The safety and efficacy of neoadjuvant immunochemotherapy following laparoscopic gastrectomy for gastric cancer: a multicenter Real-world clinical study.

BACKGROUND: The safety and efficacy of neoadjuvant immunochemotherapy (nICT) for locally advanced gastric cancer (LAGC) remain controversial. METHODS: Patients with LAGC who received either nICT or neoadjuvant chemotherapy (nCT) at 3 tertiary referral teaching hospitals in China between January 2016 and October 2022 were analysed. After propensity-score matching (PSM), comparing the radiological response, pathological response rate, perioperative outcomes, and early recurrence between the two groups. RESULTS: After PSM, 585 patients were included, with 195 and 390 patients comprising the nICT and nCT groups, respectively. The nICT group exhibited a higher objective response rate (79.5% versus [vs.] 59.0%; P<0.001), pathological complete response rate (14.36% vs. 6.41%; P=0.002) and major pathological response rate (39.49% vs. 26.15%; P=0.001) compared with the nCT group. The incidence of surgical complications (17.44% vs. 16.15%, P=0.694) and proportion of perioperative textbook outcomes (80.0% vs. 81.0%; P=0.767) were similar in both groups. The nICT group had a significantly lower proportion of early recurrence than the nCT group (29.7% vs. 40.8%; P=0.047). Furthermore, the multivariable logistic analysis revealed that immunotherapy was an independent protective factor against early recurrence (odds ratio 0.62 [95% CI 0.41-0.92]; P=0.018). No significant difference was found in neoadjuvant therapy drug toxicity between the two groups (51.79% vs. 45.38%; P=0.143). CONCLUSIONS: Compared with nCT, nICT is safe and effective, which significantly enhanced objective and pathological response rates, and reduced the risk for early recurrence among patients with LAGC. TRIAL REGISTRATION: Clinical Trials.gov.

Development and Validation of a Prognostic Model for Postoperative Anastomotic Recurrence in Siewert II or III Adenocarcinomas Without Neoadjuvant Therapy in an East Asian Population.

PURPOSE: Anastomotic recurrence leads to poor prognosis in patients with Siewert II or III adenocarcinoma who undergo radical gastrectomy and do not receive neoadjuvant therapy. We aimed to establish a prognostic model to evaluate the risk of postoperative anastomotic recurrence in patients with Siewert II or III adenocarcinoma who did not receive neoadjuvant therapy. METHODS: We included 366 patients with Siewert II or III adenocarcinoma who were treated with radical gastrectomy without neoadjuvant therapy at Fujian Provincial Hospital (FPH) between 2012 and 2018 as the development cohort. Cox regression was used to verify prognostic factors for anastomotic recurrence, and a nomogram was established. The nomogram was externally validated using a combined cohort of two external centers. Patients were classified into high- or low-risk groups according to the diagnostic threshold and nomogram scores, and recurrence-related survival analysis was analyzed. RESULTS: The average age was 64.6 years, and 285 patients were male. All surgeries were successfully performed (185 open vs 181 laparoscopic). The 3-year anastomotic recurrence rate was significantly lower in the low-risk group (3.5% vs 18.8%, P < 0.001). The predictive performance was verified in the external validation cohort. This model better stratified patient survival than the American Joint Committee on Cancer (AJCC) TNM staging system. CONCLUSIONS: This novel nomogram with surgical margin, postoperative tumor node metastasis (pTNM) stage, and neural invasion as prognostic factors has a significant predictive performance for the risk of anastomotic recurrence after radical gastrectomy in patients with Siewert II or III adenocarcinoma.

Discovery of CDK signature and CDK5 as potential biomarkers for predicting prognosis and immunotherapeutic response in gastric cancer peritoneal metastases.

Gastric cancer peritoneal metastases (GCPM) are a leading cause of death in gastric cancer patients. In this study, we focused on the expression of cyclin-dependent protein kinases (CDK), essential regulators of transcription, metabolism, and cell differentiation, in GCPM. Utilizing the GSE62254 cohort, we established a CDK signature (CDKS) model comprising ten CDK gene family members. Analysis of both the GSE62254 and TCGA cohorts revealed that patients with low CDKS had a worse prognosis compared to those with high CDKS. Furthermore, patients with high CDKS demonstrated positive responses from immunotherapy, as observed in the KIM cohort. We investigated the association between CDKS and the tumor microenvironment, including immune escape mechanisms. Immunohistochemistry analysis revealed a positive correlation between CDK5 and PD-L1 expression in gastric cancer. Furthermore, we found that CDK5 knockdown led to the inhibition of PD-L1 expression in gastric cancer cells. Our findings highlight the potential of CDKS as a prognostic biomarker and an indicator of immunotherapy response in gastric cancer patients. Moreover, our study suggests that targeting CDK5 could provide a new pathway for exploring immunotherapeutic research.

Gastric cancer peritoneal metastasis related signature predicts prognosis and sensitivity to immunotherapy in gastric cancer.

Gastric cancer peritoneal metastases (GCPM) is a leading cause of GC-related death. Early detection of GCPM is critical for improving the prognosis of advanced GC. Differentially expressed genes (DEGs) were identified in the GSE62254 database to distinguish between GCPM and non-GCPM. The gastric cancer peritoneal metastases signature (GCPMs) was developed using DEGs. We analysed the effectiveness of GCPMs as indicators for prognosis, chemotherapy, and immune therapy response in GC patients. Subsequently, we analysed the correlation between GCPMs and immune microenvironment as well as immune escape in GC patients. Random forest model and immunohistochemistry was utilized to identify the crucial genes that can aid in the diagnosis of GCPM. We identified five DEGs and utilized their expression to construct GCPMs. Patients with high GCPMs had a higher likelihood of a poor prognosis, while those with low GCPMs appeared to potentially benefit more from chemotherapy. GCPMs were a dependable marker for predicting the response to immunotherapy. Additionally, GCPMs was found to be significantly linked to stromal score and cancer-associated fibroblasts. SYNPO2 has been identified as the gene with the highest significance in the diagnosis of GCPM. Immunohistochemistry suggests that SYNPO2-positive expression in tumour cells, fibroblasts, inflammatory cell may be associated with promoting peritoneal metastasis in GC. GCPMs have shown to be a promising biomarker for predicting the prognosis and response of GC patients to chemotherapy and immunotherapy. The use of GCPMs for individual tumour evaluation may pave the way for personalized treatment for GC patients in the future.

Radiographical Evaluation of Tumor Immunosuppressive Microenvironment and Treatment Outcomes in Gastric Cancer: A Retrospective, Multicohort Study.

BACKGROUND: The tumor immunosuppressive microenvironment can influence treatment response and outcomes. A previously validated immunosuppression scoring system (ISS) assesses multiple immune checkpoints in gastric cancer (GC) using tissue-based assays. We aimed to develop a radiological signature for non-invasive assessment of ISS and treatment outcomes. METHODS: A total of 642 patients with resectable GC from three centers were divided into four cohorts. Radiomic features were extracted from portal venous-phase CT images of GC. A radiomic signature for predicting ISS (RISS) was constructed using the least absolute shrinkage and selection operator (LASSO) regression method. Moreover, we investigated the value of the RISS in predicting survival and chemotherapy response. RESULTS: The RISS, which consisted of 10 selected features, showed good discrimination of immunosuppressive status in three independent cohorts (area under the curve = 0.840, 0.809, and 0.843, respectively). Multivariate analysis revealed that the RISS was an independent prognostic factor for both disease-free survival (DFS) and overall survival (OS) in all cohorts (all p < 0.05). Further analysis revealed that stage II and III GC patients with low RISS exhibited a favorable response to adjuvant chemotherapy (OS: hazard ratio [HR] 0.407, 95% confidence interval [CI] 0.284-0.584); DFS: HR 0.395, 95% CI 0.275-0.568). Furthermore, the RISS could predict prognosis and select stage II and III GC patients who could benefit from adjuvant chemotherapy independent of microsatellite instability status and Epstein-Barr virus status. CONCLUSION: The new, non-invasive radiomic signature could effectively predict the immunosuppressive status and prognosis of GC. Moreover, the RISS could help identify stage II and III GC patients most likely to benefit from adjuvant chemotherapy and avoid overtreatment.

Priority of lymph node dissection for advanced esophagogastric junction adenocarcinoma with the tumor center located below the esophagogastric junction.

To clarify the priority of lymph node dissection (LND) in advanced Siewert type II and III AEG, in which the center of the tumor is located below the esophagogastric junction (EGJ).Data in 395 patients with advanced Siewert type II or III AEG was analyzed retrospectively. The index of estimated benefit from LND (IEBLD) was used to evaluate the efficacy of LND for each nodal station.The mean number of dissected LNs did not differ significantly between patients with type II and III AEG, nor did the mean number of retrieved LNs at each station significantly differ between the 2 groups. According to the IEBLD, the dissection of parahiatal LNs (No.19 and 20) and LNs along the distal portion of the stomach (No.5, 6, and 12a) seemed unlikely to be beneficial, whereas the dissection of Nos.1-3, 7, 9 and 11p yielded high therapeutic benefit (IEBLD>3.0) in both groups. The IEBLDs of No.4d, 8a, and 10 were much higher in type III than in type II AEG cases. No.10 LND may improve survival for type III AEG cases (IEBLD = 2.9), especially for subgroups with primary tumors invading the serosa layer, undifferentiated cancers, macroscopic type 3-4 tumors and tumors ≥50 mm in size (all IEBLDs > 4.0).For advanced AEG located below the EGJ, the dissection of paracardial LNs, lesser curvature LNs, and LNs around the celiac axis would promote higher survival benefits regardless of the Siewert subtype. Patients with type III AEG, especially those with serosa-invasive tumors, undifferentiated tumors, macroscopic type 3-4 tumors and tumors ≥50 mm in size may obtain relatively higher survival benefits from No. 10 lymphadenectomy.

Laparoscopic-assisted versus open total gastrectomy for Siewert type II and III esophagogastric junction carcinoma: a propensity score-matched case-control study.

BACKGROUND: Few studies have evaluated the outcomes of laparoscopic-assisted total gastrectomy (LATG) for Siewert type II and III adenocarcinoma of the esophagogastric junction (AEG). Thus, aim of this study was to investigate the surgical outcomes of LATG for Siewert type II and III AEG. METHODS: Clinical data for 700 Siewert type II and III AEG patients were analyzed retrospectively. The short- and long-term outcomes were compared between the matched groups using a propensity score matching method. RESULTS: Before matching, the comorbidities, Siewert classifications and tumor invasion depths significantly differed between the LATG and open total gastrectomy (OTG) groups. After matching, the clinicopathologic characteristics were well balanced between the two groups. In addition, after matching, decreases in the operative time, amount of blood loss, time to resumption of a semifluid diet, and length of hospital stay and an increased number of lymph nodes (LNs) retrieved were observed in the LATG group compared with the OTG group. Further, a significantly higher 3-year overall survival rate (81.3 vs 66.4%; P = 0.011) and disease-free survival rate (77.5 vs 63.8%; P = 0.040) were observed for the Siewert type II AEG patients in the LATG group compared with those in the OTG group; however, the survival rates were similar for the Siewert type III AEG patients in the two groups (P = 0.853 and P = 0.844, respectively). CONCLUSIONS: LATG is associated with better short-term outcomes for Siewert type II and III AEG. In addition, it may result in an increased number of retrieved LNs and better long-term survival for Siewert type II AEG patients in particular.

Should Splenic Hilar Lymph Nodes be Dissected for Siewert Type II and III Esophagogastric Junction Carcinoma Based on Tumor Diameter?: A Retrospective Database Analysis.

The aim of the study is to identify the value of a spleen-preserving No. 10 lymphadenectomy (SPL) for Siewert type II/III adenocarcinoma of the esophagogastric junction (AEG).From January 2007 to June 2014, 694 patients undergoing radical total gastrectomy for Siewert type II/III AEG were analyzed. Oncologic outcomes were compared between SPL and no SPL (No. 10D+ and No. 10D-) groups.The incidence of No. 10 lymph node metastasis (LNM) was 12.3%. No significant differences in the incidence of No. 10 LNM were found between Siewert type II AEG with tumor diameters of <4 cm and ≥4 cm (P = 0.071). However, Siewert type III AEG with a tumor diameter ≥4 cm showed a significantly higher frequency of No. 10 LNM compared with a tumor diameter <4 cm (P < 0.001). The No. 10D+ group had superior 3-year overall survival (OS) and disease-free survival (DFS) rates compared with the No. 10D- group (P = 0.030 and P = 0.005, respectively). For patients with Siewert type II and type III AEG with a tumor diameter <4 cm, the 3-year OS and DFS rates were similar between the 2 groups. However, the No. 10D+ group had better 3-year OS (66.6% vs 51.1%, P = 0.019) and DFS (63.2% vs 45.9%, P = 0.007) rates for Siewert type III AEG with a tumor diameter ≥4 cm. A multivariate Cox regression showed that SPL was an independent prognostic factor in Siewert type III AEG with a tumor diameter ≥4 cm.SPL may improve the prognosis of Siewert type III AEG with a tumor diameter ≥4 cm, whereas SPL may be omitted without decreasing survival in patients with Siewert type II or type III AEG with a tumor diameter <4 cm.