Ultrasonography-guided core-needle biopsy of parotid gland masses.

BACKGROUND AND PURPOSE An accurate diagnosis of a parotid gland mass is essential for adequate management. We determined the clinical efficacy of USCNB in diagnosing parotid gland masses by using cutting needles of different bores. METHODS We reviewed records for 40 benign and 13 malignant parotid lesions. USCNB was performed by using 14-20-gauge needles (mean, 16.6 gauge) with one to five (mean, 2.43) passes and a 15-mm throw or specimen notch. Final diagnoses were established on the basis of surgicopathologic results in 31 cases, and on the basis of histopathologic analysis of biopsy specimens, clinical data, and/or imaging studies in 22, with a follow-up of 12.2-77.5 months (mean, 33.6 months). RESULTS Compared with surgicopathology, USCNB had a sensitivity of 83%, a specificity of 100%, and an accuracy of 97% in providing specific tissue diagnoses and in differentiating malignant from benign masses. Its positive and negative predictive values were 100% and 96%, respectively, in diagnosing malignancy. One patient (2%) had a local hematoma without sequela after surgical removal of a Warthin tumor. Core biopsy results were completely concordant with surgical findings in 30 (97%) of 31 cases. CONCLUSION USCNB is a safe and efficient diagnostic procedure with an accuracy of 97% in the pathologic diagnosis of parotid masses. It can be performed in an outpatient clinic and enables specific tissue diagnosis to obviate intraoperative frozen biopsy and unnecessary surgery. An 18-gauge needle is sufficient for accurate and specific tissue diagnosis of parotid masses.