Pharmacokinetics of carboplatin in a hemodialysis patient with small-cell lung cancer

Abstract

We examined a method to determine the dose of carboplatin and the timing of hemodialysis in carboplatin-based chemotherapy for a hemodialysis patient with cancer. Carboplatin-based chemotherapy was performed for a patient with small-cell lung cancer who was receiving hemodialysis. The dose of carboplatin was calculated based on body surface area in the first cycle (480 mg/body, Day 1) and based on the Calvert formula with the aim of achieving AUC of 5 mg/ml min in the second cycle (170 mg/body, Day 1). Carboplatin was continuously infused for 1 h on Day 1 of each cycle. Hemodialysis was performed for 4 h beginning 1 h after administration of carboplatin. The AUC of free carboplatin administered in the first and second cycles was 13.45 and 5.74 mg/ml min, respectively, and t (1/2) was 24.66 and 21.84 h, respectively. Protein binding ratio depended on the time after administration and reached a value ≥50% only at ≥24 h administration. Based on the results of this study, a value close to the targeted AUC can be obtained in a hemodialysis patient with cancer when carboplatin is administered at a dose determined based on the Calvert formula. These results may be useful to achieve a targeted AUC in hemodialysis patients. A certain amount of carboplatin can be eliminated by performing hemodialysis in an early phase when protein binding ratio is low after transition to the elimination phase to enable stable the concentration.