Infusional floxuridine-based therapy for patients with metastatic renal cell carcinoma

The treatment of patients with metastatic renal cell carcinoma (RCC) continues to pose a major clinical challenge. Previous studies have suggested that infusional floxuridine (FUDR) has antitumor efficacy and is well tolerated. To the authors knowledge the combination of infusional FUDR with biologic response modifiers (BRMs) has not been evaluated extensively in patients with metastatic RCC.

Thirty-nine previously untreated patients with metastatic RCC were treated with infusional FUDR at 0.075 mg/kg/day for 14 days of a 28-day cycle. Beginning with the second cycle of FUDR, 24 patients received subcutaneous interferon-alpha-2b (3 million U 3 times a week for Weeks 1 and 2) and 15 received subcutaneous interleukin-2 (IL-2) (5 million U/m(2) 5 days a week for 3 weeks, followed by 1 week off). The dose of FUDR was increased by 0.025 mg/kg each cycle until the maximum tolerated dose for each patient was reached.

Five patients receiving FUDR plus interferon achieved a partial response and 1 achieved a complete response whereas 3 patients receiving FUDR plus IL-2 achieved a partial response, for an overall response rate of 23%. The median survival for all patients was 21 months, and 8 patients still were alive 6-57+ months after the initiation of therapy. Toxicity was mild to moderate, and was comprised primarily of fatigue, diarrhea, dacryocystitis, and fluid retention (in the IL-2 cohort).

FUDR in conjunction with IL-2 or interferon appears to produce response rates comparable to those observed with other programs utilizing BRMs and generally is well tolerated. FUDR regimens may be useful in the treatment of metastatic RCC in the outpatient community setting.