A phase II study of irinotecan in patients with advanced renal cell carcinoma

BACKGROUND. Patients with disseminated renal cell carcinoma (RCC) have a poor outcome, and the disease is considered highly resistant to chemotherapy. Irinotecan is an active drug in the treatment of a number of neoplastic diseases and is not concerned with the multidrug-resistance phenotype of tumor cells, a common mechanism of drug inactivation and resistance in patients with RCC. Therefore, the authors tested the antitumor activity of irinotecan in patients with RCC. METHODS. Patients with disseminated RCC received irinotecan (350 mg/m²) every 3 weeks. The primary objective of the study was to determine the overall response rate. Two groups of patients were defined: previously treated patients (Group A) and nonpretreated patients (Group B). RESULTS. Forty-two eligible patients were recruited: Twenty-six patients (Group A) had received previous chemotherapy or immunotherapy, and 16 patients had received no previous systemic therapy (Group B). The median number of cycles received per patient was 3 cycles (range, 1-6 cycles). A dose reduction was required in only 8% of cycles. Two patients, one in each group, had minor responses. Eleven patients (42%) in Group A and 1 patient (12%) in Group B had disease stabilization. Overall, therapy was tolerated well. Grade 4 neutropenic fever occurred in 17% of patients. The 1-year overall survival rate was 61% (95% confidence interval, 42-80%) in Group A and 19% (95% confidence interval, 0-49%) in Group B. CONCLUSIONS. Irinotecan was tolerated well and had limited activity in patients with disseminated RCC at the dose and schedule used in the current study. A high percentage of disease stabilization was observed in cytokine-pretreated patients.