Acute and cumulative effects of carboplatin on renal function

Abstract

Carboplatin, a cisplatin analogue, has no reported nephrotoxicity in phase I/II studies, assessed by creatinine clearance. We prospectively determined and renal function in 10 untreated lung cancer patients with normal baseline renal function, treated with carboplatin 400 mg m-2 day 1 and vincristine 2 mg day 1 and 8 every 4 weeks (max. five cycles) by means of clearance studies with 125I-sodium thalamate and 131I-hippurate to determine GFR and ERPF respectively. Tubular damage was monitored by excretion of tubular enzymes and relative .beta.2-microglobulin clearance. During the first course no changes in renal function were seen. After the second course a significant fall in GFR and ERPF started, ultimately leading to a median decrease in GFR to 19.0% (range 6.8-38.7%) and in ERPF of 14% (range 0-38.9%). No increases in the excretion of tubular enzymes or changes in the relative .beta.2-microglobulin clearances were seen. We conclude form our data that carboplatin causes considerable loss of renal function. Monitorinng renal function. Monitoring renal function in patients treated with multiple courses of carboplatin is warranted.