Efficacy and safety of intraperitoneal chemotherapy for pancreatic cancer.

Pancreatic cancer is a highly aggressive cancer with unfavorable prognosis despite the therapeutic interventions. Intraperitoneal chemotherapy has recently shown potential outcomes in the presence of peritoneal metastases. However, a consensus is still lacking on different methods for intraperitoneal chemotherapy in pancreatic cancer. A variety of drugs and doses via three types of intraperitoneal chemotherapy have been studied. The prognosis and treatment strategies for pancreatic ductal adenocarcinoma (PDAC) will be significantly influenced by peritoneal dissemination and resectability of the macroscopic disease. Normothermic intraperitoneal chemotherapy (NIPEC) has been used for the treatment of peritoneal metastases of pancreatic carcinomas. Intraperitoneal chemotherapy is often combined with systemic therapies or surgical procedures which may lead to favorable combination therapies such as cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a relatively new approach that provides a homogenous and deep penetration of the chemotherapy into the peritoneum by producing aerosols. The present study aims to review the literature for recent evidence on intraperitoneal chemotherapy in pancreatic cancer.

Hyperthermic intraoperative peritoneal chemotherapy and cytoreductive surgery for people with peritoneal metastases: a systematic review and cost-effectiveness analysis.

Background: We compared the relative benefits, harms and cost-effectiveness of hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery ± systemic chemotherapy versus cytoreductive surgery ± systemic chemotherapy or systemic chemotherapy alone in people with peritoneal metastases from colorectal, gastric or ovarian cancers by a systematic review, meta-analysis and model-based cost-utility analysis. Methods: We searched MEDLINE, EMBASE, Cochrane Library and the Science Citation Index, ClinicalTrials.gov and WHO ICTRP trial registers until 14 April 2022. We included only randomised controlled trials addressing the research objectives. We used the Cochrane risk of bias tool version 2 to assess the risk of bias in randomised controlled trials. We used the random-effects model for data synthesis when applicable. For the cost-effectiveness analysis, we performed a model-based cost-utility analysis using methods recommended by The National Institute for Health and Care Excellence. Results: The systematic review included a total of eight randomised controlled trials (seven randomised controlled trials, 955 participants included in the quantitative analysis). All comparisons other than those for stage III or greater epithelial ovarian cancer contained only one trial, indicating the paucity of randomised controlled trials that provided data. For colorectal cancer, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably results in little to no difference in all-cause mortality (60.6% vs. 60.6%; hazard ratio 1.00, 95% confidence interval 0.63 to 1.58) and may increase the serious adverse event proportions compared to cytoreductive surgery ± systemic chemotherapy (25.6% vs. 15.2%; risk ratio 1.69, 95% confidence interval 1.03 to 2.77). Hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably decreases all-cause mortality compared to fluorouracil-based systemic chemotherapy alone (40.8% vs. 60.8%; hazard ratio 0.55, 95% confidence interval 0.32 to 0.95). For gastric cancer, there is high uncertainty about the effects of hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy versus cytoreductive surgery + systemic chemotherapy or systemic chemotherapy alone on all-cause mortality. For stage III or greater epithelial ovarian cancer undergoing interval cytoreductive surgery, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably decreases all-cause mortality compared to cytoreductive surgery + systemic chemotherapy (46.3% vs. 57.4%; hazard ratio 0.73, 95% confidence interval 0.57 to 0.93). Hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy may not be cost-effective versus cytoreductive surgery + systemic chemotherapy for colorectal cancer but may be cost-effective for the remaining comparisons. Limitations: We were unable to obtain individual participant data as planned. The limited number of randomised controlled trials for each comparison and the paucity of data on health-related quality of life mean that the recommendations may change as new evidence (from trials with a low risk of bias) emerges. Conclusions: In people with peritoneal metastases from colorectal cancer with limited peritoneal metastases and who are likely to withstand major surgery, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy should not be used in routine clinical practice (strong recommendation). There is considerable uncertainty as to whether hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy or cytoreductive surgery + systemic chemotherapy should be offered to patients with gastric cancer and peritoneal metastases (no recommendation). Hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy should be offered routinely to women with stage III or greater epithelial ovarian cancer and metastases confined to the abdomen requiring and likely to withstand interval cytoreductive surgery after chemotherapy (strong recommendation). Future work: More randomised controlled trials are necessary. Study registration: This study is registered as PROSPERO CRD42019130504. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/135/02) and is published in full in Health Technology Assessment; Vol. 28, No. 51. See the NIHR Funding and Awards website for further award information.

Cancers of the bowel, ovary or stomach can spread to the lining of the abdomen ('peritoneal metastases'). Chemotherapy (the use of drugs that aim to kill cancer cells) given by injection or tablets ('systemic chemotherapy') is one of the main treatment options. There is uncertainty about whether adding cytoreductive surgery (cytoreductive surgery; an operation to remove the cancer) and 'hyperthermic intraoperative peritoneal chemotherapy' (warm chemotherapy delivered into the lining of the abdomen during cytoreductive surgery) are beneficial. We reviewed all the information from medical literature published until 14 April 2022, to answer the above uncertainty. We found the following from eight trials, including about 1000 participants. In people with peritoneal metastases from bowel cancer, hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably does not provide any benefits and increases harm compared to cytoreductive surgery + systemic chemotherapy, while cytoreductive surgery + systemic chemotherapy appears to increase survival compared to systemic chemotherapy alone. There is uncertainty about the best treatment for people with peritoneal metastases from stomach cancer. In women with peritoneal metastases from ovarian cancer who require systemic chemotherapy before cytoreductive surgery to shrink the cancer to allow surgery ('advanced ovarian cancer'), hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy probably increases survival compared to cytoreductive surgery + systemic chemotherapy. In people who can withstand a major operation and in whom cancer can be removed, cytoreductive surgery + systemic chemotherapy should be offered to people with peritoneal metastases from bowel cancer, while hyperthermic intraoperative peritoneal chemotherapy + cytoreductive surgery + systemic chemotherapy should be offered to women with peritoneal metastases from 'advanced ovarian cancer'. Uncertainty in treatment continues for gastric cancer. This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/135/02) and is published in full in Health Technology Assessment; Vol. 28, No. 51. See the NIHR Funding and Awards website for further award information.

Exosomes: Key Factors in Ovarian Cancer Peritoneal Metastasis and Drug Resistance.

Ovarian cancer remains a leading cause of death among gynecological cancers, largely due to its propensity for peritoneal metastasis and the development of drug resistance. This review concentrates on the molecular underpinnings of these two critical challenges. We delve into the role of exosomes, the nano-sized vesicles integral to cellular communication, in orchestrating the complex interactions within the tumor microenvironment that facilitate metastatic spread and thwart therapeutic efforts. Specifically, we explore how exosomes drive peritoneal metastasis by promoting epithelial-mesenchymal transition in peritoneal mesothelial cells, altering the extracellular matrix, and supporting angiogenesis, which collectively enable the dissemination of cancer cells across the peritoneal cavity. Furthermore, we dissect the mechanisms by which exosomes contribute to the emergence of drug resistance, including the sequestration and expulsion of chemotherapeutic agents, the horizontal transfer of drug resistance genes, and the modulation of critical DNA repair and apoptotic pathways. By shedding light on these exosome-mediated processes, we underscore the potential of exosomal pathways as novel therapeutic targets, offering hope for more effective interventions against ovarian cancer's relentless progression.

Phase I PIANO trial-PIPAC-oxaliplatin and systemic nivolumab combination for gastric cancer peritoneal metastases: clinical and translational outcomes.

INTRODUCTION: Pressurized intraperitoneal aerosol chemotherapy-oxaliplatin (PIPAC-OX) induces direct DNA damage and immunogenic cell death in patients with gastric cancer peritoneal metastases (GCPM). Combining PIPAC-OX with immune checkpoint inhibition remains untested. We conducted a phase I first-in-human trial evaluating the safety and efficacy of PIPAC-OX combined with systemic nivolumab (NCT03172416). METHODS: Patients with GCPM who experienced disease progression on at least first-line systemic therapy were recruited across three centers in Singapore and Belgium. Patients received PIPAC-OX at 90 mg/m2 every 6 weeks and i.v. nivolumab 240 mg every 2 weeks. Translational studies were carried out on GCPM samples acquired during PIPAC-OX procedures. RESULTS: In total, 18 patients with GCPM were prospectively recruited. The PIPAC-OX and nivolumab combination was well tolerated with manageable treatment-related adverse events, although one patient suffered from grade 4 vomiting. At second and third PIPAC-OX, respectively, the median decrease in peritoneal cancer index (PCI) was -5 (interquartile range: -12 to +1) and -7 (interquartile range: -6 to -20) and peritoneal regression grade 1 or 2 was observed in 66.7% (6/9) and 100% (3/3). Translational analyses of 43 GCPM samples revealed enrichment of immune/stromal infiltration and inflammatory signatures in peritoneal tumors after PIPAC-OX and nivolumab. M2 macrophages were reduced in treated peritoneal tumor samples while memory CD4+, CD8+ central memory and naive CD8+ T-cells were increased. CONCLUSIONS: The first-in-human trial combining PIPAC-OX and nivolumab demonstrated safety and tolerability, coupled with enhanced T-cell infiltration within peritoneal tumors. This trial sets the stage for future combinations of systemic immunotherapy with locoregional intraperitoneal treatments.

Effects of HyaRegen gel on tumour proliferation of colorectal peritoneal metastases.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a valuable therapeutic alternative for patients with peritoneal metastases. PIPAC uses a hyaluronic acid-based gel to reduce surgically induced adhesions. The aim of this study was to evaluate the effects of the hyaluronic acid-based gel on tumor dissemination. First, we explored whether the survival of CT26 luciferase-expressing murine colonic tumor cells was correlated with the dose of HyaRegen® Gel, and we determined the half-maximal inhibitory concentration (the IC50) of the gel. Next, we performed an in vitro study of cell survival rates after gel application on day 0 (D0) and day 1 (D1). Finally, we intraperitoneally administered the gel to mice with immunocompetent BALB/c colonic peritoneal metastases (on D0, D5, D10, D14, and D18). Tumor growth was regularly monitored using a bioluminescence assay (on D11, D17, and D21). After all mice had been sacrificed on D21, the body weights and the volumes of intraperitoneal ascites were measured; the Peritoneal Carcinosis Index (PCI) and Ki-antigen 67 scores were calculated. The IC50 value was 70 µL of gel in a total volume of 100 µL. The cell survival rates on D4 were identical in the control group and the two groups that had been treated with gel on D0 and D1. The bioluminescence levels over time were similar in the gel and control groups. The PCI scores were 35.5 ± 2.89 for the control group and 36 ± 2.45 for the gel group (p = 0.8005). The mean Ki-67 index percentages were 37.28 ±1 1.75 for the control group and 34.03 ± 8.62 for the gel group (p = 0.1971). This in vitro and in vivo study using a mouse model of immunocompetent metastatic peritoneal cancer did not reveal any pro- or anti-tumoral effect of HyaRegen® Gel. These findings indicate that the gel can be used to treat PIPACs with minimal apprehension.

Niraparib in Japanese patients with heavily pretreated, homologous recombination-deficient ovarian cancer: final results of a multicenter phase 2 study.

OBJECTIVE: To evaluate the long-term efficacy and safety of niraparib in Japanese women with heavily pretreated ovarian cancer. METHODS: This was the follow-up analysis of a phase 2, multicenter, open-label, single-arm study in Japanese women with homologous recombination-deficient, platinum-sensitive, relapsed, high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer who had completed 3-4 lines of chemotherapy and were poly(ADP-ribose) polymerase inhibitor naïve. Participants received niraparib (starting dose, 300 mg) once daily in continuous 28-day cycles until objective disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoint was confirmed objective response rate (ORR), as assessed using Response Evaluation Criteria in Solid Tumors version 1.1. Safety evaluations included treatment-emergent adverse events (TEAEs). RESULTS: 20 patients were enrolled in the study and included in both efficacy and safety analyses. Median total study duration was 759.5 days. Median dose intensity was 201.3 mg/day. Confirmed ORR was 60.0% (90% confidence interval [CI]=39.4-78.3); 2 patients had complete response and 10 patients had partial response. Median duration of response was 9.9 months (95% CI=3.9-26.9) and the disease control rate was 90.0% (95% CI=68.3-98.8). The most common TEAEs were anemia (n=15), nausea (n=12), and decreased platelet count (n=11). TEAEs leading to study drug dose reduction, interruption, or discontinuation were reported in 16 (80.0%), 15 (75.0%), and 2 patients (10.0%), respectively. CONCLUSION: The long-term efficacy and safety profile of niraparib was consistent with previous findings in the equivalent population in non-Japanese patients. No new safety signals were identified. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03759600.

[Long-Term Survival of a Case with Peritoneal Dissemination from Appendiceal Goblet Cell Carcinoid Treated with Systemic Chemotherapy].

A 64-year-old man complained of lower abdominal pain and vomiting. The CT scan showed adhesional ileus; therefore, small bowel resection procedure was performed. Histological findings showed signet-ring cell carcinoma and poorly differentiated adenocarcinoma. We performed ileocecal resection as an additional surgery. The operative findings revealed peritoneal nodules. The histological findings suggested goblet cell carcinoid with peritoneal dissemination. mFOLFOX+bevacizumab was administered, and no progression was observed for 30 months after the surgery. Appendiceal goblet cell carcinoid is rare and its prognosis is poor. Here, we report a case of appendiceal GCC that achieved a relatively long-term survival despite peritoneal dissemination.

Is Hyperthermic Intraperitoneal Chemotherapy Appropriate for Colon Cancer?

Colorectal cancer (CRC) with peritoneal metastases is a complex disease and its management presents significant clinical challenges. In well-selected patients at experienced centers, CRS/hyperthermic intraperitoneal chemotherapy (HIPEC) can be performed with acceptable morbidity and is associated with prolonged survival. Based on the results of recent randomized controlled trials, HIPEC using oxaliplatin after CRS with shortened perfusion periods (30 minutes) is no longer recommended. There is a movement toward utilizing mitomycin C as a first-line intraperitoneal agent with extended perfusion times (90-120 minutes); however, there is currently little prospective evidence to support its widespread use.

Assessment of chemical stability of monoclonal antibody and antibody drug conjugate administered by pressurized intraperitoneal aerosol chemotherapy.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a new therapeutic approach for patients with peritoneal cancer. So far, most published studies investigated the administration of established cytostatic agents through PIPAC. This study aimed to evaluate the effect of PIPAC on two breakthrough anti-cancer agents, specifically anti-PD1 pembrolizumab, and anti-HER2 antibody-drug conjugate (ADC) - trastuzumab-deruxtecan. We conducted systematic analyses on samples of pembrolizumab and trastuzumab-deruxtecan at clinically relevant concentrations before and after PIPAC administration using an experimental setup of a hermetic container system, mimicking the abdominal cavity and using identical features as in clinical use. We utilized a range of chromatographic and spectroscopic techniques to explore potential alterations in the primary, secondary, and tertiary structures of the drugs, focusing on post-translational modifications resulting from the aerosolization. Our findings indicate that PIPAC did not compromise the integrity of tested biopharmaceuticals. The size variants of both drugs, assessed by size exclusion chromatography (SEC), remained unchanged. Reversed-phase liquid chromatography (RPLC) and hydrophobic interaction chromatography (HIC) revealed no significant differences in hydrophobicity variants, the average drug-to-antibody ratio (DAR), or DAR distribution before and after PIPAC treatment. Circular dichroism (CD) spectroscopy confirmed that the secondary and tertiary structures were preserved. While pembrolizumab showed no change in charge variants post-PIPAC, trastuzumab-deruxtecan exhibited a non-negligible change in the quantity of charge variants on the monoclonal antibody itself, while the payload remained unchanged. This shift could possibly be related to the metallic composition of the CapnoPen® device (made of nickel and chromium) used in PIPAC and for these experiments. Together, our results suggest that PIPAC does not alter the structure of pembrolizumab and trastuzumab-deruxtecan, paving the way for future clinical trials.

Phase I/II Clinical Study of PRaG Regimen Combined With Intraperitoneal Infusion of PD-1 Inhibitor for Advanced Refractory Solid Tumors With Cancerous Ascites (PRaG4.0P Study).

Objective: The prognosis of malignant tumors with peritoneal metastases and cancerous ascites has generally been poor, with limited treatment options. The PRaG regimen, which comprised of hypofractionated radiotherapy, programmed cell death-1 (PD-1) inhibitor, and granulocyte-macrophage colony-stimulating factor (GM-CSF), showed a survival advantage in patients with advanced solid tumors who failed at least the first line of standard systemic treatment. Intraperitoneal infusion of PD-1 inhibitors may be a novel therapeutic strategy for managing malignant ascites. Integrating the PRaG regimen with intraperitoneal perfusion of a PD-1 inhibitor might control malignant ascites and provide further survival benefits in these patients. This proposed study aims to investigate the safety and efficacy of intraperitoneal infusion of serplulimab in combination with the PRaG regimen in patients with simultaneous advanced solid tumors and cancerous ascites who fail at least the first-line treatment. Methods: This proposed study is a prospective, single-arm, open-label, multicenter clinical trial. All eligible patients will receive 2 cycles of intensive treatment, a combination of PRaG regimen with an intraperitoneal infusion of PD-1 inhibitor. The patients who are beneficially treated with intensive treatment will receive consolidation treatment every 2 weeks until ascites disappear, disease progression occurs, intolerable toxicity occurs, or for up to 1 year. Phase I of this study will be conducted using a modified 3 + 3 design. The dose of intraperitoneal infusion of PD-1 inhibitor for phase II will be determined according to dose-limiting toxicity evaluation in the phase I study. Conclusion: This prospective, open-label, multicenter study will potentially lead to intraperitoneal perfusion of a PD-1 inhibitor being a new strategy for malignant ascites patients and provide a meaningful efficacy and safety of the combination of PRaG regimen with an intraperitoneal infusion of PD-1 inhibitor for these patients.

Cytoreductive surgery without intra-peritoneal chemotherapy for metachronous colorectal peritoneal metastases.

BACKGROUND: Cytoreductive surgery and chemotherapy reportedly improve the prognosis of patients with metachronous peritoneal metastases. However, the types of peritoneal metastases indicated for cytoreductive surgery remains unclear. Therefore, we aimed to clarify the category of cases for which cytoreductive surgery would be effective and report the prognosis associated with cytoreductive surgery for metachronous peritoneal metastases. METHODS: This study included 52 consecutive patients who underwent cytoreductive surgery for metachronous peritoneal metastases caused by colorectal cancer between January 2005 and December 2018 and fulfilled the selection criteria. The median follow-up period was 54.9 months. Relapse-free survival was calculated as the time from cytoreductive surgery of metachronous peritoneal metastases to recurrence. Overall survival was defined as the time from cytoreductive surgery of metachronous peritoneal metastases to death or the end of the follow-up period. RESULTS: The 5-year relapse-free survival rate was 30.0% and the 5-year overall survival rate was 72.3%. None of the patients underwent hyperthermic intraperitoneal chemotherapy. The analysis indicated no potential risk factors for 5-year relapse-free survival. However, for 5-year overall survival, the multivariate analysis revealed that time to diagnosis of metachronous peritoneal metastases of < 2 years after primary surgery (hazard ratio = 4.1, 95% confidence interval = 2.0-8.6, p = 0.0002) and number of metachronous peritoneal metastases ≥ 3 (hazard ratio = 9.8, 95% confidence interval = 2.3-42.3, p = 0.002) as independent factors associated with a poor prognosis. CONCLUSIONS: Long intervals of more than 2 years after primary surgery and 2 or less metachronous peritoneal metastases were good selection criteria for cytoreductive surgery for metachronous peritoneal metastases from colorectal cancer.

Precision Oncology and Systemic Targeted Therapy in Pseudomyxoma Peritonei.

PURPOSE: Pseudomyxoma peritonei (PMP) is a rare and poorly understood malignant condition characterized by the accumulation of intra-abdominal mucin produced from peritoneal metastases. Currently, cytoreductive surgery remains the mainstay of treatment but disease recurrence and death after relapse frequently occur in patients with PMP. New therapeutic strategies are therefore urgently needed for these patients. EXPERIMENTAL DESIGN: A total of 120 PMP samples from 50 patients were processed to generate a collection of 50 patient-derived organoid (PDO) and xenograft (PDX) models. Whole exome sequencing, immunohistochemistry analyses, and in vitro and in vivo drug efficacy studies were performed. RESULTS: In this study, we have generated a collection of PMP preclinical models and identified druggable targets, including BRAFV600E, KRASG12C, and KRASG12D, that could also be detected in intra-abdominal mucin biopsies of patients with PMP using droplet digital PCR. Preclinical models preserved the histopathological markers from the original patient sample. The BRAFV600E inhibitor encorafenib reduced cell viability of BRAFV600E PMP-PDO models. Proof-of-concept in vivo experiments showed that a systemic treatment with encorafenib significantly reduced tumor growth and prolonged survival in subcutaneous and orthotopic BRAFV600E-PMP-PDX mouse models. CONCLUSIONS: Our study demonstrates for the first time that systemic targeted therapies can effectively control PMP tumors. BRAF signaling pathway inhibition represents a new therapeutic opportunity for patients with BRAFV600E PMP who have a poor prognosis. Importantly, our present data and collection of preclinical models pave the way for evaluating the efficacy of other systemic targeted therapies toward extending the promise of precision oncology to patients with PMP.

Examining the impact of age on chemotherapy completion in epithelial ovarian, fallopian tube and primary peritoneal cancer: a retrospective cohort study in Thailand.

OBJECTIVE: To explore the difference in chemotherapy completion and reasons for discontinuation between older (≥70 years) and younger (<70 years) patients. DESIGN: Retrospective cohort study. SETTING: Single tertiary centre in Thailand. PARTICIPANTS: The patients who received chemotherapy from 1 January 2009 to 30 June 2021 were included and followed up until 30 June 2022. Of the 757 patients with epithelial ovarian, fallopian tube and primary peritoneal cancer (EOC), 108 were in the older group and 649 were in the younger group. PRIMARY AND SECONDARY OUTCOME MEASURES: The difference in chemotherapy completion, the association between younger and older patients and early discontinuation of chemotherapy. RESULTS: The proportion of chemotherapy completion was significantly lower in older versus younger patients (84.3% versus 92.6%, p=0.007). Excluding discontinuation due to disease progression, the chemotherapy completion was comparable (93.5 versus 95.7%, p=0.456). Dose reduction and grade 3-4 hematotoxicity occurred more often in the older group. The univariable logistic regression model showed that older age (≥70 years) was significantly associated with early chemotherapy discontinuation (OR 2.39; 95% CI 1.29-4.24). However, after adjusting for potential confounders, age was not significantly associated with early discontinuation (OR 1.20; 95% CI 0.54-2.66). Multiple comorbidities and types of surgery were identified as independent risk factors for chemotherapy discontinuation. CONCLUSION: The completion of chemotherapy was observed in a majority of older adults with EOC. Age is not the only determinant of chemotherapy completion. Comorbidity and disease status are crucial for determining chemotherapy discontinuation.

Intraperitoneal drug delivery systems for peritoneal carcinomatosis: Bridging the gap between research and clinical implementation.

Several abdominal-located cancers develop metastasis within the peritoneum, what is called peritoneal carcinomatosis (PC), constituting a clinical challenge in their therapeutical management, often leading to poor prognoses. Current multidisciplinary strategies, including cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and pressurized intraperitoneal aerosol chemotherapy (PIPAC), demonstrate efficacy but have limitations. In response, alternative strategies are explored in the drug delivery field for intraperitoneal chemotherapy. Controlled drug delivery offers a promising avenue, maintaining localized drug concentrations for optimal PC management. Drug delivery systems (DDS), including hydrogels, implants, nanoparticles, and hybrid systems, show potential for sustained and region-specific drug release. The present review aims to offer an overview of the advances and current designs of DDS for PC chemotherapy administration, focusing on their composition, main characteristics, and principal experimental outcomes, highlighting the importance of biomaterial rationale design and in vitro/vivo models for their testing. Moreover, since clinical data for human subjects are scarce, we offer a critical discussion of the gap between bench and bedside in DDS translation, emphasizing the need for further research.

SMYD5 methylation of rpL40 links ribosomal output to gastric cancer.

Dysregulated transcription due to disruption in histone lysine methylation dynamics is an established contributor to tumorigenesis1,2. However, whether analogous pathologic epigenetic mechanisms act directly on the ribosome to advance oncogenesis is unclear. Here we find that trimethylation of the core ribosomal protein L40 (rpL40) at lysine 22 (rpL40K22me3) by the lysine methyltransferase SMYD5 regulates mRNA translation output to promote malignant progression of gastric adenocarcinoma (GAC) with lethal peritoneal ascites. A biochemical-proteomics strategy identifies the monoubiquitin fusion protein partner rpL40 (ref. 3) as the principal physiological substrate of SMYD5 across diverse samples. Inhibiting the SMYD5-rpL40K22me3 axis in GAC cell lines reprogrammes protein synthesis to attenuate oncogenic gene expression signatures. SMYD5 and rpL40K22me3 are upregulated in samples from patients with GAC and negatively correlate with clinical outcomes. SMYD5 ablation in vivo in familial and sporadic mouse models of malignant GAC blocks metastatic disease, including peritoneal carcinomatosis. Suppressing SMYD5 methylation of rpL40 inhibits human cancer cell and patient-derived GAC xenograft growth and renders them hypersensitive to inhibitors of PI3K and mTOR. Finally, combining SMYD5 depletion with PI3K-mTOR inhibition and chimeric antigen receptor T cell administration cures an otherwise lethal in vivo mouse model of aggressive GAC-derived peritoneal carcinomatosis. Together, our work uncovers a ribosome-based epigenetic mechanism that facilitates the evolution of malignant GAC and proposes SMYD5 targeting as part of a potential combination therapy to treat this cancer.

Injectable Nanocomposite Hydrogels Improve Intraperitoneal Co-delivery of Chemotherapeutics and Immune Checkpoint Inhibitors for Enhanced Peritoneal Metastasis Therapy.

Intraperitoneal co-delivery of chemotherapeutic drugs (CDs) and immune checkpoint inhibitors (ICIs) brings hope to improve treatment outcomes in patients with peritoneal metastasis from ovarian cancer (OC). However, current intraperitoneal drug delivery systems face issues such as rapid drug clearance from lymphatic drainage, heterogeneous drug distribution, and uncontrolled release of therapeutic agents into the peritoneal cavity. Herein, we developed an injectable nanohydrogel by combining carboxymethyl chitosan (CMCS) with bioadhesive nanoparticles (BNPs) based on polylactic acid-hyperbranched polyglycerol. This system enables the codelivery of CD and ICI into the intraperitoneal space to extend drug retention. The nanohydrogel is formed by cross-linking of aldehyde groups on BNPs with amine groups on CMCS via reversible Schiff base bonds, with CD and ICI loaded separately into BNPs and CMCS network. BNP/CMCS nanohydrogel maintained the activity of the biomolecules and released drugs in a sustained manner over a 7 day period. The adhesive property, through the formation of Schiff bases with peritoneal tissues, confers BNPs with an extended residence time in the peritoneal cavity after being released from the nanohydrogel. In a mouse model, BNP/CMCS nanohydrogel loaded with paclitaxel (PTX) and anti-PD-1 antibodies (αPD-1) significantly suppressed peritoneal metastasis of OC compared to all other tested groups. In addition, no systemic toxicity of nanohydrogel-loaded PTX and αPD-1 was observed during the treatment, which supports potential translational applications of this delivery system.

[Treatment strategies of cytoreductive surgery plus intraperitoneal hyperthermic chemotherapy for gastric cancer with peritoneal metastasis: a systematic review].

Peritoneal metastasis in gastric cancer is associated with rapid disease progression. Hyperthermic intraoperative peritoneal chemotherapy (HIPEC) done immediately after cytoreductive surgery (CRS) has become an important treatment for peritoneal metastasis in gastric cancer patients. However, different treatment options for HIPEC exist with potential influence on survival rates and prognosis in patients, exist. These treatment options include open or closed abdomen technique, perfusion solution, number of catheters, temperature, duration, and drug regimens. This paper aims to provide more evidence on standardization of HIPEC treatment options and technologies by systematically reviewing different drug regimens and technical approaches. The study included 2 randomized controlled trials, 3 phase I/II clinical trials, 2 prospective cohort studies, and 34 retrospective cohort studies, involving 1511 patients. The most common HIPEC option is to dissolve 50-75 mg/m2 of Cisplatin and 30-40 mg/m2 of Mitomycin C in 3-4 L saline solution at 42-43℃. After gastrointestinal anastomosis, 2-3 catheters are used in the HIPEC system with a perfusion flow rate of 500 ml/min. The duration is 60-90 minutes. Anastomotic leakage was low in studies where HIPEC was performed after gastrointestinal anastomosis. The utilization of open HIPEC and a two-drug regimen resulted in improved overall survival rates. The future development of HIPEC aims to enhance tumor-specific therapy by optimizing various aspects, such as identifying the safest and most effective chemotherapy regimens, refining patient selection criteria, and improving perioperative care.