Paired organoids from primary gastric cancer and lymphatic metastasis are useful for personalized medicine.

BACKGROUND: Organoids are approved by the US FDA as an alternative to animal experiments to guide drug development and for sensitivity screening. Stable organoids models of gastric cancer are desirable for personalized medicine and drug screening. METHODS: Tumor tissues from a primary cancer of the stomach and metastatic cancer of the lymph node were collected for 3D culture. By long-term culture for over 50 generations in vitro, we obtained stably growing organoid lines. We analyzed short tandem repeats (STRs) and karyotypes of cancer cells, and tumorigenesis of the organoids in nude mice, as well as multi-omics profiles of the organoids. A CCK8 method was used to determine the drugs sensitivity to fluorouracil (5-Fu), platinum and paclitaxel. RESULTS: Paired organoid lines from primary cancer (SPDO1P) and metastatic lymph node (SPDO1LM) were established with unique STRs and karyotypes. The organoid lines resulted in tumorigenesis in vivo and had clear genetic profiles. Compared to SPDO1P from primary cancer, upregulated genes of SPDO1LM from the metastatic lymph node were enriched in pathways of epithelial-mesenchymal transition and angiogenesis with stronger abilities of cell migration, invasion, and pro-angiogenesis. Based on drug sensitivity analysis, the SOX regimen (5-Fu plus oxaliplatin) was used for chemotherapy with an optimal clinical outcome. CONCLUSIONS: The organoid lines recapitulate the drug sensitivity of the parental tissues. The paired organoid lines present a step-change toward living biobanks for further translational usage.

Oncological outcomes of conversion therapy in gastric cancer patients with peritoneal metastasis: a large-scale retrospective cohort study.

BACKGROUND: Data on the long-term oncological outcomes of patients who undergo conversion surgery (CS) in gastric cancer (GC) patients with peritoneal metastasis (PM) are limited. METHODS: GC patients with PM who received intraperitoneal (ip) and systemic chemotherapy between April 2015 and January 2021 were enrolled. Multivariate analysis was performed to identify risk factors associated with survival. Clinicopathological and survival outcomes were compared between those with CS and those without CS (NCS). The paclitaxel (PTX) plus tegafur-gimeracil-oteracil potassium capsules (S-1) (PS) + ip PTX and oxaliplatin plus S-1 (SOX) + ip PTX groups were matched in a 1:1 ratio using propensity score matching. Oncological and survival data were collected and analyzed. RESULTS: A total of 540 patients who received ip chemotherapy via subcutaneous port and systemic chemotherapy were analyzed and 268 patients were enrolled, including 113 who underwent CS and 155 who did not. Overall survival (OS) were 27.0 months and 11.8 months in the CS and NCS groups (P < 0.0001), respectively. R0 resection was an independent prognostic factor for patients who underwent CS. The OS of patients with or without ovariectomy was 21.3 or 12.0 months (P < 0.0001). No difference of clinicopathological and survival outcomes was found between the PS + ip PTX and SOX + ip PTX groups. CONCLUSION: Conversion therapy is safe and adverse events were manageable. CS improves the survival of GC patients with PM after ip and systemic chemotherapy. R0 is an important prognostic factor. Furthermore, outcomes are comparable between the PS + ip PTX and SOX + ip PTX groups.

A short period of early life oxytocin treatment rescues social behavior dysfunction via suppression of hippocampal hyperactivity in male mice.

Early sensory experiences interact with genes to shape precise neural circuits during development. This process is vital for proper brain function in adulthood. Neurological dysfunctions caused by environmental alterations and/or genetic mutation may share the same molecular or cellular mechanisms. Here, we show that early life bilateral whisker trimming (BWT) subsequently affects social discrimination in adult male mice. Enhanced activation of the hippocampal dorsal CA3 (dCA3) in BWT mice was observed during social preference tests. Optogenetic activation of dCA3 in naive mice impaired social discrimination, whereas chemogenetic silencing of dCA3 rescued social discrimination deficit in BWT mice. Hippocampal oxytocin (OXT) is reduced after whisker trimming. Neonatal intraventricular compensation of OXT relieved dCA3 over-activation and prevented social dysfunction. Neonatal knockdown of OXT receptor in dCA3 mimics the effects of BWT, and cannot be rescued by OXT treatment. Social behavior deficits in a fragile X syndrome mouse model (Fmr1 KO mice) could also be recovered by early life OXT treatment, through negating dCA3 over-activation. Here, a possible avenue to prevent social dysfunction is uncovered.

Utility of [68Ga]FAPI-04 and [18F]FDG dual-tracer PET/CT in the initial evaluation of gastric cancer.

OBJECTIVES: We aimed to investigate the role of [68Ga]FAPI-04 and [18F]FDG dual-tracer PET/CT for the initial assessment of gastric cancer and to explore the factors associated with their uptake. METHODS: This study enrolled 62 patients with histopathologically confirmed gastric cancer. We compared the diagnostic performance of [68Ga]FAPI-04, [18F]FDG, and combined dual-tracer PET/CT. The standardized uptake value (SUV) and tumor-to-background ratio (TBR) were also measured, and the factors that influence tracer uptake were analyzed. RESULTS: [68Ga]FAPI-04 PET/CT detected more primary lesions (90.3% vs 77.4%, p = 0.008) and peritoneal metastases (91.7% vs 41.7%, p = 0.031) and demonstrated higher SUVmax and TBR values (p < 0.001) of primary lesions compared to [18F]FDG PET/CT. Dual-tracer PET/CT significantly improved the diagnostic sensitivity for the detection of distant metastases, compared with stand-alone [18F]FDG (97.1% vs 73.5%, p = 0.008) or [68Ga]FAPI-04 (97.1% vs 76.5%, p = 0.016) PET/CT. Subsequently, treatment strategies were changed in nine patients following [68Ga]FAPI-04 and [18F]FDG dual-tracer PET/CT. Nevertheless, [68Ga]FAPI-04 uptake was primarily influenced by the size and invasion depth of the tumor. Both [68Ga]FAPI-04 and [18F]FDG PET/CT showed limited sensitivity for detecting early gastric cancer (EGC) (37.5% vs 25.0%, p > 0.05). CONCLUSIONS: In this initial study, [68Ga]FAPI-04 and [18F]FDG dual-tracer PET/CT were complementary and improved sensitivity for the detection of distant metastases pre-treatment in gastric cancer and could improve treatment stratification in the future. [68Ga]FAPI-04 had limited efficacy in detecting EGC. KEY POINTS: • [68Ga]FAPI-04 and [18F]FDG dual-tracer PET/CT are complementary to each other for improving diagnostic sensitivity in the initial evaluation of distant metastases from gastric cancer. • [68Ga]FAPI-04 PET/CT showed limited sensitivity in detecting EGC. • Need for further validation in a larger multi-centre prospective study.

Exosomal hsa-let-7g-3p and hsa-miR-10395-3p derived from peritoneal lavage predict peritoneal metastasis and the efficacy of neoadjuvant intraperitoneal and systemic chemotherapy in patients with gastric cancer.

BACKGROUND: The prognosis of advanced gastric cancer (GC) invading the gastric serosa remains poor, mainly owing to high incidence of peritoneal recurrence. Patients with peritoneal metastases are often treated with neoadjuvant intraperitoneal and systemic chemotherapies (NIPS). Good responders to NIPS often undergo conversion gastrectomy. This study aims to explore biomarkers predicting the occurrence of peritoneal metastasis (PM) and evaluating the efficacy of NIPS in GC patients. METHODS: We collected six peritoneal lavage (PL) samples from two patients with PM, two without PM, and two with diminished PM after NIPS via intraperitoneal access ports. We equally isolated microRNAs from exosomes derived from PL samples for deep sequencing. Two microRNAs (hsa-let-7g-3p and hsa-miR-10395-3p) were identified, and their expression levels were examined in PL samples of 99 GC patients using qRT-PCR. Moreover, we performed in vivo and in vitro functional assays to investigate effects of these microRNAs on metastasis and chemoresistance of GC cells. RESULTS: Exosomal microRNA expression profiling of six PL samples indicated that the microRNA signature in exosomes of PLs from patients with diminished PM was similar to that from patients without PM. Expression levels of hsa-let-7g-3p and hsa-miR-10395-3p were associated with PM. In vivo and in vitro functional assays confirmed that hsa-let-7g-3p and hsa-miR-10395-3p are involved in GC metastasis and chemoresistance. CONCLUSION: PL-derived exosomes in GC contain large amounts of microRNAs related to PM. Moreover, hsa-let-7g-3p and hsa-miR-10395-3p could be used as biomarkers predicting PM and NIPS efficacy and are involved in GC metastasis and chemoresistance.

Sintilimab combined neoadjuvant intraperitoneal and systemic chemotherapy in gastric cancer with peritoneal metastasis.

Intraperitoneal chemotherapy combined with systemic chemotherapy is one of the therapeutic modalities currently used for the treatment of gastric cancer patients with peritoneal metastasis. This study was designed to evaluate the efficacy and safety of sintilimab plus S-1 combined intraperitoneal and intravenous paclitaxel. This is an open-label, single-center, phase II study including 36 gastric adenocarcinoma patients with peritoneal metastases diagnosed by laparoscopy. All enrolled patients received sintilimab, intraperitoneal and intravenous paclitaxel plus oral S-1 every 3 weeks. Conversion operation should be considered when a patient responds to the regimen and the peritoneal metastasis disappears. After gastrectomy, the protocol treatment is repeated until disease progression, unacceptable toxicity, investigator decision or patient withdrawal. The primary end point is the 1-year survival rate. Clinical Trial Registration: NCT05204173 (ClinicalTrials.gov).

Clinical characteristics and outcomes of gastrointestinal stromal tumor patients receiving surgery with or without TKI therapy: a retrospective real-world study.

PURPOSE: To retrospectively analyze the clinical characteristics of patients undergoing surgical treatment for gastrointestinal stromal tumors (GISTs) in Ruijin Hospital and explore the relevant prognosis clinical factors after surgical treatment. METHODS: We screened out 1015 patients with GISTs diagnosed and treated during January 2010 to December 2019. We performed univariate analysis by the log-rank test and multivariate analysis by COX regression. The Kaplan-Meier method was used to estimate the disease-free survival (DFS) and overall survival (OS) of the whole group. RESULTS: All 1015 patients in the whole group received radical surgery, and the proportion of patients with high, intermediate, and low risk was 31.1%, 21.7%, and 47.3%, respectively. Among the 480 low-risk patients, surgery could achieve radical therapy; only the Ki-67 index was related to DFS and OS (DFS: p = 0.032, OS: p = 0.009) among the 140 intermediate-risk patients with tumors located in the stomach, whether received Tyrosine kinase inhibitors (TKIs) therapy did not affect the prognosis of patients (DFS: p = 0.716, OS: p = 0.848). Among the 331 high-risk patients, those with non-gastric tumors (those outside the stomach, duodenum, and small intestine, HR 1.55, 95% CI 1.19-2.00, p < 0.001), tumor diameter > 10 cm (hazard ratio, HR 2.63, 95% confidence interval, CI 2.09-4.03, p < 0.001), as well as high-risk patients with mitotic rate > 10/50 HPF (HR 2.74, 95% CI 2.00-3.76, p < 0.001), the overall prognosis was obviously worse than that of other patients. For some high-risk patients, prolonged postoperative imatinib therapy could significantly improve the survival of patients (HR 0.43, 95% CI 0.15-0.66, p < 0.001). CONCLUSIONS: For the vast majority of GIST patients, surgery can be curative; but in intermediate-risk patients, the Ki-67 index and postoperative TKI treatment are closely related to prognosis. For intermediate-risk patients whose primary tumor is the stomach, the value of TKI-targeted therapy after surgery seem be not necessary in our study. However, for some high-risk patients, the prognosis of patients can be improved by appropriately prolonging the treatment time of TKI.

Benchmark for establishment of organoids from gastrointestinal epithelium and cancer based on available consumables and reagents.

Gastrointestinal cancers are a public health problem that threatens the lives of human being. A good experimental model is a powerful tool to promote the uncovering pathogenesis and establish novel treatment methods. High-quality biomedical research requires experimental models to recapitulate the physiological and pathological states of their parental tissues as much as possible. Organoids are such experimental models. Organoids refer to small organ-like cellular clusters formed by the expansion and passaging of living tissues in 3D culture medium in vitro. Organoids are highly similar to the original tissues in terms of cellular composition, cell functions, and genomic profiling. Organoids have many advantages, such as short preparation cycles, long-term storage based on cryopreservation, and reusability. In recent years, researchers carried out the establishment of organoids from gastrointestinal mucosa and cancer tissues, and accumulated valuable experiences. In order to promote effective usage and further development of organoid-related technologies in the research of gastrointestinal diseases, this study proposes a benchmark based on utilization of available experimental consumables and reagents, which are involved in the key steps such as collection and pretreatment of biospecimen, organoid construction, organoid cryopreservation and recovery, growth status evaluation, and organoid quality control. We believe that the standard for the construction and preservation of organoids derived from human gastrointestinal epithelium and cancer tissues can provide an important reference for the majority of scientific researchers.

Prognostic risk assessment model and drug sensitivity analysis of colon adenocarcinoma (COAD) based on immune-related lncRNA pairs.

PURPOSE: The aim of this study was to identify and screen long non-coding RNA (lncRNA) associated with immune genes in colon cancer, construct immune-related lncRNA pairs, establish a prognostic risk assessment model for colon adenocarcinoma (COAD), and explore prognostic factors and drug sensitivity. METHOD: Our method was based on data from The Cancer Genome Atlas (TCGA). To begin, we obtained all pertinent demographic and clinical information on 385 patients with COAD. All lncRNAs significantly related to immune genes and with differential expression were identified to construct immune lncRNA pairs. Subsequently, least absolute shrinkage and selection operator and Cox models were used to screen out prognostic-related immune lncRNAs for the establishment of a prognostic risk scoring formula. Finally, We analysed the functional differences between subgroups and screened the drugs, and establish an individual prediction nomogram model. RESULTS: Our final analysis confirmed eight lncRNA pairs to construct prognostic risk assessment model. Results showed that the high-risk and low-risk groups had significant differences (training (n = 249): p < 0.001, validation (n = 114): p = 0.022). The prognostic model was certified as an independent prognosis model. Compared with the common clinicopathological indicators, the prognostic model had better predictive efficiency (area under the curve (AUC) = 0.805). Finally, We have analysed highly differentiated cellular pathways such as mucosal immune response, identified 9 differential immune cells, 10 sensitive drugs, and establish an individual prediction nomogram model (C-index = 0.820). CONCLUSION: Our study verified that the eight lncRNA pairs mentioned can be used as biomarkers to predict the prognosis of COAD patients. Identified cells, drugs may have an positive effect on colon cancer prognosis.

The dynamic alteration of transcriptional regulation by crucial TFs during tumorigenesis of gastric cancer.

BACKGROUND: The mechanisms of Gastric cancer (GC) initiation and progression are complicated, at least partly owing to the dynamic changes of gene regulation during carcinogenesis. Thus, investigations on the changes in regulatory networks can improve the understanding of cancer development and provide novel insights into the molecular mechanisms of cancer. METHODS: Differential co-expression analysis (DCEA), differential gene regulation network (GRN) modeling and differential regulation analysis (DRA) were integrated to detect differential transcriptional regulation events between gastric normal mucosa and cancer samples based on GSE54129 dataset. Cytological experiments and IHC staining assays were used to validate the dynamic changes of CREB1 regulated targets in different stages. RESULTS: A total of 1955 differentially regulated genes (DRGs) were identified and prioritized in a quantitative way. Among the top 1% DRGs, 14 out of 19 genes have been reported to be GC relevant. The four transcription factors (TFs) among the top 1% DRGs, including CREB1, BPTF, GATA6 and CEBPA, were regarded as crucial TFs relevant to GC progression. The differentially regulated links (DRLs) around the four crucial TFs were then prioritized to generate testable hypotheses on the differential regulation mechanisms of gastric carcinogenesis. To validate the dynamic alterations of gene regulation patterns of crucial TFs during GC progression, we took CREB1 as an example to screen its differentially regulated targets by using cytological and IHC staining assays. Eventually, TCEAL2 and MBNL1 were proved to be differentially regulated by CREB1 during tumorigenesis of gastric cancer. CONCLUSIONS: By combining differential networking information and molecular cell experiments verification, testable hypotheses on the regulation mechanisms of GC around the core TFs and their top ranked DRLs were generated. Since TCEAL2 and MBNL1 have been reported to be potential therapeutic targets in SCLC and breast cancer respectively, their translation values in GC are worthy of further investigation.

Molecular evolutionary process of advanced gastric cancer during sequential chemotherapy detected by circulating tumor DNA.

BACKGROUND: Efficacy of conventional sequential chemotherapy paradigm for advanced gastric cancer (AGC) patients has largely plateaued. Dynamic molecular changes during and after sequential chemotherapy have not been fully delineated. We aimed to profile the molecular evolutionary process of AGC patients during sequential chemotherapy by next generation sequencing (NGS) of plasma circulating tumor DNA (ctDNA). METHODS: A total of 30 chemo-naïve patients who were diagnosed with unresectable advanced or metastatic stomach adenocarcinoma were enrolled. All patients received sequential chemotherapy regimens following the clinical guideline. One hundred and eight serial peripheral blood samples were collected at baseline, radiographical assessment and disease progression. Plasma ctDNA was isolated and a customized NGS panel was used to detect the genomic features of ctDNA including single nucleotide variants (SNVs) and gene-level copy number variations (CNVs). KEGG pathway enrichment analysis was performed. RESULTS: Platinum-based combination chemotherapy was administrated as first-line regimen. Objective response rate was 50% (15/30). Patients with higher baseline values of copy number instability (CNI), CNVs and variant allel frequency (VAF) were more sensitive to platinum-based first-line regimens. Tumor mutation burden (TMB), CNI and CNV burden at partial response and stable disease were significantly lower than those at baseline, where at progressive disease they recovered to baseline levels. Dynamic change of TMB (ΔTMB) was correlated with progression-free survival of first-line treatment. Fluctuating changes of SNVs and gene-level CNVs could be observed during sequential chemotherapy. Under the pressure of conventional chemotherapy, the number of novel gene-level CNVs were found to be higher than that of novel SNVs. Such novel molecular alterations could be enriched into multiple common oncologic signaling pathways, including EGFR tyrosine kinase inhibitor resistance and platinum drug resistance pathways, where their distributions were found to be highly heterogenous among patients. The impact of subsequent regimens, including paclitaxel-based and irinotecan-based regimens, on the molecular changes driven by first-line therapy was subtle. CONCLUSION: Baseline and dynamic changes of genomic features of ctDNA could be biomarkers for predicting response of platinum-based first-line chemotherapy in AGC patients. After treatment with standard chemotherapy regimens, convergent oncologic pathway enrichment was identified, which is yet characterized by inter-patient heterogenous gene-level CNVs.

ATP5B promotes the metastasis and growth of gastric cancer by activating the FAK/AKT/MMP2 pathway.

Adenosine triphosphate (ATP) in the tumor microenvironment serves a vital role during tumor progression. ATP synthase F1 ß subunit (ATP5B) is one of the most important subunits of ATP synthase and increases cellular ATP levels. ATP5B reportedly participates in carcinogenesis in several tumors. However, the regulatory mechanisms of ATP5B remain poorly understood in gastric cancer (GC). Here, we determined that high ATP5B expression in tumor tissues of GC is positively correlated with age, the tumor size, the TNM stage, lymph node metastasis, and patients' poor prognosis. The overexpression of ATP5B in GC cells elevated the cellular ATP content and promoted migration, invasion and proliferation. The levels of MMP2 expression, phosphorylated FAK, and phosphorylated AKT were increased after ATP5B overexpression in GC cells. Additionally, ATP5B overexpression increased the extracellular ATP level through the secretion of intracellular ATP and activated the FAK/AKT/MMP2 signaling pathway. ATP5B-induced downstream pathway activation was induced through the plasma membrane P2X7 receptor. Inhibitors of P2X7, FAK, AKT, and MMP2 suppressed the proliferative, migratory, and invasive capabilities of GC cells. In conclusion, our experiments indicate that ATP5B contributes to tumor progression of GC via FAK/AKT/MMP2 pathway. ATP5B, therefore, may be a biomarker of poor prognosis and a potential therapeutic target for GC.

Addition of sintilimab to nanoparticle albumin-bound paclitaxel and S-1 as adjuvant therapy in stage IIIC gastric cancer.

The prognosis of stage III gastric cancer (GC) is not satisfying and the specific chemotherapy regimens for GC of stage IIIC based on the 8th edition of the UICC/AJCC TNM staging system are still inconclusive. Peritoneal recurrence is the common and severe relapse pattern. Nanoparticle albumin-bound paclitaxel (Nab-PTX) is safer and more effective than PTX in the peritoneal metastasis. Clinical trial has demonstrated the safety and efficacy of sintilimab in GC. A combination of Nab-PTX, S-1 and sintilimab could be a promising triplet regimen as adjuvant therapy for GC. The aim of this article is to describe the design of this prospective Dragon-VII trial, conducted to evaluate the safety and efficacy of the combination of Nab-PTX, S-1 and sintilimab. Clinical trial registration: NCT04781413.

Lay abstract The prognosis of stage IIIC gastric cancer is poor and the treatment for it is not satisfying. This is a clinical trial that aims to explore a more effective therapy in gastric cancer patients of stage IIIC. Patients with stage IIIC gastric cancer must meet all of the inclusion criteria and none of the exclusion criteria to be eligible for this trial. The eligible patients will be given eight cycles of combinatory therapy of albumin-bound paclitaxel, a chemotherapy (day 1 and day 8), and S-1, another chemotherapy (days 1 to 14), plus sintilimab, a type of immunotherapy called an immune checkpoint inhibitor (day 1) every 3 weeks and then sintilimab maintenance for up to 12 months.

A phase III trial of neoadjuvant intraperitoneal and systemic chemotherapy for gastric cancer with peritoneal metastasis.

Although recent advances in systemic chemotherapy have improved the clinical outcomes of gastric cancer patients with peritoneal metastasis, the peritoneum still represents a common site of treatment failure and disease recurrence. Neoadjuvant intraperitoneal-systemic chemotherapy has been acknowledged as a more aggressive treatment for gastric cancer patients with peritoneal metastasis. In this multicenter phase III randomized controlled trial, 238 patients will be randomly separated into two groups in a 2:1 ratio after laparoscopic exploration. The experimental arm will receive the proposed neoadjuvant intraperitoneal-systemic chemotherapy regimen, whereas the control group will receive a Paclitaxel + S-1 (PS) chemotherapy regimen. The endpoints for the study are overall survival, response rate, gastrectomy radicality rate, progression-free survival and adverse events.

Recent advances in technology have improved the outcomes of stomach cancer patients. However, there are still many patients who die of cancer that has spread from another part of the body. Neoadjuvant intraperitoneal­systemic chemotherapy has been acknowledged as a more aggressive treatment for stomach cancer patients with peritoneal metastasis (cancer that has spread to the very thin layer of tissue on the inside of the abdomen that covers the stomach and other organs). In this study, 238 patients will be randomly separated into two groups in a 2:1 ratio after evaluation. The experimental group will receive the proposed neoadjuvant intraperitoneal­systemic chemotherapy regimen, whereas the control group will receive a Paclitaxel + S-1 (PS) chemotherapy regimen. The endpoints for the study are how long patients live, number of patients who respond to treatment, number of patients who undergo surgery, how long patients live without their disease getting worse and problems caused by treatment. Trial registration number: ChiCTR-IIR-16009802.

A phase II study of perioperative treatment in gastric cancer with No.16a2/b1 lymph node metastasis: DRAGON-06 trial.

Although gastric cancer with para-aortic lymph node (PAN) metastasis is commonly regarded as unresectable, surgeons have explored the optimal treatment for patients with PAN metastases limited to No.16a2/b1 in the past few decades. Preoperative systemic therapy combined with D2 gastrectomy plus PAN dissection may improve the prognosis of these patients. In this multicenter phase II trial, 29 gastric cancer patients with PAN metastasis limited to No.16a2/b1 will receive preoperative treatment with nab-paclitaxel, oxaliplatin, S-1 (nab-POS: nab-paclitaxel, oxaliplatin, S-1) and sintilimab followed by D2 gastrectomy plus PAN dissection; and postoperative treatment with oral S-1, intravenous sintilimab and intraperitoneal paclitaxel. The end points for the study are 3-year overall survival, 3-year disease-free survival, pathological response rate, incidence of postoperative complications and adverse events.

Stomach cancer with metastases in the para-aortic lymph nodes is usually considered inoperable. Chemotherapy combined with resection of the stomach and more extensive lymph node dissection may prolong the life of these patients. In this multicenter study, 29 stomach cancer patients with para-aortic lymph node metastases will receive preoperative treatment with nab-paclitaxel, oxaliplatin, S-1 and sintilimab, followed by resection of the stomach combined with para-aortic lymph node dissection and use of continued oral, intravenous and intraperitoneal chemotherapy. The study's end points are 3-year overall survival, 3-year disease-free survival, pathological response rate, incidence of postoperative complications and adverse events. Clinical Trial Registration: ChiCTR2200061125 (ChiCTR.org.cn).

Oxaliplatin plus S-1 with intraperitoneal paclitaxel for the treatment of Chinese advanced gastric cancer with peritoneal metastases.

BACKGROUND: In this study, we tried to access the efficacy and safety of oxaliplatin plus S-1 with intraperitoneal paclitaxel (PTX) for the treatment of Chinese advanced gastric cancer with peritoneal metastases. PATIENTS AND METHODS: Thirty patients diagnosed with advanced gastric cancer underwent laparoscopic exploration and were enrolled when macroscopic disseminated metastases (P1) were confirmed. PTX was diluted in 1 l of normal saline and IP administered through peritoneal port at an initial dose of 40 mg/m2 over 1 h on day1,8, respectively. Oxaliplatin was administered intravenously at an initial dose of 100 mg/m2 on day1, and S-1 was administered orally at an initial dose of 80 mg/m2 for 14 days followed by 7 days rest, repeated by every 3 weeks. RESULTS: Of all these 30 patients, the median number of cycles was 6 (range 2-16) due to the limitation of hematotoxicity and peripheral neuropathy by oxaliplatin. There were 11 (36.7%) patients received conversion surgery. The median progression free survival (PFS) was 6.6 months (95% CI = 4.7-8.5 months) and the median overall survival (OS) was 15.1 months (95% CI = 12.4-17.8 months). The grade 3-4 hematological toxicities were leucopenia (23.3%), neutropenia (23.3%), anemia (16.7%), and thrombocytopenia (20%), respectively. The grade 3-4 non-hematological toxicities were tolerated, most of which were peripheral sensory neuropathy (40%) due to oxaliplatin, diarrhea (20%), nausea and vomiting (26.7%). CONCLUSIONS: SOX+ip PTX regimen was effective in advanced gastric cancer with peritoneal metastasis. Survival time was significantly prolonged by conversion surgery. Grade 3-4 toxicities were uncommon. Large scale clinical trial is necessary to get more evidence to identify its efficacy. TRAIL REGISTRATION: ChiCTR, ChiCTR-IIR-16009802 . Registered 9 November 2016.

Which Staging System Is More Suitable for Gastric Neuroendocrine Cancer and Mixed Adenoneuroendocrine Carcinomas? A Multicenter Cohort Study.

PURPOSE: To evaluate whether the European Neuroendocrine Tumor Society (ENETS) system or the 8th American Joint Committee on Cancer (AJCC) staging manual are suitable for gastric neuroendocrine carcinomas and/or mixed adenoneuroendocrine carcinomas (G-NECs/MANECs). METHODS: Patients in a multicentric series with G-NEC/MANEC who underwent curative-intent surgical resection for a primary tumor were included. An optimal staging system was proposed base on analysis of the T and N status and validated by the SEER database. RESULTS: Compared with the ENETS system, the survival curves of the T category and N category in the 8th AJCC system were better separated and distributed in a more balanced way, but the survival curves of T2 vs. T3, N0 vs. N1, and N3a vs. N3b overlapped. For the T category, the 8th AJCC T category was modified by combining T2 and T3, which was consistent with the T category in the 6th AJCC manual for GC. For the N category, the optimal cut-off values of metastatic lymph nodes using X-tile were also similar to those of the N category in the 6th AJCC system. The Kaplan-Meier plots of the 6th AJCC system showed statistically significant differences between individual substages. Compared with the other 2 classifications, the 6th AJCC system also showed superior prognostic stratification. Similar results were obtained in both multicentric and SEER validation sets. CONCLUSIONS: Compared to the 8th AJCC and ENETS systems, the 6th AJCC staging system for GC is more suitable for G-NEC/MANEC and can be adopted in clinical practice.

Impact of microsatellite status on negative lymph node count and prognostic relevance after curative gastrectomy.

BACKGROUND AND OBJECTIVES: The impact of microsatellite instability-high (MSI-H) phenotype on lymph node yield after lymphadenectomy has never been discussed in gastric cancer (GC). In this study, we aimed to assess the association of microsatellite status with negative lymph node count (NLNC) as well as its prognostic value. METHODS: We retrospectively analyzed 1491 GC patients and divided them into two groups: MSI-HGC (n = 141 [9.5%]) and microsatellite stability (MSSGC ) (n = 1350 [90.5%]). The NLNC and survival data were compared between the two groups. The log odds of positive lymph nodes (LNs) to negative LNs and the target lymph node examined threshold (TLNT) were calculated in both groups. RESULTS: A statistically significant difference was found in median NLNC (26 vs. 23, p < .001) between MSI-HGC and MSSGC patients. MSI status was an independent factor for NLNC (p < .001). NLNC showed positive prognostic value for cases with metastatic lymph node (LN+ ) in both MSI-HGC and MSSGC groups. The TLNT(90%) for MSI-HGC and MSSGC were 33 and 26, respectively. CONCLUSIONS: MSI-HGC was associated with higher NLNC in GC patients and this was independent of the presence of LN+ . However, more LNs are needed during pathological examination to capture LN+ cases in MSI-HGC.

Multi-institutional development and validation of a nomogram to predict recurrence after curative resection of gastric neuroendocrine/mixed adenoneuroendocrine carcinoma.

OBJECTIVE: To establish a novel nomogram to predict individual 1, 3, and 5 years disease-free survival (DFS) of patients with gastric neuroendocrine carcinoma/mixed adenoneuroendocrine carcinoma [(MA)NEC]. BACKGROUND: Among patients undergoing radical resection of gastric (MA)NEC, there is still a high tendency for relapse. METHODS: A retrospective analysis of 777 patients with gastric (MA)NEC at 23 centers in China from 2004 to 2015 was performed. Based on the established nomogram, which included age, ASA, pT, pN and Ki67, the overall patients were divided into low-risk group (LRG) and high-risk group (HRG). RESULTS: The median follow-up time was 40 months (1-169 months). The C-index, AUC and time-ROC of the nomogram were significantly higher than that of the 8th edition AJCC and ENETS TNM staging systems. The 3-year DFS of patients in HRG generated by the nomogram was significantly lower than that in LRG (all patients: 35% vs 66.9%, p < 0.001), and there were still significant differences in stratified analysis of the TNM staging systems. The local recurrence rate (10.5% vs 2.6%) and distant recurrence rate (45.1% vs 22.6%) in HRG were significantly higher than those in LRG, especially in anastomotic recurrence (6.3% vs 2%), liver recurrence (20.7% vs 13.4%) and peritoneal metastasis (12.7% vs 2.6%). CONCLUSIONS: Compared with AJCC and ENETS TNM staging systems, the established novel validated nomogram had a significantly better prediction ability for DFS and recurrence patterns in patients with gastric (MA)NEC. It can also compensate for the shortcomings of existing AJCC and ENETS TNM staging in predicting individual recurrence risk.

A randomized controlled trial to evaluate omentum-preserving gastrectomy for patients with T1-T3 gastric cancer.

Although complete omentectomy is traditionally performed in patients with gastric cancer as part of radical gastrectomy to ensure the elimination of micrometastases, the prognostic value of omentectomy during gastrectomy remains unclear. Retrospective studies have shown that the incidence of metastases in the greater omentum is very low in T1-T3 gastric cancer. Thus radical gastrectomy with D2 lymphadenectomy and preservation of the greater omentum may be a proper curative treatment for gastric cancer patients with T1-T3 tumors. The aim of this article is to describe the design and rationale for this prospective, randomized controlled DRAGON-05 trial, conducted to evaluate the prognostic value of omentum-preserving gastrectomy for patients with T1-T3 gastric cancer. Clinical trial registration: ChiCTR2000040045 (ClinicalTrials.gov).