Breast-conserving therapy: proteases as risk factors in relation to survival after local relapse

To evaluate whether cathepsin D, urokinase-type plasminogen activator (uPA), its inhibitor, plasminogen activator inhibitor-1 (PAI-1), or clinical factors can predict which patients are at risk for developing distant metastases after local recurrence (LR).

Of 1,630 patients treated with breast-conserving surgery and radiotherapy of the breast between 1980 and 1992, LR developed in 171 as a first event. From the available primary tumor tissues, we determined the cytosolic levels of cathepsin D, uPA and PAI-1.

In patients with LR, a short (< or = 2 years) disease-free interval (DFI) and skin involvement of LR were associated with poor postrelapse distant metastasis-free survival (PR-DMFS, P = .001, both) and postrelapse overall survival (PR-OS; P < .0001 and P < .0002, respectively). The primary tumor levels of uPA and PAI-1 were elevated for patients with a short DFI (P < .01), but such a relation was not observed for patients with skin involvement. In univariate analyses, high levels of uPA and PAI-1 in the primary tumor were associated with poor PR-OS (P = .038 and P = .040, respectively) but not PR-DMFS. In Cox multivariate analyses for PR-DMFS and PR-OS, only a short DFI and skin involvement of the LR were independently associated with a poor clinical outcome.

In patients treated with breast-conserving therapy who had LR as a first event, a short DFI and skin involvement were strong indicators for poor PR-DMFS and PR-OS. The proteases studied did not contribute significantly to the final multivariate model.