Review ArticleTarget Concentration Intervention in Oncology Where Are We At?Saleem, Mohamed MBBS*,†; Dimeski, Goce PhD‡,§; Kirkpatrick, Carl M. PhD¶,‖; Taylor, Paul J. BSc*,‡; Martin, Jennifer H. PhD*,‡ Author Information *School of Medicine Southside, The University of Queensland †Department of Clinical Biochemistry, IMVS/SA Pathology, Adelaide ‡Princess Alexandra Hospital, Woolloongabba, Queensland §Chemical Pathology, Pathology, Queensland ¶School of Pharmacy, The University of Queensland ‖Center for Medicine Use and Safety, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Australia. Correspondence: Mohamed Saleem, MBBS, Department of Clinical Biochemistry, IMVS/SA Pathology, Frome Road, Adelaide 5000, Australia (e-mail: [email protected]). The authors declare no conflict of interest. Received December 18, 2011 Accepted March 10, 2012 Therapeutic Drug Monitoring: June 2012 - Volume 34 - Issue 3 - p 257-265 doi: 10.1097/FTD.0b013e3182557342 Buy Metrics Abstract Therapeutic drug monitoring (TDM) and more recently target concentration intervention (TCI) have been widely used in clinical practice for the optimization of drug treatment. TDM and TCI have been applied most frequently in the cardiovascular, respiratory, neurology, and infectious disease areas because the medications used here have both narrow therapeutic indices and a clear relationship between concentration and effect. However, apart from drugs such as methotrexate and 5-fluorouracil, the clinical application of TDM/TCI in oncology is minimal. An important reason for this is that a therapeutic index for most anticancer agents has not been established. However, in the last 20 years, relationships between plasma drug concentrations and clinical outcome have been defined for various chemotherapeutic agents. Defining concentration–effect relationships is also complicated by the fact that cancer is almost always treated with multiple drugs given in combination making the precise definition of the pharmacodynamics of individual agents difficult. The increase in patients with obesity and also those underweight adds to the complexity of effective oncology treatment. This review describes some of the evidence that supports the use of TDM/TCI in oncology. It is proposed that as more patients previously ineligible for chemotherapy become eligible, TDM/TCI may play a critical role in optimizing chemotherapy outcomes. However, pharmacokinetic–pharmacodynamic research to investigate both therapeutic benefit and feasibility in daily clinical practice is required. © 2012 Lippincott Williams & Wilkins, Inc.