Bile acids serve as endogenous antagonists of the Leukemia inhibitory factor (LIF) receptor in oncogenesis.

The leukemia inhibitory factor (LIF) is member of interleukin (IL)-6 family of cytokines involved immune regulation, morphogenesis and oncogenesis. In cancer tissues, LIF binds a heterodimeric receptor (LIFR), formed by a LIFRß subunit and glycoprotein(gp)130, promoting epithelial mesenchymal transition and cell growth. Bile acids are cholesterol metabolites generated at the interface of host metabolism and the intestinal microbiota. Here we demonstrated that bile acids serve as endogenous antagonist to LIFR in oncogenesis. The tissue characterization of bile acids content in non-cancer and cancer biopsy pairs from gastric adenocarcinomas (GC) demonstrated that bile acids accumulate within cancer tissues, with glyco-deoxycholic acid (GDCA) functioning as negative regulator of LIFR expression. In patient-derived organoids (hPDOs) from GC patients, GDCA reverses LIF-induced stemness and proliferation. In summary, we have identified the secondary bile acids as the first endogenous antagonist to LIFR supporting a development of bile acid-based therapies in LIF-mediated oncogenesis.

A pragmatic approach improves the clinical management of stage IV gastric cancer: Comparison between the Meta-Gastro results and the GIRCG's retrospective series.

INTRODUCTION: The Italian Research Group for Gastric Cancer developed a prospective database about stage IV gastric cancer, to evaluate how a pragmatic attitude impacts the management of these patients. MATERIALS AND METHODS: We prospectively collected data about metastatic gastric cancer patients thanks to cooperation between radiologists, oncologists and surgeons and we analyzed survival and prognostic factors, comparing the results to those obtained in our retrospective study. RESULTS: Three-hundred and eighty-three patients were enrolled from 2018 to September 2022. We observed a higher percentage of laparoscopic exploration with peritoneal lavage in the prospective cohort. In the registry only 3.6 % of patients was submitted to surgery without associated chemotherapy, while in the retrospective population 44.3 % of patients were operated on without any chemotherapy. At univariate and multivariate analyses, the different metastatic sites did not show any survival differences among each other (OS 20.0 vs 16.10 vs 16.7 months for lymphnodal, peritoneal and hepatic metastases, respectively), while the number of metastatic sites and the type of treatment showed a statistical significance (OS 16,7 vs 13,0 vs 4,5 months for 1, 2 and 3 different metastatic sites respectively, p < 0.001; 24,2 vs 12,0 vs 2,5 months for surgery with/without chemotherapy, chemotherapy alone and best supportive treatment respectively, p < 0.001). CONCLUSIONS: Our data highlight that the different metastatic sites did not show different survivals, but survival is worse in case of multiple localization. In patients where a curative resection can be achieved, acceptable survival rates are possible. A better diagnostic workup and a more accurate staging impact favorably upon survival.

Is Systemic Chemotherapy Useful in Patients Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Colorectal Peritoneal Metastases? A Propensity-Score Analysis.

PURPOSE: Multimodal treatment of colorectal (CRC) peritoneal metastases (PM) includes systemic chemotherapy (SC) and surgical cytoreduction (CRS), eventually with hyperthermic intraperitoneal chemotherapy (HIPEC), in select patients. Considering lack of clear guidelines, this study was designed to analyze the role of chemotherapy and its timing in patients treated with CRS-HIPEC. METHODS: Data from 13 Italian centers with PM expertise were collected by a collaborative group of the Italian Society of Surgical Oncology (SICO). Clinicopathological variables, SC use, and timing of administration were correlated with overall survival (OS), disease-free survival (DFS), and local (peritoneal) DFS (LDFS) after propensity-score (PS) weighting to reduce confounding factors. RESULTS: A total of 367 patients treated with CRS-HIPEC were included in the propensity-score weighting. Of the total patients, 19.9% did not receive chemotherapy within 6 months of surgery, 32.4% received chemotherapy before surgery (pregroup), 28.9% after (post), and 18.8% received both pre- and post-CRS-HIPEC treatment (peri). SC was preferentially administered to younger (p = 0.02) and node-positive (p = 0.010) patients. Preoperative SC is associated with increased rate of major complications (26.9 vs. 11.3%, p = 0.0009). After PS weighting, there were no differences in OS, DFS, or LDFS (p = 0.56, 0.50, and 0.17) between chemotherapy-treated and untreated patients. Considering SC timing, the post CRS-HIPEC group had a longer DFS and LDFS than the pre-group (median DFS 15.4 vs. 9.8 m, p = 0.003; median LDFS 26.3 vs. 15.8 m, p = 0.026). CONCLUSIONS: In patients with CRC-PM treated with CRS-HIPEC, systemic chemotherapy was not associated with overall survival benefit. The adjuvant schedule was related to prolonged disease-free intervals. Additional, randomized studies are required to clarify the role and timing of systemic chemotherapy in this patient subset.

The leukemia inhibitory factor regulates fibroblast growth factor receptor 4 transcription in gastric cancer.

PURPOSE: The gastric adenocarcinoma (GC) represents the third cause of cancer-related mortality worldwide, and available therapeutic options remain sub-optimal. The Fibroblast growth factor receptors (FGFRs) are oncogenic transmembrane tyrosine kinase receptors. FGFR inhibitors have been approved for the treatment of various cancers and a STAT3-dependent regulation of FGFR4 has been documented in the H.pylori infected intestinal GC. Therefore, the modulation of FGFR4 might be useful for the treatment of GC. METHODS: To investigate wich factors could modulate FGFR4 signalling in GC, we employed RNA-seq analysis on GC patients biopsies, human patients derived organoids (PDOs) and cancer cell lines. RESULTS: We report that FGFR4 expression/function is regulated by the leukemia inhibitory factor (LIF) an IL-6 related oncogenic cytokine, in JAK1/STAT3 dependent manner. The transcriptomic analysis revealed a direct correlation between the expression of LIFR and FGFR4 in the tissue of an exploratory cohort of 31 GC and confirmed these findings by two external validation cohorts of GC. A LIFR inhibitor (LIR-201) abrogates STAT3 phosphorylation induced by LIF as well as recruitment of pSTAT3 to the promoter of FGFR4. Furthermore, inhibition of FGFR4 by roblitinib or siRNA abrogates STAT3 phosphorylation and oncogentic effects of LIF in GC cells, indicating that FGFR4 is a downstream target of LIF/LIFR complex. Treating cells with LIR-201 abrogates oncogenic potential of FGF19, the physiological ligand of FGFR4. CONCLUSIONS: Together these data unreveal a previously unregnized regulatory mechanism of FGFR4 by LIF/LIFR and demonstrate that LIF and FGF19 converge on the regulation of oncogenic STAT3 in GC cells.

Palliative short-course radiotherapy (RAPASH study) in patients with rectal cancer.

Background: Palliative radiation therapy (RT) is used to treat symptomatic rectal cancer although clinical benefits and toxicities are poorly documented. There is no consensus about the optimal RT regimen and clinical practice undergoes significant changes. Our aim was to evaluate the efficacy and toxicity of short-course (SC) RT in this setting of patients. Materials and methods: Charts from patients with locally advanced disease not candidates for standard treatment or with symptomatic metastatic rectal cancer treated with SCRT (25 Gy/5 fractions in 5 consecutive days) were retrospectively reviewed. Clinical outcome measures were symptomatic response rate and toxicity. Results: From January 2007 to December 2017, 59 patients (median age 80 years) received SCRT; 53 were evaluable. The median follow-up was 8 months (range, 1-70). Clinical response to RT for bleeding, pain and tenesmus was 100%, 95% and 89%, respectively. The compliance with the treatment was 100% and no patient experienced acute severe (≥ grade 3) toxicities. Median time to symptoms recurrence was 11 months (range 3-69). Globally, the median overall survival was 12 months. Conclusions: SCRT is a safe and effective regimen in symptomatic rectal cancer and may be considered the regimen of choice for standard treatment in unfit patients.

Prognostic Survival Significance of Signet Ring Cell (SRC) Gastric Cancer: Retrospective Analysis from a Single Western Center.

INTRODUCTION: Signet ring cell carcinoma accounts for 35% to 45% of all gastric cancer. Despite the acknowledgment of its more aggressive pathological features, various controversies surrounding this topic still exist. Thus, we investigate the clinical pathological characteristics and survival prognostic significance of signet ring cell components in patients affected by gastric cancer. METHODS: From January 2004 to December 2020, in a retrospective study, we enrolled 404 patients with gastric cancer who were curatively treated in our department. The male-to-female ratio was 249/142, and the median age was 75 (range 37-94). We dichotomized patients into two groups (75 patients vs. 316 patients) based on the signet ring cell presence; according to preoperative, operative, and postoperative characteristics, we performed a univariate and multivariate analysis for overall survival. RESULTS: Signet ring cell carcinoma indicated an increasing incidence trend over the time analyzed. Overall median survival of signet ring cell and non-signet ring cell carcinoma were, respectively, 16 vs. 35 months, p < 0.05. In early gastric cancer, the prognosis of the signet ring cell is better than that of the non-signet ring cell, as opposed to advanced cancer. Among the entire population in the multivariate analysis, the only independent factors were preoperative serum albumin level, complete surgical resection, level of lymphadenectomy, and pathological stage. Recurrence occurred more frequently in patients affected by signet ring cell, but in our data, we could not identify a peculiar site of recurrence. CONCLUSIONS: Signet ring cell carcinoma has a specific oncogenetic phenotype and treatment resistance heterogeneity; however, it is not always associated with poor prognosis. According to our results, a radical surgical procedure associated with an adequate lymphadenectomy should be advocated to improve patients survival. Gastric cancer patients with signet ring cell components should draw clinicians' attention.

Evaluation of peritoneal Carcinoembryonic Antigen as a survival prognostic factor in gastric cancer patients: a single western center experience.

The aim of this study is to define the importance of peritoneal CEA (pCEA) as a prognostic factor of overall survival (OS) and disease-free survival (DFS) in gastric cancer (GC) patients surgically treated with a curative intent In our department. A total of 64 patients affected by gastric cancer with intraoperatively measurement of CEA on peritoneal lavage were enrolled in the study. Patients were divided into two groups: (A) the peritoneal lavage CEA ( -) with CEA < 0.5 ng/ml and (B) the peritoneal lavage CEA ( +) with CEA ≥ 0.5 ng/ml. Then we analyzed OS and DFS of the two groups correlating them to others clinico-pathological features. Furthermore, we investigated the correlation between pCEA and peritoneal cytology. We demonstrated a strong significant difference in OS and in DFS in CEA ( +) patients. We emphasized that pCEA had a strong survival impact, in both OS and DFS, in selected patients affected by diffuse histotype GC (p = 0.0048 and p = 0.0030 respectively), stage III (p = 0.015 and p = 0.021, respectively) and distal gastric cancer (p = 0.0036 and p = 0.0017, respectively). There is a strong need to recognize prognostic factors that can help clinicians to stratify patients at high risk to develop post-surgical recurrences and moreover to recognize who could benefit from an aggressive surgical treatment of cytoreductive surgery and intra-peritoneal chemotherapy.pCEA is a good predictor of survival in advanced gastric cancer and could discriminate which patients need a more accurate follow-up program and an intensive therapeutic strategy.

Rationale in the Use of Adjuvant Chemotherapy in pT3N0M0 Gastric Cancer Resected Patients. Comment on Chen et al. Prognostic Factors and the Role of Adjuvant Chemotherapy in Pathological Node-Negative T3 Gastric Cancer. J. Pers. Med. 2023, 13, 553.

I read with great interest the well-written and well-made study by Yi-Fu Chen et al. recently published in the "Journal of Personalized Medicine" [...].

Gastric Cancer (GC) with Peritoneal Metastases (PMs): An Overview of Italian PSM Oncoteam Evidence and Study Purposes.

Gastric cancer (GC) continues to be one of the leading types of malignancies worldwide, despite an ongoing decrease in incidence. It is the fifth most frequent type of cancer in the world and the fourth leading cause of cancer death. Peritoneal metastases (PMs) occur in 20-30% of cases during the natural history of the disease. Systemic chemotherapy (SC) is undoubtedly the standard of care for patients with GC and PMs. However, with the development of highly effective regimens (SC combined with intraperitoneal chemotherapy), significant tumor shrinkage has been observed in many patients with synchronous GC and PMs, allowing some to undergo curative resection "conversion surgery" with long-term survival. In recent years, there has been growing interest in intraperitoneal chemotherapy for PMs, because the reduced drug clearance associated with the peritoneal/plasma barrier allows for direct and prolonged drug exposure with less systemic toxicity. These procedures, along with other methods used for peritoneal surface malignancies (PSMs), can be used in GCs with PMs as neoadjuvant chemotherapy or adjuvant treatments after radical surgery or as palliative treatments delivered either laparoscopically or-more recently-as pressurized intraperitoneal aerosol chemotherapy. The great heterogeneity of patients with stage IV gastric cancer did not allow us to carry out a systemic review; therefore, we limited ourselves to providing readers with an overview to clarify the indications and outcomes of integrated treatments for GCs with PMs by analyzing reports from the international clinical literature and the specific experiences of our oncoteam.

Consequences of the COVID-19 pandemic on the diagnosis and treatment of gastric cancer in referral centers in Italy.

BACKGROUND: The coronavirus pandemic had a major impact in Italy. The Italian health system's re-organization to face the emergency may have led to significant consequences especially in the diagnosis and treatment of malignancies. This study aimed to assess the impact of the pandemic in the diagnosis and treatment of gastric cancer in nine Gruppo Italiano RIcerca Cancro Gastrico (GIRCG) centers. METHODS: All patients assessed for gastric adenocarcinoma at nine GIRCG centers between January 2019 and November 2020 were included. Patients were grouped according to the date of "patient 1's" diagnosis in Italy: preCOVID versus COVID. Clinico-pathological and outcome differences between the two groups were analyzed. RESULTS: A total of 632 patients were included in the analysis (205 in the COVID group). The cT4 weighted ratios were higher in 2020 from April to September, with the greatest differences in May, August and September. The cM+ weighted ratio was significantly higher in July 2020. The mean number of gastrectomies had the greatest reduction in March and May 2020 compared with 2019. The median times from diagnosis to chemotherapy, to complete diagnostic work-up or to operation were longer in 2019. The median time from the end of chemotherapy to surgery was 17 days longer in the preCOVID group. CONCLUSIONS: A greater number of advanced or metastatic cases were diagnosed after the spread of SARS-CoV-2 infection, especially after the "full lockdown" periods. During the pandemic, once gastric cancer patients were referred to one of the centers, a shorter time to complete the diagnostic work-up or to address them to the best treatment option was required.

Clinical outcomes of patients with complicated post-operative course after gastrectomy for cancer: a GIRCG study using the GASTRODATA registry.

Gastrectomy for gastric cancer is still performed in Western countries with high morbidity and mortality. Post-operative complications are frequent, and effective diagnosis and treatment of complications is crucial to lower the mortality rates. In 2015, a project was launched by the EGCA with the aim of building an agreement on list and definitions of post-operative complications specific for gastrectomy. In 2018, the platform www.gastrodata.org was launched for collecting cases by utilizing this new complication list. In the present paper, the Italian Research Group for Gastric Cancer endorsed a collection of complicated cases in the period 2015-2019, with the aim of investigating the clinical pictures, diagnostic modalities, and treatment approaches, as well as outcome measures of patients experiencing almost one post-operative complication. Fifteen centers across Italy provided 386 cases with a total of 538 complications (mean 1.4 complication/patient). The most frequent complications were non-surgical infections (gastrointestinal, pulmonary, and urinary) and anastomotic leaks, accounting for 29.2% and 17.3% of complicated patients, with a median Clavien-Dindo score of II and IIIB, respectively. Overall mortality of this series was 12.4%, while mortality of patients with anastomotic leak was 25.4%. The clinical presentation with systemic septic signs, the timing of diagnosis, and the hospital volume were the most relevant factors influencing outcome.

A national survey on the current status of minimally invasive gastric practice on behalf of GIRCG.

Italian Research Group for Gastric Cancer (GIRCG), during the 2013 annual Consensus Conference to gastric cancer, stated that laparoscopic or robotic approach should be limited only to early gastric cancer (EGC) and no further guidelines were currently available. However, accumulated evidences, mainly from eastern experiences, have supported the application of minimally invasive surgery also for locally advanced gastric cancer (AGC). The aim of our study is to give a snapshot of current surgical propensity of expert Italian upper gastrointestinal surgeons in performing minimally invasive techniques for the treatment of gastric cancer in order to answer to the question if clinical practice overcome the recommendation. Experts in the field among the Italian Research Group for Gastric Cancer (GIRCG) were invited to join a web 30-item survey through a formal e-mail from January 1st, 2020, to June 31st, 2020. Responses were collected from 46 participants out of 100 upper gastrointestinal surgeons. Percentage of surgeons choosing a minimally invasive approach to treat early and advanced gastric cancer was similar. Additionally analyzing data from the centers involved, we obtained that the percentage of minimally invasive total and partial gastrectomies in advanced cases augmented with the increase of surgical procedures performed per year (p = 0.02 and p = 0.04 respectively). It is reasonable to assume that there is a widening of indications given by the current national guideline into clinical practice. Propensity of expert Italian upper gastrointestinal surgeons was to perform minimally invasive surgery not only for early but also for advanced gastric cancer. Of interest volume activity correlated with the propensity of surgeons to select a minimally invasive approach.

External validation of COMPASS and BIOSCOPE prognostic scores in colorectal peritoneal metastases treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC).

INTRODUCTION: The selection of patients undergoing cytoreductive- surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is crucial. BIOSCOPE and COMPASS are prognostic scores designed to stratify survival into four classes according to clinical and pathological features. The purpose of this study is to analyze the prognostic role of these scores using a large cohort of patients as an external reference. METHODS: Overall survival analysis was performed using Log-Rank and Kaplan-Meier curves for each score. The probability of survival at 12, 36, and 60 months was tested using receiver operating characteristic (ROC) curves to determine sensitivity and specificity. RESULTS: From the validation cohort of 437 patients, the analysis included 410 patients in the COMPASS group and 364 patients in the BIOSCOPE group (100% data completeness). We observed a different patient distribution between classes (high-risk for BIOSCOPE compared to COMPASS, p = 0.0001). Nevertheless, both COMPASS and BIOSCOPE effectively stratified overall survival (Log-Rank, p = 0.0001 in both cases), with a lack of discrimination between COMPASS classes II and III (p = n.s.). COMPASS at 12 m and BIOSCOPE at 60 m showed the best performance in terms of survival prediction (AUC of 0.82 and 0.81). The specificity of the two tests is good (median 81.3%), whereas sensibility is quite low (median 64.2%). CONCLUSION: Following external validation in a large population of patients with CRC-PM who are eligible for surgery, the COMPASS and BIOSCOPE scores exhibit high inter-test variability but effectively stratify cancer-related mortality risk. While the quality of the scores is similar, BIOSCOPE shows better inter-tier differentiation, suggesting that tumor molecular classification could improve test discrimination capability. More powerful stratification scores with the inclusion of novel predictors are needed.

Oligometastatic Gastric Cancer: Clinical Data from the Meta-Gastro Prospective Register of the Italian Research Group on Gastric Cancer.

BACKGROUND: Interest in the field of metastatic gastric cancer has grown in recent years, and the identification of oligometastatic patients plays a critical role as it consents to their inclusion in multimodal treatment strategies, which include systemic therapy but also surgery with curative intent. To collect sound clinical data on this subject, The Italian Research Group on Gastric Cancer developed a prospective multicentric observational register of metastatic gastric cancer patients called META-GASTRO. METHODS: Data on 383 patients in Meta-Gastro were mined to help our understanding of oligometastatic, according to its double definition: quantitative/anatomical and dynamic. RESULTS: the quantitative/anatomical definition applies to single-site metastases independently from the metastatic site (p < 0.001) to peritoneal metastases with PCI ≤ 12 (p = 0.009), to 1 or 2 hepatic metastases (p = 0.024) and nodal metastases in station 16 (p = 0.002). The dynamic definition applies to a percentage of cases variable according to the metastatic site: 8%, 13.5 and 23.8% for hepatic, lymphatic and peritoneal sites, respectively. In all cases, the OS of patients benefitting from conversion therapy was similar to those of cases deemed operable at diagnosis and operated after neoadjuvant chemotherapy. CONCLUSIONS: META-GASTRO supports the two-fold definition of oligometastatic gastric cancer: the quantitative/anatomical one, which accounts for 30% of our population, and the dynamic one, observed in 16% of our cases.

Next-Generation Sequencing Analysis of Gastric Cancer Identifies the Leukemia Inhibitory Factor Receptor as a Driving Factor in Gastric Cancer Progression and as a Predictor of Poor Prognosis.

Gastric cancer (GC) is the third cause of cancer-related mortality worldwide. Nevertheless, because GC screening programs are not cost-effective, most patients receive diagnosis in the advanced stages, when surgical options are limited. Peritoneal dissemination occurs in approximately one-third of patients with GC at the diagnosis and is a strong predictor of poor outcome. Despite the clinical relevance, biological and molecular mechanisms underlying the development of peritoneal metastasis in GC remain poorly defined. Here, we report results of a high-throughput sequencing of transcriptome expression in paired samples of non-neoplastic and neoplastic gastric samples from 31 patients with GC with or without peritoneal carcinomatosis. The RNA-seq analysis led to the discovery of a group of highly upregulated or downregulated genes, including the leukemia inhibitory factor receptor (LIFR) and one cut domain family member 2 (ONECUT2) that were differentially modulated in patients with peritoneal disease in comparison with patients without peritoneal involvement. Both LIFR and ONECUT2 predicted survival at univariate statistical analysis. LIFR and its major ligand LIF belong to the interleukin-6 (IL-6) cytokine family and have a central role in immune system regulation, carcinogenesis, and dissemination in several human cancers. To confirm the mechanistic role of the LIF/LIFR pathway in promoting GC progression, GC cell lines were challenged in vitro with LIF and a LIFR inhibitor. Among several GC cell lines, MKN45 cells displayed the higher expression of the receptor, and their exposure to LIF promotes a concentration-dependent proliferation and epithelial-mesenchymal transition (EMT), as shown by modulation of relative expression of E-cadherin/vimentin along with JAK and STAT3 phosphorylation and acquisition of a migratory phenotype. Furthermore, exposure to LIF promoted the adhesion of MKN45 cells to the peritoneum in an ex vivo assay. These effects were reversed by the pharmacological blockade of LIFR signaling. Together, these data suggest that LIFR might have a major role in promoting disease progression and peritoneal dissemination in patients with GC and that development of LIF/LIFR inhibitors might have a role in the treatment of GC.

GLP-1 Mediates Regulation of Colonic ACE2 Expression by the Bile Acid Receptor GPBAR1 in Inflammation.

BACKGROUND & AIMS: ACE2, a carboxypeptidase that generates Ang-(1-7) from Ang II, is highly expressed in the lung, small intestine and colon. GPBAR1, is a G protein bile acid receptor that promotes the release of the insulinotropic factor glucagon-like peptide (GLP)-1 and attenuates intestinal inflammation. METHODS: We investigated the expression of ACE2, GLP-1 and GPBAR1 in two cohorts of Crohn's disease (CD) patients and three mouse models of colitis and Gpbar1-/- mice. Activation of GPBAR1 in these models and in vitro was achieved by BAR501, a selective GPBAR1 agonist. RESULTS: In IBD patients, ACE2 mRNA expression was regulated in a site-specific manner in response to inflammation. While expression of ileal ACE2 mRNA was reduced, the colon expression was induced. Colon expression of ACE2 mRNA in IBD correlated with expression of TNF-α and GPBAR1. A positive correlation occurred between GCG and GPBAR1 in human samples and animal models of colitis. In these models, ACE2 mRNA expression was further upregulated by GPABR1 agonism and reversed by exendin-3, a GLP-1 receptor antagonist. In in vitro studies, liraglutide, a GLP-1 analogue, increased the expression of ACE2 in colon epithelial cells/macrophages co-cultures. CONCLUSIONS: ACE2 mRNA expression in the colon of IBD patients and rodent models of colitis is regulated in a TNF-α- and GLP-1-dependent manner. We have identified a GPBAR1/GLP-1 mechanism as a positive modulator of ACE2.

Which gastric cancer patients could benefit from staging laparoscopy? A GIRCG multicenter cohort study.

BACKGROUND: This study aimed to investigate which gastric cancer patients could benefit the most from staging laparoscopy. METHODS: A retrospective cohort study was carried out, including 316 (216 cM- and 100 cM+) gastric cancer patients who had undergone staging laparoscopy between 2010 and 2020 in seven GIRCG centers. A model including easily-accessible clinical, biochemical and pathological markers was constructed to predict the risk of carcinomatosis. ROC curve and decision curve analyses were used to verify its accuracy and net benefit. RESULTS: In the cM-population staging laparoscopy could detect 67 cases who had peritoneal carcinomatosis or positive cytology, for a yield of 30.5%. In cM-patients, intestinal type tumors (0.25, 0.12-0.51; p = 0.002), cT4 tumors (2.18, 1.11-4.28; p = 0.023) and cancers of the lower third (0.31, 0.14-0.70; p = 0.004) were associated with the presence of peritoneal carcinomatosis and/or positive cytology. The ROC curve analysis of the model including the three variables showed an AUC of 0.75 (0.68-0.81, p < 0.001). The decision curve analyses showed that the model had a higher net benefit than the treating all strategy between threshold probabilities of 15 and 50%. CONCLUSIONS: Staging laparoscopy is a useful tool to address the patient with gastric cancer to the most adequate treatment. In cM-patients the assessment of the location of the tumor, the Lauren's histotype and the cT status may help in providing additional elements in indicating or not the use of staging laparoscopy.