Intraperitoneal carboplatin: rationale and experience

We conducted a phase I/II trial of intraperitoneal (IP) carboplatin in 27 patients with advanced gynecologic malignancies. This was based on the known activity of carboplatin in ovarian cancer and pharmacologic measurements that predict a favorable ratio of IP to plasma drug exposure when carboplatin is administered by the IP route. All patients had extensive prior therapy with cisplatin (mean dose, 554 mg/m2). Starting dose was 200 mg/m2, which was escalated to 500 mg/m2. Patients with compromised renal function (creatinine clearance 30 to 60 mL/min) had slower escalations than patients with creatinine clearances greater than 60 mL/min. Myelosuppression, especially thrombocytopenia, was the dose-limiting toxicity. In pretreated patients, we recommend a starting dose of 400 mg/m2. Patients with creatinine clearances of 30 to 60 mL/min should start at the lower dose of 200 mg/m2. This is in general agreement with the results of other trials of IP carboplatin. Measurements of IP carboplatin in preclinical studies predict less tissue penetration by carboplatin than the parent compound cisplatin. Nevertheless, in our series of heavily pretreated patients receiving IP carboplatin, eight patients remained free of disease progression for more than 2 years. Further trials of IP carboplatin are indicated.