Pressurised intraperitoneal aerosol chemotherapy: rationale, evidence, and potential indications

Repeat Diagnostic Laparoscopy After Chemotherapy is Useful in Patient Selection for Conversion to Cytoreductive Surgery for Initially Unresectable Colorectal and Appendiceal Peritoneal Metastases: A Retrospective Cohort Study

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) enable effective management of colorectal and appendiceal peritoneal metastases (CAPM) despite high morbidity. This study aimed to evaluate the role of repeat diagnostic laparoscopy (rDL) after systemic ± intraperitoneal chemotherapy in the management of initially unresectable CAPM.

METHODS

This retrospective cohort study included 70 consecutive patients with CAPM who underwent initial diagnostic laparoscopy (iDL). Patients with inoperable or equivocal CAPM underwent chemotherapy followed by rDL to assess the treatment response and possibility of conversion to CRS and HIPEC.

RESULTS

Cytoreductive surgery was deemed feasible for 29 patients and unlikely or equivocal for 41 patients based on iDL. Of the 29 resectable patients, 24 successfully underwent CRS and HIPEC after neoadjuvant chemotherapy. Among the 41 patients initially considered unresectable, 16 were deemed operable based on rDL after chemotherapy, and CRS and HIPEC were achieved for 14 patients (conversion). The median peritoneal cancer index was significantly reduced after chemotherapy for the 14 "conversion" patients, from 16 based on iDL to 11 based on rDL (p < 0.05). The conversion rate was 34% (14/41), with a 5-year survival rate of 14%. Treatment with CRS and HIPEC was achieved for 38 of 45 patients deemed operable based on either iDL or rDL (worst-case estimated positive predictive value, 84%).

CONCLUSION

Diagnostic laparoscopy is useful in predicting the likelihood of achieving CRS for patients with CAPM. Despite inoperability based on iDL, patients should be considered for rDL after chemotherapy to assess the possibility of conversion to CRS and HIPEC.

Pressurised intraperitoneal aerosol chemotherapy (PIPAC): the first Australian experience

Objectives

Pressurised intraperitoneal aerosol chemotherapy (PIPAC) is a novel surgical technique for patients with peritoneal metastases not amenable to curative treatment. PIPAC delivers pressurised aerosolised chemotherapy using a hyperbaric capnoperitonem established laparoscopically. This study sought to investigate the feasibility and safety of PIPAC in an Australian population.

Methods

We undertook a cohort analysis of prospectively-collected data on patients undergoing PIPAC across two Australian hospitals. Participants were planned to have three PIPAC procedures, each 6 weeks apart. Study outcomes included post-operative complications including 30-day mortality, length of stay (LOS) and patient quality of life (EORTC QLQ-C30 scores).

Results

18 patients underwent 50 completed procedures. 13 patients had two or more PIPACs. The most common primary malignancy was colorectal cancer (n=8), followed by gastric cancer (n=4), appendiceal cancer (n=4) and mesothelioma (n=2). One grade four but no grade five complications occurred, with zero 30-day mortality. Median LOS was 1 day. Mean EORTC QLQ-C30 score increased from 47.8 at baseline to 53 post second PIPAC. Due to the heterogeneity of our cohort, survival analysis and statistical comparisons were unable to be made.

Conclusion

PIPAC is feasible, safe and well tolerated in an Australian population with a lack of severe complications and zero 30 day mortality. Due to the small number of patients and the heterogeneity of our study's sample, it was not possible to perform survival analysis. The study is nonetheless valuable as the first investigation of implementation of PIPAC in Australia.

Hyperthermic Intrathoracic Chemotherapy Modulates the Immune Microenvironment of Pleural Mesothelioma and Improves the Impact of Dual Immune Checkpoint Inhibition

Pleural mesothelioma is a fatal disease with limited treatment options. Recently, pleural mesothelioma management has improved with the development of immune checkpoint inhibitors (ICI). In first-line therapy, dual PD-1 and CTLA-4 blockade enhances tumor control and patient survival compared with chemotherapy. Unfortunately, only a fraction of patients is responsive to immunotherapy, and approaches to reshape the tumor immune microenvironment and make ICIs more effective are urgently required. In this study, we evaluated the effect of hyperthermic intrathoracic chemotherapy (HITOC), a treatment that combines fever-range hyperthermia with local intrapleural cisplatin chemotherapy, on the tumor immune microenvironment and response to ICIs. To do this, we developed a murine pleural mesothelioma model of HITOC. We found that HITOC significantly improved tumor control and animal survival through a mechanism involving the development of a cytotoxic immune response. Additionally, HITOC enhanced immune checkpoint expression by T lymphocytes and synergized with dual PD-1 and CTLA-4 inhibition, leading to further improvement in animal survival. Finally, the analysis of peritoneal mesothelioma patient samples treated by pressurized intraperitoneal aerosol chemotherapy revealed a similar immunomodulation. In conclusion, HITOC remodels the tumor immune microenvironment of pleural mesothelioma by promoting T-cell infiltration into the tumor and could be considered in combination with ICIs in the context of a clinical trial.

Predictive Factors for the Discontinuation of Pressurized Intraperitoneal Aerosol Chemotherapy: Enhancing Patient Selection to Improve Oncological Outcomes-A Single-Center Experience

Background: Since 2011, Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) has emerged as a promising treatment option for patients with peritoneal surface malignancies (PSM) who are not eligible for cytoreductive surgery (CRS). Repeated minimal-invasive treatment is one of the key features and the current empirical standard treatment (ST) consists of at least three administrations over about three months. However, many patients are unable to complete the full course, limiting the potential benefits of PIPAC. Method: This retrospective, single-center study assessed the completion rate of ST and identified the main causes and predictive factors for discontinuation. This study also evaluated the feasibility, safety, and efficacy of PIPAC and investigated whether improved patient selection over the years has resulted in better oncological outcomes. Result: Data from 168 patients treated with PIPAC between January 2017 and March 2023 for a total of 336 procedures showed that only 29% completed ST. Multivariate analysis identified ascites >500 mL and a prior history of bowel obstruction as significant predictors of discontinuation. Conclusions: Patients with radiological or clinical signs of obstruction should not be considered for PIPAC treatment, and ascites increases the risk of incomplete treatment. Larger studies are eagerly awaited to corroborate these findings and refine the selection criteria by disease entity.

Evolution in the Surgical Management of Gastric Cancer Peritoneal Metastases

Despite therapeutic treatments and the growing utilization of multimodal therapies, gastric cancer (GC) remains a highly aggressive malignancy with high mortality worldwide. Much of the complexity in treating GC is due to the high incidence of peritoneal metastasis (PM), with mean overall survival typically ranging from 4 to 10 months. With current systemic therapy, targeted therapies, and immunotherapies continuing to remain ineffective for GC/PM, there has been a significant growing interest in intraperitoneal (IP) therapies for the treatment of GC/PM. In this review, we summarize the development of PM and evolving treatment strategies for GC/PM. Furthermore, we explore the various advancements and outcomes of IP therapies, including heated intraperitoneal chemotherapy (HIPEC), neoadjuvant HIPEC, and pressurized intraperitoneal aerosolized chemotherapy (PIPAC).

Macrophage-derived cathepsin L promotes epithelial-mesenchymal transition and M2 polarization in gastric cancer

BACKGROUND

Advanced gastric tumors are extremely prone to metastasize the in 20%-30% of gastric cancer, and patients have a poor prognosis despite systemic chemotherapy. Peritoneal metastases from gastric cancer usually indicate the end stage of the disease without curative treatment.

AIM

To peritoneal metastasis for facilitating clinical therapy are urgently needed.

METHODS

Immunohistochemical staining and immunofluorescence staining were used to demonstrate the high expression of cathepsin L (CTSL) in human gastric cancer tissues and its localization in cells. Lentivirus transfection was used to construct stable cell lines. Transwell invasion assays, wound healing assays, and animal tests were used to determine the relationships between CTSL and epithelial-mesenchymal transition (EMT) and tumorigenic potential in vivo.

RESULTS

We observed that macrophage-derived CTSL promoted gastric cancer cell migration and metastasis via the EMT pathway in vitro and in vivo, which involved macrophage polarization. Our findings suggest that macrophages improve extracellular matrix remodeling and hence facilitate tumor metastasis. Ablation of CTSL in macrophages within the tumor microenvironment may improve tumor therapy and the prognosis of patients with gastric cancer peritoneal metastasis.

CONCLUSION

In consideration of our findings, tumor-associated macrophage-derived CTSL is an important factor that promotes the metastasis and invasion of gastric cancer cells, and the targeting of CTSL may potentially improve the prognosis of patients with gastric cancer with peritoneal metastasis.

Efficacy and Insights from an Extensive Series of Cytoreductive Surgery for Peritoneal Neoplasms: A High-Volume Single-Center Experience

Background: Advances in cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC) have improved outcomes for selected patients with peritoneal surface malignancies (PSMs). Methods: This retrospective study analyzed 743 PSM patients treated at Fondazione Policlinico Universitario Agostino Gemelli from January 2016 to February 2024. The primary aim was to assess median overall survival (mOS), median disease-free survival (mDFS), and median progression-free survival (mPFS) stratified by tumor origin. Secondary outcomes examined the role of diagnostic laparoscopy in the management of PSMs and intra- and postoperative complications' rates. Results: A total of 1113 procedures were performed: 389 CRS, 370 PIPAC, and 354 diagnostic laparoscopies. Colorectal cancer was the predominant indication for CRS (52.4%), with a mOS of 52 months and mDFS of 22 months. Patients affected by gastric cancer undergoing CRS had a mOS of 18 months and a mDFS of 13 months, while PIPAC yielded a mOS of 9 months and a mPFS of 4 months. Among patients with pseudomyxoma peritonei undergoing CRS, the 5-year DFS rate was 64.1%, and OS rate was 89%. Patients affected by mesothelioma and treated with CRS exhibited a median OS of 43 months and a DFS of 26 months. Pancreatic and hepatobiliary cancers were treated with PIPAC, with a respective mOS of 12 and 8 months. Postoperative complications occurred in 12.6% of CRS, 3.2% of PIPAC, and 1.7% of diagnostic laparoscopies. High peritoneal cancer index (PCI), gastric resection, and blood loss over 500 mL were identified as risk factors for major complications in a multivariate analysis. Conclusions: Developing a highly experienced multidisciplinary team is crucial for delivering tailored treatment strategies which aim to achieve optimal oncological outcomes while preserving patients' quality of life.

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.

Hyperthermic intraperitoneal chemotherapy: Ideal and reality

Hyperthermic Intraperitoneal Chemoperfusion (HIPEC) is a new adjuvant therapy for the treatment of abdominal malignant tumors and metastases, which has shown great potential. The HIPEC technique can effectively kill residual lesions in the abdominal cavity through the synergistic sensitization effect of thermal chemotherapy and the circulating perfusion and washing effect of large volume perfusion fluid, thereby reducing the occurrence of malignant ascites and reducing the risk of postoperative recurrence and metastasis. However, there are still many problems in the practical operation of HIPEC, such as non-uniform distribution of perfusate temperature, inadequate perfusion due to the presence of 'dead space', incomplete cytoreductive surgery (CRS), instances of catheter obstruction during perfusate circulation, the lack of a uniform standard for selecting appropriate HIPEC techniques, occupational exposure of medical personnel during the HIPEC procedure, and the selection of HIPEC chemotherapy regimens for patients with various types of tumors. This article aims to summarize the problems encountered in the clinical practice of HIPEC, explore the problems that can be improved, and put forward some suggestions, so as to promote the further standardization and normalization of HIPEC technology.

A comprehensive overview of gastric cancer management from a surgical point of view

Despite advancements in medical care, surgical technologies, and the development of novel treatments over the past decade, the prognosis for patients with gastric cancer (GC) has only modestly improved. This is primarily due to the fact that the majority of patients are diagnosed at advanced stages or present with metastatic disease. Radical resection remains the cornerstone of potentially curative treatment, yet the overall 5-year survival rate remains below 35%. The management of GC varies globally, influenced by factors such as geographical disparities, patient comorbidities and performance status, surgical approaches, and available medical resources. Multidisciplinary collaboration and a multimodal treatment approach are essential for optimizing patient outcomes. Surgeons must stay updated on emerging surgical concepts and make informed decisions regarding patient selection, timing of intervention, and the adoption of appropriate surgical techniques to improve both quality of life and prognosis. This review aims to provide a surgical perspective on the management of GC across all stages, highlighting the importance of a comprehensive treatment approach. Endoscopic resection may be a viable option for early GC in patients with minimal risk of lymph node metastasis, particularly in elderly patients with high surgical risk or severe comorbidities. For advanced GC, neoadjuvant therapy followed by surgery could be a promising strategy to improve patient outcomes. Conversion surgery offers a potential survival benefit for patients who respond to treatment with tumor downstaging. The treatment of peritoneal carcinomatosis remains challenging; however, hyperthermic intraperitoneal chemotherapy combined with complete cytoreductive surgery or pressurized intraperitoneal aerosolized chemotherapy may prolong survival or improve quality of life in highly selected patients.

Emerging Treatment Modalities for Gastric Cancer With Macroscopic Peritoneal Metastases: A Systematic Review

Gastric cancer with macroscopic peritoneal metastases represents a major therapeutic challenge and is associated with a poor prognosis. This review aims to evaluate the efficacy and safety of new treatment modalities. A systematic search of PubMed was conducted to identify studies published between January 2014 and April 2024. Inclusion criteria were trials investigating novel therapies for gastric cancer with peritoneal metastases. Data on treatment efficacy, survival outcomes, and side effects were extracted.

PIPAC Pharmacologic and Clinical Data

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) emerged as an innovative intraperitoneal chemotherapy delivery system to overcome the issue of limited efficacy of systemic therapies to induce response in peritoneal malignancies. Promising results for patients with mesothelioma peritonei and peritoneal metastasis from gastric, ovarian, colorectal, pancreatic, and hepatobiliary tumors origin are changing the landscape for patients otherwise just facing palliative treatment. Ongoing trials will shed more light on the actual benefits of PIPAC.

Patient-reported outcomes during first-line palliative systemic therapy alternated with pressurized intraperitoneal aerosol chemotherapy for unresectable colorectal peritoneal metastases: a single-arm phase II trial (CRC-PIPAC-II)

BACKGROUND

The CRC-PIPAC-II study prospectively assessed bidirectional therapy (BT) consisting of first-line palliative systemic therapy and electrostatic precipitation oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy (ePIPAC-OX) in patients with unresectable colorectal peritoneal metastases (CPM). This study describes the exploration of patient-reported outcomes (PROs).

METHODS

In this phase II trial, 20 patients with isolated CPM were treated with up to three cycles of BT, each cycle consisting of two to three courses of systemic therapy, followed by ePIPAC-OX (92 mg/m2). Patients were asked to complete the EuroQoL EQ-5D-5L, EORTC QLQ-C30, and EORTC QLQ-CR29 questionnaires at baseline, during the first cycle of BT, and one and four weeks after each consecutive BT cycle. PRO scores were calculated and compared between baseline and each subsequent time point using linear-mixed modeling (LMM). PROs were categorized into symptom scales and function scales. Symptom scales ranged from 0 to 100, with 100 representing the maximum symptom load. Function scales ranged from 0 to 100, with 100 representing optimal functioning.

RESULTS

Twenty patients underwent a total of 52 cycles of bidirectional therapy. Most PROs (29 of 37, 78%) were not significantly affected during trial treatment. In total, only eight PROs (22%) were significantly affected during trial treatment: Six PROs (index value, global health status, emotional functioning, C30, appetite, and insomnia) showed transient improvement at different time points. Two PROs transiently deteriorated: pain initially improved during the first BT cycle [- 16, p < 0.001] yet worsened temporarily one week after the first two BT cycles (+ 20, p < 0.001; + 17, p = 0.004; respectively). Abdominal pain worsened temporarily one week after the first BT cycle (+ 16, p = 0.004), before improving again four weeks after treatment ended (- 10, p = 0.004). All significant effects on Pros were clinically significant and all deteriorations in PROs were of temporary nature.

DISCUSSION

Patients undergoing BT for unresectable CPM had significant, but reversible alterations in several PROs. Most affected PROs concerned improvements and only two PROs showed deteriorations. Both deteriorated PROs returned to baseline after trial treatment and were of a temporary nature. These outcomes help to design future studies on the role of ePIPAC in the palliative setting.

Management of Peritoneal Surface Malignancies in Saudi Arabia: An Update

Peritoneal surface malignancies (PSM) are aggressive and associated with poor prognosis. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) have been used to treat PSM since 1990. In Saudi Arabia, the first HIPEC and pressurized intraperitoneal aerosol chemotherapy (PIPAC) were performed in 2008 and 2019, respectively. With increasing incidences of PSM in Saudi Arabia, the demand for such procedures has grown. This article outlines the status of PSM management in Saudi Arabia and its prospects.

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.

Third-line treatment and beyond in metastatic colorectal cancer: What do we have and what can we expect?

Colorectal cancer remains the third most common cancer worldwide and the second cause of cancer-related death. Treatment advances and precision oncological medicine for these tumours have been stalled in comparison to those for other common tumours such as lung and breast cancer. However, the recent publication of the SUNLIGHT trial results with the trifluridine/tipiracil (TAS-102)-bevacizumab combination and the irruption of new molecular targets with guided treatments have opened new possibilities in third-line metastatic colorectal cancer management. Anti-EGFR rechallenge, anti-HER2 targeted therapies or the promising results of Pressurised Intraperitoneal Aerosol Chemotherapy (PIPAC), are some of the available options that may modify what is presumably third-line colorectal treatment. Hereby, we present the evidence of the different treatment options in third-line colorectal cancer and beyond, as well as the possibilities of sequencing them.

Safety of pressurized intraperitoneal aerosolized chemotherapy in biliary cancer patients with peritoneal metastases

Biliary tract cancers are a rare diagnosis with a rising incidence. Up to 20% of patients have peritoneal metastases, resulting in symptoms of ascites, abdominal pain and potential bowel obstruction. A standard of care systemic treatment comprises gemcitabine, cisplatin and durvalumab (gem/cis/durva). However, the clinical benefit among patients with peritoneal metastases remains unknown. Pressurized intraperitoneal aerosolized chemotherapy (PIPAC) delivers chemotherapy directly to the peritoneal space, which could potentially improve efficacy with minimal systemic toxicity. We describe the design of a Phase I study investigating PIPAC with nab-paclitaxel plus systemic gem/cis/durva among biliary tract cancer patients with peritoneal metastases who have not received prior systemic treatment. The primary end point is safety of PIPAC with nab-paclitaxel in combination with systemic gem/cis/durva.Clinical Trial Registration: NCT05285358 (ClinicalTrials.gov).

First-line palliative systemic therapy alternated with oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy for unresectable colorectal peritoneal metastases: A single-arm phase II trial (CRC-PIPAC-II)

BACKGROUND

Palliative systemic therapy alternated with electrostatic precipitation oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy (ePIPAC) has never been prospectively investigated in patients with unresectable colorectal peritoneal metastases (CPM). The CRC-PIPAC-II study aimed to assess safety, feasibility and efficacy of such bidirectional therapy.

METHODS

This two-center, single-arm, phase II trial enrolled chemotherapy-naïve patients to undergo three treatment cycles, consisting of systemic therapy (CAPOX, FOLFOX, FOLFIRI, or FOLFOXIRI, all with bevacizumab) and oxaliplatin-based ePIPAC (92 mg/m2) with intravenous leucovorin (20 mg/m2) and 5-fluorouracil (400 mg/m2). Primary outcome were major treatment-related adverse events. Secondary outcomes included minor events, tumor response, progression-free survival (PFS) and overall survival (OS).

RESULTS

Twenty patients completed 52 treatment cycles. Fifteen major events occurred in 7 patients (35 %): 5 events (33 %) related to systemic therapy; 5 (33 %) related to ePIPAC; and 5 (33 %) were biochemical events. No treatment-related deaths occurred. All patients experienced minor events, mostly abdominal pain, nausea and peripheral sensory neuropathy. After treatment, radiological, pathological, cytological, and biochemical response was observed in 0 %, 88 %, 38 %, and 31 % of patients respectively. Curative surgery was achieved in one patient. Median PFS was 10.0 months (95 % confidence interval [CI] 8.0-13.0) and median OS was 17.5 months (95 % CI 13.0-not reached).

CONCLUSIONS

Combining palliative systemic therapy with oxaliplatin-based ePIPAC in patients with unresectable CPM was feasible and showed an acceptable safety profile. Treatment-induced response and survival are promising, yet further research is required to determine the additional value of ePIPAC to systemic therapy.

Impact of laparoscopic ultrasound during PIPAC directed treatment of unresectable peritoneal metastasis

Objectives

Laparoscopic ultrasound (LUS) combines both laparoscopy and ultrasound imaging of the peritoneum liver and retroperitoneum. LUS has not been described in treatments with pressurized intraperitoneal aerosol chemotherapy (PIPAC). We present our experience with LUS in patients undergoing PIPAC.

Methods

Retrospective study of LUS findings from the prospective PIPAC-OPC2 trial. Main outcome was changes in overall treatment strategy due to LUS findings.

Results

PIPAC-OPC2 included 143 patients of which 33 patients were treated with electrostatic precipitation PIPAC. Nine patients were excluded due to primary non-access. During PIPAC 1, LUS was performed in 112 of 134 (84 %) PIPAC procedures and changed overall treatment strategy in one patient due to detection of multiple liver metastases unseen by baseline CT. During PIPAC 2 and 3 LUS was performed in 59 of 104 (57 %) and 42 of 78 (54 %) PIPAC procedures, respectively. Throughout PIPAC 1-3, LUS also detected pathological lymph nodes in 16 patients, and focal liver lesions in another four patients of uncertain origin. No further examinations were performed in these patients, and the overall treatment strategy was not changed according to the PIPAC-OPC2 protocol. One patient had a splenic capsule rupture related to the LUS itself. This was managed conservatively.

Conclusions

LUS may be safely performed during PIPAC. However, LUS has limited clinical impact in patients scheduled for PIPAC, and cannot be recommended as a routine procedure when performing PIPAC.

PIPAC in patients with peritoneal metastases from gastrointestinal tract (PIPOX01): An open label, non-comparative phase 1/2 dose escalation and expansion trial

BACKGROUND

Despite modern systemic chemotherapy, survival remains poor for patients with advanced isolated peritoneal metastases from the gastrointestinal tract. We aimed to assess the safety and efficacy of pressurized intraperitoneal aerosol chemotherapy (PIPAC) with oxaliplatin.

PATIENTS AND METHODS

We conducted a phase 1/2, open label, non-comparative, dose escalation and expansion trial of PIPAC with oxaliplatin in patients with a peritoneal cancer index (PCI) of more than 5, 13 and 15 for respectively a gastric, small bowel and colorectal primary cancer, and who had received at least three months of systemic chemotherapy. PIPAC cycle lengths were 4-6 weeks with systemic chemotherapy allowed 15 days after each PIPAC. PCI and oxaliplatin tumor concentration were assessed every PIPAC cycle. The main endpoints were tolerability, tumor response, and survival.

RESULTS

Between 2017 and 2020, 34 patients were enrolled in three centers, in this phase 1/2 study, of whom 25 were evaluable at the recommended dose determined in the phase I trial (90 mg/m2 plus systemic 5-FU). Before inclusion, patients received a median of 2 [1-4] chemotherapy lines and had a median PCI of 22.5 [7-29]. At this dose, the safety profile showed acceptable tolerability. Eight patients (32 %) had grade 3/4 treatment-related adverse events. Minor (grade 1/2) adverse events were mainly abdominal pain (n = 19, 76 %) and nausea (n = 16, 64 %). Median PFS was 6.1 months and median OS was 13 months.

CONCLUSION

In patients with advanced and refractory peritoneal metastasis, PFS of 6.1 months is encouraging. A prospective randomized phase II study is required.

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.

Combined Nabpaclitaxel pressurized intraPeritoneal aerosol chemotherapy with systemic Nabpaclitaxel-Gemcitabine chemotherapy for pancreatic cancer peritoneal metastases: protocol of single-arm, open-label, phase II trial (Nab-PIPAC trial)

Objectives

Current therapies show limited efficacy against peritoneal metastases (PM) from pancreatic cancer. Pressurized intra-peritoneal aerosol chemotherapy (PIPAC) has emerged as a novel intraperitoneal drug delivery method. Recently, a dose-escalation study identified the safe dose of Nabpaclitaxel for PIPAC administration, an ideal intraperitoneal chemotherapy agent against pancreatic cancer. Combining systemic NabPaclitaxel-Gemcitabine with NabPaclitaxel-PIPAC may enhance disease control in pancreatic cancer patients with PM.

Methods

The Nab-PIPAC trial is a single-center, prospective, open-label, phase II study (ClinicalTrials.gov identifier: NCT05371223). Its primary goal is to evaluate the antitumor activity of the combined treatment based on Disease Control Rate (DCR) using RECISTv.1.1 criteria. Secondary objectives include feasibility, safety, pathological response, progression-free and overall survival, nutritional status, quality of life, pharmacokinetics of NabPaclitaxel-PIPAC, and PM molecular evolution via translational research. The treatment protocol consists of three courses, each with two cycles of intravenous NabPaclitaxel-Gemcitabine and one cycle of NabPaclitaxel-PIPAC, with standard metastatic pancreatic cancer doses for the former and 112.5 mg/m2 for the latter. Sample size follows Simon's two-stage design: 12 patients in stage one and 26 in stage two (80 % power, 0.1 alpha).

Results

Partial results will be available after first stage enrollment.

Conclusions

This trial aims to determine the antitumor efficacy and safety of combining NabPaclitaxel-PIPAC with systemic NabPaclitaxel-Gemcitabine in pancreatic cancer patients with PM.

Enhancing ovarian cancer treatment with maleimide-modified Pt(IV) prodrug nanoparticles

The limitations of platinum in ovarian cancer therapy, such as poor solubility and significant side effects, often lead to suboptimal therapeutic outcome and mortality. In this study, we have developed a novel approach utilizing biodegradable polymeric nanoparticles as a drug delivery system (NDDS), loaded with advanced platinum (IV) (Pt(IV)) prodrugs. A key feature of our approach is the enhancement of nanoparticles with maleimide, a modification hypothesized to significantly boost tumor tissue accumulation. When tested in mouse models of orthotopic and peritoneal metastasis ovarian cancer, these maleimide-modified nanoparticles are anticipated to show preferential accumulation in tumor tissues, enhancing therapeutic efficiency and minimizing systemic drug exposure. Our findings demonstrate that the maleimide-modified Pt(IV)-loaded NDDSs significantly reduce tumor burden in comparison to traditional cisplatin therapy, while simultaneously reducing adverse side effects. This leads to markedly improved survival rates in models of peritoneal metastasis ovarian cancer, offering a promising new direction in the treatment of this challenging disease.

How to Implement Pressurized Intraperitoneal Aerosol Chemotherapy into a National Health System Scenario: A Single-Center Retrospective Analysis of Costs and Economic Sustainability at a High-Volume Italian Hospital

PIPAC is a new surgical procedure and a viable treatment option for PSM patients, due to promising therapeutic outcomes, minimal invasiveness, limited surgical morbidity, and systemic toxicity side effects. However, its implementation throughout hospitals is hard to obtain due to its fragile economical sustainability. A retrospective health economic analysis was conducted in order to evaluate the cost of hospitalization for patients undergoing PIPAC treatment at Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, in Rome. The average cost of a PIPAC procedure was defined based on the cost of surgery (cost of surgical material, operating room, intraperitoneal chemotherapy), hospital stay, diagnostic examinations, and drugs used during the stay. A total of 493 PIPAC procedures were performed on 222 patients with peritoneal metastases or primary peritoneal cancer from 2017 to 2023. Since the mean remuneration for each PIPAC hospitalization is €5916 and the mean expenditure per hospitalization is €6538, this results in an operating profit per PIPAC hospitalization of -€622. The reimbursement of PIPAC treatment by the Italian National Health System currently only partially covers the hospital's costs. Development of specific codes and adequate reimbursement for PIPAC by recognizing this procedure as a proper treatment for peritoneal carcinomatosis is essential.

Efficacy of Hyperthermic Pressurized Intraperitoneal Aerosol Chemotherapy in an In Vitro Model Using a Human Gastric Cancer AGS Cell Line and an Abdominal Cavity Model

PURPOSE

Peritoneal carcinomatosis (PC) presents a major challenge in the treatment of late-stage, solid tumors, with traditional therapies limited by poor drug penetration. We evaluated a novel hyperthermic pressurized intraperitoneal aerosol chemotherapy (HPIPAC) system using a human abdominal cavity model for its efficacy against AGS gastric cancer cells.

MATERIALS AND METHODS

A model simulating the human abdominal cavity and AGS gastric cancer cell line cultured dishes were used to assess the efficacy of the HPIPAC system. Cell viability was measured to evaluate the impact of HPIPAC under 6 different conditions: heat alone, PIPAC with paclitaxel (PTX), PTX alone, normal saline (NS) alone, heat with NS, and HPIPAC with PTX.

RESULTS

Results showed a significant reduction in cell viability with HPIPAC combined with PTX, indicating enhanced cytotoxic effects. Immediately after treatment, the average cell viability was 66.6%, which decreased to 49.2% after 48 hours and to a further 19.6% after 120 hours of incubation, demonstrating the sustained efficacy of the treatment. In contrast, control groups exhibited a recovery in cell viability; heat alone showed cell viability increasing from 90.8% to 94.4%, PIPAC with PTX from 82.7% to 89.7%, PTX only from 73.3% to 74.8%, NS only from 90.9% to 98.3%, and heat with NS from 74.4% to 84.7%.

CONCLUSIONS

The HPIPAC system with PTX exhibits a promising approach in the treatment of PC in gastric cancer, significantly reducing cell viability. Despite certain limitations, this study highlights the system's potential to enhance treatment outcomes. Future efforts should focus on refining HPIPAC and validating its effectiveness in clinical settings.

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in the Treatment of Gastric Cancer: Feasibility, Efficacy and Safety-A Systematic Review and Meta-Analysis

Background: Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an emerging technique for delivering chemotherapy directly to the peritoneum via a pressurized aerosol. Its growing attention stems from its effectiveness in treating peritoneal carcinomatosis (PC) originating from various primary tumors, with gastric cancer (GC) being among the most prevalent. This study aimed to systematically investigate PIPAC's therapeutic role in gastric cancer peritoneal metastasis (GCPM). Methods: The systematic review and meta-analysis followed the PRISMA 2020 guidelines, searching Pubmed, Web of Science, and SCOPUS databases. The meta-analysis of relative risks and mean differences compared patients undergoing one or two PIPAC sessions with those completing three or more, assessing various outcomes. Results: Eighteen studies underwent qualitative analysis, and four underwent quantitative analysis. Patients with three or more PIPAC procedures had shorter hospital stays (MD = -1.2; 95%CI (-1.9; -0.5); p < 0.001), higher rates of histopathological response (RR = 1.77, 95%CI 1.08; 2.90; p = 0.023), and significantly improved overall survival (MD = 6.0; 95%CI 4.2; 7.8; p < 0.001). Other outcomes showed no significant differences. Conclusions: PIPAC demonstrated efficacy in carefully selected patients, enhancing histopathologic response rates and overall survival without prolonging hospital stays. This study underscores the necessity for randomized controlled trials and precise selection criteria to refine PIPAC's implementation in clinical practice.

Outcome of patients with peritoneal metastasis from ovarian cancer treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC)

Objectives

There are few data on Pressurized IntraPeritoneal Aerosol Chemotherapy with cisplatin and doxorubicin (PIPAC C/D) in women with primary unresectable or recurrent platinum-resistant peritoneal metastasis (PM) from ovarian cancer (OC). We evaluated survival, histological and cytological response, Quality of Life (QoL) and toxicity after PIPAC C/D in these patients.

Methods

Retrospective analysis of patients from the prospective PIPAC-OPC1 and -OPC2 studies. The histological response was evaluated by the Peritoneal Regression Grading Score (PRGS). QoL questionnaires were collected at baseline and after third PIPAC or 60 days. Adverse events were collected until 30 days after the last PIPAC. Demographic and survival data were analysed based on intention to treat. Response, QoL and toxicity were analysed per protocol (≥1 PIPAC).

Results

Twenty-nine patients were included. Five patients (17 %) were non-accessible at PIPAC 1. One patient was excluded due to liver metastases at PIPAC 1. Thus, 23 patients had 76 PIPACs (median 2, range 1-12). Median overall survival was 8.2 months (95 % CI 4.4-10.3) from PIPAC 1. Biopsy data were available for 22 patients, and seven (32 %) patients had a major/complete histological response (PRGS≤2) at PIPAC 3. No cytological conversions were registered. Symptoms and function scores worsened, while emotional scores improved. Three patients had severe adverse reactions (two ileus, one pulmonary embolism); no life-threatening reactions or treatment-related mortality was observed.

Conclusions

PIPAC C/D was feasible and induced histological regression in a substantial proportion of patients with platinum-resistant PM from OC. Larger studies are needed to evaluate impact on survival.

Standardizing eligibility and patient selection for Pressurized Intraperitoneal Aerosol Chemotherapy: A Delphi consensus statement

INTRODUCTION

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is a procedure for minimally invasive drug administration in patients with peritoneal metastasis. Previous studies have emphasized the importance of uniformity in treatment protocols and standardization of this practice. This study aimed to reach a consensus on eligibility, patient selection, and choice of chemotherapy for PIPAC.

METHODS

A three-round modified Delphi study was conducted. A steering group formulated a list of baseline statements, addressing the objectives. The steering group consisted of seven expert surgical and medical oncologists. Available evidence and published key opinions were critically reviewed. An international expert panel scored those statements on a 4-point Likert scale. The statements were submitted electronically and anonymously. Consensus was reached if the agreement rate was ≥75%. A minimum Cronbach's alpha of >0.8 was set.

RESULTS

Forty-five (45/58; 77.6%) experts participated and completed all rounds. Experts were digestive surgeons (n = 28), surgical oncologists (n = 7), gynecologists (n = 5), medical oncologists (n = 4), and one clinical researcher. Their assessment of 81 preliminary statements in the first round resulted in 41 consolidated statements. In round two, consensus was reached on 40 statements (40/41; 97.6%) with a consensus of ≥80% for each individual statement. In the third round, 40 statements were unanimously approved as definitive. The choice of first- and second-line chemotherapy remained controversial and could not reach consensus.

CONCLUSIONS

This International Delphi study provides practical guidance on eligibility and patient selection for PIPAC. Ongoing trial data and long-term results that could contribute to the further standardization of PIPAC are eagerly awaited.

Regional Therapy Approaches for Gastric Cancer with Limited Peritoneal Disease

PURPOSE

Despite advances in systemic therapy, outcomes of patients with gastric cancer (GC) peritoneal carcinomatosis (PC) remain poor, in part because of poor penetrance of systemic therapy into peritoneal metastasis due to the plasma-peritoneal barrier and anarchic intra-tumoral circulation. Hence, regional treatment approach with administration of chemotherapy directly into the peritoneal cavity (intraperitoneal, IP) under various conditions, combined with or without cytoreductive surgery (CRS) has remained an area of significant research interest. The purpose of this review is to provide high-level evidence for regional treatment approaches in the management of GCPC with limited peritoneal disease.

METHODS

A review of the current literature and ongoing clinical trials for regional IP therapies for GCPC was performed. Studies included in this review comprise of phase III randomized controlled trials, non-randomized phase II studies, high-impact retrospective studies, and active ongoing clinical trials for each available IP modality.

RESULTS

The three common IP approaches are heated intraperitoneal chemotherapy (HIPEC), normothermic intraperitoneal chemotherapy (NIPEC) and more recently introduced, pressurized intraperitoneal aerosolized chemotherapy (PIPAC). These IP approaches have been combined with systemic therapy and/or CRS with varying degrees of promising results, demonstrating evidence of improvements in survival rates and peritoneal disease control. Patient selection, optimization of systemic therapy, and completeness of cytoreduction have emerged as major factors influencing the design of contemporary and ongoing trials.

CONCLUSION

IP chemotherapy has a clear role in the management of patients with GCPC, and when combined with CRS in appropriately selected patients has the potential to significantly improve survival. Ongoing and upcoming IP therapy clinical trials hold great promise to shape the treatment paradigm for GCPC.

Neoplastic appendiceal mucinous lesions: a narrative review of the literature from an oncologist's perspective

Appendiceal mucinous lesions' classification and nomenclature has been modified several times along the last decades, reflecting their great heterogeneity and making difficult to compare results and draw conclusions. Despite its nearby origin, appendiceal mucinous lesions have a distinctive behaviour compared to colorectal cancer, including their molecular and genetic markers. Due to their low frequency, their management is not well standardised. However, surgery is considered the cornerstone of treatment. Their indolent behaviour has encouraged surgeons to apply more aggressive treatments, such as cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC), that may extend overall survival. Chemotherapy is reserved for unresectable and/or disseminated disease and could play a role in the adjuvant and neoadjuvant setting. Pressurised intraperitoneal aerosol chemotherapy (PIPAC) is recently emerging as a possible alternative for treatment in advanced disease although its results in long-term survival are lacking Hereby, we review the available evidence in the management of appendiceal mucinous lesions, including localised and disseminated disease, with a special emphasis on the oncological perspective, focusing on the lights and shadows of the systemic treatments.

Performance of different nebulizers in clinical use for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC)

OBJECTIVE

Technical ex-vivo comparison of commercial nebulizer nozzles used for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC).

METHODS

The performance of four different commercial nebulizer nozzles (Nebulizer; HurriChemTM; MCR-4 TOPOL®; QuattroJet) was analysed concerning: i) technical design and principle of operation, ii) operational pressure as function of the liquid flow rate, iii) droplet size distribution via laser diffraction spectrometry, iv) spray cone angle, spray cone form as well as horizontal drug deposition by image-metric analyses and v) chemical resistance via exposing to a cytostatic solution and chemical composition by means of spark optical emission spectral analysis.

RESULTS

The Nebulizer shows quasi an identical technical design and thus also a similar performance (e.g., mass median droplet size of 29 μm) as the original PIPAC nozzles (MIP/ CapnoPen). All other nozzles show more or less a performance deviation to the original PIPAC nozzles. The HurriChemTM has a similar design and principle of operation as the Nebulizer, but provides a finer aerosol (22 μm). The principle of operation of MCR-4 TOPOL® and QuattroJet differ significantly from that of the original PIPAC nozzle technology. The MCR-4 TOPOL® offers a hollow spray cone with significantly larger droplets (50 μm) than the original PIPAC nozzles. The QuattroJet generates an aerosol (22 μm) similar to that of the HurriChemTM but with improved spatial drug distribution.

CONCLUSION

The availability of new PIPAC nozzles is encouraging but can also have a negative impact if their performance and efficacy is unknown. It is recommended that PIPAC nozzles that deviate from the current standard should be subject to bioequivalence testing and implementation in accordance with the IDEAL-D framework prior to routine clinical use.

Pressurised Intraperitoneal Aerosolised Chemotherapy-Results from the First Hundred Consecutive Procedures

PIPAC is a new and promising technique for the intraperitoneal administration of chemotherapy. It can be used in patients with various peritoneal cancer metastases. It is mainly a palliative treatment, but there is some neoadjuvant treatment potential. We have operated on 41 patients with various intra-abdominal cancers. PIPAC was performed every 6 weeks. The indication was extension of peritoneal carcinomatosis beyond the criteria for cytoreductive surgery and HIPEC. The effect was evaluated according to the peritoneal cancer index, the peritoneal regression grading score and the amount of ascites. Complications were classified according to the Clavien-Dindo system. We have performed 100 PIPAC procedures. There were two major complications, classified as Clavien Dindo III (2%). The number of procedures varied from 1 to 6. Five patients switched to cytoreductive surgery and HIPEC, and one was indicated for the watch and wait strategy due to total regression according to PRGS. Three patients are still continuing treatment. The others stopped treatment mainly because of progression of the disease and loss of metastases. We observed a reduction in ascites production soon after PIPAC application. PIPAC is a safe and well-tolerated treatment modality. It is mainly a palliative treatment that can improve the quality of life by reducing the production of ascites, but in about 10% of cases, it can reduce the extent of the disease and allow for further radical treatment.

The role of cytoreductive surgery and HIPEC for the treatment of primary and secondary peritoneal malignancies-experience from a tertiary care center in Germany

PURPOSE

Peritoneal surface malignancies (PSM) are commonly known to have a dismal prognosis. Over the past decades, novel techniques such as cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and pressurized intraperitoneal aerosol chemotherapy (PIPAC) have been introduced for the treatment of PSM which could improve the overall survival and quality of life of patients with PSM. The decision to proceed with CRS and HIPEC is often challenging due the complexity of the disease, the extent of the procedure, associated side effects, and potential risks. Here, we present our experience with CRS and HIPEC to add to the ongoing discussion about eligibility criteria, technical approach, and expected outcomes and contribute to the evolution of this powerful and promising tool in the multidisciplinary treatment of patients with primary and secondary PSM.

METHODS

A single-center retrospective chart review was conducted and included a total of 40 patients treated with CRS and HIPEC from April 2020 to September 2022 at the University Hospital Münster Department of Surgery. All patients had histologically confirmed primary or secondary peritoneal malignancies of various primary origins.

RESULTS

Our study included 22 patients with peritoneal metastases from gastric cancer (55%), 8 with pseudomyxoma peritonei (20%), 4 with mesothelioma of the peritoneum (10%), and 6 patients with PSM originating from other primary tumor locations. Median PCI at time of cytoreduction was 4 (0-25). Completeness of cytoreduction score was 0 in 37 patients (92.5%), 1 in two patients (5%), and 2 in one patient (2.5%). Median overall survival across all patients was 3.69 years.

CONCLUSION

Complete cytoreduction during CRS and HIPEC can be achieved for patients with low PCI, for patients with high PCI in low-grade malignancies, and even for patients with initially high PCI in high-grade malignancies following a significant reduction of cancer burden due to extensive preoperative treatment with PIPAC and systemic chemotherapy.

Progress in Biological Research and Treatment of Pseudomyxoma Peritonei

Pseudomyxoma peritonei (PMP) is a rare disease characterized by extensive peritoneal implantation and mass secretion of mucus after primary mucinous tumors of the appendix or other organ ruptures. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is currently the preferred treatment, with excellent efficacy and safety, and is associated with breakthrough progress in long-term disease control and prolonged survival. However, the high recurrence rate of PMP is the key challenge in its treatment, which limits the clinical application of multiple rounds of CRS-HIPEC and does not benefit from conventional systemic chemotherapy. Therefore, the development of alternative therapies for patients with refractory or relapsing PMP is critical. The literature related to PMP research progress and treatment was searched in the Web of Science, PubMed, and Google Scholar databases, and a literature review was conducted. The overview of the biological research, treatment status, potential therapeutic strategies, current research limitations, and future directions associated with PMP are presented, focuses on CRS-HIPEC therapy and alternative or combination therapy strategies, and emphasizes the clinical transformation prospects of potential therapeutic strategies such as mucolytic agents and targeted therapy. It provides a theoretical reference for the treatment of PMP and the main directions for future research.

Hyperthermic pressurized intraperitoneal aerosol drug delivery system in a large animal model: a feasibility and safety study

BACKGROUND

We developed a novel drug delivery system called hyperthermic pressurized intraperitoneal aerosol chemotherapy (HPIPAC) that hybridized Hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC). The present study aims to assess the feasibility and safety of HPIPAC system in a large animal survival model.

METHODS

Eleven pigs (eight non-survival models and three survival models) were used in the experiment. The heat module in the HPIPAC controller circulates hyperthermic CO2 in a closed-loop circuit and creates gas-based dry intraperitoneal hyperthermia. Three 12 mm trocars were placed on the abdomen. The afferent CO2 tube wound with heat generating coil was inserted into a trocar, and the efferent tube was inserted into another trocar. Heated CO2 was insufflated and circulated in a closed circuit until the intra-abdominal and peritoneal surface temperature reached 42 °C. 100 ml of 5% dextrose in water was nebulized for 5 min and the closed-loop circulation was resumed for 60 min at 42 °C. Tissue biopsies were taken from several sites from the pigs in the survival model.

RESULTS

The average change in core temperature of the pigs was 2.5 ± 0.08 °C. All three pigs displayed no signs of distress, and their vital signs remained stable, with no changes in their diet. In autopsy, inflammatory and fibrotic responses at the biopsy sites were observed without serious pathologic findings.

CONCLUSIONS

We successfully proved the feasibility and safety of our novel HPIPAC system in an in-vivo swine survival model.

Peritoneal Metastatic Gastric Cancer: Local Treatment Options and Recommendations

Peritoneal metastasis is a common finding in patients with advanced gastric cancer. Beyond systemic chemotherapy, additive local treatments such as cytoreductive surgery and intraperitoneal chemotherapy are considered an inherent part of different multimodal treatment concepts for selected patients with peritoneal metastatic gastric cancer. This review article discusses the role of cytoreductive surgery (CRS) and intraperitoneal chemotherapy, including HIPEC, NIPS, and PIPAC, as additive therapeutic options with curative and palliative intent.

The Future of Interventions for Stage IV Colorectal Cancers

Future options for the management of stage IV colorectal cancer are primarily focused on personalized and directed therapies. Interventions include precision cancer medicine, utilizing nanocarrier platforms for directed chemotherapy, palliative pressurized intraperitoneal aerosol chemotherapy (PIPAC), adjunctive oncolytic virotherapy, and radioembolization techniques. Comprehensive genetic profiling provides specific tumor-directed therapy based on individual genetics. Biomimetic magnetic nanoparticles as chemotherapy delivery systems may reduce systemic side effects of traditional chemotherapy by targeting tumor cells and sparing healthy cells. PIPAC is a newly emerging option for patients with peritoneal metastasis from colorectal cancer and is now being used internationally, showing promising results as a palliative therapy for colorectal cancer. Oncolytic virotherapy is another emerging potential treatment option, especially when combined with standard chemotherapy and/or radiation, as well as immunotherapy. And finally, radioembolization with yttrium-90 ( 90 Y) microspheres has shown some success in treating patients with unresectable liver metastasis from colorectal cancer via selective arterial injection.

Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Metastases from Colorectal Cancer-An Overview of Current Status and Future Perspectives

Peritoneal metastases (PM) are observed in approximately 8% of patients diagnosed with colorectal cancer, either synchronously or metachronously during follow-up. PM often manifests as the sole site of metastasis. PM is associated with a poor prognosis and typically shows resistance to systemic chemotherapy. Consequently, there has been a search for alternative treatment strategies. This review focuses on the global evolution of the combined approach involving cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for the management of PM. It encompasses accepted clinical guidelines, principles for patient selection, surgical and physiological considerations, biomarkers, pharmacological protocols, and treatment outcomes. Additionally, it integrates the relevant literature and findings from previous studies. The role of CRS and HIPEC, in conjunction with other therapies such as neoadjuvant and adjuvant chemotherapy, is discussed, along with the management of patients presenting with oligometastatic disease. Furthermore, potential avenues for future development in this field are explored.

Enhanced Chemo-Immunotherapy Strategy Utilizing Injectable Thermosensitive Hydrogel for The Treatment of Diffuse Peritoneal Metastasis in Advanced Colorectal Cancer

Patients with colorectal cancer (CRC) and diffuse peritoneal metastasis (PM) are not eligible for surgical intervention. Thus, palliative treatment remains the standard of care in clinical practice. Systemic chemotherapy fails to cause drug accumulation at the lesion sites, while intraperitoneal chemotherapy (IPC) is limited by high clearance rates and associated complications. Given the poor prognosis, a customized OxP/R848@PLEL hydrogel delivery system has been devised to improve the clinical benefit of advanced CRC with diffuse PM. This system is distinguished by its simplicity, security, and efficiency. Specifically, the PLEL hydrogel exhibits excellent injectability and thermosensitivity, enabling the formation of drug depots within the abdominal cavity, rendering it an optimal carrier for IPC. Oxaliplatin (OxP), a first-line drug for advanced CRC, is cytotoxic and enhances the immunogenicity of tumors by inducing immunogenic cell death. Furthermore, OxP and resiquimod (R848) synergistically enhance the maturation of dendritic cells, promote the expansion of cytotoxic T lymphocytes, and induce the formation of central memory T cells. Moreover, R848 domesticates macrophages to an anti-tumor phenotype. OxP/R848@PLEL effectively eradicates peritoneal metastases, completely inhibits ascites production, and significantly prolongs mice lifespan. As such, it provides a promising approach to managing diffuse PM in patients with CRC without surgical indications.

What is long-term survival in patients with peritoneal metastasis from gastric, pancreatic, or colorectal cancer? A study of patients treated with systemic chemotherapy and pressurized intraperitoneal aerosol chemotherapy (PIPAC)

Objectives

A definition of long-term survival (LTS) in patients with peritoneal metastasis (PM) from gastric cancer (GC), pancreatic cancer (PC) or colorectal cancer (CRC) treated with systemic chemotherapy and pressurized intraperitoneal aerosol chemotherapy (PIPAC) is lacking. We aimed to define LTS and investigate characteristics and treatment response in patients who reached LTS in data from two prospective trials.

Methods

Retrospective study of patients with GC-, PC-, or CRC-PM from the prospective PIPAC-OPC1 and PIPAC-OPC2 studies. The definition of LTS was based on published systematic reviews and randomized controlled trials. LTS was defined at the time point where 25 % of the patients were alive in these studies. Histology based response was evaluated by the mean Peritoneal Regression Grading Score (PRGS) using biopsies obtained prior to PIPAC 3, and defined by a mean PRGS of ≤2.0 or a decrease of mean PRGS of ≥1, compared to baseline.

Results

LTS was defined at 21 (GC), 15 (PC), and 24 (CRC) months. Fifty-one (47.2 %) patients (nine GC, 17 PC, 25 CRC) reached LTS calculated from the date of PM diagnosis. All but one received palliative chemotherapy before PIPAC, and 37 % received bidirectional treatment. More than 90 % of the LTS patients had response according to PRGS. The mOS from PIPAC 1 was 23.3, 12.4, and 28.5 months for GC, PC, and CRC LTS patients.

Conclusions

Patients with PM from GC, PC, and CRC treated with systemic chemotherapy and PIPAC can reach LTS and most show histological response. Causality must be further investigated.

Reasons for stopping Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC): A retrospective study to improve future patient selection

To improve the prognosis and maintain quality of life in patients with peritoneal metastasis (PM), a novel treatment has been introduced-pressurized intraperitoneal aerosol chemotherapy (PIPAC). The majority of teams propose at least 3 PIPAC procedures. However, for many patients PIPAC is stopped after only one or two procedures. The aim of this study was to identify the reasons for stopping PIPAC after only one or two procedures and to establish a profile of poor candidates. This retrospective, multicenter cohort study included all patients who underwent PIPAC in three French expert centers between 2015 and 2021. A total of 268 PIPAC procedures were performed in 89 patients. Of them, 48.3% of patients underwent fewer than three procedures: 28.1% had one, 20.2% two and 51.7% three or more PIPAC procedures. The main reason for stopping PIPAC, regardless of the number of procedures, was disease progression, in 55.8% of cases. Other reasons for stopping PIPAC were non-access to the abdominal cavity (7.9%), conversion to cytoreductive surgery (13.5%), post-PIPAC adverse events (7.9%), patients' wishes (10.1%) and death (2.2%). In univariate analysis, patients who received fewer than three PIPACs less frequently had chemotherapy beforehand (91% vs 100%, p = 0.05), less frequently had bimodal treatment (70% vs 87%, p = 0.04), had more ascites (median 80 ml vs 50 ml, p = 0.05) and more frequently had carcinomatosic ascites (48.8% vs 23.9%, p < 0.01). Performing PIPAC alone in chemotherapy-naïve patients with ascites should be avoided.

Peritoneal Metastasis: A Dilemma and Challenge in the Treatment of Metastatic Colorectal Cancer

Peritoneal metastasis (PM) is a common mode of distant metastasis in colorectal cancer (CRC) and has a poorer prognosis compared to other metastatic sites. The formation of PM foci depends on the synergistic effect of multiple molecules and the modulation of various components of the tumor microenvironment. The current treatment of CRC-PM is based on systemic chemotherapy. However, recent developments in local therapeutic modalities, such as cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC), have improved the survival of these patients. This article reviews the research progress on the mechanism, characteristics, diagnosis, and treatment strategies of CRC-PM, and discusses the current challenges, so as to deepen the understanding of CRC-PM among clinicians.

Progress in the Treatment of Peritoneal Metastatic Cancer and the Application of Therapeutic Nanoagents

Peritoneal metastatic cancer is a cancer caused by the direct growth of cancer cells from the primary site through the bloodstream, lymph, or peritoneum, which is a difficult part of current clinical treatment. In the abdominal cavity of patients with metastatic peritoneal cancer, there are usually nodules of various sizes and malignant ascites. Among them, nodules of different sizes can obstruct intestinal movement and form intestinal obstruction, while malignant ascites can cause abdominal distension and discomfort, and even cause patients to have difficulty in breathing. The pathology and physiology of peritoneal metastatic cancer are complex and not fully understood. The main hypothesis is "seed" and "soil"; i.e., cells from the primary tumor are shed and implanted in the peritoneal cavity (peritoneal metastasis). In the last two decades, the main treatment modalities used clinically are cytoreductive surgery (CRS), systemic chemotherapy, intraperitoneal chemotherapy, and combined treatment, all of which help to improve patient survival and quality of life (QOL). However, the small-molecule chemotherapeutic drugs used clinically still have problems such as rapid drug metabolism and systemic toxicity. With the rapid development of nanotechnology in recent years, therapeutic nanoagents for the treatment of peritoneal metastatic cancer have been gradually developed, which has improved the therapeutic effect and reduced the systemic toxicity of small-molecule chemotherapeutic drugs to a certain extent. In addition, nanomaterials have been developed not only as therapeutic agents but also as imaging agents to guide peritoneal tumor CRS. In this review, we describe the etiology and pathological features of peritoneal metastatic cancer, discuss in detail the clinical treatments that have been used for peritoneal metastatic cancer, and analyze the advantages and disadvantages of the different clinical treatments and the QOL of the treated patients, followed by a discussion focusing on the progress, obstacles, and challenges in the use of therapeutic nanoagents in peritoneal metastatic cancer. Finally, therapeutic nanoagents and therapeutic tools that may be used in the future for the treatment of peritoneal metastatic cancer are prospected.

CO2-Driven Nebulization of pH-Sensitive Supramolecular Polymers for Intraperitoneal Hydrogel Formation and the Treatment of Peritoneal Metastasis

Because peritoneal metastasis (PM) from ovarian cancer is characterized by non-specific symptoms, it is often diagnosed at advanced stages. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) can be considered a promising drug delivery method for unresectable PM. Currently, the efficacy of intraperitoneal (IP) drug delivery is limited by the off-label use of IV chemotherapeutic solutions, which are rapidly cleared from the IP cavity. Hence, this research aimed to improve PM treatment by evaluating a nanoparticle-loaded, pH-switchable supramolecular polymer hydrogel as a controlled release drug delivery system that can be IP nebulized. Moreover, a multidirectional nozzle was developed to allow nebulization of viscous materials such as hydrogels and to reach an even IP gel deposition. We demonstrated that acidification of the nebulized hydrogelator solution by carbon dioxide, used to inflate the IP cavity during laparoscopic surgery, stimulated the in situ gelation, which prolonged the IP hydrogel retention. In vitro experiments indicated that paclitaxel nanocrystals were gradually released from the hydrogel depot formed, which sustained the cytotoxicity of the formulation for 10 days. Finally, after aerosolization of this material in a xenograft model of PM, tumor progression could successfully be delayed, while the overall survival time was significantly increased compared to non-treated animals.

The effect of electrostatic high pressure nebulization on the stability, activity and ex vivo distribution of ionic self-assembled nanomedicines

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is applied to treat unresectable peritoneal metastasis (PM), an advanced, end-stage disease with a poor prognosis. Electrostatic precipitation of the aerosol (ePIPAC) is aimed at improving the intraperitoneal (IP) drug distribution and tumor penetration. Also, the combination of nanoparticles (NPs) as drug delivery vehicles and IP aerosolization as administration method has been proposed as a promising tool to treat PM. There is currently limited knowledge on how electrostatic precipitation (ePIPAC) and high pressure nebulization (PIPAC) affects the performance of electrostatically formed complexes. Therefore, the stability, in vitro activity and ex vivo distribution and tissue penetration of negatively charged cisPt-pArg-HA NPs and positively charged siRNA-RNAiMAX NPs was evaluated following PIPAC and ePIPAC. Additionally, a multidirectional Medspray® nozzle was developed and compared with the currently used Capnopen® nozzle. For both NP types, PIPAC and ePIPAC did not negatively influence the in vitro activity, although limited aggregation of siRNA-RNAiMAX NPs was observed following nebulization with the Capnopen®. Importantly, ePIPAC was linked to a more uniform distribution and higher tissue penetration of the NPs aerosolized by both nozzles, independent on the NPs charge. Finally, compared to the Capnopen®, an increased NP deposition was observed at the top of the ex vivo model following aerosolization with the Medspray® nozzle, which indicates that this device possesses great potential for IP drug delivery purposes. STATEMENT OF SIGNIFICANCE: Aerosolized drug delivery in the peritoneal cavity holds great promise to treat peritoneal cancer. In addition, electrostatic precipitation of the aerosol to the peritoneal tissue is aimed at improving the drug distribution and tumor penetration. The combination of nanoparticles (NPs), which are nano-sized drug delivery vehicles, and aerosolization has been proposed as a promising tool to treat peritoneal cancer. However, there is currently limited knowledge on how electrostatic precipitation and aerosolization affect the performance of electrostatically formed NPs. Therefore, the stability, activity, distribution and penetration of negatively and positively charged NPs was evaluated after aerosolization and electrostatic precipitation. Additionally, to further optimize the local drug distribution, a multidirectional spray nozzle was developed and compared with the currently used nozzle.

Gynecologic oncology tumor board: the central role of the radiologist

This manuscript is a collaborative, multi-institutional effort by members of the Society of Abdominal Radiology Uterine and Ovarian Cancer Disease Focus Panel and the European Society of Urogenital Radiology Women Pelvic Imaging working group. The manuscript reviews the key role radiologists play at tumor board and highlights key imaging findings that guide management decisions in patients with the most common gynecologic malignancies including ovarian cancer, cervical cancer, and endometrial cancer.

Impact of positive microscopic resection margins (R1) after gastrectomy in diffuse-type gastric cancer

INTRODUCTION

Diffuse-type gastric cancer (DTGC) is associated with poor outcome. Surgical resection margin status (R) is an important prognostic factor, but its exact impact on DTGC patients remains unknown. The aim of this study was to assess the prognostic value of microscopically positive margins (R1) after gastrectomy on survival and tumour recurrence in DTGC patients.

METHODS

All consecutive DTGC patients from two tertiary centers who underwent curative oncologic gastrectomy from 2005 to 2018 were analyzed. The primary endpoint was overall survival (OS) for R0 versus R1 patients. Secondary endpoints included disease-free survival (DFS), recurrence patterns as well as the overall survival benefit of chemotherapy in this DTGC patient cohort.

RESULTS

Overall, 108 patients were analysed, 88 with R0 and 20 with R1 resection. Patients with negative lymph nodes and negative margins (pN0R0) had the best OS (median 102 months, 95% CI 1-207), whereas pN + R0 patients had better median OS than pN + R1 patients (36 months 95% CI 13-59, versus 7 months, 95% CI 1-13, p < 0.001). Similar findings were observed for DFS. Perioperative chemotherapy offered a median OS of 46 months (95% CI 24-68) versus 9 months (95% CI 1-25) after upfront surgery (p = 0.022). R1 patients presented more often early recurrence (< 12 postoperative months, 30% vs 8%, p = 0.002), however, no differences were observed in recurrence location.

CONCLUSION

DTGC patients with microscopically positive margins (R1) presented poorer OS and DFS, and early tumour recurrence in the present series. R0 resection should be obtained whenever possible, even if other adverse biological features are present.

Recent advances of AIE-active materials for orthotopic tumor phototheranostics

Cancer ranks as a leading threat to human life and health. Compared to conventional cancer treatments, phototheranostics shares the advantages of integrated diagnosis and therapy, outstanding therapeutic performance and good controllability. Amid diverse phototheranostic agents, small organic luminogens with aggregation-induced emission (AIEgen) tendency show predominant advantages in terms of superior photostability, large Stokes shifts, and boosted theranostic capacity as aggregates. In the past two decades, AIE-active materials have demonstrated formidable applications in disease theranostics, especially for tumors. This review mainly highlights the recent advances of orthotopic tumor phototheranostics mediated by AIEgens with a classification of different organs. Additionally, a brief discussion of current bottlenecks and future directions is outlined. We believe this review can deepen the understanding and spur more innovations on tumor theranostics by employing AIEgens. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

Bidirectional Approach with PIPAC and Systemic Chemotherapy for Patients with Synchronous Gastric Cancer Peritoneal Metastases (GCPM)

BACKGROUND

This study evaluated the efficacy of pressurized intraperitoneal aerosol chemotherapy (PIPAC) with systemic chemotherapy as a bidirectional approach for gastric cancer (GC) patients with synchronous peritoneal metastases (SPM).

METHODS

A retrospective analysis of a prospective PIPAC database was queried for patients who underwent a bidirectional approach between October 2019 and April 2022 at two high-volume GC surgery units in Italy (Verona and Siena). Surgical and oncological outcomes were analyzed.

RESULTS

Between October 2019 and April 2022, 74 PIPAC procedures in 42 consecutive patients with Eastern Cooperative Oncology Group performance status ≤2 were performed-32 patients treated in Verona and 10 in Siena. Twenty-seven patients (64%) were female and median age at first PIPAC was 60.5 years (I-III quartiles: 49-68 years). Median Peritoneal Cancer Index (PCI) was 16 (I-III quartiles: 8-26) and 25 patients (59%) had at least two PIPAC procedures. Major complications according to the Common Terminology Criteria for Adverse Events (CTCAE; 3 and 4) occurred in three (4%) procedures, and, according to the Clavien-Dindo classification (>3a), one (1%) severe complication occurred. There were no reoperations or deaths within 30 days. Median overall survival (mOS) from diagnosis was 19.6 months (range 14-24), and mOS from first PIPAC was 10.5 months (range 7-13). Excluding cases with very heavy metastatic peritoneal burden, with PCI from 2 to 26, treated with more than one PIPAC, mOS from diagnosis was 22 months (range 14-39). Eleven patients (26%) underwent curative-intent surgery after a bidirectional approach. R0 was achieved in nine (82%) patients and complete pathological response was obtained in three (27%) cases.

CONCLUSIONS

Patient selection is associated with bidirectional approach efficacy and feasibility for SPM GC treatment, which may allow potentially curative surgical radicalization in highly selected cases.