Role of FNAC in diagnosis of parotid lesions

Abstract

BackgroundSalivary gland masses are considered challenging for diagnosis regarding its origin and whether benign or malignant. Unique features of FNAC as a safe and easy diagnostic procedure with little discomfort to the patient made it a favorable primary diagnostic tool. Information regarding the nature of parotid lesions whether being benign or malignant is the main objective of FNAC. We have done a restrospective study for FNAC for parotid masses performed in John Hunter hospital (Newcastle, NSW, Australia) along the peroid from 2014-2018. Histopathological correlation was done in 74 cases to test the accuracy of FNAC in diagnosis of parotid lesions.ResultsOf the total 74 FNAC done for parotid lesions in which a histopathological correlation was done, we get 46 (62.2%) benign lesions (37 neoplastic and 9 non-neoplastic) while 28 (37.8%) were malignant tumor. Pleomorphic adenoma was the most common in benign tumor side (45.7%) while SCC is the most common in malignant group (53.6%). Compatibility between FNAC and histological diagnosis was found in 74% (55/74), of which 78.3% in benign lesions (36/46) and in 68% of malignant lesions (19/28). FNA cytology was true positive in 21/74 cases (28.4%) and true negative in 41/74 (55.4%) cases. We have 5 (6.8%) false-negative and 7 (9.5%) false-positive results. As a result, we get sensitivity of 81%, specificity of 85%, and accuracy of 84%.ConclusionThe role of FNAC in diagnosis of primary salivary gland pathology is considered with some debate about sensitivity/specificity; however, sometimes it should be repeated or correlated with clinical/histopathological confirmation.