Conventional MRI findings for predicting submandibular pleomorphic adenoma

Area of Science:

• Radiology
• Oncology
• Head and Neck Surgery

Background:

• Pleomorphic adenomas are the most common benign submandibular gland tumors, yet their imaging characteristics are not widely documented.
• This study addresses the need for detailed imaging feature analysis of these tumors.

Purpose of the Study:

• To evaluate conventional magnetic resonance imaging (MRI) findings for the accurate prediction of submandibular pleomorphic adenoma.
• To identify key imaging signs that differentiate pleomorphic adenomas from other submandibular tumors.

Main Methods:

• Retrospective review of MRI studies for 42 pleomorphic adenomas and 28 other submandibular tumors.
• Assessment of MR images for three specific signs: T2-weighted hyperintensity, well-defined margins, and ipsilateral normal gland compression.

Main Results:

• T2-weighted hyperintensity (97.6% sensitivity) and well-defined margins (95.2% sensitivity) are common but non-specific findings.
• Crescent-shaped compression of the normal gland demonstrated high specificity (100%) but low sensitivity (23.8%).
• Combining T2 hyperintensity and well-defined margins yielded 90.9% accuracy for submandibular pleomorphic adenoma diagnosis.

Conclusions:

• Submandibular pleomorphic adenomas typically exhibit T2-weighted hyperintensity and well-defined margins on MRI.
• Crescent-shaped compression of the adjacent normal submandibular gland is a highly specific imaging sign for pleomorphic adenoma.
• Conventional MRI findings, particularly when combined, can effectively aid in the diagnosis of submandibular pleomorphic adenomas.