Differentiation of pleomorphic adenoma and Warthin's tumour of the salivary gland: is long-to-short diameter ratio a useful parameter?

Vascular Pattern Analysis on Microvascular Sonography for Differentiation of Pleomorphic Adenomas and Warthin Tumors of Salivary Glands

“…In our study, the size of tumors (long and short diameters) was not significantly different between the tumor types, consistent with what has been reported previously . A very recent study, however, reported that the ratio of the long diameter to short diameter of tumors was useful for differentiating between pleomorphic adenomas and Warthin tumors, whereas our results showed that the ratio was not different between the groups (1.5 for pleomorphic adenomas and 1.6 for Warthin tumors).…”

“…We found no grayscale sonographic features of the tumors that were significantly different between the groups. The border characteristics of the tumors were not useful in distinguishing between the tumors in several earlier studies . In our study, most tumors showed well‐defined borders, and only 3 patients showed partially poorly defined borders.…”

“…Sonography is an effective method for detecting and localizing salivary gland tumors. However, even differentiating between the two most common salivary gland tumors, pleomorphic adenomas and Warthin tumors, is challenging on sonography …”

“…Pleomorphic adenomas are associated with a 2% to 25% risk of malignant transformation over time, and recurrence rates have been shown to be higher in patients who undergo enucleation; therefore at least a partial parotidectomy should be performed . In contrast, Warthin tumors usually do not recur, and malignant transformation has not been observed . Furthermore, patients who cannot undergo invasive procedures can avoid those processes by precise preprocedural or preoperative imaging.…”

“…Many previous studies have focused on differential diagnosis between pleomorphic adenomas and Warthin tumors using sonography. However, because of the substantial overlap in sonographic features between these tumors, including vascular features on Doppler sonography, results were inconsistent among studies …”