Systemic Pharmacokinetics of Oxaliplatin After Intraperitoneal Administration by Electrostatic Pressurized Intraperitoneal Aerosol Chemotherapy (ePIPAC) in Patients with Unresectable Colorectal Peritoneal Metastases in the CRC-PIPAC Trial.

BACKGROUND: Electrostatic pressurized intraperitoneal aerosol chemotherapy (ePIPAC) is a palliative treatment for unresectable peritoneal metastases from various primary cancers. However, little is known about the systemic pharmacokinetics of oxaliplatin after ePIPAC. METHODS: Twenty patients with unresectable colorectal peritoneal metastases were treated with repetitive ePIPAC monotherapy with oxaliplatin (92 mg/m2) and a simultaneous intravenous bolus of leucovorin (20 mg/m2) and 5-fluorouracil (400 mg/m2). Samples were collected during each ePIPAC: whole blood at t = 0, t = 5, t = 10, t = 20, t = 30, t = 60, t = 120, t = 240, t = 360 and t = 1080 min for plasma and plasma ultrafiltrate concentrations; urine at t = 0, t = 1, t = 3, t = 5 and t = 7 days. Samples were analyzed using atomic absorption spectrometry. Pharmacokinetics were analyzed using nonlinear mixed-effects modeling. RESULTS: Four patients received one ePIPAC, three patients received two ePIPAC, and thirteen patients received ≥ 3 ePIPAC. The population pharmacokinetic models adequately described the pharmacokinetics of oxaliplatin after ePIPAC. The plasma ultrafiltrate Cmax of oxaliplatin reached 1.36-1.90 µg/mL after 30 min with an AUC0-24 h of 9.6-11.7 µg/mL * h. The plasma Cmax reached 2.67-3.28 µg/mL after 90 min with an AUC0-24 h of 49.0-59.5 µg/mL * h. The absorption rate constant (Ka) was 1.13/h. Urine concentrations of oxaliplatin rapidly decreased to less than 3.60 µg/mL in 90% of the samples at day 7. DISCUSSION: Systemic exposure to oxaliplatin after ePIPAC seemed comparable to that after systemic chemotherapy, as described in other literature. Since this is an indirect comparison, future research should focus on the direct comparison between the systemic exposure to oxaliplatin after ePIPAC and after systemic chemotherapy. TRIAL REGISTRATION: NCT03246321, Pre-results; ISRCTN89947480, Pre-results; NTR6603, Pre-results; EudraCT: 2017-000927-29, Pre-results.

The prevalence of nodular regenerative hyperplasia of the liver in long-term thiopurine-treated inflammatory bowel disease patients.

INTRODUCTION: Nodular regenerative hyperplasia (NRH) has been associated with thiopurine therapy in patients with inflammatory bowel disease (IBD), but prevalence and prognosis of NRH remain unclear. This study is a cross-sectional search for NRH in IBD patients with long-term azathioprine or 6-mercaptopurine treatment. MATERIAL AND METHODS: Thirty-three IBD patients with continuous azathioprine/6-mercaptopurine treatment for at least 5 years were included. Laboratory tests, thiopurine metabolite levels, liver histology, MRI were examined for NRH and signs of portal hypertension. RESULTS: NRH was not observed in this cohort of 33 patients. Nevertheless, some possibly related signs of vascular changes were found by MRI in three patients. Also, splenomegaly, which may be associated with portal hypertension, was found in one patient. No high thiopurine dose neither high metabolite levels were found in these patients. CONCLUSION: No NRH was found in this group of IBD patients with long-term azathioprine/6-mercaptopurine treatment. Larger multicenter studies are needed to determine the prevalence of NRH in thiopurine-treated IBD patients.

Repetitive electrostatic pressurised intraperitoneal aerosol chemotherapy (ePIPAC) with oxaliplatin as a palliative monotherapy for isolated unresectable colorectal peritoneal metastases: protocol of a Dutch, multicentre, open-label, single-arm, phase II study (CRC-PIPAC).

INTRODUCTION: Repetitive electrostatic pressurised intraperitoneal aerosol chemotherapy with oxaliplatin (ePIPAC-OX) is offered as a palliative treatment option for patients with isolated unresectable colorectal peritoneal metastases (PM) in several centres worldwide. However, little is known about its feasibility, safety, tolerability, efficacy, costs and pharmacokinetics in this setting. This study aims to explore these parameters in patients with isolated unresectable colorectal PM who receive repetitive ePIPAC-OX as a palliative monotherapy. METHODS AND ANALYSIS: This multicentre, open-label, single-arm, phase II study is performed in two Dutch tertiary referral hospitals for the surgical treatment of colorectal PM. Eligible patients are adults who have histologically or cytologically proven isolated unresectable PM of a colorectal or appendiceal carcinoma, a good performance status, adequate organ functions and no symptoms of gastrointestinal obstruction. Instead of standard palliative treatment, enrolled patients receive laparoscopy-controlled ePIPAC-OX (92 mg/m2 body surface area (BSA)) with intravenous leucovorin (20 mg/m2 BSA) and bolus 5-fluorouracil (400 mg/m2 BSA) every 6 weeks. Four weeks after each procedure, patients undergo clinical, radiological and biochemical evaluation. ePIPAC-OX is repeated until disease progression, after which standard palliative treatment is (re)considered. The primary outcome is the number of patients with major toxicity (grade ≥3 according to the Common Terminology Criteria for Adverse Events v4.0) up to 4 weeks after the last ePIPAC-OX. Secondary outcomes are the environmental safety of ePIPAC-OX, procedure-related characteristics, minor toxicity, postoperative complications, hospital stay, readmissions, quality of life, costs, pharmacokinetics of oxaliplatin, progression-free survival, overall survival, and the radiological, histopathological, cytological, biochemical and macroscopic tumour response. ETHICS AND DISSEMINATION: This study is approved by an ethics committee, the Dutch competent authority and the institutional review boards of both study centres. Results are intended for publication in peer-reviewed medical journals and for presentation to patients, healthcare professionals and other stakeholders. TRIAL REGISTRATION NUMBER: NCT03246321, Pre-results; ISRCTN89947480, Pre-results; NTR6603, Pre-results; EudraCT: 2017-000927-29, Pre-results.