Journal of Clinical Oncology, Vol 20, Issue 4 (February), 2002: 1000-1007 © 2002 American Society for Clinical Oncology
Clinical Relevance of Invasion Factors Urokinase-Type Plasminogen Activator and Plasminogen Activator Inhibitor Type 1 for Individualized Therapy Decisions in Primary Breast Cancer Is Greatest When Used in Combination By Nadia Harbeck, Ronald E. Kates, Manfred Schmitt From the Clinical Research Group, Department of Obstetrics and Gynecology, Technical University of Munich, Munich, Germany.
Address reprint requests to Nadia Harbeck, MD, Frauenklinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, Ismaninger Strasse 22, D-81675 Munich, Germany; email: nadia.harbeck@ lrz.tum.de.
PURPOSE: A strong prognostic impact of urokinase-type plasminogen activator (uPA) and its inhibitor and plasminogen activator inhibitor type 1 (PAI-1) as individual factors is well established in breast cancer. The improvement in clinical risk assessment gained by combining these factors is evaluated here.
PATIENTS AND METHODS: uPA and PAI-1 levels were prospectively measured by enzyme-linked immunosorbent assay in tumor tissue extracts of 761 patients with primary breast cancer.
RESULTS: In the clinically important subgroup of node-negative patients without adjuvant systemic therapy (n = 269; median follow-up, 60 months), the clinical value of testing both uPA and PAI-1 is demonstrated. The criterion either or both high identifies with high sensitivity the patients at high relapse risk while keeping more than half in the low-risk group. uPA/PAI-1 is the strongest predictor of disease-free survival and overall survival; patients with high uPA/PAI-1 have an increased relapse risk (P < .001; relative risk, 4.8; 95% confidence interval [CI], 2.5 to 9.1), in particular for early relapse. Even within risk groups stratified by established criteria (nodal or menopausal status, tumor size, grade, or steroid hormone receptors), uPA/PAI-1 provides significant risk group discrimination. In the whole collective, the significant interaction between uPA/PAI-1 and adjuvant systemic therapy suggests a benefit from adjuvant therapy in high-risk patients as defined by uPA/PAI-1.
CONCLUSION: The clinical relevance of the two tumor-invasion factors uPA and PAI-1 is greatest when they are used in combination. The particular combination of uPA and PAI-1 (both low v either or both high) is superior to either factor alone and supports risk-adapted individualized therapy decisions. |