PIPAC for Gastrointestinal Malignancies

Educational Review: Updates on Therapeutic Strategies for Gastric Cancer with Peritoneal Metastasis

Gastric cancer (GC) commonly presents in advanced stages with metastatic spread to the peritoneal cavity, and outcomes associated with gastric cancer with peritoneal metastasis (GCPM) continue to carry a dismal prognosis. Persistent challenges in the detection of peritoneal metastasis (PM) have resulted in a relative paucity of high-quality data to inform management decisions. Several consensus groups have published recommendations to guide management, including most recently the National Comprehensive Cancer Network guidelines, which now include cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) as a potential treatment modality in select patients with GCPM. Multiple clinical trials have investigated the use of CRS/HIPEC and other peritoneal-directed therapies, such as intraperitoneal chemotherapy (IPC) and pressurized intraperitoneal aerosolized chemotherapy (PIPAC). As high-volume centers work to incorporate such therapies into their practice, ongoing clinical trials are aimed at understanding their efficacy. Recent findings have improved understanding of the mechanisms and pathophysiology underlying GCPM while the discovery of novel targets offers potential for drug development and therapeutic strategies to overcome treatment resistance. This review highlights recent advancements and addresses the persistent challenges in managing GCPM while also offering a comprehensive summary of current guidelines and treatment strategies.

Diagnostic value of vascular endothelial growth factor (VEGF) levels in gastrointestinal cancers with ascites - A cross sectional study

Objective

Malignant ascites is suggestive of peritoneal carcinomatosis. The distinction between malignant and non-malignant ascites in a patient with malignancy is important, as it alters the management and prognosis. Current diagnostic methods are imaging, cytology, and diagnostic laparoscopy, all of which have low sensitivities. The vascular endothelial growth factor (VEGF) is essential for tumour growth and, hence, ascitic VEGF levels can be a diagnostic method for malignant ascites.

Material and Methods

This cross-sectional study was conducted in patients with gastrointestinal malignancies and ascites. The calculated sample size was 68 patients, who were divided into those who were truly positive or negative for malignant ascites based on a composite gold standard, comprising cytology, contrast enhanced computed tomography, and laparoscopy. The ascitic VEGF levels in these patients were compared.

Results

A total of 84 patients were enrolled, of whom 60.71% were found to have malignant ascites. It was found that the greater the volume of ascites, the greater the statistical likelihood of finding truly malignant ascites. The ascitic VEGF levels had a non-normal distribution, with median values of 783.64 and 41.12 pg/mL for malignant and non-malignant ascites (p<0.001). Using a receiver operating characteristics curve, a cut-off of 83.68 pg/mL was obtained, with a sensitivity of 100% and a specificity of 93.94%.

Conclusion

This study demonstrates that ascitic VEGF levels are significantly elevated in patients with gastrointestinal malignancies and malignant ascites and hence can reliably be used for diagnosing malignant ascites. This study also shows that massive ascites and well-differentiated tumours have a higher rate of peritoneal carcinomatosis.

Chemotherapy Options for Locally Advanced Gastric Cancer: A Review

Cancers represent a significant global health burden, affecting millions of individuals each year [...].

Management of Peritoneal Metastasis in Patients with Pancreatic Ductal Adenocarcinoma

The peritoneum is the second most common site of metastasis in patients with pancreatic ductal adenocarcinoma (PDAC). Up to half of all patients that undergo curative-intent resection eventually develop peritoneal metastasis (PM), which accounts for significant morbidity and drives mortality. Despite recent advances in management, PM is associated with very poor prognosis, which is often measured in weeks to months. Clinical manifestations including bowel obstruction, ascites, and urinary obstruction have profound impact on quality of life. Even with relatively advanced disease, PM often remains occult on imaging and thus tend to be underdiagnosed and understudied. Many patients with peritoneal-only PM are excluded from clinical trials because response cannot be measured by standard radiographic criteria. Furthermore, as patients with PM are not eligible for surgical resection and low-volume peritoneal disease is often not amenable to percutaneous biopsy, tissue samples for peritoneal-specific translational studies are limited. Intraperitoneal therapeutics have been proposed as an attractive option for PM, as better penetration of tumor tissue can be achieved with less systemic toxicity compared with intravenous chemotherapy. Heated intraperitoneal chemotherapy (HIPEC), typically combined with cytoreductive surgery (CRS), is an option for select patients with PM from gynecologic or gastrointestinal primary, and for patients with primary peritoneal mesothelioma. However, the incorporation of locoregional therapy for PM in patients with PDAC has been poorly studied given the aggressive nature of pancreatic cancer and overall poor prognosis. With recent advances in existing treatment options, there may be a subset of patients who may derive benefits from locoregional control with cytoreduction and/or intraperitoneal chemotherapy. Critically, additional work is needed to determine PM-favorable clinical and tumoral predictive biomarkers to identify patients who may benefit from a more aggressive approach. We describe the current state of management of patients with peritoneal metastasis from PDAC and review the available data exploring peritoneal-directed therapy with cytoreductive surgery and/or intraperitoneal chemotherapy.

Advances in microsphere-based therapies for peritoneal carcinomatosis: challenges, innovations, and future prospects

INTRODUCTION

Clinical outcomes for the treatment of peritoneal carcinomatosis (PC) have remained suboptimal. Microsphere-based intraperitoneal chemotherapy has shown considerable potential in preclinical studies. However, due to the complications associated with peritoneal adhesions, there has been a lack of comprehensive reviews focusing on the progress of microsphere applications in the treatment of PC.

AREAS COVERED

We provide an overview of the current clinical treatment strategies for PC and analyze the potential advantages of microspheres in this context. Regarding the issue of peritoneal adhesions induced by microspheres, we investigate the underlying mechanisms and propose possible solutions. Furthermore, we outline the future directions for the development of microsphere-based therapies in the treatment of PC.

EXPERT OPINION

Microspheres formulated with highly biocompatible materials to the peritoneum, such as sodium alginate, gelatin, or genipin, or with an optimal particle size (4 ~ 30 μm) and lower molecular weights (10 ~ 57 kDa), can prevent peritoneal adhesions and improve drug distribution. To further enhance the antitumor efficacy, enhancing the tumor penetration capability and specificity of microspheres, optimizing intraperitoneal distribution, and addressing tumor resistance have demonstrated significant potential in preclinical studies, offering new therapeutic prospects for the treatment of PC.

Evolution in the Surgical Management of Gastric Cancer Peritoneal Metastases

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

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.

Amplifying Curcumin's Antitumor Potential: A Heat-Driven Approach for Colorectal Cancer Treatment

Introduction

Peritoneal metastases from colorectal cancer (CRC) present a significant clinical challenge with poor prognosis, often unresponsive to systemic chemotherapy. Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment approach for select patients. The use of curcumin, a natural compound with antitumor properties, in HIPEC is of interest due to its lower side effects compared to conventional drugs and potential for increased efficacy through direct delivery to the peritoneal cavity.

Methods

An in vitro hyperthermic model was developed to simulate clinical HIPEC conditions. Three colon cancer cell lines (SK-CO-1, COLO205, SNU-C1) representing different genetic mutations (p53, KRAS, BRAF) were treated with either curcumin (25 µM) or mitomycin-C (1 µM) for 1, 2, or 3 hours. Post-treatment, cells were incubated at 37°C (normothermia) or 42°C (hyperthermia). Cell viability and proliferation were assessed at 24, 48 and 72 hours post-treatment using Annexin V/PI, MTT assay, trypan blue exclusion, and Hoffman microscopy.

Results

Hyperthermia significantly enhanced the antitumor efficacy of curcumin, evidenced by a two-fold reduction in cell viability compared to normothermia across all cell lines. In the SNU-C1 cell line, which harbors a p53 mutation, mitomycin-C failed to significantly impact cell viability, unlike curcumin, suggesting mutation-specific differences in treatment response.

Discussion

The findings indicate that hyperthermia augments the antitumor effects of curcumin in vitro, supporting the hypothesis that curcumin could be a more effective HIPEC agent than traditional drugs like mitomycin-C. Mutation-associated differences in response to treatments were observed, particularly in p53 mutant cells. While further studies are needed, these preliminary results suggest that curcumin in HIPEC could represent a novel therapeutic strategy for CRC patients with peritoneal metastases. This approach may offer improved outcomes with fewer side effects, particularly in genetically distinct CRC subtypes.