Due to the wide interindividual variability in pharmacokinetics and
therapeutic response of cancer patients towards anticancer drugs,
pharmacogenomic-assisted dose optimization and/or application of
therapeutic drug monitoring service could be of benefit. For some drugs
like irinotecan used in solid tumors, dose optimization may be achieved if
the oncologist depends on pharmacogenomic approach. On the other hand,
dose adjustment of some other anticancer drugs like tamoxifen used in
breast cancer can be affected more by application of therapeutic drug
monitoring of its active metabolite; endoxifen.