Familial Nasopharyngeal Carcinoma 6

Imaging in the Diagnosis and Staging of Carcinoma of Nasopharynx 87aabbFig. 8.7. Nasopharyngeal carcinoma with lower cranial neuropathies.(a) Axial contrast-enhanced MR image shows anadvanced nasopharyngeal carcinoma involving the left carotidspace, encircling the internal carotid artery (arrow).(b) Coronal contrast-enhanced T1-weighted image revealsfurther superior spread of the tumor into the left jugularforamen (arrow). Note tumor infiltration of the left occipitalcondyle (asterisk)8.3.2.3Posterior SpreadPosteriorly, NPC may infiltrate the retropharyngealspace and the prevertebral muscles of the perivertebralspace (Fig. 8.8a). In advanced diseases, the vertebraeare destructed with tumor extension into thespinal canal.Fig. 8.8. (a) Axial contrast-enhanced T1-weighted MR imageshows posterior spread of a nasopharyngeal carcinoma,with infiltration of the prevertebral muscles (black arrow).The tumor has also invaded the right carotid space, surroundingthe internal carotid artery (white arrow). (b) Axialcontrast-enhanced T1-weighted MR image more inferiorly atthe level of C3 shows tumor extension into the oropharynx(asterisk)8.3.2.4Inferior SpreadMany NPC show preferential spread inferiorly alongthe submucosal plane, which may not be apparenton clinical inspection or endoscopic examination.Inferior tumor extension into the oropharynx isreadily appreciated on coronal or sagittal MR images.On axial sections, the oropharynx is deemed involvedwhen the tumor is seen inferior to the C1/C2 junction(Fig. 8.8b).