PROGNOSTIC-SIGNIFICANCE OF IMMUNOHISTOCHE MICAL DETECTION OF UROKINASE PLASMINOGEN-ACTIVATOR IN PRIMARY BREAST CARCINOMAS

There is ample evidence that the protease urokinase plasminogen activa tor (uPA) plays a role in invasion and spread of tumours. Several publ ications suggest its biochemical measurement in tumour cytosols to be of prognostic significance in breast carcinomas. Our study set out to determine whether the immunohistochemical detection of uPA in formalin -fixed, paraffin-embedded primary breast cancer tissues is of prognost ic relevance. We tested 269 surgical specimens of primary ductal infil trating carcinoma immunohistochemically using a modified avidin-biotin method. Some 57 % of carcinoma specimens yielded specific positive st aining in tumour cells. Detection of uPA correlated to tumour grade (P = 0.04), and to the detected level of the proliferation marker PCNA ( P = 0.002), but not to patients' age or menopausal status, tumour size , nodal or steroid receptor status (P > 0.05). At median 68 months' fo llow-up, 34 % of patients had experienced tumour relapse and 28 % had died from cancer. Clinical course was correlated significantly to tumo ur size, tumour grade, nodal and steroid hormone receptor status (P < 0.05). Immunohistochemical detection of uPA, however, could not be dem onstrated to be of any prognostic significance with regard to relapse- free or overall survival (P > 0.05) in the total study group or in the NO (n = 120) and N + (n = 144) subgroups, regardless of whether univa riate or multivariate analysis was applied.