Risk Assessment and Preventive Treatment for Peritoneal Recurrence Following Radical Resection for Gastric Cancer

As the most common recurrence pattern after radical gastric cancer resection, peritoneal recurrence is a major cause of mortality, which affects the prognosis of patients to a very large extent. Peritoneal status and risk of peritoneal recurrence can be evaluated by peritoneal lavage cytology, photodynamic diagnosis, imaging examination, and pathologic analysis. Presently, there is no standard approach for preventing peritoneal recurrence after radical surgery; furthermore, controversies exist regarding the effects of some preventive methods. Among the preventive methods, there are high expectations about the potential of preoperative therapy, surgical skill improvement, hyperthermic intraperitoneal chemotherapy, and postoperative treatment to reduce the incidence of peritoneal recurrence after radical gastrectomy. This study aimed to analyze the results of previous studies on the risk assessment and preventive methods of peritoneal recurrence after radical gastrectomy in recent years. We hope to provide references for better approach to clinical diagnosis and treatment strategies for peritoneal recurrence after radical gastrectomy.

Effect of HIPEC on Peritoneal Recurrence in Peritoneal Metastasis Treated With Cytoreductive Surgery: A Systematic Review

BackgroundPeritoneal metastasis (PM) is a late-stage manifestation of intra-abdominal malignancies. The current standard of care indicates that cure can only be achieved with cytoreductive surgery (CRS) which is often indicated with concurrent adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC). However, the utility of HIPEC within subsets of PM is not fully understood. We seek to compare the effectiveness of HIPEC in improving peritoneal recurrence rates in PM of different origins.MethodsWe conducted a systematic review of trials on the PubMed, EMBASE, and Cochrane databases, last searched in August 2021. Biases were assessed using the Cochrane Collaboration’s tool for assessing the risk of bias in randomized trials as well as the Methodological Index for Non-Randomized Studies (MINORS) framework.Results7 gastric PM studies, 3 ovarian PM studies, and 3 colorectal PM studies were included. Recurrence-free survival was improved in the HIPEC + CRS cohort in 5 gastric trials but only 1 ovarian trial and none of colorectal origin.DiscussionOur findings indicate decent effectiveness of HIPEC in gastric PM, but limited utility in ovarian and colorectal PM. Limitations in the current literature are attributed to the paucity of data available, a lack of homogeneity and consideration of novel and personalised treatment regimens. We implore for further studies to be conducted with a focus on patient selection and stratification, and suggest a reframing of approach towards modern molecular and targeted therapeutic options in future studies of HIPEC.Systematic Review Registrationhttps://www.researchregistry.com/browse-the-registry#registryofsystematicreviewsmeta-analyses/registryofsystematicreviewsmeta-analysesdetails/60c1ffff0c1b78001e8efbe3/, identifier reviewregistry1166.

Is Prophylactic Hyperthermic Intraperitoneal Chemotherapy Beneficial to The Long-Term Survival of Patients After Radical Gastric Cancer Surgery: A Systematic Review and Meta-analysis

Background: Hyperthermic intraperitoneal chemotherapy (HIPEC) has been proven to improve the survival rate of gastric cancer and reduce peritoneal recurrence. We aimed to evaluate the effectiveness and safety of prophylactic HIPEC after radical gastric cancer surgery in this study.Methods: Researchers searched for studies published in PubMed, Embase, Web of science, Scopus, Cochrane, Clinicalkey databases and Microsoft Academic databases to identify studies that examine the impact of prophylactic HIPEC on the survival, recurrence and adverse events of patients undergoing radical gastric cancer surgery. RevMan 5.3 was used to analyze the results and risk of bias. The PROSERO registration number is CRD42021262016.Results: This meta-analysis included 19 studies with a total of 2097 patients, 12 of which are RCTs. The results showed that the 1-,3-and 5-year overall survival rate was significantly favorable to HIPEC (OR=5.10,2.47,1.96 respectively). Compared with the control group, the overall recurrence rate and peritoneal recurrence rate of the HIPEC group were significantly lower (OR=0.43,0.26 respectively). Significantly favorable to the control group in terms of renal dysfunction and pulmonary dysfunction complications(OR=2.44,6.03 respectively). Regarding the causes of death due to postoperative recurrence: liver recurrence, lymph node and local recurrence and peritoneal recurrence, the overall effect is not significantly different (OR=0.81,1.19,0.37 respectively).Conclusions: 1-,3-and 5-year overall survival follow-up can be incremented by the prophylactic HIPEC, and which can significantly reduce the overall recurrence rate and peritoneal recurrence rate. HIPEC can cause significant pulmonary dysfunction and renal dysfunction complications. No difference has been found in the deaths due to recurrence after surgery.

The clinicopathologic significance of Tks5 expression of peritoneal mesothelial cells in gastric cancer patients

Background Gastric cancer (GC) patients frequently develop peritoneal metastasis. Recently, it has been reported that peritoneal mesothelial cells (PMCs) activated by GC cells acquire a migratory capacity and promote GC cell invasion. The invasiveness of PMCs reportedly depends on the activity of Tks5, an adaptor protein required for invadopodia formation. However, the relationship between clinicopathologic features and Tks5 expression in PMCs has been poorly documented. In this study, we evaluated the clinicopathologic significance of the Tks5 expression of PMCs in GC patients. Materials and methods A total of 110 GC patients who underwent gastrectomy were enrolled in this study. Tks5 expressions in PMCs from the greater omentum, lesser omentum and retroperitoneum were evaluated by immunohistochemistry. We analyzed the correlation between Tks5 expressions in PMCs and the patients’ clinicopathologic features. Results Tks5 expression was found in 71 (64.5%) of the 110 patients, while 39 (35.5%) were Tks5-negative. Tks5 positivity was significantly (p = 0.038) associated with a greater tumor depth (i.e., T3/4 compared with T1/T2). Peritoneal recurrence was found in 12 of 98 cases within 3 years of surgery. The 3-year peritoneal recurrence-free survival (PRFS) rate in Tks5-positive cases was significantly poorer than that in Tks5-negative cases (80.1% vs 97.4%, p = 0.024). Multivariate analysis revealed that Tks5 positivity and lymph node metastasis were independent factors for PRFS. Conclusion Tks5 is frequently expressed in PMCs in advanced-stage gastric cancer. Tks5 might be a useful predictor for peritoneal recurrence in GC patients.

Intraperitoneal Chemotherapy Using Fluorouracil Implants Combined With Radical Resection and Postoperative Adjuvant Chemotherapy for Stage III Gastric Cancer: A Multi-Center, Randomized, Open-Label, Controlled Clinical Study

BackgroundReducing peritoneal recurrence after radical surgery is an important choice to improve the prognosis of patients with advanced gastric cancer. Intraoperative intraperitoneal chemotherapy has the potential to be a promising treatment strategy. In the present study, we conducted a multi-center, randomized, controlled clinical study to evaluate the efficacy and safety of intraoperative intraperitoneal chemotherapy using sustained-release fluorouracil implants plus radical gastrectomy and adjuvant chemotherapy for cTNM stage III gastric cancer.MethodsThe patients were randomized into intraperitoneal chemotherapy group (sustained-release fluorouracil implants administration after standard D2 radical gastrectomy, and followed by XELOX adjuvant chemotherapy) and control group (standard D2 radical gastrectomy, and followed by XELOX adjuvant chemotherapy). A total of 122 patients from three centers were enrolled from September 2015 to February 2017.ResultsOne hundred and two eligible patients completed the treatment course. The median follow-up time was 41.7 months (36.1–52.9 months). The 3-year progression-free survival rate and overall survival of patients in the intraperitoneal chemotherapy group were 43.9% and 49.1%, respectively, which were significantly better than those of the control group, 31.0% and 38.4%. In the intraperitoneal chemotherapy group, the number of cases with peritoneal recurrence was significantly less than that of the control group, 9 cases (17.3%) vs. 19 cases (44.2%). There were neither significant differences between the groups in the incidence of hematogenous metastasis, lymph node metastasis, nor local metastasis.ConclusionFor cTNM stage III gastric cancer, intraoperative sustained-release fluorouracil implants after radical resection combined with postoperative adjuvant chemotherapy, could significantly reduce the risk of peritoneal recurrence and prolong PFS.Clinical Trial Registrationhttps://clinicaltrials.gov/, identifier (NCT02269904).

Immune Landscape of Gastric Carcinoma Tumor Microenvironment Identifies a Peritoneal Relapse Relevant Immune Signature

BackgroundGastric cancer (GC) still represents the third leading cause of cancer-related death worldwide. Peritoneal relapse (PR) is the most frequent metastasis occurring among patients with advanced gastric cancer. Increasingly more evidence have clarified the tumor immune microenvironment (TIME) may predict survival and have clinical significance in GC. However, tumor-transcriptomics based immune signatures derived from immune profiling have not been established for predicting the peritoneal recurrence of the advanced GC.MethodsIn this study, we depict the immune landscape of GC by using transcriptome profiling and clinical characteristics retrieved from GSE62254 of Gene Expression Omnibus (GEO). Immune cell infiltration score was evaluated via single-sample gene set enrichment (ssGSEA) analysis algorithm. The least absolute shrinkage and selection operator (LASSO) Cox regression algorithm was used to select the valuable immune cells and construct the final model for the prediction of PR. The receiver operating characteristic (ROC) curve and the Kaplan-Meier curve were used to check the accuracy of PRIs. Gene Set Enrichment Analysis (GSEA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed to explore the molecular pathways associated with PRIs.ResultsA peritoneal recurrence related immune score (PRIs) with 10 immune cells was constructed. Compared to the low-PRIs group, the high-PRIs group had a greater risk. The upregulation of the focal adhesion signaling was observed in the high-PRIs subtype by GSEA and KEGG. Multivariate analysis found that both in the internal training cohort and the internal validation cohort, PRIs was a stable and independent predictor for PR. A nomogram that integrated clinicopathological features and PRIs to predict peritoneal relapse was constructed. Subgroup analysis indicated that the PRIs could obviously distinguish peritoneal recurrence in different molecular subtypes, pathological stages and Lauren subtypes, in which PRIs of Epithelial-Mesenchymal Transitions (EMT) subtype, III-IV stage and diffuse subtype are higher respectively.ConclusionOverall, we performed a comprehensive evaluation of the immune landscape of GC and constructed a predictive PR model based on the immune cell infiltration. The PRIs represents novel promising feature of predicting peritoneal recurrence of GC and sheds light on the improvement of the personalized management of GC patients after surgery.