Circulating gelatinases are not prognostic of treatment response and survival in locally advanced rectal cancer patients undergoing preoperative chemoradiotherapy.

<bold>Purpose: </bold>To investigate whether the serum levels of matrix metalloproteinases (MMPs) are predictive on treatment response and survival in locally advanced rectal cancer (LARC) patients undergoing preoperative chemoradiotherapy.<bold>Patients and Methods: </bold>Serum MMP-2 and MMP-9 was analyzed by enzyme-linked immunosorbent assay and obtained before, midway, and 1-month after the end of preoperative radiotherapy treatment. The prognostic significance of serum MMP-2 and MMP-9 levels and their association with other pathological findings for LARC patients were evaluated.<bold>Results: </bold>Serum levels of MMP-2 or MMP-9 were found to decrease with increasing clinical stage and negative correlation was statistically significant (P < 0.05). There was no statistically significant difference in tumor response and survival between the low and high MMP-2 and MMP-9 groups. MMP-2 and MMP-9 were not correlated with local-regional recurrence.<bold>Conclusions: </bold>We propose that serum levels of MMP-2 and MMP-9 are not predictive on treatment response and survival in LARC patients. [ABSTRACT FROM AUTHOR]