Dose response relationship of cell killing by chemotherapeutic drugs on normal and cancer cells. At high doses the percentage of normal and cancer cells killed is very similar. For this reason, doses are chosen where anti-tumour activity exceeds normal cell death.[1]
As a result, there is high variability in the systemic chemotherapy drug concentration among patients dosed by BSA, and this variability has been demonstrated to be more than 10-fold for many drugs.[13][18] In other words, if two patients receive the same dose of a given drug based on BSA, the concentration of that drug in the bloodstream of one patient may be 10 times higher or lower compared to that of the other patient.[18] This variability is typical with many chemotherapy drugs dosed by BSA, and, as shown below, was demonstrated in a study of 14 common chemotherapy drugs.[13]