A Comparative Study of Histopathological and Immunohistochemical Expression of MCM3 and MMP-2 in Pleomorphic Adenoma of Major and Minor Salivary Glands

Pleomorphic adenoma (PA) is the most common salivary gland tumor, it shows remarkable degree of morphological diversity and biological controversy. This study was undertaken to compare the proliferation and invasion potentials between major and minor salivary pleomorphic adenoma using MCM3 and MMP-2 biomarkers respectively with correlation to PA subtypes and components. Thirty two paraffin blocks of PA (15 affecting major SGs and 17 were arising in minor SGs) were included in this study and examined in detail for their histomorphological features. Immunohistochemical expression of MCM3 and MMP-2 of the two groups was analyzed. PA of major SGs showed a significantly higher expression of proliferation marker (MCM3) than PA affecting minor SGs (P = 0.01). Although not significant, higher expression of MMP-2 was found in PAs arising in minor SGs (P = 0.09). Moreover, significant invers correlation was observed between MCM3 protein and plasmacytoid cell type in minor gland cases (P = 0.023).