Values of fine-needle aspiration cytology of parotid gland tumors: A review of 996 cases at a single institution

Background We evaluated the diagnostic accuracy of fine-needle aspiration cytology (FNAC) in a large series of benign and malignant parotid tumors. Methods The FNAC diagnosis of 821 benign and 175 malignant parotid tumors managed at our department between 1999 and 2017 was correlated with the final histology. Results FNAC made a correct histopathological diagnosis in 72% of the benign parotid tumors; however, FNAC provided a correct grade in only 34% of the malignant tumors. FNAC correctly identified the histology of 94% of pleomorphic adenomas subsequently confirmed by histopathological examination. The sensitivity, specificity, and diagnostic accuracy of FNAC for detecting malignancy were 82.3%, 98.7%, and 95.9%, respectively. Conclusion FNAC generally provided the correct histological diagnosis for benign tumors. However, the histological evaluation and grading of malignant tumors were poor. Although FNAC showed good sensitivity, specificity, and accuracy, its sensitivity decreased when nondiagnostic cases were included in the analysis.