Title: A Clinicopathological Study of Salivary Gland Lesions and Immunohistochemical Expression of Bcl2 in Benign and Malignant Salivary Gland Neoplasms
Authors: Yashika Sharma, Nidhi Verma, Kavita Tiwari, Vijay Kumar, Anamika Thakur
DOI: https://dx.doi.org/10.18535/jmscr/v12i01.12
Abstract
Introduction
Salivary glands neoplasms (SGNs) are rare tumors and comprise approximately 3-10% of the neoplasms of the head and neck region and 1% of the neoplasms of the whole body(1). Annual global incidence of SGNs is between 0.4 to 13.5 cases per 1, 00,000 individuals(2). Among these, malignant salivary gland neoplasms (MSGNs) are 0.40 to 0.65 per 1, 00,000 cases(3). MSGNs are 0.3% of all malignancies(4). Early diagnosis of MSGNs play an important role in better management of these tumors(5). Fine-needle aspiration cytology (FNAC) is used as a screening and early diagnostic tool in SGNs however its role is limited(6).
Accurate diagnosis depends upon the histological evaluation of SGNs.
Although haematoxylin-eosin (H&E) staining is still the gold standard for diagnosing the SGNs yet its role is limited in certain cases. Immunohistochemistry (IHC) can enhance the accuracy and may be a helpful tool when there is a need to investigate cell type and differentiation status, cell proliferation, and tumor protein expression that cannot be assessed by routine histological examination alone. There is also a need to investigate new biomarkers that can be useful in the diagnosis and grading of malignant salivary gland neoplasm(7). Bcl-2 (B-cell lymphoma) oncoprotein is a useful marker for investigation in SGNs. Bcl-2 gene family consists of different regulators involved in apoptosis. It is considered as anti-apoptotic protein and plays a key role in preventing programmed cell death by favouring prolonged survival in normal and neoplastic cells. Increased expression has been seen in a number of tumors and is related to resistance to conventional cancer management(8). It’s expression has been studied in oral epithelial dysplasia, oral sub mucous fibrosis and oral squamous cell carcinoma and its expression showed increasing with the severity of dysplasia and decreased expression in differentiation of oral carcinoma. The present study was planned to determine the expression of Bcl-2 proteins in benign and malignant salivary gland neoplasms and to determine association of Bcl-2 expression with different grades of malignant salivary gland neoplasms.
