Carboplatin dosing in children: calculation by different formulae.

Würthwein G, Krefeld B, Gerss J, Boos J

Zusammenfassung

Carboplatin dosing in children is based on renal function and there exists a wealth of formulae available for calculating the body surface area (BSA), the glomerular filtration rate (GFR), and the carboplatin dose.A fictitious group of children with different ages and body builds was 'constructed'. For comparison of formulae, bias and precision were assessed.BSA calculations according to DuBois-DuBois, Gehan-George, Mosteller, and Boyd showed good agreement. GFR calculations according to the weight-based Cole formula and the Léger formula gave comparable results. Regarding GFR in young children, the weight-and creatinine-based Cole and the Schwartz formula showed clear differences. Again, carboplatin dose calculations according to Marina, Newell, and Chatelut are comparable. Moreover, the precision of the creatinine measurement has a clear influence on the result of the dose calculation.The choice of the GFR formula is more important for the carboplatin dose calculation compared to the BSA or dose equation. GFR calculations in children show marked, age-dependent variations. A sequence of multiple calculation steps (especially for the Schwartz and Marina formulae) may lead to considerable uncertainty and proneness to error in the clinical routine. In high-risk patients, GFR should be measured precisely and complemented by therapeutic drug monitoring.