Evaluation of Biomarkers

Biomarkers are increasingly studied in medical research. In recent history, the use of biomarkers in diagnosis and staging of cancer has increased. When a biomarker is considered for use the biomarker first has to be evaluated for its usefulness. There are several ways to evaluate new biomarkers; a systematic way to evaluate new technologies in medicine is called Health Technology Assessment (HTA). Within this framework, both the effectiveness and the cost-effectiveness of a new biomarker are assessed. A new biomarker should not be tested on its own, but within the body of knowledge that exists. Some techniques to do this include (improvement in) the area under the curve (AUC) of a receiver operating characteristic curves with all possible cut-offs for predictions, the Net Reclassification Improvement (NRI), and decision curve analysis (DCA) over a plausible range of cut-off for predictions.

In this thesis, the focus is on the evaluation of biomarkers with an application in urological cancers. Both the effectiveness of biomarkers as well as the cost-effectiveness is considered, with an application in two urological cancers: prostate cancer and bladder cancer.