The accuracy of fine needle aspiration cytology in the clinical diagnosis of minor salivary gland tumours

The objective of this study was to investigate the accuracy of fine needle aspiration cytology (FNAC) and biopsy for the clinical diagnosis of minor salivary gland tumours (MSGTs). This retrospective study of 32 MSGT cases was conducted over a 5-year period. Clinical features including age, sex, and location of the tumour were obtained from the patient clinical records. All cases were also assessed histologically according to the 2017 World Health Organization Classification of Head and Neck Tumours. The results of FNAC and biopsy were correlated with those of histopathology, and their sensitivity, specificity, and diagnostic efficacy were calculated using histopathology as the gold standard. Eighteen malignant MSGTs (56.3%) and 14 benign MSGTs (43.8%) were diagnosed by pathological diagnosis. The most common malignant tumour was mucoepidermoid carcinoma (seven cases, 38.9%). Most benign cases were pleomorphic adenomas (13 cases, 92.9%). FNAC was performed for 23 cases and biopsy for 13 cases. The sensitivity and specificity of FNAC were 66.7% and 91.0%, respectively, while those of biopsy were 90.0% and 100.0%, respectively. Although FNAC is a minimally invasive and cost-effective procedure, it is less accurate than biopsy in the assessment of MSGTs. Repeated FNAC or biopsy should be considered in negative and unsatisfactory FNAC cases.