Pharmacodynamics of Oxaliplatin-Derived Platinum Compounds During Hyperthermic Intraperitoneal Chemotherapy (HIPEC): An Emerging Aspect Supporting the Rational Design of Treatment Protocols

Advances in the management of peritoneal malignancies

Peritoneal surface malignancies (PSMs) are usually associated with a poor prognosis. Nonetheless, in line with advances in the management of most abdominopelvic metastatic diseases, considerable progress has been made over the past decade. An improved understanding of disease biology has led to the more accurate prediction of neoplasia aggressiveness and the treatment response and has been reflected in the proposal of new classification systems. Achieving complete cytoreductive surgery remains the cornerstone of curative-intent treatment of PSMs. Alongside centralization in expert centres, enabling the delivery of multimodal and multidisciplinary strategies, preoperative management is a crucial step in order to select patients who are most likely to benefit from surgery. Depending on the specific PSM, the role of intraperitoneal chemotherapy and of perioperative systemic chemotherapy, in particular, in the neoadjuvant setting, is established in certain scenarios but questioned in several others, although more prospective data are required. In this Review, we describe advances in all aspects of the management of PSMs including disease biology, assessment and improvement of disease resectability, perioperative management, systemic therapy and pre-emptive management, and we speculate on future research directions.

Prolonged Exposure to Oxaliplatin during HIPEC Improves Effectiveness in a Preclinical Micrometastasis Model

Simple Summary

Absence of survival benefits when adding hyperthermic intraperitoneal chemotherapy (HIPEC) with oxaliplatin to cytoreductive surgery in peritoneal metastasis from colorectal cancer has recently been shown in the randomized controlled PRODIGE 7 trial. We therefore aimed to investigate the effects of this treatment modality in a preclinical micrometastasis model. Cancer cells were incubated with either patient samples obtained during HIPEC procedures or with defined oxaliplatin-containing solutions prepared according to clinically established HIPEC protocols. Our results demonstrate a limited effectiveness of short-term HIPEC in simulations with oxaliplatin to eliminate micrometastases, although we used platinum-sensitive cell lines for our model. Since these results are in line with findings from current research, our studies might offer further convincing evidence and potential explanations for HIPEC futility observed in clinical application.

Abstract

Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) was considered a promising treatment for patients with peritoneal metastasis from colorectal cancer. However, the recently published randomized controlled PRODIGE 7 trial failed to demonstrate survival benefits through the addition of short-term oxaliplatin-based HIPEC. Constituting a complex multifactorial treatment, we investigated HIPEC in a preclinical model concerning the elimination of minimal tumor residues, thereby aiming to better understand the size of effects and respective clinical trial results. Patient samples of peritoneal perfusates obtained during HIPEC treatments and oxaliplatin-containing solutions at clinically relevant dosages, conforming with established HIPEC protocols, were assessed regarding their ability to eliminate modelled ~100 µm thickness cancer cell layers. Impedance-based real-time cell analysis and classical end-point assays were used. Flow cytometry was employed to determine the effect of different HIPEC drug solvents on tumor cell properties. Effectiveness of peritoneal perfusate patient samples and defined oxaliplatin-containing solutions proved limited but reproducible. HIPEC simulations for 30 min reduced the normalized cell index below 50% with peritoneal perfusates from merely 3 out of 9 patients within 72 h, indicating full-thickness cytotoxic effects. Instead, prolonging HIPEC to 1 h enhanced these effects and comprised 7 patients’ samples, while continuous drug exposure invariably resulted in complete cell death. Further, frequently used drug diluents caused approximately 25% cell size reduction within 30 min. Prolonging oxaliplatin exposure improved effectiveness of HIPEC to eliminate micrometastases in our preclinical model. Accordingly, insufficient penetration depth, short exposure time, and the physicochemical impact of drug solvents may constitute critical factors.

A Prospective, Phase I/II, Open-Label Pilot Trial to Assess the Safety of Hyperthermic Intraperitoneal Chemotherapy After Oncological Resection of Pancreatic Adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a common fatal disease with unfavorable prognosis, even after oncological resection. To improve survival, adding hyperthermic intraperitoneal chemotherapy (HIPEC) has been suggested. Whether HIPEC entails disproportional short-term mortality is unknown and a prospectively determined adverse events profile is lacking. Since both pancreatic resection and HIPEC may relevantly influence morbidity and mortality, this uncontrolled single-arm, open-label, phase I/II pilot trial was designed to assess the 30-day mortality rate, treatment feasibility, and adverse events connected with HIPEC after oncological pancreatic surgery.

METHODS

This trial recruited patients scheduled for PDAC resection. A sample size of 16 patients receiving study interventions was estimated to establish a predefined margin of treatment-associated short-term mortality with a power of > 80%. Patients achieving complete macroscopic resection received HIPEC with gemcitabine administered at 1000 mg/m² body surface area heated to 42 °C for 1 hour.

RESULTS

Within 30 days after intervention, no patient died or experienced any adverse events higher than grade 3 that were related to HIPEC. Furthermore, treatment-related adverse events were prospectively documented and categorized as expected or unexpected. This trial supports that the actual mortality rate after PDAC resection and HIPEC is below 10%. HIPEC treatment proved feasible in 89% of patients allocated to intervention. Pancreatic fistulas, as key complications after pancreas surgery, occurred in 3/13 patients under risk.

CONCLUSION

Combined pancreas resection and gemcitabine HIPEC proved feasible and safe, with acceptable morbidity and mortality. Based on these results, further clinical evaluation can be justified.

REGISTRATION NUMBER

NCT02863471 ( http://www.clinicaltrials.gov ).

Wide variation in tissue, systemic, and drain fluid exposure after oxaliplatin-based HIPEC: results of the GUTOX study

Purpose

In this exploratory study, the effect of postprocedural flushing with crystalloids after oxaliplatin-based hyperthermic intraperitoneal chemotherapy (HIPEC) on platinum concentrations in peritoneal tissue, blood, and drain fluid was studied. Interpatient variability in oxaliplatin pharmacokinetics and the relation between platinum concentration in peritoneal fluid and platinum exposure in tissue and blood was explored.

Methods

Ten patients with peritoneal carcinomatosis of colorectal origin were treated with HIPEC including postprocedural flushing, followed by ten patients without flushing afterwards. Tissue, peritoneal fluid, blood, and drain fluid samples were collected for measurement of total and ultrafiltered platinum concentrations.

Results

Peritoneal tissue concentration and systemic ultrafiltered platinum exposure showed large inter individual variability, ranging from 65 to 1640 µg/g dry weight and 10.5 to 28.0 µg*h/ml, respectively. No effect of flushing was found on geometric mean platinum concentration in peritoneal tissue (348 vs. 356 µg/g dry weight), blood (14.8 vs. 18.1 µg*h/ml), or drain fluid (day 1: 7.6 vs. 7.7 µg/ml; day 2: 1.7 vs. 1.9 µg/ml). The platinum concentration in peritoneal fluid at the start of HIPEC differed twofold between patients and was positively correlated with systemic exposure (p = .04) and peak plasma concentration (p = .04).

Conclusion

In this exploratory study, no effect was found for postprocedural flushing on platinum concentrations in peritoneal tissue, blood, or drain fluid. BSA-based HIPEC procedure leads to large interpatient variability in platinum exposure in all compartments.

The study was registered at ClinicalTrials.gov on 7 December 2017 under registration number NCT03364907.

Overcoming Drug Resistance by Taking Advantage of Physical Principles: Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC)

Theoretical considerations as well as comprehensive preclinical and clinical data suggest that optimizing physical parameters of intraperitoneal drug delivery might help to circumvent initial or acquired resistance of peritoneal metastasis (PM) to chemotherapy. Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is a novel minimally invasive drug delivery system systematically addressing the current limitations of intraperitoneal chemotherapy. The rationale behind PIPAC is: (1) optimizing homogeneity of drug distribution by applying an aerosol rather than a liquid solution; (2) applying increased intraperitoneal hydrostatic pressure to counteract elevated intratumoral interstitial fluid pressure; (3) limiting blood outflow during drug application; (4) steering environmental parameters (temperature, pH, electrostatic charge etc.) in the peritoneal cavity for best tissue target effect. In addition, PIPAC allows repeated application and objective assessment of tumor response by comparing biopsies between chemotherapy cycles. Although incompletely understood, the reasons that allow PIPAC to overcome established chemoresistance are probably linked to local dose intensification. All pharmacological data published so far show a superior therapeutic ratio (tissue concentration/dose applied) of PIPAC vs. systemic administration, of PIPAC vs. intraperitoneal liquid chemotherapy, of PIPAC vs. Hyperthermic Intraperitoneal Chemotherapy (HIPEC) or PIPAC vs. laparoscopic HIPEC. In the initial introduction phase, PIPAC has been used in patients who were quite ill and had already failed multiple treatment regimes, but it may not be limited to that group of patients in the future. Rapid diffusion of PIPAC in clinical practice worldwide supports its potential to become a game changer in the treatment of chemoresistant isolated PM of various origins.

Pharmacokinetics of cisplatin during open and minimally-invasive secondary cytoreductive surgery plus HIPEC in women with platinum-sensitive recurrent ovarian cancer: a prospective study

Objective

Evidences from animal models seem to suggest that minimally invasive surgery may enhance cisplatin diffusion when the drug is administered in the context of post-operative hyperthermic intraperitoneal chemotherapy (HIPEC). The present study evaluates the cisplatin pharmacokinetic profile in a prospective series of women with platinum sensitive recurrent epithelial ovarian cancer treated with open secondary cytoreductive surgery (O-SCS) or minimally-invasive secondary cytoreductive surgery (MI-SCS).

Methods

Cisplatin levels were assessed at 0, 20, 40, 60, and 120 minutes in: 1) blood samples, 2) peritoneal perfusate, and 3) peritoneal biopsies at the end of HIPEC. Median C_max has been used to identify women with high and low drug levels. Progression-free survival (PFS) was calculated as the time elapsed between SCS+HIPEC and secondary recurrence or last follow-up visit.

Results

Nine (45.0%) women received MI-SCS, and 11 (55.0%) O-SCS. At 60 minutes, median cisplatin C_max in peritoneal tissue was higher in patients treated with MI-SCS compared to O-SCS (C_max=8.262 µg/mL vs. C_max=4.057 µg/mL). Furthermore, median cisplatin plasma C_max was higher in patients treated with MI-SCS compared to O-SCS (C_max=0.511 vs. C_max=0.254 µg/mL; p-value=0.012) at 120 minutes. With a median follow-up time of 24 months, women with higher cisplatin peritoneal C_max showed a longer PFS compared to women with low cisplatin peritoneal levels (2-years PFS=70% vs. 35%; p-value=0.054).

Conclusions

We demonstrate for the first time that minimally invasive route enhances cisplatin peritoneal tissue uptake during HIPEC, further evaluations are needed to confirm the correlation between peritoneal cisplatin levels after HIPEC and survival.

Trial Registration

ClinicalTrials.gov Identifier: NCT01539785

Systematic Review of Variations in Hyperthermic Intraperitoneal Chemotherapy (HIPEC) for Peritoneal Metastasis from Colorectal Cancer

Background: Cytoreductive surgery (CRS), followed by hyperthermic intraperitoneal chemotherapy (HIPEC), combines radical surgery with abdominal heated chemotherapy, constituting a multimodal treatment approach. Since clear standards for HIPEC conduct in colorectal carcinoma (CRC) are lacking, we aimed to provide a comprehensive structured survey. Data sources and study eligibility criteria: A systematic literature search was performed in PubMed, with keywords “HIPEC” and “colorectal cancer”, according to established guidelines. Articles were systematically screened, selecting 87 publications complemented by 48 publications identified through extended search for subsequent synthesis and evaluation, extracting inter alia details on used drugs, dosage, temperature, exposure times, and carrier solutions. Results: Compiled publications contained 171 reports on HIPEC conduct foremost with mitomycin C and oxaliplatin, but also other drugs and drug combinations, comprising at least 60 different procedures. We hence provide an overview of interconnections between HIPEC protocols, used drugs and carrier solutions as well as their volumes. In addition, HIPEC temperatures and dosing benchmarks, as well as an estimate of in vivo resulting drug concentrations are demonstrated. Conclusions and implications: Owing to recent developments, HIPEC conduct and practices need to be reassessed. Unfortunately, imprecise and lacking reporting is frequent, which is why minimal information requirements should be established for HIPEC and the introduction of final drug concentrations for comparability reasons seems sensible.

Hyperthermic intraperitoneal chemotherapy with oxaliplatin for peritoneal carcinomatosis: a clinical pharmacological perspective on a surgical procedure

Cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC) has become the standard of care in the treatment of patients with peritoneal carcinomatosis of colorectal origin. The use of oxaliplatin for HIPEC has gained popularity. Although the HIPEC procedure is adopted throughout the world, major differences exist between treatment protocols regarding the carrier solution, perfusate volume, use of an open or closed technique, duration of the perfusion and application of additional flushing. These differences can influence the pharmacokinetics and pharmacodynamics of oxaliplatin and might thereby have an impact on the efficacy and/or safety of the treatment. Clinicians should be aware of the clinical importance of oxaliplatin pharmacology when performing HIPEC surgery. This review adds new insights into the complex field of the pharmacology of HIPEC and highlights an important worldwide problem: the lack of standardization of the HIPEC procedure.