Contrast‐enhanced ultrasonography for the differential diagnosis of pleomorphic adenomas and Warthin tumors in salivary glands

OBJECTIVE: Pleomorphic adenomas have risks of malignant transformation and post operate recurrence. Therefor it is important that diagnosing pleomorphic adenomas or Warthin tumors before an operation. We evaluated the usefulness of contrast‐enhanced ultrasonography (CEUS) with Sonazoid for making differential diagnoses between pleomorphic adenomas and Warthin tumors. METHODS: CEUS was performed the day before surgery in 39 patients. We compared the time‐intensity curve and capillary density rate of 14 pleomorphic adenomas and 13 Warthin tumors. RESULTS: Pleomorphic adenomas demonstrated a significantly longer time to peak intensity and lower maximum curve gradient of wash‐in than Warthin tumors. The capillary density rate of Warthin tumors tended to be greater than that of pleomorphic adenomas. CONCLUSIONS: CEUS and capillary density rate analysis using Sonazoid is helpful for the differential diagnosis of pleomorphic adenomas and Warthin tumors. LEVEL OF EVIDENCE: 3b.