Purpose: The aim of this study was to determine whether serum matrix metalloproteinase (MMP) -2 and MMP-9 levels could predict overall and disease-free survival in primary node-positive breast cancer.
Experimental design: MMP-2 and MMP-9 levels were quantitatively measured in serum after surgery from 133 patients with primary node-positive breast cancer using enzyme-linked immunoassays. All of the patients received adjuvant therapy, postmenopausal endocrine treatment (tamoxifen or toremifen for 3 years) and premenopausal six cycles of CMF chemotherapy. The follow-up time for all of the patients was 5 years.
Results: Overall survival (OS) and disease-free survival (DFS) rates were better among patients with low MMP-2 levels than in patients with high levels (OS, 91% versus 75%, P = 0.020; DFS, 82% versus 58%, P = 0.005). The appearance of bone and visceral metastases was also significantly lower in patients with low serum MMP-2 levels (bone metastases, 10% versus 23%, P = 0.050; visceral metastases, 12% versus 34%, P = 0.018). The prognostic value of MMP-2 levels was most pronounced among a subgroup of estrogen receptor-positive patients (OS, 96% versus 78%, P = 0.052; DFS, 85% versus 58%, P = 0.014), whereas no significant difference was found among estrogen receptor-negative patients (OS, 73% versus 69%, P = 0.25; DFS, 73% versus 63%, P = 0.32). In multivariate analysis, MMP-2 level together with nodal status (NS), progesterone receptor (PgR), and tumor size (T) remained independent predictors for DFS (NS, P = 0.002; PgR, P = 0.004; T, P = 0.023; MMP2, P = 0.039) and OS (NS, P = 0.0002; PgR, P = 0.004; T, P = 0.004; MMP2, P = 0.032). MMP-9 levels did not correlate with survival.
Conclusions: The results suggest that serum postoperative MMP-2 level is a predictor of DFS and OS, and could help to stratify breast cancer patients with primary node-positive disease into low- and high-risk groups.