Clinical relevance of biologic factors in male breast cancer

There is ample information on the clinical role of biologic factors in fema le breast cancer: urokinase-type plasminogen activator (uPA), its receptor uPAR, its inhibitors PAI-1 and PAI-2, cathepsin D and pS2-protein. However such reports are missing or very rare for male breast cancer. We determined the cytosolic levels of oestrogen receptor (ER), progesterone receptor (Pg R), cathepsin D, pS2-protein, uPA, uPAR, PAI-1 and PAI-2 of the primary tum our tissues from 40 male breast cancer patients. The tumour levels were com pared with those of 180 matched females and 4114 historic females with brea st cancer. In male breast tumours the level of PgR was higher, those of uPA , PAI-1, PAI-2 and cathepsin D lower. The tumour level of ER in men was sim ilar to those in the matched and postmenopausal women, but much higher than those in the historic women. Male breast cancer seems to be biologically d ifferent from female breast cancer. Correlation of the eight cell biologic factors with disease outcome showed that PAI-1 (p = 0.03) was the only inde pendent predictive factor for poor prognosis in male breast cancer.