Proliferation PET/CT Imaging of Salivary Gland Tumor

Salivary gland tumors are rare neoplasms which vary in terms of origin and malignant potential. 2-[18F]-fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET) has limited ability to differentiate between different types of salivary gland tumors because both Warthin’s tumors and pleomorphic adenomas usually show increased FDG uptake, with no statistically significant difference in standardized uptake value (SUV) compared with malignant salivary gland tumors. Here, we discuss 4′-[methyl-11C]-thiothymidine (4DST) PET, which provides cell proliferation imaging capable of demonstrating intense uptake in parotid carcinoma and Warthin’s tumor, but no uptake in parotid pleomorphic adenoma. This is the first report of the potential of proliferation PET/ computed tomography (CT) imaging for characterizing salivary gland tumors based on the molecular pathogenesis of the tumor.

Histopathological spectrum and outcome of surgery for salivary gland tumors presented in tertiary care hospital of Pakistan.

Objective: This study is aimed to know the histopathological spectrum and outcome of surgery for salivary gland tumors presented in a tertiary care hospital of Pakistan. Study Design: Retrospective study. Setting: Tertiary Care Hospital of Pakistan. Period: July 2018 to June 2020. Material & Methods: After approval from Institutional Review Board. Total 73 patients were selected with preoperative diagnosis of salivary gland tumors with consecutive non probability sampling. All surgical procedures were done by specialist general surgeons who had experience of more than 10 years of head and neck surgery. Results: Male to female ratio was 2:1 with mean age of patients was 46 years. Among males 29 (59.1%) were benign salivary gland tumors while 20 (40.81%) were malignant salivary gland tumors. Among females 13 (54.16%) were benign and 11 (45.83%) were malignant salivary gland tumors Most common benign tumor was pleomorphic adenoma 32 (43.8%) while mucoepidermoid carcinoma was most common malignant tumor 17 (23.28%). Only 9 (12.32%) patients experienced nerve paresis. Conclusion: Male preponderance, a relatively younger age at presentation and single predominant benign tumor (pleomorphic adenoma) were the significant findings. Majority of them were found in parotid gland and found to be benign in nature. Majority of them were found in parotid gland and found to be benign in nature. Although fine needle aspiration cytology and magnetic resonance imaging provide some useful information about the nature of tumor but most of them will acquire a surgical excision in order to find the definitive diagnosis.

Immunohistochemical Expression of BCL-2 in Malignant Salivary Gland Tumors

Background: Malignant salivary gland tumors (MSGTs) consist of a heterogeneous group of neoplasms with complex clinicopathological features and biological behaviors. The purpose of this study was to determine the expression of Bcl-2 antiapoptotic protein in mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ADCC), acinic cell carcinoma (ACC) and polymorphous low-grade adenocarcinoma (PLGA) of salivary glands and to find out its association with different grades of these tumors. Material and Methods: This descriptive study included 55 cases of MSGTs. Tissue sections were stained with routine hematoxylin and eosin stain as well as Bcl-2 immunostain. MSGTs were graded as low grade (Low grade MEC, ACC, PLGA, and tubular pattern of ADCC), intermediate grade (cribriform pattern of ADCC, and intermediate grade of MEC) and high grade (high grade of MEC and solid pattern of ADCC) tumors on H&E sections. Bcl-2 expression was scored as ‘negative’ (<5% of neoplastic cells), ‘1’ (5-19% of neoplastic cells), ‘2’ (20-49% of neoplastic cells), and ‘3’ (>50% of neoplastic cells), respectively. Results: MSGTs most commonly involved the parotid gland (52.7%), while ADCC (40%) and MEC (38.2%) were the most common tumors. Expression of Bcl-2 was strongly positive in 56.4% cases of MSGTs which included ADCC (71%), MEC (19.4%) and ACC (9.7%), respectively. A significant association was found between Bcl-2 staining and types of MSGTs i.e., MEC, ADCC, ACC (P = .001) as well as between Bcl-2 staining and grades of MSGTs (P = .013). Conclusions: Bcl-2 protein is expressed in malignant salivary gland tumors. Its expression maybe helpful in grading small biopsies, predicting behavior, and planning targeted therapy of MSGTs.