Next-generation sequencing and histological response assessment in peritoneal metastasis from pancreatic cancer treated with PIPAC

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.

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.

RNA expression profiling of peritoneal metastasis from pancreatic cancer treated with Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC)

Objectives

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an experimental treatment option in peritoneal metastasis from pancreatic cancer (PM-PC). Aims were to examine mRNA profile of fibrosis due to response after systemic chemotherapy and PIPAC (Regression) compared to treatment-naïve PM-PC and chronic cholecystitis-related peritoneal fibrosis (Controls).

Methods

Peritoneal biopsies (PBs) from PM-PC patients who had undergone systemic chemotherapy and PIPAC were evaluated with Peritoneal Regression Grading Score (PRGS). We extracted RNA from PBs with Regression (PRGS 1, n=11), treatment-naïve PM-PC (n=10), and Controls (n=10). Profiling of 800 mRNAs was performed (NanoString nCounter, PanCancer Immuno-Oncology 360 (IO-360) and 30 additional stroma-related mRNAs).

Results

Regression vs. PM-PC identified six up-regulated and 197 down-regulated mRNAs (FDR≤0.05), linked to TNF-α signaling via NF-kB, G2M checkpoint, epithelial-mesenchymal transition, estrogen response, and coagulation. Regression vs. Controls identified 43 significantly up-regulated mRNAs, linked to interferon-α response, and down-regulation of 99 mRNAs, linked to TNF-α signaling via NF-kB, inflammatory response, epithelial-mesenchymal transition, KRAS signaling, and hypoxia (FDR≤0.05).

Conclusions

In regressive fibrosis of PM-PC after systemic chemotherapy and PIPAC (Regression), downregulation of mRNAs related to key tumor biological pathways was identified. Regression also showed transcriptional differences from unspecific, benign fibrosis (Controls). Future studies should explore whether mRNA profiling of PBs with PM from PC or other primaries holds prognostic or predictive value.

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.

Peritoneal regression grading score (PRGS): first evidence for independent predictive and prognostic significance

Objectives

The peritoneal regression grading score (PRGS) is a four-tied pathologic score measuring tumor regression in biopsies from patients with peritoneal metastasis (PM) receiving chemotherapy.

Methods

This retrospective analysis of a prospective registry (NCT03210298) analyses 97 patients with isolated PM under palliative chemotherapy. We examined the predictive value of the initial PRGS for overall survival (OS) and the prognostic value of PRGS in repeated peritoneal biopsies.

Results

The 36 (37.1 %) patients with an initial mean PRGS≤2 had a longer median OS (12.1 months, CI 95 % 7.8-16.4) vs. 8.0 months (CI 95 % 5.1-10.8 months) in 61 (62.9 %) patients with PRGS≥3 (p=0.02) After stratification, the initial PRGS was an independent predictor of OS (Cox-regression, p<0.05). Out of 62 patients receiving≥two chemotherapy cycles, 42 (67.7 %) had a histological response (defined as a lower or stable mean PRGS in successive therapy cycles), and 20 (32.3 %) progressed (defined as an increasing mean PRGS). PRGS response was associated with a longer median OS (14.6 months, CI 5-95 % 6.0-23.2) vs. 6.9 (CI 5-95 % 0.0-15.9) months. PRGS response was prognostic in the univariate analysis (p=0.017). Thus, PRGS had both a predictive and prognostic significance in patients with isolated PM receiving palliative chemotherapy in this patient cohort.

Conclusions

This is the first evidence for the independent predictive and prognostic significance of PRGS in PM. These encouraging results need validation in an adequately powered, prospective study.

10 Years of Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC): A Systematic Review and Meta-Analysis

BACKGROUND

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a novel intraperitoneal drug delivery method of low-dose chemotherapy as a pressurized aerosol in patients affected by peritoneal cancer of primary or secondary origin. We performed a systematic review and meta-analysis with the aim of assessing the feasibility, safety, and efficacy of PIPAC.

METHODS

A systematic literature search was performed using Medline and Web of Science databases from 1 January 2011, to inception, to 31 December 2021. Data were independently extracted by two authors. The Newcastle-Ottawa Scale was used to assess the quality and risk of bias of studies. Meta-analysis was performed for pathological response, radiological response, PCI variation along treatment, and for patients undergoing three or more PIPAC. Pooled analyses were performed using the Freeman-Tukey double arcsine transformation, and 95% CIs were calculated using Clopper-Pearson exact CIs in all instances.

RESULTS

A total of 414 papers on PIPAC were identified, and 53 studies considering 4719 PIPAC procedure in 1990 patients were included for analysis. The non-access rate or inability to perform PIPAC pooled rate was 4% of the procedures performed. The overall proportion of patients who completed 3 or more cycles of PIPAC was 39%. Severe toxicities considering CTCAE 3-4 were 4% (0% to 38.5%). In total, 50 studies evaluated deaths within the first 30 postoperative days. In the included 1936 patients were registered 26 deaths (1.3%). The pooled analysis of all the studies reporting a pathological response was 68% (95% CI 0.61-0.73), with an acceptable heterogeneity (I² 28.41%, p = 0.09). In total, 10 papers reported data regarding the radiological response, with high heterogeneity and a weighted means of 15% (0% to 77.8%). PCI variation along PIPAC cycles were reported in 14 studies. PCI diminished, increased, or remained stable in eight, one and five studies, respectively, with high heterogeneity at pooled analysis. Regarding survival, there was high heterogeneity. The 12-month estimated survival from first PIPAC for colorectal cancer, gastric cancer, gynecological cancer and hepatobiliary/pancreatic cancer were, respectively, 53%, 25%, 59% and 37%.

CONCLUSIONS

PIPAC may be a useful treatment option for selected patients with PM, with acceptable grade 3 and 4 toxicity and promising survival benefit. Meta-analysis showed high heterogeneity of data among up-to-date available studies. In a subset analysis per primary tumor origin, pathological tumor regression was documented in 68% of the studies with acceptable heterogeneity. Pathological regression seems, therefore, a reliable outcome for PIPAC activity and a potential surrogate endpoint of treatment response. We recommend uniform selection criteria for patients entering a PIPAC program and highlight the urgent need to standardize items for PIPAC reports and datasets.

Response Evaluation in Patients with Peritoneal Metastasis Treated with Pressurized IntraPeritoneal Aerosol Chemotherapy (PIPAC)

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) directed therapy emerged as a treatment of peritoneal metastasis (PM) a decade ago. The response assessment of PIPAC is not uniform. This narrative review describes non-invasive and invasive methods for response evaluation of PIPAC and summarizes their current status. PubMed and clinicaltrials.gov were searched for eligible publications, and data were reported on an intention-to-treat basis. The peritoneal regression grading score (PRGS) showed a response in 18-58% of patients after two PIPACs. Five studies showed a cytological response in ascites or peritoneal lavage fluid in 6-15% of the patients. The proportion of patients with malignant cytology decreased between the first and third PIPAC. A computed tomography showed stable or regressive disease following PIPAC in 15-78% of patients. The peritoneal cancer index was mainly used as a demographic variable, but prospective studies reported a response to treatment in 57-72% of patients. The role of serum biomarkers of cancer or inflammation in the selection of candidates for and responders to PIPAC is not fully evaluated. In conclusion, response evaluation after PIPAC in patients with PM remains difficult, but PRGS seems to be the most promising response evaluation modality.

A single-center randomized controlled study of intraperitoneal hyperthermic chemoperfusion in combination of recombinant human tumor necrosis factor (TNF) in treatment of malignant ascites caused by advanced abdominal cancers

INTRODUCTION

Malignant peritoneal effusion is a common complication of advanced malignancies, which has a poor prognosis for patients. Hyperthermic intraperitoneal chemotherapy (HIPEC) has been widely used in the treatment of advanced gynecological tumors, especially ovarian cancer (OC). Relative studies have indicated that HIPEC allows for direct exposure of tumor cells to high peritoneal concentrations of cytotoxic drugs without increasing systemic toxicity compared with intravenous treatment. Recombinant human tumor necrosis factor for injection (rmhTNF-NC) is a safely tolerated immunotherapeutic drug that has becoming a mainstay of treatment for malignant effusions. Currently, a prospective study is required to determining the efficacy of rmhTNF-NC plus cisplatin for the treatment of malignant peritoneal effusion for OC.

METHODS

Design and setting: This is a single-center, open trial will be performed in Zhongshan Affiliated Hospital, Guangzhou University of Chinese Medicine.

PARTICIPANTS

Eligible patients will be those with advanced gynecologic cancers and who would be suitable for HIPEC.

INTERVENTION AND CONTROL

HIPEC with cisplatin and intraperitoneal perfusion with rmhTNF-NC.

COINTERVENTIONS

Further chemotherapy will be offered to patients as per current practice.OutcomesPilot study: Patients and clinicians' acceptability of the trial to assist in optimization of recruitment.Primary outcome: One-year overall survival (OS).Secondary outcomes: Progression-free survival (PFS), adverse events.Follow-up: One-year follow-up for OS.Sample size: Twenty patients to demonstrate therapeutic effect of peritoneal effusion caused by OC.

DISCUSSION

This trial will determine the effectiveness of HIPEC with cisplatin and intraperitoneal perfusion with rmhTNF-NC for advanced gynecologic cancers, and guide the optimal treatment for these patients.

Intraperitoneal chemotherapy in the management of pancreatic adenocarcinoma: A systematic review and meta-analysis

BACKGROUND

Pancreatic cancer represents one of the leading causes of cancer-related death worldwide. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC), normothermic intraperitoneal chemotherapy (NIPEC), and pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been proven with curative intent mainly for other tumors and there is a lack of consensus regarding possible benefits also in pancreatic cancer. The present systematic review and meta-analysis aim to provide an up-to-date overview of the effectiveness and safety of intraperitoneal treatments in the management of pancreatic cancer.

METHODS

A systematic review of articles was conducted according to PRISMA and AMSTAR-2 guidelines. 11 studies were included in the analysis.

RESULTS

We included in our analysis 212 patients subdivided in three groups: 64 in the HIPEC group (57 with prophylactic intent and 7 with curative intent), 55 in the PIPAC group and 93 in the NIPEC group. Primary outcomes were represented by survival rates; we evidenced at an observation time of three years a survival of 24% in the HIPEC group (25.5% in the prophylactic arm and 6.2% in the curative arm), 5.3% in the PIPAC group and 7.9% in the NIPEC group.

CONCLUSIONS

HIPEC could be considered as a promising technique for prophylaxis and treatment of peritoneal metastasis (PM) in case of borderline resectable and locally advanced disease. Increased survival rates emerged without additional morbidity when surgical resection and CRS are possible. In addition, our data about PIPAC and NIPEC as palliative treatment in unresectable disease seems to identify more favorable survival rates compared to literature.

Synopsis of a clinical practice guideline for pancreatic ductal adenocarcinoma with peritoneal dissemination in Japan; Japan Peritoneal Malignancy Study Group

Patients with pancreatic ductal adenocarcinoma (PDAC) with peritoneal dissemination have a dismal prognosis because discontinuation of systemic chemotherapy is required for massive ascites or poor performance status. The natural history, diagnosis and treatment of PDAC with peritoneal dissemination have not been fully investigated. We systematically reviewed published information on the clinical diagnosis and treatment of PDAC with peritoneal dissemination using the PubMed database (2000-2020) and provided recommendations in response to clinical questions. This guideline was created according to the "Minds Clinical Practice Guideline Development Guide 2017". The literature quality and body of evidence were evaluated with the GRADE System and classified into four levels ("strong", "medium", "weak", "very weak"). The strength of each final recommendation was decided by a vote of committee members based on the GRADE Grid method. These guidelines address three subjects: diagnostic, chemotherapeutic, and surgical approaches. They include nine clinical questions and statements with recommendation strengths, evidence levels, and agreement rates, in addition to one "column". This is the English synopsis of the 2021 Japanese clinical practice guideline for PDAC with peritoneal dissemination. It summarizes the clinical evidence for the diagnosis and treatment of PDAC with peritoneal dissemination and provides future perspectives.

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.