Tumour markers: Current status and future applications

Abstract

A variety of tumour marker tests are available for three major intended uses: screening, diagnosis, and monitoring. For each use, performance characteristics need to be well established. The value of a marker depends heavily on two predominant performance parameters — sensitivity and specificity. These parameters must be established with respect to the intended clinical use of the marker. Therefore, it is important to balance the analyticdclinical sensitivity and the resultant claims for the test. The FDA review and evaluation of a tumour marker test focuses upon the intended use and the clinical utility of the marker. The sponsor must prove all specific claims. The data must support well-designed scientific protocols and clinical studies[1].

Generally, a tumour marker test is evaluated based on its intended clinical use, epidemiological sensitivity, specificity, and prevalence. A particular tumour marker test will have higher predictive value when it is applied to a population with a higher prevalence of the type of cancer being studied. Clinical utility for screening use may be limited by low prevalence [2].