Abstract
Aim: In our study we examined whether anthropometric and body
composition parameters, i.e. body surface area (BSA), lean body mass
(LBM) and total body weight (TBW), are correlated with docetaxel
clearance and exposure. In addition, LBM, TBW and a fixed dose were
compared to BSA as dosing parameters for dose individualisation of
docetaxel.
Methods: Thirty-six patients affected by breast or
castration-resistant prostate carcinoma receiving docetaxel chemotherapy
entered the study. LBM was measured by a Dual Energy Xray Absorptiometry
(DEXA) scanner before treatment. Blood samples were collected up to 180
minutes after dosing to analyse docetaxel concentrations and to
determine individual pharmacokinetic (PK) parameters.
Results: No significant correlations were found between the
docetaxel pharmacokinetic parameters clearance and volume of
distribution and the anthropometric and body composition variables BSA,
LBM and TBW. AUC was significantly but poorly correlated with BSA
(r=0.452 [p=0.016]) and with TBW (r=0.476 (p=0.011]). The Mean
Absolute Percentage Error and Mean Error of simulated dosing based on
LBM and fixed dosing ME were not significant different compared to BSA.
For TBW, only the MAPE of dosing was significant higher compared to BSA
(24.1 vs. 17.1, P=0.001).
Conclusion: There is no correlations between docetaxel
pharmacokinetics and the anthropometric and body composition variables
BSA, LBM and TBW. Dose individualisation of docetaxel based on LBM or
TBW or fixed dosing cannot be recommended over BSA based dosing.