Transoral endoscopic ultrasound-guided fine-needle biopsy of a tumor of the parapharyngeal space
The parapharyngeal space is a pyramid-shaped space located between the base of the skull and the hyoid bone, lateral to the naso-oropharynx and medial to the jaw  . It contains the deep lobe of the parotid gland, cranial nerves IX – XII, the internal jugular vein, and the carotid artery . A variety of benign and malignant tumors arise in the parapharyngeal space, the most common being of salivary gland and neurogenic origin . Because of its deep location and concerns about damaging adjacent structures, the parapharyngeal space is difficult to access for biopsy   . Percutaneous, transoral, or transnasal approaches have been used; however, sampling may be challenging even under imaging guidance    . Here we report for the first time a technique of transoral biopsy using a flexible gastrointestinal echoendoscope.
A 41-year-old man with a remote history of mucoepidermoid carcinoma of the left parotid gland presented with a tumor of the right parapharyngeal space ([Fig. 1]). A multidisciplinary tumor board recommended biopsy; however, this was deemed difficult due to the tumor location. After discussion with a gastroenterologist experienced in endoscopic ultrasound (EUS), a decision was made for biopsy under EUS guidance.
With the patient in the left lateral position and under intravenous sedation, a flexible echoendoscope (Olympus GF-UCT180) was introduced in a standard manner into the oral cavity and torqued clockwise. After passing the palatopharyngeal fold, the EUS transducer was gently wedged against the right lateral wall of the pharynx ([Fig. 2]). In this position the tumor was easily identified on the EUS image. Three passes with a 22-gauge Acquire needle (Boston Scientific) were performed ([Fig. 3], [Video 1]). The specimen was processed for histological evaluation, which revealed pleomorphic adenoma ([Fig. 4]). The patient was discharged 48 h later after an uneventful course. The tumor was resected 4 weeks later. Surgical pathology confirmed the diagnosis of pleomorphic adenoma of the deep lobe of the right parotid gland.
Video 1 Successful transoral endoscopic ultrasound-guided biopsy of a tumor of the parapharyngeal space (pleomorphic adenoma of the deep lobe of the parotid gland).
Endoscopy E-Videos is a free access online section, reporting on interesting cases and new techniques in gastroenterological endoscopy. All papers include a high
quality video and all contributions are
freely accessible online.
This section has its own submission
05 August 2020 (online)
© 2020. Thieme. All rights reserved.
Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany
- 1 Lopez F, Suarez C, Vander Poorten V. et al. Contemporary management of primary parapharyngeal space tumors. Head Neck 2019; 41: 522-535
- 2 Riskalla A, Arora A, Vaz F. et al. Novel use of ultrasound-guided endo-cavitary probe to evaluate an impalpable parapharyngeal mass. J Laryngol Otol 2010; 124: 328-329
- 3 Abbas JR, Hamlett KEL, de Carpentier J. Image-guided transnasal endoscopic fine needle aspiration or biopsy of parapharyngeal space tumours. J Laryngol Otol 2018; 132: 1026-1028
- 4 Chen R, Cai Q, Liang F. et al. Oral core-needle biopsy in the diagnosis of malignant parapharyngeal space tumors. Am J Otolaryngol 2019; 40: 233-235
- 5 Arnason T, Hart RD, Taylor SM. et al. Diagnostic accuracy and safety of fine-needle aspiration biopsy of the parapharyngeal space. Diagn Cytopathol 2012; 40: 118-123