[Correlations between clinical pharmacodynamics and pharmacokinetics of cisplatin and etoposide].

Currently, the dose of anticancer drugs is adjusted according to patient body surface area, although the best criterion for dose adjustment seems to be the plasma concentration of the drug, since a correlation has been established between plasma concentration and efficacy for several drugs. We report here similar results with etoposide and cisplatinum. The plasma concentration and the area under the curve (AUC) of etoposide and platinum (Pt) were higher in responders compared to non-responders, and etoposide clearance was higher in responders. The etoposide toxicity (assessed by the polymorphonuclear blood count) was higher in responders. There was a good correlation between the Pt concentration and creatininaemia. The AUC for Pt was significantly higher in patients with nausea and vomiting. There was no correlation between the infected dose of either drug and efficacy or toxicity. It is not possible to assign efficacy to either compound since they were injected simultaneously. We conclude that when the plasma etoposide or platinum concentrations are low, tumour response is unlikely.