The relative value of fine-needle aspiration and imaging in the preoperative evaluation of parotid masses.

Abstract

To establish the sensitivity, specificity, and accuracy of imaging and fine-needle aspiration (FNA), alone or in combination, in distinguishing benign from malignant histologic findings for parotid lesions. Retrospective blinded review of preoperative imaging and FNA studies of parotid masses and comparison with histologic findings after excision. Forty-eight patients were identified (13 with CT, 35 with MRI); 23 (48%) of the lesions were malignant, 25 (52%) were benign. MRI, CT, and FNA misclassified 17%, 46%, and 21% of the lesions, respectively. The sensitivity/specificity/accuracy of these tests for detecting malignant lesions were as follows: MRI (88%,77%,83%), CT (100%,42%, 69%), and FNA (83%,86%,85%) and were not significantly different. Combinations of imaging and FNA were not significantly better in detecting malignancy. Imaging and FNA are comparable in their ability to correctly identify malignant parotid lesions preoperatively. Combining these two modalities yields no advantage in terms of specificity, sensitivity, or accuracy of a malignant diagnosis.