Evaluation of MMP2 and Caspase-3 expression in 107 cases of papillary thyroid carcinoma and its association with prognostic factors.

Papillary thyroid carcinoma (PTC), including its variants and widely varying behavior, constitutes about 80% of all thyroid malignancies. Increased knowledge regarding molecular alterations has led to attempts to identify diagnostic or prognostic factors for a reliable preoperative approach to the classification of patients according to risk of recurrence. In this study, 107 cases of PTC with known histological properties, including vascular or capsular invasion, were assessed for expression of MMP2 and Caspase-3 using immunohistochemistry. Considering 10% as a cutoff to discriminate cases with invasive behavior from the non-invasive group, there was no relationship between expression of MMP2 or Caspase-3 in tumor cells and the presence of capsular invasion (p=0.45 and 0.64, respectively), as well as for the expression of Caspase-3 and vascular invasion (p=0.43). In case of MMP2, a borderline correlation was found between the positive reaction of tumor cells with the presence of vascular invasion (p=0.05). So the evaluation of MMP2 in thyroid PTC appears to be of some benefit to the prediction of tumor behavior while Caspase-3 as a marker of prediction seems to be of no use.