Modified scoring system for the quantitative assessment of histological regression in peritoneal carcinomatosis after pressurized intraperitoneal aerosol chemotherapy: A pilot study

Peritoneal carcinomatosis is one of the leading causes of death in patients with gastrointestinal cancer. Newer locoregional treatment concepts include pressurized intraperitoneal aerosol chemotherapy (PIPAC), the regional application of pressurized chemotherapeutic agents to the abdominal cavity, which is usually performed every 4 to 8 weeks. One of the main challenges of PIPAC therapy remains the objective assessment of treatment response. The present study describes a new scoring system to histologically assess the regression of peritoneal cancer following PIPAC therapy, quantitative assessment of histological regression in peritoneal carcinomatosis (QARP). Peritoneal biopsies from 27 patients with peritoneal metastases undergoing PIPAC were obtained and processed in a standardized fashion. Biopsies were scored according to the QARP grading system. The five-tiered system was graded as follows, Grade 0, no residual tumor cells with regressive changes present; grade 1, 1-25% viable tumor cells per tumor focus with regressive changes present; grade 2, 26-50% viable tumor cells per tumor focus with regressive changes present; grade 3, 51-75% viable tumor cells per tumor focus with few regressive changes; grade 4, >75% viable tumor cells per tumor focus with minimal or no regressive changes. Based on the new grading system, the study cohort was divided into QARP responders and QARP non-responders following PIPAC treatment. Higher QARP scores were significantly correlated with higher PCI scores (r=0.32; P=0.007). However, no difference in overall survival was detected between QARP responders and QARP non-responders. Further studies are required to ascertain the reproducibility and prognostic significance of QARP.

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.

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.

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.

[Contribution of intraperitoneal chemotherapy in the treatment of colorectal peritoneal carcinoma. HIPEC, PIPAC, state of the art and future directions]

After more than a decade of good results using the combination of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in the treatment of peritoneal carcinosis of colorectal origin, the PRODIGE7 study, which specifically evaluated the role of HIPEC, failed to show any superiority in terms of overall and disease-free survival for the CRS+HIPEC combination compared with CRS alone. This study constituted a radical change in the knowledge and therapeutic attitudes observed to date. After reviewing the literature and the consensus of national and international experts, a synthesis is provided, together with an outlook on the questions raised and the therapeutic trials and innovations of the near future. An analysis of recent advances due to the advent of a new technique, PIPAC, is also proposed, as well as a review of current therapeutic trials in this field.

Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) Applied to Platinum-Resistant Recurrence of Ovarian Tumor: A Single-Institution Experience (ID: PARROT Trial)

BACKGROUND

We aimed to investigate the therapeutic efficacy and safety of Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) in platinum-resistant recurrence of ovarian cancer and peritoneal carcinomatosis, while our secondary endpoint was to establish any changes in quality of life estimated via the EORTC QLQ-30 and QLQ-OV28 questionnaires.

METHODS

In this monocentric, single-arm, phase II trial, women were prospectively recruited and every 28-42 days underwent courses of PIPAC with doxorubicin 2.1 mg/m2 followed by cisplatin 10.5 mg/m2 via sequential laparoscopy.

RESULTS

Overall, 98 PIPAC procedures were performed on 43 women from January 2016 to January 2020; three procedures were aborted due to extensive intra-abdominal adhesions. The clinical benefit rate (CBR) was reached in 82% of women. Three cycles of PIPAC were completed in 18 women (45%), and 13 (32.5%) and 9 (22.5%) patients were subjected to one and two cycles, respectively. During two PIPAC procedures, patients experienced an intraoperative intestinal perforation. There were no treatment-related deaths. Nineteen patients showed no response according to the Peritoneal Regression Grading Score (PRGS) and 8 patients showed minor response according to the PRGS. Median time from ovarian cancer relapse to disease progression was 12 months (95% confidence interval [CI] 6.483-17.517), while the median overall survival was 27 months (95% CI 20.337-33.663). The EORTC QLQ-28 and EORTC QLQ-30 scores did not worsen during therapy.

CONCLUSIONS

PIPAC seems a feasible approach for the treatment of this subset of patients, without any impact on their quality of life. Since this study had a small sample size and a single-center design, future research is mandatory, such as its application in addition to systemic chemotherapy.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) with cisplatin and doxorubicin in patients with ovarian cancer: A systematic review

BACKGROUND

PIPAC consists in delivering normothermic chemotherapy solution directly into the peritoneal cavity as an aerosol under pressure. Currently PIPAC is considered as a palliative treatment for patients suffering from non-resectable peritoneal carcinomatosis. We performed a SR to assess tolerance and response of this novel method among patient with OC.

METHODS

We searched electronic database PubMed, Embase, Web of Science, Clinical Trials.gov. We only included clinical studies reporting PIPAC with cisplatin and doxorubicin in patients with ovarian cancer.

RESULTS

This systematic review included 4 studies. In 3 studies all patients were pretreated with cytoreductive surgery, in 1 study surgery was performed in 8/34 (23 %) patients. Mean PCI at first PIPAC procedure ranged from 16.3 to 19.6. All studies reported the proportion of patients with ascites at the first PIPAC with a pooled rate of 48,3 %. Pooled rate of CTCAE Grade 3 toxicity calculated on the total number of PIPAC was 6 % and Grade 4 was 0.9 %. One study reported two cases of small bowel perforation related or potentially related to PIPAC. On study reported a cumulative survival after 400 days of 62 % and a mean actuarial survival time of all patients who underwent PIPAC of 442 days. In another study the mean time to progression was 144 days (95 % CI 122-168 days).

CONCLUSION

This systematic review demonstrated that PIPAC with cisplatin and doxorubicin appear to have a good safety profile with low toxicity and encouraging trend in terms of overall survival.

Second annual report from the ISSPP PIPAC database

Objectives

To monitor the results of PIPAC directed therapy based on data from the International Society for the Study of the Pleura and Peritoneum (ISSPP) PIPAC database.

Methods

Analysis of data from patients entered between June 15th, 2020, and February 28th, 2023.

Results

Twelve centers reported 2,456 PIPAC procedures in 809 patients (median 2, range 1-18) with peritoneal metastasis (PM) from different primary tumors. Approximately 90 % had systemic chemotherapy prior to PIPAC. Twenty-eight percent were treated in prospective protocols. Overall non-access rate was 3.5 %. Concomitant surgical procedures were performed during PIPAC in 1.6 % of the patients. Median length of stay was 2 days. A total of 95 surgical complications were recorded, but only 22 % of these were graded ≥3b. Seventeen-hundred-and-three adverse events were noted, and 8 % were classified ≥3. The rate of complete or major histological response (peritoneal regression grade score, PRGS≤2) increased between the first and the third PIPAC in the group of patients who were evaluated by PRGS, and a PRGS ≤2 or a reduction of the mean PRGS of at least 1 between first and third PIPAC were observed in 80 %. Disease progression (50 %) or technical issues (19 %) were the most important reasons for stopping PIPAC treatment. Median overall survival from first PIPAC directed treatment varied from 10.7 months (CI 8.7-12.5) in gastric cancer to 27.1 months (16.4-50.5) in mesothelioma.

Conclusions

The ISSPP PIPAC database provides substantial real-world data supporting the use of PIPAC directed therapy in patients with PM from different primary tumors.

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.

PIPAC for Gastrointestinal Malignancies

The peritoneum is a common site of metastases for gastrointestinal tumors that predicts a poor outcome. In addition to decreased survival, peritoneal metastases (PMs) can significantly impact quality of life from the resulting ascites and bowel obstructions. The peritoneum has been a target for regional therapies due to the unique properties of the blood-peritoneum barrier. Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) have become accepted treatments for limited-volume peritoneal disease in appendiceal, ovarian, and colorectal malignancies, but there are limitations. Pressurized intraperitoneal aerosolized chemotherapy (PIPAC) improves drug distribution and tissue penetration, allowing for a minimally invasive application for patients who are not CRS/HIPEC candidates based on high disease burden. PIPAC is an emerging treatment that may convert the patient to resectable disease, and may increase survival without major morbidity, as indicated by many small studies. In this review, we discuss the rationale and benefits of PIPAC, as well as sentinel papers describing its application for gastric, colorectal, appendiceal, and pancreatobiliary PMs. While no PIPAC device has yet met FDA approval, we discuss next steps needed to incorporate PIPAC into neoadjuvant/adjuvant treatment paradigms, as well as palliative settings. Data on active clinical trials using PIPAC are provided.

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.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) with cisplatin and doxorubicin in combination with FOLFOX chemotherapy as a first-line treatment for gastric cancer patients with peritoneal metastases: single-arm phase II study

BACKGROUND

Gastric cancer (GC) remains among the most common and most lethal cancers worldwide. Peritoneum is the most common site for distant dissemination. Standard treatment for GC peritoneal metastases (PM) is a systemic therapy, but treatment outcomes remain very poor, with median overall survival ranging between 3-9 months. Thus, novel treatment methods are necessary. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is the most novel technique for intraperitoneal chemotherapy. Some preliminary data suggest PIPAC can achieve improved long-term outcomes in patients with GC PM, especially when used in combination with systemic chemotherapy. However, there is a lack of data from well-design prospective studies that would confirm the efficacy of PIPAC and systemic therapy combination for first-line treatment.

METHODS

This study is an investigator-initiated single-arm, phase II trial to investigate the efficacy of PIPAC combined with systemic FOLFOX (5-fluorouracil, oxaliplatin, leucovorin) as a first-line treatment for GC PM. The study is conducted in 2 specialized GC treatment centers in Lithuania. It enrolls GC patients with histologically confirmed PM without prior treatment. The treatment protocol consists of PIPAC with cisplatin (10.5 mg/m2 body surface in 150 mL NaCl 0.9%) and doxorubicin (2.1 mg/m2 in 50 mL NaCl 0.9%) followed by 2 cycles of FOLFOX every 6-7 weeks. In total 3 PIPACs and 6 cycles of FOLFOX will be utilized. The primary outcome of the study is the objective response rate (ORR) according to RECIST v. 1.1 criteria (Eisenhauer et al., Eur J Cancer 45:228-47) in a CT scan performed 7 days after the 4th cycle of FOLFOX. Secondary outcomes include ORR after all experimental treatment, PIPAC characteristics, postoperative morbidity, histological and biochemical response, ascites volume, quality of life, overall survival, and toxicity.

DISCUSSION

This study aims to assess PIPAC and FOLFOX combination efficacy for previously untreated GC patients with PM.

TRIAL REGISTRATION

NCT05644249. Registered on December 9, 2022.

Smart hydrogels delivered by high pressure aerosolization can prevent peritoneal adhesions

Postoperative peritoneal adhesions occur in the majority of patients undergoing intra-abdominal surgery and are one of the leading causes of hospital re-admission. There is an unmet clinical need for effective anti-adhesive biomaterials, which can be applied evenly across the damaged tissues. We examined three different responsive hydrogel types, i.e. a thermosensitive PLGA-PEG-PLGA, a pH responsive UPy-PEG and a shear-thinning hexapeptide for this purpose. More specifically, their potential to be homogeneously distributed in the peritoneal cavity by high pressure nebulization and prevent peritoneal adhesions was evaluated. Solutions of each polymer type could be successfully nebulized while retaining their responsive gelation behavior in vitro and in vivo. Furthermore, none of the polymers caused in vitro toxicity on SKOV3-IP2 cells. Following intraperitoneal administration, both the PLGA-PEG-PLGA and the hexapeptide hydrogels resulted in local inflammation and fibrosis and failed in preventing peritoneal adhesions 7 days after adhesion induction. In contrast, the pH sensitive UPy-PEG formulation was well tolerated and could significantly reduce the formation of peritoneal adhesions, even outperforming the commercially available Hyalobarrier® as positive control. To conclude, local nebulization of the bioresponsive UPy-PEG hydrogel can be considered as a promising approach to prevent postsurgical peritoneal adhesions.

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.

Descriptive review of current practices and prognostic factors in patients with ovarian cancer treated by pressurized intraperitoneal aerosol chemotherapy (PIPAC): a multicentric, retrospective, cohort of 234 patients

Introduction

Ovarian cancer (OC) is the primary cause of mortality in women diagnosed with gynecological cancer. Our study assessed pressurized intraperitoneal aerosol chemotherapy (PIPAC) as treatment for peritoneal surface metastases (PSM) from recurrent or progressive OC and conducted survival analyses to identify prognostic factors.

Material and methods

This retrospective cohort study, conducted across 18 international centers, analyzed the clinical practices of patients receiving palliative treatment for PSM from OC who underwent PIPAC. All patients were initially treated appropriately outside any clinical trial setting. Feasibility, safety, and morbidity were evaluated along with objective endpoints of oncological response. Multivariate analysis identified prognostic factors for OS and PFS.

Results

From 2015-2020, 234 consecutive patients were studied, from which 192 patients were included and stratified by platinum sensitivity for analysis. Patients with early recurrence, within one postoperative month, were excluded. Baseline characteristics were similar between the groups regarding platinum sensitivity (platinum sensitive (PS) and resistant (PR)), but chemotherapy frequency differed, as did PCI before PIPAC. Median PCI decreased in both groups after three cycles of PIPAC (PS 16 vs. 12, p < 0.001; PR 24 vs. 20, p = 0.009). Overall morbidity was 22%, with few severe complications (4-8%) or mortality (0-3%). Higher pathological response and longer OS (22 vs. 11m, p = 0.012) and PFS (12 vs. 7m, p = 0.033) were observed in the PS group. Multivariate analysis (OS/PFS) identified ascites (HR 4.02, p < 0.001/5.22, p < 0.001), positive cytology at first PIPAC (HR 3.91, p = 0.002/1.96, p = 0.035), and ≥ 3 PIPACs (HR 0.30, p = 0.002/0.48, p = 0.017) as independent prognostic factors of overall survival/progression-free survival.

Conclusions

With low morbidity and mortality rates, PIPAC is a safe option for palliative treatment of advanced ovarian cancer. Promising results were observed after 3 PIPAC, which did improve the peritoneal burden. However, further research is needed to evaluate the potential role of PIPAC as an independent prognostic factor.

Novel Multi-Modal Therapies and Their Prognostic Potential in Gastric Cancer

BACKGROUND

Gastric cancer has a poor prognosis and involves metastasis to the peritoneum in over 40% of patients. The optimal treatment modalities have not been established for gastric cancer patients with peritoneal carcinomatosis (GC/PC). Although studies have reported favourable prognostic factors, these have yet to be incorporated into treatment guidelines. Hence, our review aims to appraise the latest diagnostic and treatment developments in managing GC/PC.

METHODS

A systematic review of the literature was performed using MEDLINE, EMBASE, the Cochrane Review, and Scopus databases. Articles were evaluated for the use of hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurised intraperitoneal aerosolised chemotherapy (PIPAC) in GC/PC. A meta-analysis of studies reporting on overall survival (OS) in HIPEC and comparing the extent of cytoreduction as a prognostic factor was also carried out.

RESULTS

The database search yielded a total of 2297 studies. Seventeen studies were included in the qualitative and quantitative analyses. Eight studies reported the short-term OS at 1 year as the primary outcome measure, and our analysis showed a significantly higher OS for the HIPEC/CRS cohort compared to the CRS cohort (pooled OR = 0.53; p = 0.0005). This effect persisted longer term at five years as well (pooled OR = 0.52; p < 0.0001). HIPEC and CRS also showed a longer median OS compared to CRS (pooled SMD = 0.61; p < 0.00001). Three studies reporting on PIPAC demonstrated a pooled OS of 10.3 (2.2) months. Prognostic factors for longer OS include a more complete cytoreduction (pooled OR = 5.35; p < 0.00001), which correlated with a peritoneal carcinomatosis index below 7.

CONCLUSIONS

Novel treatment strategies, such as HIPEC and PIPAC, are promising in the management of GC/PC. Further work is necessary to define their role within the treatment algorithm and identify relevant prognostic factors that will assist patient selection.

Strategy for Oligometastatic Recurrence of Cardia Adenocarcinoma: Liver Radiofrequency Ablation Associated with PIPAC Inducing Response Permitting Cytoreductive Surgery and HIPEC

Management of oligometastatic disease (OMD) in esophagogastric junction cancer is complex due to anatomical location and adenocarcinoma pathway. Specific curative strategy is mandatory to increase survival. A multimodal approach combining surgery, systemic and peritoneal chemotherapy, radiotherapy, and radiofrequency could be envisaged. We report a strategy proposed for a 61-year-old male with cardia adenocarcinoma, initially treated with chemotherapy and superior polar esogastrectomy. He developed at later stage an OMD with peritoneal metastasis, single liver metastasis, and single lung metastasis. Considering that peritoneal metastases were unresectable at first, he was given multiple Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) with oxaliplatin, associated with intravenous docetaxel. Percutaneous radiofrequency ablation was performed during the first PIPAC procedure. Peritoneal response allowed a secondary Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy.

Pressurized intraperitoneal aerosol chemotherapy, reasons for interrupting treatment: a systematic review of the literature

Objectives

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) gives encouraging results in the treatment of peritoneal metastasis (PM). The current recommendations require at least 3 sessions of PIPAC. However, some patients do not complete the full treatment course and stop after only 1 or 2 procedures, hence the limited benefit. A literature review was performed, with search terms including "PIPAC" and "pressurised intraperitoneal aerosol chemotherapy."

Content

Only articles describing the causes for premature termination of the PIPAC treatment were analysed. The systematic search identified 26 published clinical articles related to PIPAC and reporting causes for stopping PIPAC.

Summary

The series range from 11 to 144 patients, with a total of 1352 patients treated with PIPAC for various tumours. A total of 3088 PIPAC treatments were performed. The median number of PIPAC treatments per patient was 2.1, the median PCI score at the time of the first PIPAC was 19 and the number of patients who did not complete the recommended 3 sessions of PIPAC was 714 (52.8%). Disease progression was the main reason for early termination of the PIPAC treatment (49.1%). The other causes were death, patients' wishes, adverse events, conversion to curative cytoreductive surgery and other medical reasons (embolism, pulmonary infection, etc…).

Outlook

Further investigations are necessary to better understand the causes for interrupting PIPAC treatment and also improving the selection of patients who are most likely to benefit from PIPAC.

Occupational Exposure during Intraperitoneal Pressurized Aerosol Chemotherapy Using Doxorubicin in a Pig Model

Background

This study evaluated occupational exposure levels of doxorubicin in healthcare workers performing rotational intraperitoneal pressurized aerosol chemotherapy (PIPAC) procedures.

Methods

All samples were collected during PIPAC procedures applying doxorubicin to an experimental animal model (pigs). All procedures were applied to seven pigs, each for approximately 44 min. Surface samples (n = 51) were obtained from substances contaminating the PIPAC devices, surrounding objects, and protective equipment. Airborne samples were also collected around the operating table (n = 39). All samples were analyzed using ultra-high performance liquid chromatography-mass spectrometry.

Results

Among the surface samples, doxorubicin was detected in only five samples (9.8%) that were directly exposed to antineoplastic drug aerosols in the abdominal cavity originating from PIPAC devices. The telescopes showed concentrations of 0.48-5.44 ng/cm² and the trocar showed 0.98 ng/cm² in the region where the spraying nozzles were inserted. The syringe line connector showed a maximum concentration of 181.07 ng/cm², following a leakage. Contamination was not detected on the surgeons' gloves or shoes. Objects surrounding the operating table, including tables, operating lights, entrance doors, and trocar holders, were found to be uncontaminated. All air samples collected at locations where healthcare workers performed procedures were found to be uncontaminated.

Conclusions

Most air and surface samples were uncontaminated or showed very low doxorubicin concentrations during PIPAC procedures. However, there remains a potential for leakage, in which case dermal exposure may occur. Safety protocols related to leakage accidents, selection of appropriate protective equipment, and the use of disposable devices are necessary to prevent occupational exposure.

PIPAC nebulizer: How to test the new devices in the market, expert recommendations

Pressurized intraperitoneal aerosol chemotherapy, named PIPAC, is now used in many centers around the world and as an intraperitoneal drug delivery system for treatment of peritoneal carcinomatosis. Recently, many of us have encountered problems during PIPAC procedures due to changes in material and production features of the original PIPAC nebulizer. Concomitantly, new PIPAC nebulizers proposed by other manufacturers are being launched on the market; which claim that they are the same as the original device in delivering PIPAC. However, these new devices are all different in terms of materials, technical characteristics and costs. We have considered that, to maintain the acquired results of PIPAC, we must ensure that the new systems are equivalent. The characteristics deemed essential by the expert group are as follows: 1: The nebulizer must be able to create droplets through an injector pressure between 10 and 20 bars, 2: The mean droplet size must be 3 micrometers, with 95% of the droplets between 0 and 10 micrometers, 3: The diffusion angle must be 70 degrees, which is the minimum.

Pressurised intraperitoneal aerosolised chemotherapy (PIPAC) for gastric cancer with peritoneal metastases: A systematic review by the PIPAC UK collaborative

INTRODUCTION

Gastric cancer with peritoneal metastases (GCPM) carries a poor prognosis. Pressurised Intraperitoneal Aerosolised Chemotherapy (PIPAC) offers pharmacokinetic advantages over intravenous therapy, resulting in higher chemotherapy concentrations in peritoneal deposits, and potentially reduced systemic absorption/toxicity. This review evaluates efficacy, tolerability and impact on quality of life (QOL) of PIPAC for GCPM.

METHODS

Following registration with PROSPERO (CRD42021281500), MEDLINE, EMBASE and The Cochrane Library were searched for PIPAC in patients with peritoneal metastases, in accordance with PRISMA standards RESULTS: Across 18 included reports representing 751 patients with GCPM (4 prospective, 11 retrospective, 3 abstracts, no phase III studies), median overall survival (mOS) was 8 - 19.1 months, 1-year OS 49.8-77.9%, complete response (PRGS1) 0-35% and partial response (PRGS2/3) 0-83.3%. Grade 3 and 4 toxicity was 0.7-25% and 0-4.1% respectively. Three studies assessing QOL reported no significant difference.

CONCLUSION

PIPAC may offer promising survival benefits, toxicity, and QOL for GCPM.

Treatment Response After Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) for Peritoneal Metastases of Colorectal Originf

The objective of this study is to analyze oncological outcomes of patients with peritoneal metastases (PM) of colorectal origin treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC).

Background

PIPAC has been demonstrated to be a feasible and safe novel treatment for patients with PM of various origins. Only small series reports on survival after PIPAC by disease entity.

Methods

International retrospective cohort study of consecutive patients with PM of colorectal origin. Outcome measures were overall survival (OS), radiological response according to Response Evaluation Criteria in Solid Tumors (RECIST), histological response (peritoneal regression grading score [PRGS]: complete response: 1-4: no response), change of peritoneal cancer index (PCI), and symptom control.

Results

Seventeen eligible centers compiled 256 non-selected patients (mean age 61 [50.6-69.2], 43% female) and 606 procedures. Sixty-three percent were treated after 2 lines of chemotherapy, median PCI at PIPAC1 was 18 (interquartile range [IQR] = 10-27). Median OS was 19.00 months (IQR = 12.9-29.8) from diagnosis and 9.4 months (IQR = 4.5-16.8) from PIPAC1. One hundred and four of 256 patients (40.6%) had ≥3 procedures (per protocol [pp]) with the following outcomes at PIPAC3: RECIST: 59.3% partial response/stable, 40.7% progression; mean PRGS: 2.1 ± 0.9. Median PCI was 21 (IQR = 15-29) at baseline and 20 (IQR = 12-27) at PIPAC3 (P = 0.02). Fifty-six (54%) and 48 (46%) patients were symptomatic at baseline and PIPAC3, respectively (P = 0.267). Median OS for the pp cohort was 11.9 months (IQR = 10.7-15.0) from PIPAC1. Independent predictors for survival were radiological response (HR = 3.0; 95% CI = 1.6-5.7) and no symptoms (HR = 4.5, 95% CI = 2.2-9.1) at PIPAC3.

Conclusions

Objective treatment response and encouraging survival were demonstrated after PIPAC for colorectal PM. Prospective registry data and comparative studies are now needed in to confirm these data.

The Role of Surgery in the Management of Gastric Cancer: State of the Art

Surgery still represents the mainstay of treatment of all stages of gastric cancer (GC). Surgical resections represent potentially curative options in the case of early GC with a low risk of node metastasis. Sentinel lymph node biopsy and indocyanine green fluorescence are novel techniques which may improve the employment of stomach-sparing procedures, ameliorating quality of life without compromising oncological radicality. Nonetheless, the diffusion of these techniques is limited in Western countries. Conversely, radical gastrectomy with extensive lymphadenectomy and multimodal treatment represents a valid option in the case of advanced GC. Differences between Eastern and Western recommendations still exist, and the optimal multimodal strategy is still a matter of investigation. Recent chemotherapy protocols have made surgery available for patients with oligometastatic disease. In this context, intraperitoneal administration of chemotherapy via HIPEC or PIPAC has emerged as an alternative weapon for patients with peritoneal carcinomatosis. In conclusion, the surgical management of GC is still evolving together with the multimodal strategy. It is mandatory for surgeons to be conscious of the current evolution of the surgical management of GC in the era of multidisciplinary and tailored medicine.

Management of peritoneal surface metastases from colorectal cancer: Cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, pressurized intraperitoneal chemotherapy, and beyond

This article provides a contemporary review of the current surgical management of peritoneal surface malignancy (PSM) of colorectal origin. A brief review of the founding history of surgical intervention for PSM is followed by a focused review of the level I evidence, current clinical questions, and evolving advancements. While not intended to address all the facets of PSM, this review aims to provide the reader with the essential knowledge and resources to effectively provide surgical care for carcinomatosis due to colorectal malignancies.

Assessment of Treatment Response after Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) for Appendiceal Peritoneal Metastases

Background The aim of this study was to analyse survival and surrogates for oncological response after PIPAC for appendiceal tumours. Methods This retrospective cohort study included consecutive patients with appendiceal peritoneal metastases (PM) treated in experienced PIPAC centers. Primary outcome measure was overall survival (OS) from the date of diagnosis of PM and from the start of PIPAC. Predefined secondary outcome included radiological response (RECIST criteria), repeat laparoscopy and peritoneal cancer index (PCI), histological response assessed by the Peritoneal regression grading system (PRGS) and clinical response. Results Final analysis included 77 consecutive patients (208 PIPAC procedures) from 15 centres. Median OS was 30 months (23.00-46.00) from time of diagnosis and 19 months (13.00-28.00) from start of PIPAC. 35/77 patients (45%) had ≥3 procedures (pp: per protocol). Objective response at PIPAC3 was as follows: RECIST: complete response 4 (11.4%), 11 (31.4%) partial/stable; mean PRGS at PIPAC3: 1.8 ± 0.9. Median PCI: 21 (IQR 18-27) vs. 22 (IQR 17-28) at baseline (p = 0.59); 21 (60%) and 18 (51%) patients were symptomatic at baseline and PIPAC3, respectively (p = 0.873). Median OS in the pp cohort was 22.00 months (19.00-NA) from 1st PIPAC. Conclusion Patients with PM of appendiceal origin had objective treatment response after PIPAC and encouraging survival curves call for further prospective evaluation.

Feasibility and Safety of Taxane-PIPAC in Patients with Peritoneal Malignancies-a Retrospective Bi-institutional Study

Taxanes have a favorable pharmacokinetic profile for intraperitoneal application. We report our initial experience with taxane-PIPAC (pressurized intraperitoneal chemotherapy) for unresectable peritoneal metastases from different primary sites in terms of safety, feasibility, response rate, and conversion to resectability. In this retrospective study, PIPAC was performed alone or in combination with systemic chemotherapy. Paclitaxel was used as a single agent, whereas docetaxel was used in combination with cisplatin-adriamycin or oxaliplatin-adriamycin. From December 2019 to December 2021, 47 patients underwent 82 PIPAC procedures (1 PIPAC in 55.3%, 2 in 29.7%, 3 in 14.8%). The most common primary sites were ovarian cancer (31.9%), gastric cancer (23.4%), and colorectal cancer (21.2%). Docetaxel-cisplatin-adriamycin was used in 33 (70.2%) patients, docetaxel-oxaliplatin-adriamycin in 12 (25.5%), and paclitaxel alone in 2 (4.2%) patients. Grade 1-2 complications were observed in 24 (51%) and grade 3-4 complications in 6 (12.7%) patients (8.5% of 82 PIPACs). 16/47 (34.0%) patients had a clinical response to PIPAC. The mean PCI was 25.9 ± 9.2 for the first PIPACs and 22.4 ± 9 for the subsequent PIPACs with an average reduction of 3.6 points [change in PCI ranged from - 14 to + 8]. The PRGS was 1/2 in 4/47 (8.5%) patients (19.0% patients with > 1 PIPAC). A reduction in ascites was observed in 35.4% presenting with ascites. Nine (19.1%) patients had conversion to operability leading to a subsequent cytoreductive surgery in 8 (17%) patients. PIPAC with docetaxel is feasible and safe. The role of PIPAC with both docetaxel and paclitaxel either alone or in combination with other drugs should be investigated in prospective studies.

Gastric Cancer With Peritoneal Metastasis-A Comprehensive Review of Current Intraperitoneal Treatment Modalities

The treatment of patients with peritoneal metastasis from gastric cancer continues to evolve. With various forms of intraperitoneal drug delivery available, it is now possible to reach the sites of peritoneal metastases, which were otherwise sub-optimally covered by systemic chemotherapy, owing to the blood peritoneal barrier. We conducted a narrative review based on an extensive literature research, highlighting the current available intraperitoneal treatment options, which resulted in improved survival in well-selected patients of peritoneally metastasized gastric cancer. Intraperitoneal chemotherapy showed promising results in four different treatment modalities: prophylactic, neoadjuvant, adjuvant, and palliative. It is now possible to choose the type of intraperitoneal treatment/s in combination with systemic treatment/s, depending on patients' general condition and peritoneal disease burden, thus providing individualized treatment to these patients. Randomized controlled trials for the different treatment modalities were mainly conducted in Asia and lack further validation in the other parts of the world. Most recent application tools, such as pressurized intraperitoneal aerosol chemotherapy, seem promising and need to pass the ongoing clinical trials.

Selection Criteria for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) Treatment in Patients with Peritoneal Metastases

Background: The standard treatment protocol for PIPAC consists of three procedures. Completion of treatment has been shown to be prognostic of improved survival. The aim of this study was to identify predictors for completion of treatment. Methods: Retrospective multicentric cohort study of patients with peritoneal metastases undergoing PIPAC in three PIPAC expert centers. Per protocol (PP) treatment was defined as patients receiving ≥3 PIPACs and was compared to patients receiving <3. Results: Overall, 183 patients had 517 PIPACs. The main reasons for stopping PIPAC were disease progression in 50% patients, bowel obstruction in 15%, patient’s refusal to pursue in 10%, conversion to cytoreductive surgery in 7%, and medical reasons in 8%. Overall, 95 patients (52%) had PP treatment. The PP median OS was 17 vs. 7 months, p = 0.001. PP patients had r ascites (410 ± 100 mL vs. 960 ± 188 mL, p = 0.001), no prior history of bowel obstruction (12% vs. 24%, p = 0.028), and more bimodal treatment (39% vs. 13%, p < 0.001). After multiple regression, bimodal treatment was found as an independent predictive factor for completing PP (OR = 4.202, 95%CI [1.813, 10.630], p < 0.001), along with prior bowel obstruction (OR = 0.389, 95%CI [0.153, 0.920], p = 0.037). Conclusion: The absence of ascites and prior bowel obstruction can help to select patients suitable for PIPAC. Best results seem to be achieved when PIPAC is combined with systemic chemotherapy.

Early postoperative outcomes of staging laparoscopy for peritoneal metastases with or without pressurized intra-peritoneal aerosol chemotherapy (PIPAC)

Background

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been introduced for palliative treatment of peritoneal surface malignancies (PSM) and is currently tested also in the neoadjuvant and prophylactic setting. The aim was therefore to compare safety and tolerance of staging laparoscopy with or without PIPAC.

Methods

This retrospective analysis compared consecutive patients undergoing staging laparoscopy alone for oesogastric cancer with patients having PIPAC for suspected PSM of various origins from January 2015 until January 2020. Safety was assessed by use of the Clavien classification for complications and CTCAE for capturing of adverse events. Pain and nausea were documented by use of a visual analogue scale (VAS: 0–10: maximal intensity).

Results

Overall, 25 PIPAC procedures were compared to 24 staging laparoscopies. PIPAC procedures took a median of 35 min (IQR: 25–67) longer. Four patients experienced at least one complication in either group (p = 0.741). No differences were noted for postoperative nausea (p = 0.961) and pain levels (p = 0.156). Median hospital stay was 2 (IQR: 1–3) for PIPAC and 1 (IQR: 1–2) for the laparoscopy group (p = 0.104).

Conclusions

The addition of PIPAC did not jeopardize safety and postoperative outcomes of staging laparoscopy alone. Further studies need to clarify its oncological benefits.

The Feasibility of Pressurised Intraperitoneal Aerosolised Virotherapy (PIPAV) to Administer Oncolytic Adenoviruses

BACKGROUND

The prognosis of patients with peritoneal metastases is poor. Treatment options are limited because systemically delivered chemotherapy is not usually effective in this type of disease. Pressurised intraperitoneal aerosolised chemotherapy (PIPAC) is a recently developed alternative technology for delivering intraperitoneal chemotherapy, potentially enhancing treatment efficacy. Here, we assess the feasibility of pressurised intraperitoneal aerosolised virotherapy (PIPAV) to deliver a different class of anticancer agents, oncolytic adenoviruses, in vitro and in vivo.

METHODS

Adenoviral vectors expressing reporter genes green fluorescence protein (Ad5.GFP) or firefly luciferase (Ad5.Luc) were subject to pressurised aerosolisation. The ability of the virus to survive PIPAV was assessed in vitro and in vivo by monitoring reporter gene activity. Wistar rats subjected to PIPAV were assessed for any adverse procedure related events.

RESULTS

In vitro transduction assays demonstrated that Ad5 retained viability following pressurised aerosolisation and could transduce permissive cells equally effectively as non-aerosolised control vector. PIPAV was well tolerated in rats, although minimal transduction was observed following intraperitoneal administration.

CONCLUSIONS

PIPAV appears viable and well tolerated, though in vivo efficacy requires further optimisation.

Consensus guidelines for pressurized intraperitoneal aerosol chemotherapy: Technical aspects and treatment protocols

BACKGROUND

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is increasingly used to treat patients with peritoneal cancer. A recent survey demonstrated considerable diversification of current practice of PIPAC raising issues of concern also regarding safety and efficacy. The study aim was to reach consensus on best practice of PIPAC treatment.

METHODS

Current practice was critically discussed during an expert meeting and the available evidence was scrutinized to elaborate a 33-item closed-ended questionnaire. All active PIPAC centers were then invited to participate in an online two-round Delphi process with 3 reminders at least. Consensus was defined a priori as >70% agreement for a minimal response rate of 70%.

RESULTS

Forty-nine out of 57 invited PIPAC centers participated in Delphi 1 and 2 (86%). Overall, there was agreement for 21/33 items. Consensus was reached for important aspects like advanced OR ventilation system (91.8%), remote monitoring (95.9%), use of the PRGS (85.7%) and use of a safety checklist (98%). The drug regimens oxaliplatin (87.8%) and cisplatin/doxorubicin (81.6%) were both confirmed by the expert panel. Important controversies included number and location of Biopsies during repeated PIPAC and the combination of PIPAC with additional surgical procedures.

CONCLUSION

This consensus statement aims to allow for safe and efficacious PIPAC treatment and to facilitate multi-center analyses of the results. Additional preclinical and clinical studies are needed to resolve the remaining controversies.

Histological regression of gastrointestinal peritoneal metastases after systemic chemotherapy

Objectives

Peritoneal metastases (PM) are relatively resistant to systemic chemotherapy, and data on histological response to therapy is rare. The aim of this study was to quantify the treatment response of PM after systemic chemotherapy.

Methods

Retrospective monocentric cohort study of 47 consecutive patients with PM from gastrointestinal origin undergoing surgery (cytoreduction: CRS + Hyperthermic IntraPEritoneal Chemotherapy [HIPEC] or Pressurized IntraPeritoneal Aerosol Chemotherapy [PIPAC]) after prior systemic chemotherapy from 1.2015 to 3.2019. Tumor response was assessed using the 4-scale Peritoneal Regression Grading System (PRGS) (4: vital tumor to 1: complete response).

Results

Patients had a median of 2 (range: 1-7) lines and 10 (3-39) cycles of prior systemic chemotherapy. A median of four biopsies (range: 3-8) was taken with a total of 196 analyzed specimens. Twenty-four biopsies (12%) showed no histological regression (PRGS4), while PRGS 3, two and one were diagnosed in 37 (19%), 39 (20%), and 69 (49%) specimens, respectively. A significant heterogeneity was found between peritoneal biopsies in 51% patients. PRGS correlated strongly with peritoneal spread (PCI, p<0.0001), and was improved in patients with more than nine cycles of systemic chemotherapy (p=0.04). Median survival was higher in patients with PRGS < 1.8 (Quartiles one and 2) than higher (Q3 and Q4), but the difference did not reach significance in this small cohort.

Conclusions

PRGS is an objective too to describe histological response of PM of GI origin after systemic chemotherapy. This response differs significantly between patients, allowing to distinguish between chemosensitive and chemoresistant tumors.

The ISSPP PIPAC database: design, process, access, and first interim analysis

Objectives

Several trials have documented the favorable safety profile, and promising clinical results of pressurized intraperitoneal aerosol chemotherapy (PIPAC) directed treatment in different types of peritoneal malignancies. However, until the results of randomized trials are available, the quality of documentation and acceptance by the users may be improved through a worldwide registry. The International Society for the Study of Pleura and Peritoneum (www.ISSPP.org) facilitated this process by creating a dedicated focus group and providing the funding needed for the creation and implementation of an international database. This article describes the design and the journey of establishing this international database and the first, preliminary results from the ISSPP PIPAC online database.

Methods

In 2019 the ISSPP PIPAC Registry Group started to create a database with a minimal dataset relevant to many diseases and applicable in different framework conditions. The task was divided into three phases including design, testing, implementation, protocol, handbook, legal requirements, as well as registry rules and bylaws for the registry group.

Results

The ISSPP PIPAC online database has six key elements (patient, consent, treatment, complications, response evaluation and follow-up). Following design, testing and implementation the database was successfully launched in June 2020. Ten institutions reported on 459 PIPAC procedures in 181 patients during the first 6 months, and the recorded data were comparable to the present literature.

Conclusions

A new international multicenter PIPAC database has been developed, tested and implemented under the auspices of ISSPP. The database is accessible through the ISSPP website (www.ISSPP.org), and PIPAC institutions worldwide are highly encouraged to participate.

Evaluation of the environmental contamination and exposure risk in medical/non-medical staff after oxaliplatin-based pressurized intraperitoneal aerosol chemotherapy

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a technique to directly deliver chemotherapeutic drugs in the abdomen for the treatment of peritoneal metastases. Pressurization improves the treatment efficacy but increases the risk of exposure for the medical/non-medical staff who can be exposed by dermal or ocular contact, or inhalation of aerosols containing the cytotoxic drugs. The aim of this study was to evaluate the risk of exposure for the medical/non-medical staff (nurses, surgeons, anaesthesiologists and cleaning personnel; n = 13) during PIPAC with oxaliplatin performed according to the protocol recommended in France. Blood samples were collected 1 h before and immediately after PIPAC, and urine samples 1 h before, and then 3 h and the morning after PIPAC. In the control, non-exposed group (n = 7), only one urine and blood sample were collected. Surface contamination in the operating room was assessed in water- and Surfanios-impregnated wipe samples. The total elemental platinum in each sample was quantified by inductively coupled plasma mass spectrometry, using a method adapted to quantify trace amounts (ng.L^-1) in very low volumes (100 μl). No surface contamination was detected. Although 25% of urine samples in the exposed group contained platinum, no statistical difference was observed in urine and plasma samples collected before and after PIPAC and with the control group samples. These findings suggest that the French PIPAC protocol does not increase the risk of exposure to platinum in all staff categories involved. This protocol could be considered in future occupational policies and consensus statements. Trial registration: NCT04014426.

Exploring High Pressure Nebulization of Pluronic F127 Hydrogels for Intraperitoneal Drug Delivery

Peritoneal metastasis is an advanced cancer type which can be treated with pressurized intraperitoneal aerosol chemotherapy (PIPAC). Here, chemotherapeutics are nebulized under high pressure in the intraperitoneal (IP) cavity to obtain a better biodistribution and tumor penetration. To prevent the fast leakage of chemotherapeutics from the IP cavity, however, nebulization of controlled release formulations is of interest. In this study, the potential of the thermosensitive hydrogel Pluronic F127 to be applied by high pressure nebulization is evaluated. Therefore, aerosol formation is experimentally examined by laser diffraction and theoretically simulated by computational fluid dynamics (CFD) modelling. Furthermore, Pluronic F127 hydrogels are subjected to rheological characterization after which the release of fluorescent model nanoparticles from the hydrogels is determined. A delicate equilibrium is observed between controlled release properties and suitability for aerosolization, where denser hydrogels (20% and 25% w/v Pluronic F127) are able to sustain nanoparticle release up to 30 hours, but cannot effectively be nebulized and vice versa. This is demonstrated by a growing aerosol droplet size and exponentially decreasing aerosol cone angle when Pluronic F127 concentration and viscosity increase. Novel nozzle designs or alternative controlled release formulations could move intraperitoneal drug delivery by high pressure nebulization forward.

Radiologist Checklist for Selecting Patients to Undergo PIPAC (Pressurized IntraPeritoneal Aerosol Chemotherapy)

Peritoneal carcinomatosis frequently occurs in advanced gastrointestinal and gynecological cancers. As factors such as poor drug uptake and distribution cause chemotherapy to be less effective, alternative therapies have been explored. Introduced in 2013, PIPAC (pressurized intraperitoneal aerosol chemotherapy) uses aerosolized chemotherapeutics sprayed into the patient’s peritoneal cavity using a laparoscopic approach. Despite the literature showing encouraging data regarding the tolerability and efficacy of PIPAC, there is a lack of articles on the role that imaging plays in selecting patients suitable for PIPAC. The aim of this study is to combine literature-based evidence and clinical experience to provide information able to support training radiologists, as well as experienced radiologists interested in innovative therapies.

Study Protocol: Phase I Dose Escalation Study of Oxaliplatin, Cisplatin and Doxorubicin Applied as PIPAC in Patients with Peritoneal Metastases

Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) is a novel laparoscopic intraperitoneal chemotherapy approach offered in selected patients affected by non-resectable peritoneal carcinomatosis. Drugs doses currently established for nebulization are very low: oxaliplatin (OXA) 120 mg/sm, cisplatin (CDDP) 10.5 mg/sm and doxorubicin (DXR) 2.1 mg/sm. A model-based approach for dose-escalation design in a single PIPAC procedure and subsequent dose escalation steps is planned. The starting dose of oxaliplatin is 100 mg/sm with a maximum estimated dose of 300 mg/sm; an escalation with overdose and under-dose control (for probability of toxicity less than 16% in case of under-dosing and probability of toxicity greater than 33% in case of overdosing) will be further applied. Cisplatin is used in association with doxorubicin: A two-dimensional dose-finding design is applied on the basis of the estimated dose limiting toxicity (DLT) at all combinations. The starting doses are 15 mg/sm for cisplatin and 3 mg/sm for doxorubicin. Safety is assessed according to Common Terminology Criteria for Adverse Events (CTCAE version 4.03). Secondary endpoints include radiological response according to Response Evaluation Criteria in Solid Tumor (version 1.1) and pharmacokinetic analyses. This phase I study can provide the scientific basis to maximize the optimal dose of cisplatin, doxorubicin and oxaliplatin applied as PIPAC.

Pressurized intra-peritoneal aerosol chemotherapy (PIPAC): increased intraperitoneal pressure does not affect distribution patterns but leads to deeper penetration depth of doxorubicin in a sheep model

BACKGROUND

Pressurized Intra-Peritoneal Aerosol Chemotherapy (PIPAC) is an innovative treatment against peritoneal carcinomatosis. Doxorubicin is a common intra-venous chemotherapy used for peritoneal carcinomatosis and for PIPAC. This study evaluated the impact of increased PIPAC intraperitoneal pressure on the distribution and cell penetration of doxorubicin in a sheep model.

METHODS

Doxorubicin was aerosolized using PIPAC into the peritoneal cavity of 6 ewes (pre-alpes breed): N = 3 with 12 mmHg intraperitoneal pressure ("group 12") and N = 3 with 20 mmHg ("group 20"). Samples from peritoneum (N = 6), ovarian (N = 1), omentum (N = 1) and caecum (N = 1) were collected for each ewe. The number of doxorubicin positive cells was determined using the ratio between doxorubicine fluorescence-positive cell nuclei (DOXO+) over total number of DAPI positive cell nuclei (DAPI+). Penetration depth (μm) was defined as the distance between the luminal surface and the location of the deepest DOXO+ nuclei over the total number of cell nuclei that were stained with DAPI. Penetration depth (μm) was defined as the distance between the luminal surface and the location of the deepest DOXO+ nuclei.

RESULTS

DOXO+ nuclei were identified in 87% of samples. All omental samples, directly localized in front of the nebulizer head, had 100% DOXO+ nuclei whereas very few nuclei were DOXO+ for caecum. Distribution patterns were not different between the two groups but penetration depth in ovary and caecum samples was significantly deeper in group 20.

CONCLUSIONS

This study showed that applying a higher intra-peritoneal pressure during PIPAC treatment leads to a deeper penetration of doxorubicin in ovarian and caecum but does not affect distribution patterns.

A Phase I Dose Escalation Study of Oxaliplatin, Cisplatin and Doxorubicin Applied as PIPAC in Patients with Peritoneal Carcinomatosis

Simple Summary

This study is one of the very few phase I trials on intraperitoneal chemotherapy applied as PIPAC. Cisplatin and doxorubicin may be safely used as PIPAC at a dose of 30 mg/m² and 6 mg/m², respectively; oxaliplatin can be used at an intraperitoneal dose of 135 mg/m². No serious adverse event was reported. The dosages achieved to date are the highest ever used in PIPAC. The results of these investigations should be the starting point for further clinical phase II trials regarding repeated PIPAC, possibly associated with systemic chemotherapy.

Abstract

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an innovative laparoscopic intraperitoneal chemotherapy approach with the advantage of a deeper tissue penetration. Thus far, oxaliplatin has been administered at an arbitrary dose of 92 mg/m², cisplatin at 7.5 mg/m² and doxorubicin 1.5 mg/m². This is a model-based approach phase I dose escalation study with the aim of identifying the maximum tolerable dose of the three different drugs. The starting dose of oxaliplatin was 100 mg/m²; cisplatin was used in association with doxorubicin: 15 mg/m² and 3 mg/m² were the respective starting doses. Safety was assessed according to Common Terminology Criteria for Adverse Events (CTCAE version 4.03). Thirteen patients were submitted to one PIPAC procedure. Seven patients were treated with cisplatin and doxorubicin and 6 patients with oxaliplatin; no dose limiting toxicities and major side effects were found. Common adverse events included postoperative abdominal pain and nausea. The maximum tolerable dose was not reached. The highest dose treated cohort (oxaliplatin 135 mg/m²; cisplatin 30 mg/m² and doxorubicin 6 mg/m²) tolerated PIPAC well. Serological analyses revealed no trace of doxorubicin at any dose level. Serum levels of cis- and oxaliplatin reached a peak at 60–120 min after PIPAC and were still measurable in the circulation 24 h after the procedure. Cisplatin and doxorubicin may be safely used as PIPAC at a dose of 30 mg/m² and 6 mg/m², respectively; oxaliplatin can be used at an intraperitoneal dose of 135 mg/m². The dosages achieved to date are the highest ever used in PIPAC.

Experimental evaluation of icodextrin delivery as pressurized aerosol (PIPAC): Antiadhesive and cytotoxic effects

BACKGROUND

Icodextrin (IDX) is an antiadhesive polymer that can be used as a carrier solution for intraperitoneal (IP) delivery of chemotherapeutic drugs.

METHODS

We investigated the suitability of IDX solution as a carrier of Cisplatin and Doxorubicin for delivery as pressurized intraperitoneal aerosol chemotherapy (PIPAC). We examined the sprayability of IDX, the aerosol characteristics, the stability of the molecule after aerosolization, the effects of IDX on the adhesion of MKN45 human gastric cancer cells, the synergistic effect of aerosolized IDX with Cisplatin and Doxorubicin, and the chemical stability of IDX, Cisplatin, and Doxorubicin in combination.

RESULTS

Delivery of IDX as PIPAC is feasible with no particular restrictions. The median droplet size of 35.7 μm did not change at increasing concentrations. IDX withstood the shear forces applied by the nebulizer and remained stable after aerosolization (ANOVA, p = 0.97). IDX did not impair the cytotoxic effects of Cisplatin and Doxorubicin (ns). IDX had a significant antiadhesive impact alone (p < 0.03) and in combination with Cisplatin and Doxorubicin (p < 0.02). IDX as a carrier for Cisplatin and Doxorubicin remained stable at 4 °C for three months and did not cause degradation of those two substances.

CONCLUSION

The proposed combination takes advantage of the antiadhesive properties of IDX, the cytotoxic effect of Cisplatin and Doxorubicin, and an advanced drug delivery system.

Enhanced intraperitoneal delivery of charged, aerosolized curcumin nanoparticles by electrostatic precipitation

Aims: To investigate the potential of curcumin-loaded polylactic-co-glycolic acid nanoparticles (CUR-PLGA-NPs), alone and with electrostatic precipitation, for improving tissue uptake during pressurized intraperitoneal aerosol chemotherapy (PIPAC). Methods: Positively and negatively charged CUR-PLGA-NPs were delivered as PIPAC into inverted bovine urinary bladders ex vivo. The experiment was repeated with the additional use of electrostatic precipitation pressurized intraperitoneal aerosol chemotherapy (electrostatic PIPAC). Results: Positively charged CUR-PLGA-NPs increased depth of tissue penetration by 81.5% and tissue concentration by 80%. Electrostatic precipitation further improved the uptake of positively charged CUR-PLGA-NPs by 41.8%. Conclusion: The combination of positive charge and electrostatic precipitation have significant potential to improve tissue uptake of nanoparticles during intraperitoneal chemotherapy.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) for rare gynecologic indications: peritoneal metastases from breast and endometrial cancer

BACKGROUND

Peritoneal metastasis (PM) in patients with breast (BC) and endometrial cancer (EC) is rare and treatment options are limited. Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) has demonstrated efficacy against PM from various cancers, but its efficacy in BC/EC patients is unknown.

METHODS

Retrospective cohort study of patients with PM from BC/EC undergoing PIPAC with doxorubicin 1.5 mg/m² and cisplatin 7.5 mg/m². Data were collected within an international prospective PIPAC registry. Study outcomes were microscopic tumor regression grade (TRG), survival, adverse events (CTCAE), and quality of life (QoL).

RESULTS

150 PIPAC procedures in 44 patients (BC/EC = 28/16; mean age 58.8 ± 10.1 and 63.2 ± 10.1 years, respectively) were analyzed. The mean number of PIPACs per patient was 3 (range 0-9) and 3.5 (range 0-10), respectively. Primary/secondary non-access occurred in 4/3 of 150 (5%) procedures. PIPAC induced objective tumor regression as demonstrated by repetitive PM biopsies in 73% (32/44) of patients. Peri- and postoperative CTCAE grade 3 and 4 complications were observed in 12/150 (8%) of procedures. No grade 5 event was observed. After a median follow up of 5.7 (IQR 2.7-13.0) months, overall median survival was 19.6 (95% CI: 7.8-31.5) months (from first PIPAC). QoL indicators (general health, nausea, fatigue, constipation, pain, dyspnea, social, cognitive, emotional, and physical functioning) all improved or were maintained throughout PIPAC treatments.

CONCLUSIONS

Repetitive intraperitoneal chemotherapy with PIPAC is feasible and safe in patients with PM from BC and EC. PIPAC induces significant histological regression of PM while maintaining QoL.

A phase I dose-escalation study of oxaliplatin delivered via a laparoscopic approach using pressurised intraperitoneal aerosol chemotherapy for advanced peritoneal metastases of gastrointestinal tract cancers

OBJECTIVE

The objectives were to define the maximum tolerated dose (MTD), safety profile and pharmacokinetics (PKs) of intraperitoneal oxaliplatin delivered by pressurised intraperitoneal aerosol chemotherapy (PIPAC) in patients with advanced peritoneal carcinomatosis from gastrointestinal tract cancers.

METHODS

PIPAC was applied every 4-6 weeks, for 5 cycles, in a phase I dose-escalation study using a 3 + 3 design. The first dose level was 90 mg/m² with planned increases of 50 mg/m² per level. Platinum concentration was measured in plasma, tissues and intraperitoneal fluid samples. The trial was registered at ClinicalTrials.gov (NCT03294252).

RESULTS

Ten patients with 33 PIPAC sessions were included. No dose limiting toxicity (DLT) occurred at 90 mg/m² and two at 140 mg/m². The MTD was therefore set at 90 mg/m². Overall treatment included a median number of three PIPAC sessions (range: 1-5) and secondary complete cytoreductive surgery for two patients. Overall safety showed 67 grade I-II and 11 grade III-IV toxicities, usually haematologic, digestive (nausea/vomiting, abdominal pain), and fatigue. Oxaliplatin concentrations were three- to four-fold higher in tissue in contact with aerosol than in muscle without contact. At 140 mg/m², the plasma oxaliplatin concentration was high with Cmax and area under the curve (AUC)_0-48h of 1035 μg/l and 9028 μg h/L, respectively.

CONCLUSIONS

The MTD of oxaliplatin during PIPAC is 90 mg/m². PK data demonstrate a high tumour concentration and a significant systemic absorption.

PIPAC versus HIPEC: cisplatin spatial distribution and diffusion in a swine model

Purpose: Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a novel approach for delivering intraperitoneal chemotherapy and offers perspective in the treatment of peritoneal carcinomatosis. Concept is based on a 12 mmHg capnoperitoneum loaded with drug changed in microdoplets. It was postulated to guarantee a more homogeneous drug distribution and tissular uptake than hyperthermic intraperitoneal chemotherapy (HIPEC). The aim of this study was to compare cisplatin peritoneal distribution and pharmacokinetic between HIPEC and PIPAC procedures in a healthy swine model.Methods: Two groups of eight pigs underwent either HIPEC with cisplatin (70 mg/m²) at 43 °C for 60 min, or PIPAC with cisplatin (7.5 mg/m²) for 30 min. Postoperatively, peritoneal areas were biopsied allowing peritoneal cavity cartography. Tissular and plasmatic cisplatin concentrations were analyzed.Results: Cisplatin distribution was heterogeneous in both the groups with higher concentrations obtained closed to the delivery sites. Median total platinum peritoneal concentration by pig was higher in the HIPEC group than in the PIPAC group (18.0 μg/g versus 4.3 μg/g, p < .001) but the yield was 2.2 times better with PIPAC. Platinum concentrations were higher in the HIPEC group in all stations. At each time-point, cisplatin plasmatic concentrations were higher in the HIPEC group (p < .001) but beneath the toxicity threshold.Conclusions: With doses used in clinical practice, HIPEC guaranteed a higher cisplatin peritoneal uptake than PIPAC in this swine model. Spatial drug distribution was heterogeneous with both technics, with hotspots closed to the drug delivery sites. Nevertheless, considering the dose ratio, IP drug uptake yield was better with PIPAC.

Prognostic impact of combined progression index based on peritoneal grading regression score and peritoneal cytology in peritoneal metastasis

AIMS

The peritoneal regression grading score (PRGS) and peritoneal cytology (PC) assess response to chemotherapy in peritoneal metastasis (PM) in a setting of palliative treatment by pressurized intraperitoneal aerosol chemotherapy (PIPAC). Progression has been defined as an increase of PRGS between first and third PIPAC procedures (iPRGS). iPRGSand positive peritoneal cytology were not associated with prognostic impact. These results may be explained by a lack of statistical power. Also, it is not known whether the mean or the highest PRGS among taken peritoneal biopsies bears the highest clinical value. We therefore conducted the largest prospective study to investigate the prognostic impact of PGRS, PC, and their combination, designated as combined progression index (CPI).

METHODS AND RESULTS

Patients with PM who underwent >3 PIPAC (n = 112) between December 2016 and February 2019 were prospectively included. A significant difference in OS and PFS according to CPI (used highest value of PRGS) was found (OS: CPI-, 83.3, 95% CI [49.8; NA] vs. CPI+, 48.1, 95% CI [38.5; 66.4] months; and PFS (respectively, 59.7, 95% CI [43.0; 96.0] vs. 33.7, 95% CI [30.4; 44.2] months). PRGS or PC had no independent prognostic impact. CPI+ was an independent predictor of worse prognosis, in OS (HR = 5.24, 95% CI [2.07; 13.26]), and PFS (HR = 4.41, 95% CI [1.40; 13.88]).

CONCLUSIONS

The CPI based on highest PRGS and PC was found to be independently associated with a worse prognosis for OS and for PFS in the setting of peritoneal metastasis. These results indicate that it should be of interest to systematically take peritoneal fluid for cytological examination and to implement the CPI in the therapeutic decision-making process in the context of PIPAC.

Systematic review of patient reported outcomes (PROs) and quality of life measures after pressurized intraperitoneal aerosol chemotherapy (PIPAC)

Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC) constitutes a recently described surgical technique to administer chemotherapy directly to the peritoneum, under pressure, for patients with peritoneal metastasis (PM). The purpose of an oncological treatment is to improve survival but without altering the patient's quality of life. The aim of this review was to evaluate patient-reported outcomes (PRO) after PIPAC for patients with PM. This systematic review was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Between January 1, 2013, and January 1, 2020, studies were selected according to the following criteria: "pressurized intraperitoneal aerosol chemotherapy" OR "PIPAC" AND "patient-reported outcomes" OR "PRO" OR "Quality of life". In this review, 959 PIPAC and five PITAC (Pressurized IntraThoracic Aerosol Chemotherapy) were performed in 425 patients. We highlight the prominent application of generic EORTC QLQ-C30 followed by SF-36 in this review. The PROs according to the EORTC-QLQ-C30 global health score and based on symptom and function scores were stable across most studies. Moreover, PIPAC has improved the PRO of altered patients in two studies. Among 425 patients, the mortality rate was 0.7% and adverse events of Common Terminology Criteria of Adverse Events grade 3 and grade 4 were 9.6% and 1.6%, respectively. We synthesised current research on PROs among patients with PM. This review increases our understanding of the PIPAC strategy from the patient perspective. The implementation of PROs can be complex but will be essential in delivering quality care.

Initial Single-center Experience of PIPAC in Patients With Unresectable Peritoneal Metastasis

INTRODUCTION

Peritoneal carcinomatosis remains a condition with poor prognosis and limited therapeutic options. Pressurized Intrapertioneal Aerosol Chemotherapy (PIPAC) has been developed as a new tool for delivering intraperitoneal chemotherapy with low morbidity. The aim of this study was to evaluate the initial experience of PIPAC in patients with peritoneal carcinomatosis at our hospital.

METHODS

A prospective study between January 2019 and February 2020 was carried at a tertiary public hospital. Primary tumor, ascites volume, PCI, chemotherapy regimen, operative time, morbidity, length of hospital stay and mortality were recorded for analysis.

RESULTS

We analyzed 9 PIPAC procedures performed in 5patients. Median PCI was 27.6 (24-35). Median surgical time was 93minutes (70-125). Only one adverse event occurred out of 9 procedures (Clavien-DindoII). Median length of hospital stay was 2days (1-4). Mortality was 0%.

CONCLUSION

PIPAC seems to be a feasible and safe procedure to treat peritoneal carcinomatosis, with low morbidity and short hospital stay.

Restricted access to innovative surgical technique related to a specific training, is it ethical? Example of the PIPAC procedure. A systematic review and an experts survey

OBJECTIVE

Using the example of Pressurized Intra Peritoneal Aerosol Chemotherapy (PIPAC), we analyse the development model of this procedure and provide an ethical analysis of the involvement of the industry in a new development.

SUMMARY BACKGROUND DATA

In the case of breakthrough innovation, medical training is essential for safe use of the new procedure. In some cases, pharmaceutical companies decide to organise this training. But when it becomes the only training opportunity to use the device, scientists and clinicians could be exposed to a conflict of interest?

METHODS

We performed a literature review of PIPAC publications using the STROBE criteria. Then, we conducted interviews with an expert panel to analyse the ethical impact of involvement of the industry in the development of the PIPAC procedure.

RESULTS

The number of publications has increased every year since the first publication in Germany, where the technology was developed in 2013. The scientific production was of good quality, with a mean STROBE score of 18.2 ± 2.4 out of 22 points. Ten of the 33 included studies declared a conflict of interest. From the interviews, the main axe concerning the implication of the industry was the training model. The company had decided that only trained and approval surgeon could perform the PIPAC procedure. All four interviewed practitioners agreed that it was initially a good way to implement the procedure safely, but later they felt uncomfortable about the control and validation by the industry.

CONCLUSION

Based on the growing number of published papers from a growing number of international centres, the controlled training model is not limiting. However, the different levels of conflict of interest complicate transparency, and we postulated that this development model is limited to the beginning of the procedure diffusion. CLINICALTRIAL.

GOV REGISTRATION

NCT04341337.

Electrostatic Intraperitoneal Aerosol Delivery of Nanoparticles: Proof of Concept and Preclinical Validation

There is an increasing interest in intraperitoneal delivery of chemotherapy as an aerosol in patients with peritoneal metastasis. The currently used technology is hampered by inhomogenous drug delivery throughout the peritoneal cavity because of gravity, drag, and inertial impaction. Addition of an electrical force to aerosol particles, exerted by an electrostatic field, can improve spatial aerosol homogeneity and enhance tissue penetration. A computational fluid dynamics model shows that electrostatic precipitation (EP) results in a significantly improved aerosol distribution. Fluorescent nanoparticles (NPs) remain stable after nebulization in vitro, while EP significantly improves spatial homogeneity of NP distribution. Next, pressurized intraperitoneal chemotherapy with and without EP using NP albumin bound paclitaxel (Nab-PTX) in a novel rat model is examined. EP does not worsen the effects of CO₂ insufflation and intraperitoneal Nab-PTX on mesothelial structural integrity or the severity of peritoneal inflammation. Importantly, EP significantly enhances tissue penetration of Nab-PTX in the anatomical regions not facing the nozzle of the nebulizer. Also, the addition of EP leads to more homogenous peritoneal tissue concentrations of Nab-PTX, in parallel with higher plasma concentrations. In conclusion, EP enhances spatial homogeneity and tissue uptake after intraperitoneal nebulization of anticancer NPs.