The newly proposed clinical and post-neoadjuvant treatment staging classifications for gastric adenocarcinoma for the American Joint Committee on Cancer (AJCC) staging

Prognostic value of a modified pathological staging system for gastric cancer based on the number of retrieved lymph nodes and metastatic lymph node ratio

Aim

The prognosis for gastric cancer (GC) remains grim, underscoring the importance of accurate staging and treatment. Given the potential benefits of using lymph node ratio (LNR) for improved prognostication and treatment planning, it is critical to incorporate examined lymph nodes (ELN) count in an integrated GC staging system.

Methods

Patients data from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015 was utilized as training set. The Mantel-Cox survival test was used to calculate chi-square values for 40 LNR segments with a 0.025 interval, defining a novel LNR-based N (rN) classification based on the cutoff points. A revised AJCC (rAJCC) staging system was established by replacing the 8th AJCC N staging with a rN classification. The relationship between the ELN count and prognosis or positive lymph node detection was conducted by using multivariable models. The series of the odds ratios and hazard ratios were fitted with a locally weighted scatterplot smoothing (LOWESS) smoother, and the structural break points were determined by Chow test to clarify an optimal minimum ELN count. The integrated GC staging system incorporated both rAJCC system and the ideal ELN count. Discriminatory ability and prognostic homogeneity of the rAJCC and integrated staging system was compared with AJCC staging system in the SEER validation set (2016-2017), the Cancer Genome Atlas Program (TCGA) database, and the Third Affiliated Hospital of Sun Yat-sen University database.

Results

The current study found that LNR and ELN count are both significantly associated with the prognosis of GC patients (HR = 0.98, p < 0.001 and HR = 2.51, p < 0.001). Four peaks of the chi-square value were identified as LNR cut-off points at 0.025, 0.175, 0.45 and 0.6 to define a novel rN stage. In comparison to the 8th AJCC staging system, the rAJCC staging system demonstrated significant prognostic advantages and discriminatory ability in the training set (5-Y OS AUC: 71.7 vs. 73.0; AIC: 57,290.7 vs. 57,054.9). The superiority of the rAJCC staging system was confirmed in all validation sets. Using a LOWESS smoother and Chow test, a threshold ELN count of 30 was determined to maximum improvement in the prognosis of node-negative patients without downgrading due to potential metastasis, while also maximizing the detection efficiency of at least one involved lymph node. The integrated staging system, combining the refined rAJCC classification with an optimized ELN count threshold, has demonstrated superior discriminatory performance compared to the standalone rAJCC or the traditional AJCC system.

Conclusion

The development of a novel GC staging system, which integrated the LNR-based N classification and the minimum ELN count, has exhibited superior prognostic accuracy, holding promise as a valuable asset in the clinical management of GC. However, it is crucial to recognize the limitations from the retrospective database, which should be addressed in subsequent analyses.

Survival Outcomes in Patients with Resectable Gastric Cancer Treated with Total Neoadjuvant Therapy

BACKGROUND

Perioperative chemotherapy has become the standard of care for locally advanced gastric cancer. Total neoadjuvant therapy (TNT), including both chemotherapy and chemoradiation, is utilized in other gastrointestinal malignancies. We determined survival in a contemporary cohort of gastric cancer patients treated with TNT.

METHODS

Using a prospective institutional database, patients diagnosed with cT2-4 or cN+ gastric adenocarcinoma (January 2012 to June 2022) who underwent staging laparoscopy, received TNT, and underwent gastrectomy were identified. Overall survival (OS) and disease-specific survival (DSS) were determined using standard statistical methods.

RESULTS

The study included 203 patients. The most common TNT sequence was induction chemotherapy followed by chemoradiation (n = 186 [91.6%]). A total of 195 (96.1%) patients completed planned neoadjuvant treatments. Surgery included total gastrectomy in 108 (53.2%), extended (D1+/D2) lymphadenectomy in 193 (95.1%), and adjacent organ resection in 19 (9.4%) patients. Pathologic complete response (pCR) was achieved in 32 (15.8%) patients. The 5-year OS rate was 65.2% (95% confidence interval [CI] 57.8-73.5%), and the 5-year DSS rate was 70.8% (95% CI 63.6-78.9%) in the study cohort. Among patients with pCR, the 5-year OS rate was 89.1% (95% CI 78.1-100.0%), and the 5-year DSS rate was 96.9% (95% CI 91-100%). Posttreatment pathologic N and M stages were the strongest prognostic indicators associated with both OS and DSS.

CONCLUSIONS

Total neoadjuvant therapy for resectable gastric cancer is associated with a high rate of treatment completion and promising survival outcomes. Prospective comparisons with perioperative treatment are needed to identify patients most likely to benefit from TNT.

Perioperative chemotherapy with nivolumab for HER2-negative locally advanced gastric cancer: a case series

BACKGROUND

Nivolumab with chemotherapy has been transformative for metastatic gastric cancer (GC). The potential of this regimen for local tumor control could be utilized for perioperative chemotherapy in locally advanced GC with bulky tumors or lymph node metastasis involving other organs.

CASE PRESENTATION

Five patients with HER2-negative advanced GC were treated with nivolumab and oxaliplatin-based chemotherapy. All patients presented with clinical stage III or IVA GC with tumors in contact with either the pancreas or liver. Following chemotherapy, all tumors demonstrated shrinkage, allowing successful radical gastrectomies including four minimally invasive approach without postoperative complications. Four patients avoided combined resection of other organs.

CONCLUSIONS

Perioperative chemotherapy with nivolumab was effective for local disease control in this case series. This regimen could be a promising treatment approach for locally advanced GC; however, its survival benefits should be evaluated in clinical trials.

Postoperative body weight change and its influencing factors in patients with gastric cancer

BACKGROUND

The high incidence and mortality of gastric cancer (GC) pose a significant threat to human life and health, and it has become an important public health challenge in China. Body weight loss is a common complication after surgical treatment in patients with GC and is associated with poor prognosis and GC recurrence. However, current attention to postoperative weight change in GC patients remains insufficient, and the descriptions of postoperative weight change and its influencing factors are also different.

AIM

To investigate body weight changes in patients with GC within 6 mo after gastrectomy and identify factors that influence dynamic body weight changes.

METHODS

We conducted a prospective longitudinal study of 121 patients with GC and collected data before (T0) and 1 (T1), 3 (T2), and 6 (T3) mo after gastrectomy using a general data questionnaire, psychological distress thermometer, and body weight measurements. The general estimation equation (GEE) was used to analyze the dynamic trends of body weight changes and factors that influence body weight changes in patients with GC within 6 mo of gastrectomy.

RESULTS

The median weight loss at T1, T2, and T3 was 7.29% (2.84%, 9.40%), 11.11% (7.64%, 14.91%), and 14.75% (8.80%, 19.84%), respectively. The GEE results showed that preoperative body mass index (BMI), significant psychological distress, religious beliefs, and sex were risk factors for weight loss in patients with GC within 6 mo after gastrectomy (P < 0.05). Compared with preoperative low-weight patients, preoperative obese patients were more likely to have weight loss (β = 14.685, P < 0.001). Furthermore, patients with significant psychological distress were more likely to lose weight than those without (β = 2.490, P < 0.001), and religious patients were less likely to lose weight 6 mo after gastrectomy than those without religious beliefs (β = -6.844, P = 0.001). Compared to female patients, male patients were more likely to experience weight loss 6 mo after gastrectomy (β = 4.262, P = 0.038).

CONCLUSION

Male patients with GC with high preoperative BMI, significant psychological distress, and no religious beliefs are more likely to lose weight after gastrectomy.

Comprehensive multi-omics analysis of resectable locally advanced gastric cancer: Assessing response to neoadjuvant camrelizumab and chemotherapy in a single-center, open-label, single-arm phase II trial

BACKGROUND

The current standard of care for locally advanced gastric cancer (GC) involves neoadjuvant chemotherapy followed by radical surgery. Recently, neoadjuvant treatment for this condition has involved the exploration of immunotherapy plus chemotherapy as a potential approach. However, the efficacy remains uncertain.

METHODS

A single-arm, phase 2 study was conducted to evaluate the efficacy and tolerability of neoadjuvant camrelizumab combined with mFOLFOX6 and identify potential biomarkers of response through multi-omics analysis in patients with resectable locally advanced GC. The primary endpoint was the pathological complete response (pCR) rate. Secondary endpoints included the R0 rate, near pCR rate, progression-free survival (PFS), disease-free survival (DFS), and overall survival (OS). Multi-omics analysis was assessed by whole-exome sequencing, transcriptome sequencing, and multiplex immunofluorescence (mIF) using biopsies pre- and post-neoadjuvant therapy.

RESULTS

This study involved 60 patients, of which 55 underwent gastrectomy. Among these, five (9.1%) attained a pathological complete response (pCR), and 11 (20.0%) reached near pCR. No unexpected treatment-emergent adverse events or perioperative mortality were observed, and the regimen presented a manageable safety profile. Molecular changes identified through multi-omics analysis correlated with treatment response, highlighting associations between HER2-positive and CTNNB1 mutations with treatment sensitivity and a favourable prognosis. This finding was further supported by immune cell infiltration analysis and mIF. Expression data uncovered a risk model with four genes (RALYL, SCGN, CCKBR, NTS) linked to poor response. Additionally, post-treatment infiltration of CD8+ T lymphocytes positively correlates with pathological response.

CONCLUSION

The findings suggest the combination of PD-1-inhibitor and mFOLFOX6 showed efficacy and acceptable toxicity for locally advanced GC. Extended follow-up is required to determine the duration of the response. This study lays essential groundwork for developing precise neoadjuvant regimens.

Neoadjuvant docetaxel, oxaliplatin plus capecitabine versus oxaliplatin plus capecitabine for patients with locally advanced gastric adenocarcinoma: long-term results of a phase III randomized controlled trial

BACKGROUND

Neoadjuvant chemotherapy with docetaxel, oxaliplatin, and capecitabine (DOX regimen) is rarely used in Eastern countries and its efficacy and safety in advanced gastric cancer have not been reported. In this open-label, randomized, controlled trial, the authors aimed to assess the clinical efficacy of neoadjuvant chemotherapy using the DOX and oxaliplatin plus capecitabine (XELOX) regimens, in comparison to surgery alone.

MATERIALS AND METHODS

Three hundred patients younger than 60 years with potentially resectable advanced gastric cancer (cT3-4, Nany, M0) were enrolled in this randomized controlled clinical trial between November 2014 and June 2018. The primary endpoint of the study was the pathological complete response (pCR) rate. Secondary endpoints included 3-year overall survival (OS), 3-year disease-free survival.

RESULTS

In total, 280 patients (93 in the DOX group, 92 in the XELOX group, and 95 in the surgery group) were included in the per-protocol analysis. The DOX group demonstrated a significantly higher pCR rate compared to the XELOX group (16.1 vs. 4.3%, P =0.008). For patients with intestinal type, the DOX group exhibited significantly higher rates of both pCR and major pathological response compared to the XELOX group ( P =0.007, P <0.001). The 3-year OS rates of the DOX group, the XELOX group and the surgery group were 56.9, 44.6, and 34.7%, respectively. The 3-year disease-free survival rates were 45.2, 40.2, and 28.4%, respectively. The neoadjuvant DOX regimen demonstrated a significant improvement in the 3-year OS of patients compared to the neoadjuvant XELOX regimen ( P =0.037).

CONCLUSION

The neoadjuvant DOX regimen has shown the potential to increase the pCR rate and improve the prognosis of patients with advanced gastric cancer who are under 60 years old.

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.

Neoadjuvant PD-1 Inhibitor Plus Apatinib and Chemotherapy Versus Apatinib Plus Chemotherapy in Treating Patients With Locally Advanced Gastric Cancer: A Prospective, Cohort Study

PURPOSE

This study aimed to evaluate the efficacy and safety of neoadjuvant programmed cell death-1 (PD-1) inhibitors plus apatinib and chemotherapy (PAC) in patients with locally advanced gastric cancer (LAGC).

MATERIALS AND METHODS

Seventy-three patients with resectable LAGC were enrolled and named the PAC group (n=39) or apatinib plus chemotherapy (AC) group (n=34) based on the treatment they chose. Neoadjuvant therapy was administered in a 21-day cycle for 3 consecutive cycles, after which surgery was performed.

RESULTS

The PAC group exhibited a higher objective response rate than the AC group (74.4% vs. 58.8%, P=0.159). Moreover, the PAC group showed a numerically better response profile than the AC group (P=0.081). Strikingly, progression-free survival (PFS) (P=0.019) and overall survival (OS) (P=0.049) were prolonged, whereas disease-free survival (DFS) tended to be longer in the PAC group than in the AC group (P=0.056). Briefly, the 3-year PFS, DFS, and OS rates were 76.1%, 76.1%, and 86.7% in the PAC group and 46.9%, 49.9%, and 70.3% in the AC group, respectively. Furthermore, PAC (vs. AC) treatment (hazard ratio=0.286, P=0.034) was independently associated with prolonged PFS in multivariate Cox regression analyses. The incidence of adverse events did not differ between the two groups (all P>0.05), where leukopenia, anemia, hypertension, and other adverse events were commonly observed in the PAC group.

CONCLUSIONS

Neoadjuvant PAC therapy may achieve a preferable pathological response, delayed progression, and prolonged survival compared to AC therapy with a similar safety profile in patients with LAGC; however, further validation is warranted.

ypTNM staging is a potentially useful prognostic stratification tool in patients with advanced gastric cancer after preoperative chemotherapy

PURPOSE

Although the usefulness of the ypStage in neoadjuvant chemotherapy for advanced gastric cancer (GC) has been reported, whether or not the ypStage is applicable to all GC patients who receive preoperative chemotherapy, including conversion surgery cases, is unclear. Therefore, this retrospective study evaluated the value of the ypTNM staging system in all advanced GC patients who received chemotherapy prior to gastrectomy.

METHODS

A total of 66 patients who underwent chemotherapy prior to gastrectomy for advanced GC at Chiba University Hospital from January 2008 to December 2020 were enrolled in the current study. The prognostic impact of the ypStage on the overall survival (OS) and relapse-free survival (RFS) were examined via univariate and multivariate analyses.

RESULTS

The 5-year OS rates for ypStage I, II, III, and IV were 87.5%, 64.7%, 52.9%, and 28.6%, respectively, while the 5-year RFS rates were 81.3%, 57.4%, 44.4%, and 28.6%, respectively. The univariate analysis revealed that the ypStage was significantly correlated with the OS (p = 0.037) and the ypT status and ypStage showed a significant correlation with the RFS (p = 0.043 and p = 0.021, respectively). The multivariate analysis demonstrated that only the ypStage was an independent prognostic factor for the OS and RFS (p = 0.024 and p = 0.018, respectively).

CONCLUSION

The ypTNM stage may be a useful tool for the risk stratification of all advanced GC patients treated with chemotherapy followed by gastrectomy, including not only neoadjuvant but also conversion surgery cases.

The safety and efficacy of carbon nanoparticle suspension injection versus indocyanine green tracer-guided lymph node dissection during radical gastrectomy (FUTURE-01): A single-center randomized controlled trial protocol

Background

The use of lymph node (LN) tracers can help obtain a complete dissection of the lymph nodes and increase the detection rate of LNs and metastatic LNs. Carbon nanoparticle suspension injection (CNSI) and indocyanine green (ICG) have been widely used in radical gastrectomy in recent years. Nevertheless, the comparison of their clinical effects has not been studied.

Method/design

The FUTURE-01 trial will be the first randomized, open-label, single-center trial to compare CNSI and ICG. The study started in 2021 and enrolled 96 patients according to a prior sample size calculation. The primary outcome is the number of LNs retrieved. The secondary outcomes are LN staining rate, LN metastasis rate, stained LN metastasis rate, perioperative recovery and survival.

Conclusion

By comparing the safety and efficacy of CNSI and ICG tracer-guided LN dissection in patients with gastric cancer, we can determine the most appropriate LN tracer at present. With the help of LN tracers, the operation is simplified, and the prognosis of these patients is improved. Our study is a prospective exploration of the safety, efficacy, and prognosis of CNSI and ICG.

Clinical trial registration

https://clinicaltrials.gov/ct2/show/NCT05229874?cond=NCT05229874&draw=2&rank=1, identifier NCT05229874.

Weight Loss During Neoadjuvant Therapy Is Associated With Poor Response Among the Patients With Gastrointestinal Cancer: A Propensity Score Matching Analysis

PURPOSE

The aim of the current study was to identify the relationship between body composition changes during neoadjuvant therapy (NAT) and the treatment efficiency of NAT in gastrointestinal cancer (GC) patients.

METHODS

From January 2015 to July 2020, 277 GC patients treated with NAT had included for retrospective analysis. The body mass index (BMI) and computed tomography (CT) imaging before and after NAT were recorded. The BMI change optimal cut-off value were calculated by ROC curve. Balancing essential characteristic variables using propensity score matching (PSM) method. Exploring the association between BMI changes and tumor response to NAT using logistic regression analysis. The survival outcome of matched patients between different BMI change groups was compared.

RESULTS

A cutoff point of BMI change >2% during NAT was defined as BMI loss. Among the 277 patients, 110 (39.7%) patients showed BMI change with a loss after NAT. In total, 71 pairs of patients were selected for further analysis. The median follow-up time was 22 months (range 3 to 63 months). Univariate and multivariate logistic regression analyses in matched cohort showed that BMI change was a prognostic factor for tumor response after NAT in GC patients (odds ratio (OR), .471; 95% confidence interval (CI), .233-.953; P = .036). In addition, patients who experienced BMI loss after NAT showed worse overall survival than those who had BMI gain or stable.

CONCLUSION

BMI loss during NAT probably may has negative effects on NAT efficiency and survival for gastrointestinal cancer patients. It is necessary to monitor and maintain weight for patients during treatment.

Tracers in Gastric Cancer Surgery

The treatment of gastric cancer mainly depends on radical gastrectomy. Determination of appropriate surgical margins and adequate lymph node (LN) resection are two major surgical steps that directly correlate with prognosis in gastric cancer. Due to the expanding use of minimally invasive procedures, it is no longer possible to locate tumors and LNs through touch. As an alternative, tracers have begun to enter the field due to their capacities for intraoperative visualization. Herein, we summarize the application of contemporary tracers in gastric cancer surgery, including isosulfan blue, methylene blue, patent blue, indocyanine green, carbon particles, and radioactive tracers. Their mechanisms, administration methods, detection efficiency, and challenges, as well as perspectives on them, are also outlined.

Evaluation of the 8th Edition AJCC Staging System for the Clinical Staging of Pancreatic Cancer

The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for pancreatic cancer (PC) has been validated for pathological staging; however, its significance for clinical staging remains uncertain. We validated the prognostic performance and suitability of the current staging system for the clinical staging of PC. We identified 1043 patients from our PC registry who were staged by imaging according to the 8th edition staging system and conducted analysis, including overall survival (OS) comparison. Gradual prognostic stratification according to stage hierarchy yielded significant OS differences between stage groups, except between stage I and II (p = 0.193). A substage comparison revealed no survival differences between IB (T2N0) and IIA (T3N0), which were divided by the T3 criterion only (p = 0.278). A higher N stage had significantly shorter OS than a lower N stage (all pairwise p < 0.05). However, among the 150 patients who received upfront surgery, the pathological stage was more advanced than the clinical stage in 86 (57.3%), mostly due to a false-negative cN0 (70.9%). Our results suggest that the new definition of T3 and the number-based N criteria in the 8th edition AJCC staging system may be not adequate for clinical staging. Establishing separate criteria more suitable for clinical staging should be considered.

Neoadjuvant PD-1 inhibitor and apatinib combined with S-1 plus oxaliplatin for locally advanced gastric cancer patients: a multicentered, prospective, cohort study

PURPOSE

Programmed cell death protein 1 (PD-1) inhibitor and apatinib have been utilized in metastatic gastric cancer patients. The current study aimed to further investigate the efficacy and safety of neoadjuvant S-1 plus oxaliplatin combined with PD-1 inhibitor and apatinib (SOXPA) in locally advanced gastric cancer (LAGC) patients.

METHODS

This two-centered, prospective, cohort study analyzed 30 resectable LAGC patients receiving SOXPA as neoadjuvant therapy.

RESULTS

Two (6.7%), 18 (60.0%), and 10 (33.3%) patients achieved complete response (CR), partial response (PR), and stable disease (SD), separately. The objective response rate (ORR) and disease control rate (DCR) were 66.7% and 100.0%, respectively. The R0 resection rate was 93.3%. Beyond that, 6 (20.0%), 18 (60.0%), and 6 (20.0%) patients achieved grade 1, 2, and 3 pathological responses. The pathological complete response (pCR) rate was 20%. The 1-year and 2-year disease-free survival (DFS) rates were 96.6% and 77.7% respectively; meanwhile, the 1-year and 2-year overall survival (OS) rates were 96.6% and 90.1%, separately. What's more, better clinical response (P = 0.046); achievement of ORR (P = 0.014), and better pathological response (P = 0.020) were correlated with longer DFS. Besides, ORR achievement was linked with longer OS (P = 0.040). Most adverse events were relatively mild and manageable. Grade 3 adverse events included leukopenia, anemia, neutropenia, fatigue, hand-foot syndrome, nausea and vomiting. No grade 4 adverse events were witnessed.

CONCLUSION

SOXPA as neoadjuvant therapy achieves a satisfying clinical response, pathological response, survival profile, and tolerable safety in LAGC patients.

Revisiting the 8th AJCC system for gastric cancer: A review on validations, nomograms, lymph nodes impact, and proposed modifications

Gastric cancer is the fifth most frequently diagnosed cancer worldwide, behind breast, lung, colorectal, and prostate cancers. In gastric cancer, multimodality treatment shows prospective benefits and also improves survival. Surgery, however, is the mainstay of curative treatment. The staging of gastric cancer patients is critical for harmonization of care. Accurate stages assure that informed clinical decisions are timely made. The American Joint Committee on Cancer (AJCC) staging system is the most widely applied system in to determine the disease's prognosis and survival prediction. The recently adopted 8th AJCC TNM staging system has been revised to enhance its survival predictive power. Subsequent studies have established the validity of the current edition, demonstrating improved stage stratification, discriminatory power, and survival prediction. However, other studies have cast doubt on the superiority of the new edition. Innovations aimed at further improving its prognosis have resulted in developing of novel models. Advances in our understanding of the tumor microenvironment and molecular categorization of cancer have resulted in proposals for their inclusion in TNM staging as potential complementary factors that enhance survival prediction and prognostic assessment ability. The purpose of this study is to conduct a review of the published literature regarding the validity of the 8th AJCC TNM staging system, proposed modifications, and nomograms.

•

The 8th AJCC is valid in prognostic stratification of gastric cancer, however, revisions are still required.

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The yPT staging requires some modifications and inclusion of stages that currently don't exist in the 8th AJCC.

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High lymph nodes count and anatomical localization improve the prediction ability of the current AJCC.

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Nomograms comprising of individual prognostic factors are crucial to the current AJCC.

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Molecular markers positively influence survival prediction of gastric cancer.

Role of carbon nanotracers in lymph node dissection of advanced gastric cancer and the selection of preoperative labeling time

BACKGROUND

The incidence of gastric cancer is high. The number of dissected lymph nodes was an independent factor affecting prognosis. Although preoperative labeling is helpful in lymph nodes resection, there are no guidelines for when to perform preoperative labeling.

AIM

To investigate the role of nanocarbon in lymph node dissection during gastrectomy, and to discuss the relationship between the timing of preoperative injection of carbon nanoparticles and the extent of lymph node dissection.

METHODS

A prospective analysis was performed on the clinical data of 307 patients with advanced gastric cancer who underwent laparoscopic surgery in the General Surgery Department of Weifang People’s Hospital between June 2018 and February 2021. The patients were randomly divided into experimental group and control group based on whether they received preoperative nanocarbon injection or not. The experimental group was divided into different groups according to the preoperative labeling time. The number of dissected lymph nodes and the number of lymph nodes with black staining were compared in each group after surgery, and the role of nanocarbon in the number of dissected lymph nodes, pathological staging, and the relationship with prognosis were discussed.

RESULTS

The average number of dissected lymph nodes in the experimental group was higher than that in the control group. In the experimental group, the number of lymph node dissections and number of black-staining lymph nodes in the nanocarbon-labeling group at 2 d and 1 d before surgery were higher than in the labeling group on the day before surgery (P < 0.05).

CONCLUSION

Preoperative nanocarbon labeling can safely and effectively guide lymph node dissection. To improve the detection rate of lymph nodes is conducive to subsequent comprehensive anti-tumor therapy.

Computed Tomography Features and Clinical Prognostic Characteristics of Hepatoid Adenocarcinoma of the Stomach

PURPOSE

Hepatoid adenocarcinoma of the stomach (HAS) is a highly malignant and aggressive tumor. The purpose of this study was to describe the clinical, computed tomography (CT), and prognostic features of HAS to increase the awareness of this entity and determine its distinguishing features from non-HAS tumors.

METHODS

The CT features and clinical data of 47 patients in our hospital with pathologically documented HAS were retrospectively analyzed, and the relevant differences between pure HAS (pHAS) and mixed HAS (mHAS) were determined. In addition, 141 patients with non-HAS tumors in the same T stage in the same period were selected as the control group. The data were compared between the two groups, and factors affecting the prognosis of HAS were analyzed. In addition, we included 9 patients with HAS and 27 patients with non-HAS tumors from another center for external validation.

RESULTS

The patients in the HAS group were predominantly men (n = 33), and the tumor location was mostly the cardia or fundus (n = 27). Between the HAS and non-HAS groups, there were observed differences in terms of: sex, serum alpha-fetoprotein (AFP), carbohydrate antigen (CA)-125, and CA-724 levels; longest tumor diameter; degree of differentiation; vascular invasion; N stage, M stage, and tumor-node-metastasis (TNM) stage; thickest tumor diameter; plain CT attenuation; arterial-phase CT attenuation; CT attenuation between the venous and arterial phases; enhancement modes; and degrees of enhancement (all P < 0.05). In the data from another center for external validation, there were observed differences in terms of: age, degree of differentiation, vascular invasion, thickest tumor diameter, the ratio of arterial CT attenuation to CT attenuation of the abdominal aorta at the same level (RA), CT attenuation difference between the venous phase and arterial phase (HUv-a) (all P < 0.05). The results of the multivariate analysis revealed that the independent factors for differentiation were serum AFP level (P = 0.001), M stage (P = 0.038), and tumor enhancement on CT (P = 0.014). Among patients in the HAS group, 72.34% had pHAS and 27.66% had mHAS. The thickest tumor diameter and the longest short diameter of the metastatic lymph nodes of the mHAS group were on average 6.39 cm and 1.45 cm, respectively, which were larger than those in the pHAS group. The median progression-free survival time was 18.25 months in the HAS group, which was shorter than that in the non-HAS group (72.96 months; P = 0.001). The median overall survival time in the HAS group was 24.80 months, which was shorter than that in the non-HAS group (67.96 months; P = 0.001). The factors affecting the prognosis of HAS were M stage (P = 0.001), overall TNM stage (P = 0.048), presence of vascular cancer emboli (P = 0.040), and pHAS type (P = 0.046). Multifactorial analysis revealed that M stage (P = 0.027) and pHAS type (P = 0.009) were independent risk factors affecting the prognosis of HAS.

CONCLUSION

Although HAS is a rare clinical entity, it should be considered in the differential diagnosis of gastric tumors. Patients with HAS often have advanced-stage disease at presentation and a worse prognosis than patients with non-HAS tumors. CT findings, combined with laboratory results, can support the diagnosis of HAS. However, the final diagnosis needs to be confirmed with a histopathologic examination. If the postoperative pathologic findings reveal the mHAS type, a rapid clinical intervention and a detailed follow-up with CT are essential.

Lymph node ratio-based the ypTNrM staging system for gastric cancer after neoadjuvant therapy: a large population-based study

PURPOSES

The lymph node ratio (LNR) has been considered a better prognostic factor than traditional N staging in patients with gastric cancer (GC), but its accuracy is unclear for those who receive neoadjuvant therapy (NAT). We aimed to compare the node ratio (Nr) staging with the ypN staging and to thereby develop a modified staging system incorporating Nr staging.

METHODS

A total of 1791 patients who underwent gastrectomy after NAT in the Surveillance, Epidemiology, and End Results database were retrospectively analyzed. ypTNrM staging was established based on the overall survival (OS).

RESULTS

The Nr staging was generated using 0.2 and 0.5 as the cutoff values of LNR and represented patients with more homogeneous OS compared with ypN staging. The 5-year OS rates for ypTNrM stages IA, IB, II, IIIA, and IIIB were 70.2%, 54.2%, 36.0%, 21.2%, and 6.6%, respectively, compared with 58.8%, 39.1%, and 21.6% for ypTNM stages I, II, and III, respectively. Compared with the ypTNM staging system, the ypTNrM staging system had a lower misclassification rate (3.0% vs. 50.9%) and better prognostic predictive power (C-index: 0.645 vs. 0.589, P < 0.001).

CONCLUSIONS

The ypTNrM staging system incorporating Nr staging may provide a more accurate assessment in the clinical decision-making process for GC after NAT.

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.

Revised points and disputed matters in the eighth edition of the TNM staging system for gastric cancer

The American Joint Committee on Cancer and the Union for International Cancer Control have now released the eighth edition of the cancer staging system, which incorporates some major revisions concerning gastric cancer. First, grouping of pathological stages has been revised in accordance with a proposal from the International Gastric Cancer Association. That revision was based on analysis of survival of more than 25 000 patients worldwide who had undergone curative gastrectomy without neoadjuvant therapy. Stratification of survival in Stage III subgroups has been improved by subdividing N3 into N3a and N3b. Second, a simplified grouping of clinical stages that differs completely from grouping of pathological stages has been proposed. Pre-treatment depth of tumour invasion is now categorized as T1/T2, T3/T4a or T4b, and lymph node status is simply categorized as N0 or N+. Additionally, a 'yp-stage' for specimens resected after neoadjuvant therapy has been newly proposed. These clinical and post-neoadjuvant stages were considered useful now that neoadjuvant chemotherapy is increasingly being administered to patients with potentially resectable gastric cancer. Third, staging of oesophagogastric junction tumours has been modified; Siewert type 3 tumours are now classified as gastric tumours and are staged according to the gastric, rather than the oesophageal, system. More appropriate staging of gastric cancers treated with neoadjuvant therapy, and/or new staging systems incorporating variables other than T/N/M, such as biological or genomic markers, are likely future developments.

Short-term outcomes of laparoscopic versus open total gastrectomy after neoadjuvant chemotherapy: a cohort study using the propensity score matching method

Background

Until now, little is known about the benefit of laparoscopic total gastrectomy (LTG) after neoadjuvant chemotherapy (NACT). This study was designed to compare the safety and efficacy of the LTG versus the open total gastrectomy (OTG) approach after NACT treatment in patients with advanced gastric cancer (AGC).

Methods

This study involved a cohort of 145 patients with AGC who underwent total gastrectomy after NACT at our centre between April 2013 and August 2018 including 24 cases of LTG and 121 OTG. The baseline characteristics were matched based on 1:2 balanced propensity score-matching method.

Results

Sixty-nine marched cases were finally analysed (23 LTG vs. 46 OTG). All patients underwent R0 resection. Compared to the OTG group, the LTG group had a longer surgery duration (P<0.001), but a shorter incision length (P<0.001) and less intravenous patient-controlled analgesia (IV-PCA) time after surgery (P=0.027). No statistical differences were observed in terms of blood loss, retrieved lymph nodes (LNs), resection margin, length of stay, postoperative pain intensity, and complications (P>0.05).

Conclusions

LTG had comparable safety and histological findings to OTG after NACT in the perioperative period; however, LTG is less invasive and patients can benefit from less IV-PCA use. Further research is needed to investigate long-term effects.

Keywords

Gastric cancer (GC); neoadjuvant chemotherapy (NACT); safety; laparoscopic technique.

Prognostic value of pathological tumor regression grade in locally advanced gastric cancer: New perspectives from a single-center experience

BACKGROUND AND OBJECTIVE

Perioperative chemotherapy (PC) with radical surgery represents the gold standard of treatment for resectable advanced gastric cancer (GC). The prognostic value of pathological tumor regression grade (TRG) induced by neoadjuvant chemotherapy (NACT) is not clearly established. This study aimed to investigate the correlation between TRG and survival in GC.

METHODS

Patients affected by advanced GC undergoing PC and radical surgery were considered. TRG was assessed for each patient according to Becker's grading system. The correlation between TRG and survival was investigated.

RESULTS

One-hundred patients were selected; 25 showed a good response (GR) (TRG 1a/1b), while 75 had a poor response (PR) (TRG 2/3) to NACT. GR patients showed better disease-free survival (DFS) (52 vs. 19 months, p < .001) and disease-specific survival (DSS) (57 vs. 25 months, p < .0001) when compared to PR patients. On univariate analysis, TRG, lymph node ratio (LNR), tumor size, grading, and post-neoadjuvant therapy TNM stage were significantly correlated with survival. On multivariate analysis, TRG, LNR and tumor size were independent prognostic factors for DFS and DSS.

CONCLUSIONS

TRG, LNR, and tumor size are independent prognostic factors for DFS and DSS in patients with advanced GC undergoing NACT.

Providing Reliable Prognosis to Patients with Gastric Cancer in the Era of Neoadjuvant Therapies: Comparison of AJCC Staging Schemata

Purpose

Patients with gastric cancer who receive neoadjuvant therapy are staged before treatment (cStage) and after treatment (ypStage). We aimed to compare the prognostic reliability of cStage and ypStage, alone and in combination.

Materials and Methods

Data for all patients who received neoadjuvant therapy followed by surgery for gastric adenocarcinoma from 2004 to 2015 were extracted from the National Cancer Database. Kaplan-Meier (KM)curves were used to model overall survival based on cStage alone, ypStage alone, cStage stratified by ypStage, and ypStage stratified by cStage. P-values were generated to summarize the differences in KM curves. The discriminatory power of survival prediction was examined using Harrell's C-statistics.

Results

We included 8,977 patients in the analysis. As expected, increasing cStage and ypStage were associated with worse survival. The discriminatory prognostic power provided by cStage was poor (C-statistic 0.548), while that provided by ypStage was moderate (C-statistic 0.634). Within each cStage, the addition of ypStage information significantly altered the prognosis (P<0.0001 within cStages I–IV). However, for each ypStage, the addition of cStage information generally did not alter the prognosis (P=0.2874, 0.027, 0.061, 0.049, and 0.007 within ypStages 0–IV, respectively). The discriminatory prognostic power provided by the combination of cStage and ypStage was similar to that of ypStage alone (C-statistic 0.636 vs. 0.634).

Conclusions

The cStage is unreliable for prognosis, and ypStage is moderately reliable. Combining cStage and ypStage does not improve the discriminatory prognostic power provided by ypStage alone. A ypStage-based prognosis is minimally affected by the initial cStage.

Modified ypTNM Staging Classification for Gastric Cancer after Neoadjuvant Therapy: A Multi-Institutional Study

BACKGROUND

The benefits of neoadjuvant therapy for patients with locally advanced gastric cancer (GC) are increasingly recognized. The 8th edition of the American Joint Committee on Cancer (AJCC) Staging Manual first proposed ypTNM staging, but its accuracy is controversial. This study aims to develop a modified ypTNM staging.

PATIENTS AND METHODS

Clinicopathological data of 1,791 patients who underwent curative-intent gastrectomy after neoadjuvant therapy in the Surveillance, Epidemiology, and End Results database, as the development cohort, were retrospectively analyzed. Modified ypTNM staging was established based on overall survival (OS). We compared the prognostic performance of the AJCC 8th edition ypTNM staging and the modified staging for patients after neoadjuvant therapy.

RESULTS

In the development cohort, the 5-year OS for AJCC stages I, II, and III was 58.8%, 39.1%, and 21.6%, respectively, compared with 69.9%, 54.4%, 34.4%, 24.1%, and 13.6% for modified ypTNM stages IA, IB, II, IIIA, and IIIB. The modified staging had better discriminatory ability (C-index: 0.620 vs. 0.589, p < .001), predictive homogeneity (likelihood ratio chi-square: 140.71 vs. 218.66, p < .001), predictive accuracy (mean difference in Bayesian information criterion: 64.94; net reclassification index: 35.54%; integrated discrimination improvement index: 0.032; all p < .001), and model stability (time-dependent receiver operating characteristics curves) over AJCC. Decision curve analysis showed that the modified staging achieved a better net benefit than AJCC. In external validation (n = 266), the modified ypTNM staging had superior prognostic predictive power (all p < .05).

CONCLUSION

We have developed and validated a modified ypTNM staging through multicenter data that is superior to the AJCC 8th edition ypTNM staging, allowing more accurate assessment of the prognosis of patients with GC after neoadjuvant therapy.

IMPLICATIONS FOR PRACTICE

The 8th edition of the American Joint Committee on Cancer (AJCC) Staging Manual first proposed ypTNM staging, but its accuracy is controversial. Based on multi-institutional data, this study developed a modified ypTNM staging, which is superior to the AJCC 8th edition ypTNM staging, allowing more accurate assessment of the prognosis of patients with gastric cancer after neoadjuvant therapy.

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.

The role of MRI in the diagnosis and treatment of gastric cancer

Gastric cancer is the fifth most common malignancies and the third leading cause of cancer-related death worldwide, with more than 40% of new cases occurring in China. With the advancement of treatment methods, the application of adjuvant therapy and targeted drugs, the prognosis of patients with gastric cancer has been significantly improved. In recent years, more and more studies have reported that magnetic resonance imaging (MRI) showed great value in the clinical application among patients with gastric cancer, including preoperative staging, treatment response evaluation, predicting prognosis and histopathological features, treatment guidance, and molecular imaging. The remarkable research progress of MRI in gastric cancer will provide new evaluation and treatment approaches for clinical diagnosis and treatment. This article aims to review the current status of the application and research progress of MRI in patients with gastric cancer.

Evaluating the utility of computed tomography of the chest for gastric cancer staging

Background

International guidelines recommend routine computed tomography (CT) of the chest for gastric cancer staging. In Asian countries, where the incidence of pulmonary metastases is less than 1%, some guidelines recommend chest CT only for gastroesophageal junction cancers. If the incidence of pulmonary metastases is also low in Canada, routine chest CT may not be beneficial.

Methods

We performed a retrospective review of patients in northern Alberta with newly diagnosed gastric cancer from January 2010 to July 2016. The primary aim of the study was to determine the incidence of pulmonary metastases at the time of diagnosis in this population. A secondary aim was to identify potential predictors of pulmonary metastases. We reviewed CT reports for pulmonary metastases. Imaging data also included liver metastases, abdominal lymphadenopathy (> 1 cm), ascites and omental or peritoneal nodules. Other data recorded were age, sex, primary tumour location, histologic type and tumour grade.

Results

Four hundred and sixty-two patients (311 men, 151 women) were included in the analysis. Pulmonary metastases were identified in 25 patients (5.4%) overall and in 11 of 299 patients (3.7%) whose primary cancer was not in the cardia. On univariate analysis the presence of liver metastases (odds ratio [OR] 7.72, 95% confidence interval [CI] 3.24–18.37, p < 0.001) and abdominal lymphadenopathy (OR 3.30, 95% CI 1.29–8.48, p = 0.01) was associated with an increased risk of pulmonary metastases. Liver metastases retained statistical significance on multivariate analysis (OR 6.17, 95% CI 2.53–15.03, p < 0.001).

Conclusion

The incidence of pulmonary metastases at the time of gastric cancer diagnosis is higher in northern Alberta than previously reported in Asian studies. Abdominal lymphadenopathy and liver metastases confer an elevated risk of pulmonary metastases.

Negative lymph node count as an independent prognostic factor in stage III patients after curative gastrectomy: A retrospective cohort study based on a multicenter database

OBJECTIVE

To examine the prognostic value of negative lymph node (NLN) count in stage III gastric cancer (GC) patients after curative gastrectomy.

METHODS

The clinicopathological data of 2942 stage III patients who underwent curative gastrectomy between 2001 and 2011 were analyzed. Only patients with ≥16 examined lymph nodes (ELNs) were included. After cut-point survival analysis, the 2942 patients were divided into three subgroups with NLN counts of 0, 1-9, and ≥10. Survival differences among the subgroups were analyzed to assess the effects of NLN count on stage migration and overall survival (OS) in stage III GC patients. Spearman's correlation coefficient was used to assess the relationships between the ELN count and the positive lymph node (PLN) count, the ELN count and the NLN count, and the NLN count and the PLN count.

RESULTS

Survival analyses revealed that the NLN count was significantly associated with OS (P = 0.001) and was an independent predictor (P < 0.01) of prognosis in stage III GC patients. Subgroup analysis showed that the prognostic evaluation accuracy was highest when the NLN count was ≥10 for stage III patients. Stage migrations were mainly detected in the following pathological tumor-node (pTN) subgroups: pT2N3a with 1-9 NLNs and pT2N3b with ≥10 NLNs, and pT3N3a with 1-9 NLNs and pT3N3b with ≥10 NLNs. NLN count was positively correlated with the ELN and the PLN counts for pT2N3 and pT3N3 stage GC patients (r = 0.694 and r = 0.881 for pT2N3 patients; r = 0.685 and r = 0.902 for pT3N3 patients, respectively; P < 0.001). These findings indicate that the NLN count may be a useful prognostic predictor in stage III GC patients.

CONCLUSIONS

The NLN count may improve the prognostic prediction efficiency of the tumor-node-metastasis (TNM) classification for GC, especially for stage III patients, and should be recommended for clinical applications.

Inhibiting casein kinase 2 overcomes paclitaxel resistance in gastric cancer

PURPOSE

Casein kinase (CK) 2 activation has been implicated in the proliferation of various tumor types and resistance to chemotherapy. We investigated the mechanistic basis for the association between CK2 activation and paclitaxel resistance in a gastric cancer (GC).

EXPERIMENTAL DESIGN

CK2 expression was evaluated in 59 advanced GC patients treated with paclitaxel as the second-line therapy. The efficacy of a CK2 inhibitor, CX-4945, and paclitaxel was evaluated in GC cell lines and a xenograft model.

RESULTS

Patients with high CK2 expression (29/59, 39%) showed lower disease control rates (47.7% vs. 72.3%, p = 0.017) and shorter progression-free survival (2.8 vs. 4.8 months, p = 0.009) than patients with low CK2 expression. CK2 protein expression was associated with sensitivity to paclitaxel in 49 GC cell lines. Combination therapy with CX-4945 and paclitaxel exerted synergistic antiproliferative effects and inhibited the downregulation of phosphatidylinositol 3-kinase/AKT signaling in SNU-1 cells. In the SNU-1 xenograft model, the combination treatment was significantly superior to either single agent, suppressing tumor growth without notable toxicities.

CONCLUSIONS

These results demonstrated that CK2 activation was related to paclitaxel resistance and that CX-4945 in combination with paclitaxel could be used as a potential treatment for paclitaxel resistance in GC.

Development and validation of a staging system for gastric adenocarcinoma after neoadjuvant chemotherapy and gastrectomy with D2 lymphadenectomy

BACKGROUND

Neoadjuvant chemotherapy followed by gastrectomy with D2 lymphadenectomy is commonly used for patients with locally advanced gastric adenocarcinoma. The eighth AJCC ypTNM staging system was validated based on patients undergoing more limited lymphadenectomy (less than D2). The aim of this study was to develop a system for accurate staging of patients with locally advanced gastric adenocarcinoma who receive neoadjuvant chemotherapy followed by gastrectomy with D2 lymphadenectomy.

METHODS

A modified system of ypTNM was developed, based on overall survival (OS) of patients receiving neoadjuvant chemotherapy followed by gastrectomy with D2 lymphadenectomy at Memorial Sloan Kettering Cancer Center, and validated using data from an international cohort of patients who had similar treatment.

RESULTS

Of 325 patients in the derivation cohort, 33 (10·2 per cent) had ypT0 N0/+ tumours, which are not classifiable under the AJCC system. The 5-year OS rate for modified ypTNM stages I, II, IIIA and IIIB was 89, 71, 42·3 and 10 per cent respectively, compared with 82, 65·2 and 24·1 for AJCC stages I, II and III respectively. The concordance index (0·730 versus 0·709), estimated area under the curve (0·765 versus 0·740) and time-dependent receiver operating characteristic (ROC) curve throughout the observation period were all superior for modified ypTNM staging. For the validation cohort of 186 patients, the modified system was again better at separating patients into prognostic groups for OS.

CONCLUSION

The modified ypTNM staging system improves the accuracy of OS prediction for patients treated with neoadjuvant chemotherapy followed by gastrectomy with D2 lymphadenectomy.

Clinical significance of skip lymph-node metastasis in pN1 gastric-cancer patients after curative surgery

BACKGROUND

In addition to the stepwise manner of lymph-node metastasis from the primary tumour, the skip lymph-node metastasis (SLNM) was identified as a low-incidence metastasis of gastric cancer (GC). So far, both the mechanism and outcome of SLNM have not been elucidated completely. The purpose of this study was to analyse the clinical significance and the potential mechanism of SLNM in GC patients who had lymph-node metastasis.

METHODS

Clinicopathological data and follow-up information of 505 GC patients who had lymph-node metastasis were analysed to demonstrate the significance of SLNM in evaluating the prognostic outcome. According to the pathological results, all GC patients who had lymph-node metastasis were categorized into three groups: patients with the perigastric lymph-node metastasis, patients with the perigastric and extragastric lymph-node metastasis and patients with SLNM.Results: Among the 505 GC patients who had lymph-node metastasis, 24 (4.8%) had pathologically identified SLNM. The location of lymph-node metastasis was not significantly associated with 5-year survival rate and overall survival (OS) (P = 0.194). The stratified survival analysis results showed that the status of SLNM was significantly associated with the OS in patients with pN1 GC (P = 0.001). The median OS was significantly shorter in 19 pN1 GC patients with SLNM than in 100 patients with perigastric lymph-node metastasis (P < 0.001). The case-control matched logistic regression analysis results showed that tumour size (P = 0.002) was the only clinicopathological factor that may predict SLNM in pN1 GC patients undergoing curative surgery. Among the 19 pN1 GC patients with SLNM, 17 (89.5%) had metastatic lymph nodes along the common hepatic artery, around the celiac artery or in the hepatoduodenal ligament.

CONCLUSIONS

SLNM may be considered a potentially practicable indicator for prognosis among various subgroups of pN1 GC patients.

Ribophorin II potentiates P-glycoprotein- and ABCG2-mediated multidrug resistance via activating ERK pathway in gastric cancer

Multidrug resistance (MDR) is a critical reason of cancer chemotherapy failure. Ribophorin II (RPN2) has emerged as a vital regulator of MDR in multiple cancers including gastric cancer (GC). However, the roles and molecular mechanisms of RPN2 in MDR have not been well featured till now. The present study aimed to explore the roles and molecular mechanisms of RPN2 in MDR of drug-resistant GC cells. Results showed that the expressions of RPN2, multidrug resistance 1 (MDR1), and ATP binding cassette subfamily G member 2 (ABCG2) were upregulated in SGC7901/DDP and SGC7901/VCR cells. Knockdown of RPN2 alleviated MDR through downregulating MDR1 and ABCG2 expressions in SGC7901/DDP and SGC7901/VCR cells. RPN2 depletion inhibited the activation of MEK/ERK pathway. RPN2 overexpression enhanced MDR by upregulating P-glycoprotein (P-gp) and ABCG2 protein expressions in SGC7901/DDP or SGC7901/VCR cells, while this effect of RPN2 was abrogated by ERK knockdown or treatment with ERK inhibitor PD98059. Our findings suggested that RPN2 potentiated P-gp- and ABCG2-mediated MDR via activating MEK/ERK pathway in GC, hinting the critical values of RPN2 in ameliorating MDR and providing a promising target for GC therapy.

The long-term prognostic difference between gastrectomy with and without preoperative chemotherapy in patients with clinical stage IV gastric cancer

BACKGROUND/OBJECTIVE

The role of gastrectomy for stage IV gastric cancer (GC) has not yet been established. Thus, we aimed to compare the prognoses of patients with clinical stage IV GC who underwent gastrectomy with and without preoperative chemotherapy after precise recategorization of patients.

METHODS

We retrospectively reviewed a total of 92 clinical stage IV GC patients who underwent gastrectomy with or without preoperative chemotherapy between 2010 and 2016 at a single institution. Yoshida's classification was used to categorize the patients into the following categories: 1, technically resectable metastasis; 2, marginally resectable metastasis; 3, unresectable peritoneal dissemination; and 4, incurable peritoneal dissemination with distant organ metastasis. Two-year disease-specific survival (DSS) rates were compared between patients who underwent primary surgery and preoperative chemotherapy for each category.

RESULTS

The two-year DSS rates of primary surgery vs. preoperative chemotherapy in Categories 1, 2, 3, and 4 (n = 35, 39, 14, and 4, respectively) were 48.6% vs. 41.7% (p = 0.829), 52.6% vs. 40.0% (p = 0.855), 50.0% vs. 75.0% (p = 0.027), and 0% vs. 66.7% (p = 0.083), respectively. Patients in Categories 1 and 2 who underwent preoperative chemotherapy tended to have lower two-year DSS rates (p = 0.911), whereas patients in Categories 3 and 4 had significantly higher two-year DSS rates than those who underwent primary surgery (p = 0.014).

CONCLUSIONS

Primary surgery may be performed in patients without peritoneal dissemination when GC is technically resectable. However, if peritoneal dissemination is suspected, chemotherapy should be prioritized.

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

PURPOSE

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

Materials and Methods

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

RESULTS

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

CONCLUSION

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