title: Evidence for the clinical use of tumour markers.
abstract: Testing for tumour markers should only be performed if it results in a better patient outcome, increased quality of life or reduced overall cost of care. Ideally, the clinical value of a tumour marker should be validated in a large prospective study or a meta-analysis of small-scale retrospective/prospective studies (i.e. a level 1 evidence study) prior to routine use. Markers that have been validated in such a level 1 evidence study include carcinoembryonic antigen in the surveillance of patients with diagnosed colorectal cancer, alphafetoprotein, human chorionic gonadotrophin and lactate dehydrogenase for evaluating prognosis in patients non-seminomatous germ cell tumours, CA 125 for monitoring therapy in patients with ovarian cancer, oestrogen receptors for predicting response to hormone therapy in breast cancer, HER-2 for predicting response to trastuzumab in patients with advanced breast cancer and urokinase plasminogen activator/plasminogen activator inhibitor type 1 for determining prognosis in breast cancer. Although currently in widespread use, the value of prostate-specific antigen in screening for prostate cancer has yet to be validated in a large prospective randomized trial.
authors.affiliation: Department of Nuclear Medicine, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland. Michael.J.Duffy@ucd.ie
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Duffy
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood; D002986:Clinical Trials as Topic / Q000379:methods; D019317:Evidence-Based Medicine; D006801:Humans; D009369:Neoplasms / Q000097:blood / Q000175:diagnosis*; D011237:Predictive Value of Tests
chemical_list: D014408:Biomarkers, Tumor