Tumor tissue levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) and survival following adjuvant chemotherapy in pre-menopausal lymph node-positive breast cancer patients (N=525)

Predictive markers are needed to guide planning of adjuvant therapy for patients with breast cancer. We have recently shown that high tumor tissue levels of TIMP-1 are associated with decreased response to chemotherapy in metastatic breast cancer patients (Schrohl et al, Clin Cancer Res, 2006) suggesting that TIMP-1 may be a predictive marker in breast cancer patients. Purpose: This study investigates the association of tumor tissue TIMP-1 levels with response to adjuvant chemotherapy with CMF (cyclophosphamide/methotrexate/5-fluorouracil) or an anthracycline-containing regimen.Patients and Methods: 525 pre-menopausal lymph node-positive patients were included; 324 patients received adjuvant CMF, 99 received an adjuvant anthracycline-containing regimen and 102 had no adjuvant chemotherapy. Total TIMP-1 levels were measured by use of ELISA in cytosolic extracts of frozen primary tumors. Using the untreated patient group as a reference group, we analyzed the benefit of adjuvant CMF and anthracyclines in TIMP-1 high and low patients, respectively. The median TIMP-1 concentration was used to dichotomize patients into high and low TIMP-1 groups. End points were disease-free and overall survival (DFS, OS).Results: The median TIMP-1 level in the total patient group was 12,54 ng/mg of total protein (range, 0 - 112,9 ng/mg). TIMP-1 levels in subgroups according to adjuvant therapy were not significantly different (P=0,20). In a multivariate model including basic clinico-pathological parameters, TIMP-1 low and high patients benefited differentially from adjuvant CMF and anthracyclines when compared to untreated patients. In particular, patients with high tumor levels of TIMP-1 had little benefit from adjuvant anthracyclines. Hazard ratios (HR) and 95% confidence intervals (CI) are given in the table below for the analysis of DFS. A similar pattern was seen in the analyses of OS. In the group treated with CMF, both TIMP-1 low and high patients had significant