Blood transfusion might not be recommended for gastric cancer patients with pretransfusion minimum hemoglobin values higher than 90 g/L: a real-world study covering 20 years of 13470 patients.

BACKGROUND: There was no consistent evidence whether perioperative blood transfusion (PBT) affects the long-term survival of gastric cancer (GC) patients after undergoing gastrectomy. This study aimed to investigate the effects of PBT on long-term survival of GC patients, as well as to determine the threshold of PBT and provide evidence for future surgical practice. METHODS: We performed this real-world study of GC patients undergoing gastrectomy in China National Cancer Center from January 1, 2000 to December 30, 2019. Overall survival (OS) curves were plotted using the Kaplan-Meier method and compared statistically using the log-rank test. Univariate and multivariate Cox proportional hazards models were used to determine the risk factors for OS. RESULTS: In total, 13470 GC patients undergoing gastrectomy from 2000 to 2019 was included, of whom 3465 (34.6%) GC patients received PBT. PBT ratios declined from 29.1% (114/392) in 2000 to 11.2% in 2019 (149/1178), with the highest blood transfusion ratio in 2005 at 43.7% (220/504). For patients transfused with red blood cells, the median value of hemoglobin (Hb) before transfusion in the PBT group decreased from 110 g/L in 2000 to 87 g/L in 2019. Compared with patients who not receiving perioperative blood transfusion (NPBT), PBT group are more likely to be older (≥65, 39.1% vs. 30.1%, P<0.001), open operation (89.7% vs. 78.1%, P<0.001), higher ASA score (>2, 25.3% vs. 14.9%, P<0.001) and in the later pTNM stage (pTNM stage III, 68.5% vs. 51.5%, P<0.001). Results of multivariable Cox regression analysis showed that PBT was an independent prognostic factor for worse OS in GC patients undergoing gastrectomy (HR=1.106, 95% CI, 1.01-1.211, P=0.03). After stratified according to tumor stage, we found that PBT group had a worse prognosis only in pTNM stage III (HR=1.197, 95% CI, 1.119-1.281, P<0.001). OS was obviously poor in the PBT group when Hb levels were higher than 90 g/L (90 g/L120 g/L:HR= 1.207, 95% CI, 1.098-1.327, P<0.001), while there was no difference between the two groups when Hb levels were lower than or equal to 90 g/L (Hb≤90 g/L: HR=1.162, 95% CI, 0.985-1.370, P=0.075). CONCLUSION: In conclusion, PBT was an independent prognostic factor for worse OS. Blood transfusion might not be recommended for gastric cancer patients with perioperative minimum Hb values higher than 90 g/L.

Concurrent clinical and pathological response predicts favorable prognosis of patients with gastric cancer after neoadjuvant therapy: a real-world study.

BACKGROUND: Response of locally advanced gastric cancer (LAGC) to neoadjuvant therapy (NAT) may be associated with prognosis, but which of the clinical or pathological evaluation can accurately predict a favorable prognosis is still controversial. This study aims to compare the effect of clinical and pathological response on the prognosis of patients with gastric cancer. METHODS: This study retrospectively analyzed LAGC patients who underwent NAT followed by surgery in the China National Cancer Center from January 2004 to January 2021. Clinical and pathological responses after NAT were evaluated using RECIST 1.1 and Mandard tumor regression grade system (TRG) respectively. Complete response (CR) and partial response (PR) assessed by computed tomography were regarded as clinical response. For histopathology regression assessment, response was defined as Mandard 1, 2, 3 and non-response as Mandard 4, 5. Furthermore, we combined clinical and pathological evaluation results into a variable termed "comprehensive assessment" and divided it into four groups based on the presence or absence of response (concurrent response, only clinical response, only pathological response, both non-response). The association between the prognosis and clinicopathological factors was assessed in univariate and multivariate Cox regression analysis. RESULTS: In total, 238 of 1073 patients were included in the study after screening. The postoperative pathological response rate and clinical response rate were 50.84% (121/238) and 39.92% (95/238), respectively. 154 patients got consistent results in clinical and pathological evaluation (66 were concurrent response and 88 were both non-response), while the other 84 patients did not. The kappa value was 0.297(p < 0.001), which showed poor consistency. Multivariate Cox regression analysis revealed that comprehensive assessment (P = 0.03), clinical N stage(P < 0.001), vascular or lymphatic invasion (VOLI) (HR 2.745, P < 0.001), and pre-CA724(HR 1.577, P = 0.047) were independent factors for overall survival in patients with gastric cancer. Among four groups in the comprehensive assessment, concurrent response had significantly better survival (median OS: 103.5 months) than the other groups (P = 0.008). CONCLUSION: Concurrent clinical and pathological response might predict a favorable prognosis of patients with gastric cancer after neoadjuvant therapy, further validation is needed in prospective clinical trials with larger samples.

The minimum number of examined lymph nodes was 24 for optimal survival of pathological T2-4 gastric cancer: a multi-center, hospital-based study covering 20 years of data.

INTRODUCTION: The current National Comprehensive Cancer Network (NCCN) guidelines recommend that at least 16 lymph nodes should be examined for gastric cancer patients to reduce staging migration. However, there is still debate regarding the optimal management of examined lymph nodes (ELNs) for gastric cancer patients. In this study, we aimed to develop and test the minimum number of ELNs that should be retrieved during gastrectomy for optimal survival in patients with gastric cancer. METHODS: We used the restricted cubic spline (RCS) to identify the optimal threshold of ELNs that should be retrieved during gastrectomy based on the China National Cancer Center Gastric Cancer (NCCGC) database. Northwest cohort, which sourced from the highest gastric cancer incidence areas in China, was used to verify the optimal cutoff value. Survival analysis was performed via Kaplan-Meier estimates and Cox proportional hazards models. RESULTS: In this study, 12,670 gastrectomy patients were included in the NCCGC cohort and 4941 patients in the Northwest cohort. During 1999-2019, the average number of ELNs increased from 17.88 to 34.45 nodes in the NCCGC cohort, while the number of positive lymph nodes remained stable (5-6 nodes). The RCS model showed a U-curved association between ELNs and the risk of all-cause mortality, and the optimal threshold of ELNs was 24 [Hazard ratio (HR) = 1.00]. The ELN ≥ 24 group had a better overall survival (OS) than the ELN < 24 group clearly (P = 0.003), however, with respect to the threshold of 16 ELNs, there was no significantly difference between the two groups (P = 0.101). In the multivariate analysis, ELN ≥ 24 group was associated with improved survival outcomes in total gastrectomy patients [HR = 0.787, 95% confidence interval (CI): 0.711-0.870, P < 0.001], as well as the subgroup analysis of T2 patients (HR = 0.621, 95%CI: 0.399-0.966, P = 0.035), T3 patients (HR = 0.787, 95%CI: 0.659-0.940, P = 0.008) and T4 patients (HR = 0.775, 95%CI: 0.675-0.888, P < 0.001). CONCLUSION: In conclusion, the minimum number of ELNs for optimal survival of gastric cancer with pathological T2-4 was 24.

Impact of HER2 on prognosis and benefit from adjuvant chemotherapy in stage II/III gastric cancer patients: a multicenter observational study.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) is a well-developed therapeutic target in breast and gastric cancer (GC). However, the impact of HER2 on survival and benefit from fluorouracil-based adjuvant chemotherapy remains unclear in patients with GC. MATERIALS AND METHODS: This multicenter cohort study involved 5622 consecutive stage II/III GC patients. HER2 expression was assessed prospectively via immunohistochemistry (IHC). The staining intensity was graded on a scale of 0 to 3+. An IHC score of 2+or 3+was defined as high expression, and a score of 3+was defined as overexpression. RESULTS: HER2 overexpression was independently associated with a lower 5-year overall survival (OS) in stage II [hazard ratio (HR), 2.10; 95% CI: 1.41-3.11], but not in stage III GC (HR, 1.00; 95% CI, 0.82-1.20). Further analysis revealed that stage II patients with high HER2 expression showed a poorer response to chemotherapy than stage II patients with low HER2 expression ( Pinteraction =0.024). The HRs for 5-year OS were 0.51 (95% CI, 0.38-0.70) for stage II patients with low HER2 expression, 0.58 (95% CI, 0.51-0.66) for stage III patients with low HER2 expression, 1.13 (95% CI, 0.61-2.09) for stage II patients with high HER2 expression, and 0.47 (95% CI, 0.36-0.61) for stage III patients with high HER2 expression. CONCLUSIONS: Fluorouracil-based adjuvant chemotherapy is insufficient for stage II GC patients with high HER2 expression, indicating that prospective trials are required to validate alternative HER2-targeted adjuvant therapies in the individuals above.

Perioperative Chemotherapy Could Not Improve the Prognosis of Gastric Cancer Patients With Mismatch Repair Deficiency: A Multicenter, Real-World Study.

INTRODUCTION: To date, the role of deficient mismatch repair (dMMR) remains to be proven in gastric cancer, and it is difficult to judge its value in clinical application. Our study aimed to investigate how MMR status affected the prognosis in patients with gastrectomy, as well as the efficacy of neoadjuvant chemotherapy and adjuvant chemotherapy in patients with dMMR with gastric cancer. MATERIALS AND METHODS: Patients with gastric cancer with certain pathologic diagnosis of dMMR or proficient MMR (pMMR) using immunohistochemistry from 4 high-volume hospitals in China were included. Propensity score matching was used to match patients with dMMR or pMMR in 1:2 ratios. Overall survival (OS) and progression-free survival (PFS) curves were plotted using the Kaplan-Meier method and compared statistically using the log-rank test. Univariate and multivariate Cox proportional hazards models based on hazard ratios (HRs) and 95% confidence intervals (CIs) were used to determine the risk factors for survival. RESULTS: In total, data from 6176 patients with gastric cancer were ultimately analyzed, and loss of expression of one or more MMR proteins was observed in 293 patients (293/6176, 4.74%). Compared to patients with pMMR, patients with dMMR are more likely to be older (≥66, 45.70% vs. 27.94%, P < .001), distal location (83.51% vs. 64.19%, P < .001), intestinal type (42.21% vs. 34.46%, P < .001), and in the earlier pTNM stage (pTNM I, 32.79% vs. 29.09%, P = .009). Patients with gastric cancer with dMMR showed better OS than those with pMMR before PSM (P = .002); however, this survival advantage was not observed for patients with dMMR after PSM (P = .467). As for perioperative chemotherapy, results of multivariable Cox regression analysis showed that perioperative chemotherapy was not an independent prognostic factor for PFS and OS in patients with dMMR with gastric cancer (HR = 0.558, 95% CI, 0.270-1.152, P = .186 and HR = 0.912, 95% CI, 0.464-1.793, P = .822, respectively). CONCLUSION: In conclusion, perioperative chemotherapy could not prolong the OS and PFS of patients with dMMR with gastric cancer.

Survival benefit of younger gastric cancer patients in China and the United States: A comparative study.

BACKGROUND: The impact of racial and regional disparity on younger patients with gastric cancer (GC) remains unclear. AIM: To investigate the clinicopathological characteristics, prognostic nomogram, and biological analysis of younger GC patients in China and the United States. METHODS: From 2000 to 2018, GC patients aged less than 40 years were enrolled from the China National Cancer Center and the Surveillance Epidemiology and End Results database. Biological analysis was performed based on the Gene Expression Omnibus database. Survival analysis was conducted via Kaplan-Meier estimates and Cox proportional hazards models. RESULTS: A total of 6098 younger GC patients were selected from 2000 to 2018, of which 1159 were enrolled in the China National Cancer Center, and 4939 were collected from the Surveillance Epidemiology and End Results database. Compared with the United States group, younger patients in China revealed better survival outcomes (P < 0.01). For race/ethnicity, younger Chinese cases also enjoyed a better prognosis than that in White and Black datasets (P < 0.01). After stratification by pathological Tumor-Node-Metastasis (pTNM) stage, a survival advantage was observed in China with pathological stage I, III, and IV (all P < 0.01), whereas younger GC patients with stage II showed no difference (P = 0.16). In multivariate analysis, predictors in China involved period of diagnosis, linitis plastica, and pTNM stage, while race, diagnostic period, sex, location, differentiation, linitis plastica, signet ring cell, pTNM stage, surgery, and chemotherapy were confirmed in the United States group. Prognostic nomograms for younger patients were established, with the area under the curve of 0.786 in the China group and of 0.842 in the United States group. Moreover, three gene expression profiles (GSE27342, GSE51105, and GSE38749) were enrolled in further biological analysis, and distinctive molecular characteristics were identified in younger GC patients among different regions. CONCLUSION: Except for younger cases with pTNM stage II, a survival advantage was observed in the China group with pathological stage I, III, and IV compared to the United States group, which might be partly due to differences in surgical approaches and the improvement of the cancer screening in China. The nomogram model provided an insightful and applicable tool to evaluate the prognosis of younger patients in China and the United States. Furthermore, biological analysis of younger patients was performed among different regions, which might partly explain the histopathological behavior and survival disparity in the subpopulations.

Using nomogram, decision tree, and deep learning models to predict lymph node metastasis in patients with early gastric cancer: a multi-cohort study.

The accurate assessment of lymph node metastasis (LNM) in patients with early gastric cancer is critical to the selection of the most appropriate surgical treatment. This study aims to develop an optimal LNM prediction model using different methods, including nomogram, Decision Tree, Naive Bayes, and deep learning methods. In this study, we included two independent datasets: the gastrectomy set (n=3158) and the endoscopic submucosal dissection (ESD) set (n=323). The nomogram, Decision Tree, Naive Bayes, and fully convolutional neural networks (FCNN) models were established based on logistic regression analysis of the development set. The predictive power of the LNM prediction models was revealed by time-dependent receiver operating characteristic (ROC) curves and calibration plots. We then used the ESD set as an external cohort to evaluate the models' performance. In the gastrectomy set, multivariate analysis showed that gender (P=0.008), year when diagnosed (2006-2010 year, P=0.265; 2011-2015 year, P=0.001; and 2016-2020 year, P<0.001, respectively), tumor size (2-4 cm, P=0.001; and ≥4 cm, P<0.001, respectively), tumor grade (poorly-moderately, P=0.016; moderately, P<0.001; well-moderately, P<0.001; and well, P<0.001, respectively), vascular invasion (P<0.001), and pT stage (P<0.001) were independent risk factors for LNM in early gastric cancer. The area under the curve (AUC) for the validation set using the nomogram, Decision Tree, Naive Bayes, and FCNN models were 0.78, 0.76, 0.77, and 0.79, respectively. In conclusion, our multi-cohort study systematically investigated different LNM prediction methods for patients with early gastric cancer. These models were validated and shown to be reliable with AUC>0.76 for all. Specifically, the FCNN model showed the most accurate prediction of LNM risks in early gastric cancer patients with AUC=0.79. Based on the FCNN model, patients with LNM rates of >4.77% are strong candidates for gastrectomy rather than ESD surgery.

At least 16 lymph nodes are recommended to examine during pancreaticoduodenectomy in ampullary adenocarcinoma.

The minimum number of lymph nodes to be examined during pancreaticoduodenectomy (PD) for patients with ampullary adenocarcinoma (AC) is still debatable due to limited clinical data. Therefore, here we explored the relationship between the number of examined lymph node (ELN) and the current N staging (American Joint Committee on Cancer staging system, AJCC, 8 edition) after PD for AC as well as determined the minimum number of examined lymph nodes (MNELN) to ensure the accurate detection of nodal involvement. Patients underwent PD for AC in the National Cancer Center cohort of China (NCC cohort of China) from 1998 to 2020 and in the Surveillance, Epidemiology, and End Results database (SEER database) from 2010 to 2018 were retrospectively reviewed, and a total of 452 eligible patients were included in this study. The MNELN was evaluated by binomial probability law and best survival separation methods. Furthermore, the cut-off value of MNELN was validated in the NCC cohort of China using Least Absolute Shrinkage and Selection Operator (LASSO) regression. Our analysis indicated that the median number of ELN was 14, and the number of ELN was positively correlated with N stage. The MNELN was 16, whereas the best survival separation of ELN was 38 in node-positive patients and 3 in node-negative patients. In the validation cohort, the number of 16 ELNs was identified as a predictive variable for lymph node metastasis with nonzero coefficients in the LASSO-logistic regression model. Together, we concluded that a greater number of ELN was associated with more accurate nodal status assessment in PD for AC patients. A minimum of 16 lymph nodes were required to during PD in AC patients.

Reconstruction of the gastric cancer microenvironment after neoadjuvant chemotherapy by longitudinal single-cell sequencing.

BACKGROUND: Little is known on the tumor microenvironment (TME) response after neoadjuvant chemotherapy (NACT) in gastric cancer on the molecular level. METHODS: Here, we profiled 33,589 cell transcriptomes in 14 samples from 11 gastric cancer patients (4 pre-treatment samples, 4 post-treatment samples and 3 pre-post pairs) using single-cell RNA sequencing (scRNA-seq) to generate the cell atlas. The ligand-receptor-based intercellular communication networks of the single cells were also characterized before and after NACT. RESULTS: Compered to pre-treatment samples, CD4+ T cells (P = 0.018) and CD8+ T cells (P = 0.010) of post-treatment samples were significantly decreased, while endothelial cells and fibroblasts were increased (P = 0.034 and P = 0.005, respectively). No significant difference observed with respect to CD4+ Tregs cells, cycling T cells, B cells, plasma cells, macrophages, monocytes, dendritic cells, and mast cells (P > 0.05). In the unsupervised nonnegative matrix factorization (NMF) analysis, we revealed that there were three transcriptional programs (NMF1, NMF2 and NMF3) shared among these samples. Compared to pre-treatment samples, signature score of NMF1 was significantly downregulated after treatment (P = 0.009), while the NMF2 signature was significantly upregulated after treatment (P = 0.013). The downregulated NMF1 and upregulated NMF2 signatures were both associated with improved overall survival outcomes based on The Cancer Genome Atlas (TCGA) database. Additionally, proangiogenic pathways were activated in tumor and endothelial cells after treatment, indicating that NACT triggers vascular remodeling by cancer cells together with stromal cells. CONCLUSIONS: In conclusion, our study provided transcriptional profiles of TME between pre-treatment and post-treatment for in-depth understanding on the mechanisms of NACT in gastric cancer and empowering the development of potential optimized therapy procedures and novel drugs.

Sex Disparity in Patients with Gastric Cancer: A Systematic Review and Meta-Analysis.

Objective: This systematic review and meta-analysis aimed to ascertain whether sex-based differences influence clinicopathological characteristics and survival outcomes of gastric cancer patients. Background: Gastric cancer in females has received less attention than in males. Clinicopathological features and survival outcomes of females with gastric cancer have been reported in several studies with controversial results. Methods: We systematically reviewed clinical studies from PubMed, Cochrane Library, Embase, and Web of Science published up to June 2022. The effect sizes of the included studies were estimated using odds ratios (ORs). Heterogeneity was investigated using the χ2 and I 2 tests, while sensitivity analyses were performed to identify the source of substantial heterogeneity. All data used in this study were obtained from previously published studies obviating the need for ethical approval and patient consent. Results: Seventy-six studies with 775,003 gastric cancer patients were included in the meta-analysis. Gastric cancer patients were less likely to be females (P < 0.00001). Female patients were younger in age (P < 0.00001) and showed a higher percentage of distal (P < 0.00001), non-cardia (P < 0.00001), undifferentiated (P < 0.00001), diffuse (P < 0.00001), and signet-ring cell carcinoma (P < 0.00001). Female patients showed better prognosis in both 3-year (P = 0.0003) and 5-year overall survival (OS) (P < 0.00001), especially White patients. However, females were associated with lower 5-year OS relative to males in the younger patients (P = 0.0001). Conclusions: In conclusion, gender differences were observed in clinicopathological characteristics and survival outcomes of gastric cancer. Different management of therapy will become necessary for different genders.

Short-term safety and Long-term efficacy of multivisceral resection in pT4b gastric cancer patients without distant metastasis: a 20-year experience in China National Cancer Center.

Background: Multivisceral resection is occasionally necessary for pT4b gastric cancer patients to achieve negative margin. The purpose of this study is to assess the short-term safety and long-term efficacy of this approach. Methods: A single-center, retrospective analysis was conducted for pT4b gastric cancer patients after curative-intent multivisceral resection from the China National Cancer Center Gastric Cancer Database (NCCGCDB) from 1998 to 2018. The postoperative complications, recurrence patterns, long-term survival, and prognostic factors were analyzed. Results: A total of 210 patients were included in the study. The most common combined resection organs were multiple organs (30.5%), pancreas (20.5%), colon (16.7%), and liver (9.0%). Seventeen patients (8.1%) developed postoperative complications and hospital death was observed in one patient (0.5%). The most common postoperative complications were anastomotic leak (4.3%) and intra-abdominal infection (5.7%). The 3-year and 5-year disease-free survival (DFS) rates for the patients investigated were 38.0% and 33.8%, respectively, and the 3-year and 5-year overall survival (OS) rates were 48.2% and 39.1%, respectively. Multivariate Cox regression analysis proved that negative nerve invasion was independent risk factors for DFS (HR: 2.202, 95%CI: 1.144-4.236, P=0.018) and OS (HR: 2.219, 95%CI: 1.164-4.231, P=0.015). Conclusions: Multivisceral resection in pT4b gastric cancer patients without distant metastasis was effective and had an acceptable safety profile.

Long-term survival and pattern of recurrence in ampullary adenocarcinoma patients after curative Whipple's resection: a retrospective cohort study in the National Cancer Center in China.

Due to the low incidence of ampullary adenocarcinoma (AA), the recurrence patterns, risk factors for recurrence and post-recurrence treatment are still debated. The purpose of this study is to clarify such clinical issues based on the retrospective data at the National Cancer Center in China. Finally, one hundred and eighty-two AA patients after curative Whipple's resection from 1998 to 2019 were retrospectively reviewed. Among them, 27 patients had locoregional recurrence and 61 patients had systemic recurrence. However, no significant difference of clinicopathological features and survival were found between locoregional recurrence and distant metastasis. In the recurrence group, the 1-year, 2-year, and 3-year recurrence-free survival and overall survival were 59.1%, 29.5%, 10.2%, 88.6%, 61.6%, and 37.6%, respectively. AA patients with recurrence have a worse prognosis than those without recurrence, regardless of stage. In addition, we found that advanced T stage and lymphovascular invasion were two independent risk factors for RFS in AA patients after curative Whipple's resection. In conclusion, AA patients with recurrence have a poor prognosis. Advanced T stage and lymphovascular invasion were two independent risk factors for recurrence-free survival in AA patients after curative Whipple's resection. Nevertheless, further studies with larger sample sizes are needed to fully validate.

Resection of the Primary Tumor Improves the Survival of Patients With Stage IV Gastric Neuroendocrine Carcinoma.

Background: The prognostic prolongation effect of surgical resection in the management of gastric neuroendocrine carcinoma (GNEC) with distant metastases was still uncertain. The purpose of this study was to investigate the association of primary tumor resection (PTR) with outcomes in patients with stage IV GNEC. Methods: This retrospective study analyzed patients with distant metastatic GNEC diagnosed between 2000 and 2018 and identified using the Surveillance, Epidemiology, and End Results (SEER) database. Patients were divided into PTR and non-PTR groups. The stabilized inverse probability of treatment weighting (IPTW) method was used to reduce the selection bias. Overall survival (OS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier method and log-rank test. Cox-regression analyses (uni- and multivariate) were performed to evaluate factors potentially influencing survival. Results: A total of 126 patients with a median follow-up of 79 months were identified. Forty-four patients underwent PTR and 82 patients did not undergo surgery. After the IPTW approach, PTR improved the OS in patients with stage IV GNEC (median OS 12 vs. 6 months, P = 0.010). The 1- and 3-year OS for patients with or without PTR were 43.8% and 34.5%, and 27.9% and 6.5%, respectively. The median CSS was 12 months for patients undergoing PTR and 6 months for those who did not. The 1 and 3-year CSS for patients with or without PTR were 45.1% and 37.0%, and 27.9% and 6.5%, respectively. In IPTW-adjusted Cox proportional hazards regression analysis, PTR was recognized as an independent factor for improved survival after the occurrence of distant metastatic disease [OS: hazard ratio (HR) = 0.305; 95% confidence interval (CI): 0.196, 0.475; and CSS: HR = 0.278; 95% CI: 0.171, 0.452]. Conclusion: PTR for stage IV GNEC contributes to a better prognosis compared with non-surgery. This study supported the resection of the primary tumor in patients with distant metastatic GNEC.

The molecular mechanisms of CTHRC1 in gastric cancer by integrating TCGA, GEO and GSA datasets.

Collagen triple helix repeat containing-1 (CTHRC1), highly expressed in multiple human solid tumors, has been identified as a tumor associated protein. However, its specific role and mechanism with immune infiltrates in gastric cancer are still unclear. In this study, we systematically explored and validated the expression and prognostic value of CTHRC1 in gastric cancer by integrating the Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and Genome Sequence Archive (GSA) datasets. Compared to adjacent normal tissues, we observed that CTHRC1 was highly overexpressed in tumor sample of multiple cancers. It was revealed that CTHRC1 overexpression was positively correlated with the T stage in gastric cancer but not lymph nodes metastasis from TCGA dataset. In addition, CTHRC1 expression may induce tumor associated macrophage infiltration though GRN/TNFRSF1A and AnxA1/FPR1 pathways and also tumor angiogenesis in gastric cancer. In this context, our results indicate that CTHRC1 plays a pivotal role in regulating the angiogenesis and macrophage infiltration in tumor microenvironment, and also can predict poor prognosis in gastric cancer, suggesting that CTHRC1 might be a promising novel immunotherapy and angiogenesis target for gastric cancer.

Better Prognosis of Gastric Neuroendocrine Carcinoma Than Gastric Adenocarcinoma among Whites in the United States: A Propensity Score Matching Analysis Based on SEER.

It was generally believed that the prognosis of gastric neuroendocrine carcinoma (GNEC) was worse than gastric adenocarcinoma (GAC). However, almost all previous studies compared the prognosis of GNEC and GAC based on East Asians. In this study, we evaluated the clinicopathological features and prognosis of GNEC and GAC in Whites. Patients with GNEC and GAC were identified from 2000 to 2018 in the Surveillance, Epidemiology, and End Results (SEER) database. We used propensity score matching (PSM) analysis to match the age, sex, TNM stage, and treatments received between GNEC and GAC, then compared the overall survival (OS) and cancer-specific survival (CSS) in the two types. A total of 392 cases of GNEC and 12,835 cases of GAC in Whites were recognized. After PSM, the 5-year OS rates of GNEC and GAC were 50.3% and 43.0%, respectively (p = 0.010). The 5-year CSS rates of GNEC and GAC were 57.4% and 50.1%, respectively (p = 0.012). Besides, multivariable cox regression analyses showed that GNEC was an independent predictor of improved OS (HR 0.719; 95% CI 0.607-0.853) and CSS (HR 0.691; 95% CI 0.571-0.835) in the matched data. The prognosis of GNEC was better than GAC in Whites, showing significant ethnic differences. Appropriate treatments and follow-up strategies for GNEC in Whites are probably different from East Asians. The potential genetic and molecular mechanisms need to be further explored.

Single-cell landscape reveals active cell subtypes and their interaction in the tumor microenvironment of gastric cancer.

Background: Gastric cancer remains the third most common cause of cancer-related death worldwide. The development of novel therapeutic strategies for gastric cancer requires a deep understanding of the tumor cells and microenvironment of gastric cancer. Methods: We performed the single-cell RNA sequencing (scRNA-seq) on nine untreated non-metastatic gastric cancer patients. The transcriptomic atlas and ligand-receptor-based intercellular communication networks of the single cells were characterized. Results: Here, we profiled the transcriptomes of 47,304 cells from nine patients with gastric cancer. Tregs cells were significantly enriched in the gastric tumor tissues with increased expression of immune suppression related genes, which suggest a more immunosuppressive microenvironment. We also observed the absence of separate exhausted CD8+ T cell cluster, and the low expression level of exhaustion markers PDCD1, CTLA4, HAVCR2, LAG-3, and TIGIT in those specific cells. These may serve as molecular-level evidence for the limited benefit of immunotherapy among gastric cancer patients. In addition, we found ACKR1 specifically expressed in tumor endothelial cells, associated with poor prognosis in the cohort data and potentially provided a novel target of gastric cancer treatment. Furthermore, the tight interaction between endothelial cells and fibroblast implied the important roles of fibroblast in tumor angiogenesis and the maintenance of tumor vasculature. Conclusions: In conclusion, this single-cell atlas provide understanding the cellular heterogeneity from molecular level in gastric cancer and will serve as a valuable resource for developing innovative early and companion diagnostics, as well as discovering novel targeted therapies for gastric cancer.

Clinicopathological characteristics, survival outcomes, and genetic alterations of younger patients with gastric cancer: Results from the China National Cancer Center and cBioPortal datasets.

BACKGROUND: The survival outcomes of younger patients with gastric cancer (GC) have remained controversial. This study explores the clinicopathological characteristics, survival outcomes, and genetic alterations of younger and older patients with GC. METHODS: Patients with GC were identified from the China National Cancer Center Gastric Cancer Database (NCCGCDB) during 1998-2018. Survival analysis was conducted using Kaplan-Meier estimates and Cox proportional hazards models. Sequencing datasets were enrolled from The Cancer Genome Atlas (TCGA) and Memorial Sloan-Kettering Cancer Center (MSKCC) databases. RESULTS: A total of 1146 younger (<40 years of age) and 16,988 older (≥40 years of age) cases were included in the study. Younger patients had more poorly differentiated lesions than older patients (53.7% vs. 33.8%, respectively; p < 0.0001), and were more often pTNM stage IV (19.5% vs. 11.8%, respectively; p < 0.001). The 5-year overall survival (OS) of patients from the NCCGCDB increased from 1998 to 2018. Younger patients with pTNM stage III had a lower survival rate than older patients (p = 0.014), while no differences by age were observed at other stages. The mutation frequency of the LRP1B, GNAS, APC, and KMT2D genes was higher for older than younger patients (p < 0.05 for all genes). While not significantly different, younger patients from the TCGA and MSKCC databases were more likely to have CDH1, RHOA, and CTNNB1 gene mutations. CONCLUSIONS: A stable proportion and improved survival of younger patients were reported using NCCGCDB data. Younger patients with pTNM stage III had lower rates of survival than older patients. Distinct molecular characteristics were identified in younger GC patients which may partly explain the histopathology and prognosis specific to this subpopulation.

Effects of perioperative blood transfusion in gastric cancer patients undergoing gastrectomy: A systematic review and meta-analysis.

Background: The short-term and long-term effects of perioperative blood transfusion (PBT) on patients with gastric cancer are still intriguing. This systematic review and meta-analysis aimed to investigate the effects of blood transfusion on clinical outcomes in patients with gastric cancer undergoing gastrectomy. Methods: We searched PubMed, Web of Science, Embase, and The Cochrane Library on December 31th 2021. The main outcomes were overall survival (OS), disease-free survival (DFS), disease-specific survival (DFS), and postoperative complications. A fixed or random-effects model was used to calculate the hazard ratio (HR) with 95% confidence intervals (CIs). Results: Fifty-one studies with a total of 41,864 patients were included for this review and meta-analysis. Compared with patients who did not receive blood transfusions (NPBT), PBT was associated with worse 5-year OS (HR = 2.39 [95%CI: 2.00, 2.84]; p < 0.001; Multivariate HR = 1.43 [95%CI: 1.24, 1.63]; p < 0. 001), worse 5-year DFS (HR = 2.26 [95%CI: 1.68, 3.05]; p < 0.001; Multivariate HR = 1.45 [95%CI: 1.16, 1.82]; p < 0. 001), and worse 5-year DSS (HR = 2. 23 [95%CI: 1.35, 3.70]; p < 0.001; Multivariate HR = 1.24 [95%CI: 0.96, 1.60]; p < 0.001). Moreover, The PBT group showed a higher incidence of postoperative complications [OR = 2.30 (95%CI:1.78, 2. 97); p < 0.001] than that in the NPBT group, especially grade III-V complications, according to the Clavien-Dindo classification. [OR = 2.50 (95%CI:1.71, 3.63); p < 0.001]. Conclusion: In patients who underwent gastrectomy, PBT was associated with negative survival effects (OS, DFS, DSS) and a higher incidence of perioperative complications. However, more research was expected to further explore the impact of PBT. Meanwhile, strict blood transfusion management should be implemented to minimize the use of PBT.

Regional and racial disparity in proximal gastric cancer survival outcomes 1996-2016: Results from SEER and China National Cancer Center database.

BACKGROUND: Given the growing incidence and aggressive biological behavior of proximal gastric cancer (PGC) as reported, it is important to understand which regional or racial populations are at poor prognosis so that interventions can be treated appropriately. We sought to explore regional treatment differences as well as racial genes influence survival outcomes in China and the US patients with PGC. METHODS: PGC patients defined as tumors with the epicenter located in cardia (C16.0) or fundus (C16.1) from 1996 to 2016 were identified from the Surveillance Epidemiology and End Results (SEER) in the United States as well as data from a high-volume National Cancer Center Database in China. Overall survival (OS) curves were plotted for different regional or racial groups, respectively, using the Kaplan-Meier method and compared statistically using the log-rank test. Differentially expressed genes (DEGs) analysis was performed using TCGA database. RESULTS: Finally, the cohort consistent of 40973 PGC patients who enrolled in SEER database (n = 36305) or China National Cancer Center (n = 4668), and divided into 4 racial groups: Chinese (n = 5179), Black (n = 2429), White (n = 31185), and Others (n = 2096). After controlling for confounding variables, racial factors were independently associated with poor survival included Black ethnicity (HR = 1.376, 95% CI: 1.066-1.7760, p = 0.014) and White ethnicity (HR = 1.262, 95% CI: 1.005-1.583, p = 0.045) when compared to Chinese ethnicity in total PGC patients. Even in the same region for only US group, Chinese PGC patients also showed better prognosis. CONCLUSIONS: In conclusion, we demonstrated the different survival outcomes of PGC patients in different regions or races from two high-volume database SEER and China National Cancer Center database. These survival differences are likely influenced by a number of factors (e.g., access to screening, quality of gastrectomy, neo/adjuvant therapy, and biological genes itself). More importantly, a better understanding of these disparities could lead to interventions that may help to abolish these disparities.

Exceeding 30 ELNs is strongly recommended for pT3-4N0 patients with gastric cancer: A multicenter study of survival, recurrence, and prediction model.

The argument concerning the exact minimum number of examined lymph nodes (ELNs) has continued for a long time among various regions, and no consensus has been reached for stratified pathological T stages for data to date. Data from 4607 pN0 patients with gastric cancer were analyzed. Kaplan-Meier analysis showed the similar overall survival (OS) outcomes among the 3 groups (ELNs ≤ 15, 16 ≤ ELNs ≤ 29 and ELNs ≥ 30, P = .171). However, the ELNs ≥ 30 group had a better disease-free survival (DFS) outcome compared with the others (all P < .05). An increased ELN group (ELNs ≥ 30) showed an improved OS only for pT3 patients (hazard ratio [HR] = 0.397, 95% confidence interval (CI): 0.182-0.866, P = .020), while an improved DFS for pT3 patients (HR = 0.362, 95%CI: 0.152-0.860, P = .021) and pT4 patients (HR = 0.484, 95%CI: 0.277-0.844, P = .011) in the multivariate analysis. A well discriminated and calibrated nomogram was constructed to predict the probability of the OS and DFS, with the C-index for OS and DFS prediction of 0.782 (95%CI: 0.735 to 0.829) and 0.738 (95%CI: 0.685 to 0.791), respectively. This study provides new and useful insights into the impact of ELN count on reducing stage migration and postoperative recurrence of pN0 patients with gastric cancer in 2000-2017. In conclusion, a larger number of ELNs is suggested for surgeons to prolong the prognosis of pN0 gastric cancer, especially for pT3 patients.