Matrix metalloproteinase-9 (MMP-9) immunoreactive protein has modest prognostic value in locally advanced breast carcinoma patients treated with an adjuvant antiestrogen therapy.

BACKGROUND

Matrix metalloproteinases (MMPs) are involved with tumour invasion and metastasis. Controversial data exists concerning the prognostic value of MMP-9 in breast carcinoma. We examined, here, whether the MMP-9 immunoreactive protein would correlate with--the prognosis in breast carcinoma treated with hormonal adjuvant therapy.

MATERIALS AND METHODS

The MMP-9 status was determined immunohistochemically from primary tumour specimens in 168 postmenopausal breast cancer patients with a locally advanced (N+) disease treated with antiestrogen for three years after the primary therapy.

RESULTS

A positive immunostaining for MMP-9 was found in 61.3% of 168 primary tumours without any significant correlation to clinical stage, histology or hormone receptor status. MMP-9 immunoreactivity did not correlate with the survival when the entire study population was included in the analysis. There was, however, a compromised disease-free survival in a subgroup of patients presenting with an estrogen receptor-negative and MMP-9-positive tumour. The 5-year disease-free survival was only 37% in those patients, when it was 63% in the patients with a tumour negative for both estrogen receptor and MMP-9.

CONCLUSION

We suggest that the prognostic value of MMP-9 immunoreactivity in the primary tumour is not generally strong in breast carcinoma, but it might correlate with the clinical benefit of an antiestrogen therapy, since MMP-9 positivity seemed to correlate with early recurrence in patients with an estrogen receptor-negative primary tumour.