A comparative study of tissue inhibitor of metalloproteinases-1 levels in plasma and tumour tissue from patients with primary breast cancer and in plasma from patients with metastatic breast cancer.

OBJECTIVE

Tissue inhibitor of metalloproteinases-1 (TIMP-1) has been investigated as a potential tumour marker in breast cancer. Here we investigated the correlation between TIMP-1 in tumour tissue and plasma to evaluate whether TIMP-1 in plasma is actually a surrogate marker for TIMP-1 in primary tumours. Furthermore, we assessed whether increased TIMP-1 levels in plasma could be indicative of tumour progression in patients with advanced breast cancer.

METHODS

Tumour tissue and preoperatively collected plasma samples from 96 primary breast cancer patients were included together with plasma samples from 46 patients with advanced disease. TIMP-1 levels were measured by ELISA.

RESULTS

TIMP-1 levels in plasma (median 81.5 ng/ml, range 41.9-174.9) and tumour tissue (median 25.4 ng/mg of total protein, range 0-110.2) from primary breast cancer patients were not correlated (r = 0.05, p = 0.6). Plasma levels of TIMP-1 in primary breast cancer patients were significantly lower than levels in patients with advanced disease (median 108.7 ng/ml, range 59.7-560.7; p < 0.0001).

CONCLUSIONS

Our findings suggest that TIMP-1 release into the blood might be controlled by an active mechanism. They also point to plasma TIMP-1 as a potential marker for predicting tumour progression and for monitoring tumour burden in metastatic breast cancer patients.