Comparative prognostic value of cathepsin D and urokinase plasminogen activator, detected by immunohistochemistry, in primary breast carcinoma

The lysosomal protease Cathepsin D and the serine protease urokinase plasminogen activator (uPA) are suspected to indicate poor prognosis in primary breast carcinoma. We tested Cathepsin D and uPA immunohistochemically in 281 surgical specimens of primary ductal infiltrating breast carcinomas. Staining was evaluated, taking intracytoplasmic immunoreactions into account, in tumour cells and tumour infiltrating macrophages. Positivity was established in 48.4% and 58.0% of tissue samples for cathepsin D and uPA respectively (co-expression: 67.6%). In patients with cathepsin D- or uPA-positive tumours, relapses were more frequent and disease-free survival was shorter irrespective of nodal status, receptor status or menopausal status, (median observation time 74 months). However, this trend was statistically significant only for cathepsin D. With stepwise cox regression analysis, borderline significance (p = 0.07) was calculated for cathepsin D only in node-negative was patients. The combination of cathepsin D with uPA measurements did nor enhance its prognostic value. Immunohistochemical detection of Cathepsin D could potentially be used to identify patients with poor prognosis in the group of node negative breast cancer patients.