Author(s)

Lemort M, Leurquin M

Patient

male, 32 year(s)

Large tumour of the nasopharynx found after complaints of persistant facial pain

This patient, a woodworker, was referred in our institution for staging of a large rhinopharyngeal tumour discovered after persistent pain following extraction of a right superior molar tooth. A trigeminal neuralgy was already diagnosed. A MR examination is performed using following sequences : T1w SE axial and frontal pre and post Gd DOTA, T2w SE axial. Where is the posterior limit of the lesion ? What about the masticator space ? Is there any intracranial extension ? How do you explain the high signal on the T2w images of the mastoid cells ?

Both the retropharyngeal spaces and the left prevertebral space are involved. The tumour infiltrates the masticator space with a perineural extension around the V3 nerve up to Meckel's cave. The intracranial extension follows a perineural way (V3 --> foramen ovale --> Meckel's cave) and a contiguous way through the sphenoid sinus. The hypersignal in the mastoid cells is caused by middle-ear fluid resulting from Eustachian tube malfunction (probably due to a tumour infiltration of the torus tubarii). Diagnosis was confirmed by biopsy : nasopharyngeal epithelioma (Regaud type). This refers to an undifferenciated nasopharyngeal carcinoma with foci of cells from epithelial origin (ref.1-3). The patient was only partially treated by chemo- and radiotherapy because he was lost of follow-up.