR after neoadjuvant chemotherapy can gain a better outcome than patients without pCR.

Evaluation of the American Joint Committee on Cancer 8th edition staging system for gastric cancer patients after preoperative therapy

BACKGROUND

The American Joint Committee on Cancer (AJCC) recently released its 8th edition staging system, which created a separate staging system for gastric cancer patients who have undergone preoperative therapy (ypStage). The objective of this retrospective study was to apply the new ypStage to patients who have undergone preoperative therapy and potentially curative gastrectomy.

METHODS

We collected data from a prospectively maintained institutional database of gastric cancer patients who underwent potentially curative gastrectomy after preoperative therapy (1995-2015). Kaplan-Meier survival estimations and log-rank tests were performed to compare survival. Univariable and multivariable analyses were performed to determine risk factors for overall survival.

RESULTS

A total of 354 patients met our criteria. Most patients completed planned preoperative therapy (94%; 332/354) and received chemoradiation therapy (75%; 265/354). Although clinical stage (cStage) provided a poor discrimination of survival, postneoadjuvant pathological stage (ypStage) identified significant variation in survival (p < 0.001). Multivariable analysis showed the following factors were associated with survival after adjustment for ypStage: Asian race (HR 0.52; p = 0.028), linitis plastica (HR 1.66; p = 0.037), and R1 resection (HR 1.91; p = 0.016). Survival was not longer in ypT0N0 patients than in ypStage I patients (HR 1.29; p = 0.377).

CONCLUSIONS

The AJCC 8th edition staging system for gastric cancer demonstrated reasonable survival prediction by ypStage, but not cStage, in patients who had undergone preoperative therapy. ypT0N0 patients, although not defined in the 8th edition, may be considered for inclusion in the ypStage I group.

A novel grade-lymph node ratio model predicts the prognosis of the advanced gastric cancer patients after neoadjuvant radiotherapy

Although local advanced gastric cancer (AGC) could benefit from neoadjuvant radiotherapy (NRT), there are few studies evaluating patients survival after NRT. In current study, we aimed to investigate the value of prognostic factors in AGC patients after NRT and to evaluate whether post-therapy pathological characteristics were predictive factors in these patients. We retrospectively analyzed AGC patients who underwent NRT from Surveillance, Epidemiology, and End Results (SEER) Database. The patients clinical and post-therapy pathological characteristics were analyzed. The best cutoff points for continuous variables were identified by X-tile. The discrimination of risk factors were compared by receiver operating characteristic (ROC) curve. As a result, 1,429 AGC patients were included into this study. In the multivariate analysis, the lymph nodes status and histology grade were significant risk factors for DSS (disease special survival). Then, we propose a novel Grade-lymph node Ratio (G-R) staging system for the AGC patients survival prognosis. Clearly, the new G-R staging system has a more-accurate 3-year and 5-year DSS prediction than the AJCC staging system (p = 0.001, 0.007, respectively). In conclusions, the current large, general population-based study demonstrated that the G-R staging system resulting in more-accurate DSS prediction. It could be regarded as a reliable classification for AGC patients after NRT in future.