Endoscopic Transoral Resection of Parapharyngeal Pleomorphic Adenoma with Active Myoepithelial Proliferation: A Case Report and Literature Review.

Parapharyngeal space (PPS) tumors are relatively rare, accounting for 0.5% to 1% of all head and neck tumors. Among these, pleomorphic adenoma is the most common benign subtype, representing 34% of all PPS tumors. The core therapeutic principle for this lesion is complete tumor resection to reduce the risk of recurrence. Traditional surgical approaches include transcervical and transoral routes. This study presents a case of pleomorphic adenoma located in the parapharyngeal space with extension to the deep lobe of the parotid gland, which was successfully resected by endoscopic-assisted transoral plasma surgery without robotic assistance. This case provides a valuable clinical reference for the minimally invasive management of similar lesions.