536 Background: We have recently demonstrated that urokinase Plasminogen Activator (uPA), together with its inhibitor PAI-1, have prognostic value in hormone-receptor positive early breast cancer, and can be measured in FFPE archived tumor samples. We have now aimed to validate the prognostic role of uPA protein expression in FFPE archived tumor samples in an independent cohort of endocrine-treated breast cancer patients. Methods: 303 postmenopausal women with hormone receptor–positive, early breast cancer who had received 5 years of endocrine therapy in the prospectively designed ABCSG-08 trial, and in whom FFPE tumor tissue was available, were included in this analysis. Stromal uPA and PAI-1 protein expression was evaluated by immunohistochemistry and correlated with distant recurrence-free survival (DRFS) and overall survival (OS). Results: Stromal uPA was detected in 132 of 297 tumors (44.4%), and 74 out of 269 samples (27.5%) exhibited stromal PAI-1, while co-expression of both proteins was found in 48 of 294 (16.3%) samples. Neither uPA nor PAI-1 expression were associated with tumor size, age, nodal status, grading, or receptor status. Patients whose tumor stroma expressed uPA protein were more likely to have a shorter DRFS (adjusted HR for relapse: 2.78; 95% CI 1.31-5.93; p=0.008 Cox regression analysis) and OS (adjusted HR for death: 1.29; 95% CI 0.86-12.50; p=0.161) than women without uPA expression. No such association was observed for PAI-1 and for the uPA/PAI1 ratio. After a median follow-up of 5.6 years women with uPA-positive tumors experienced a significantly shorter DRFS (93.3% vs 84.8%; p<0.013 log rank test) and tended to have a worse OS (83.0.4% vs 77.3%; p=0.106) compared to women with uPA negative tumors. Conclusions: By confirming the clinical utility of stromal uPA IHC in archived breast cancer samples from an independent prospective randomized trial, we now provide level 1b evidence for a prognostic role of stromal uPA in women with endocrine-responsive early breast cancer.
Prognostic role of serum thymidine kinase 1 kinetics during neoadjuvant chemotherapy for early breast cancer
