Accuracy of frozen section in the evaluation of salivary tumors.

The records of 333 patients who underwent surgery were reviewed to document the accuracy of frozen section in the evaluation of salivary gland tumors. Frozen sections were obtained in 310 patients. The final pathologic diagnoses included 210 benign tumors and 45 malignancies. The sensitivity for the detection of malignancy was 69%, and the specificity was 96%. The specific accuracy to correctly identify the type of malignancy present was only 51%. In four patients, a false-positive diagnosis of malignancy was made. Frozen section was much more accurate in the evaluation of benign salivary tumors. Forty-three of 45 Warthin's tumors were correctly identified by frozen section. Two tumors thought to be Warthin's tumors on frozen section proved to be low-grade mucoepidermoid carcinomas. One tumor reported to be a benign mixed tumor was actually a malignant mixed tumor. In this series of patients, frozen section proved to be no more accurate in the evaluation of salivary tumors than what has been reported in the literature for fine-needle aspiration biopsy.