IMMUNOHISTOCHEMICAL VALIDATION OF INSULIN-LIKE GROWTH FACTOR II mRNA-BINDING PROTEIN 3 (IMP3) AS A DIAGNOSTIC MARKER IN SALIVARY GLAND TUMORS

Introduction: Salivary gland tumors (SGTs) are infrequent tumours accounting for 2-6.5% of all head and neck tumors. They show various clinical behaviours and different histological patterns resulting in a diagnostic dilemma. Insulin like growth factor II RNA binding protein 3 (IMP3) is an oncofetal protein that plays an important role in tumor invasion and metastases. Several studies proved the prognostic role of IMP3 in different human cancers. However, its role in SGTs still needs to be confirmed. Objectives: To evaluate IMP3 immunoexpression in benign and malignant SGTs. Material and Methods: IMP3 expression was measured in 44 SGT cases (20 benign and 24 malignant) and 10 normal salivary gland tissues (NSGT).   Immunohistochemical (IHC) staining was carried out by the Labeled Strept-Avidin Biotin complex method (LSAB).  Results: IMP3 expression was detected in NSGT as well as benign and malignant SGTs with different intensities.  The Lowest expression levels were detected in NSGT, while the highest ones were detected in Malignant SGTs. Conclusion: IMP3 could be used as a diagnostic marker in SGTs.