Tumour extent and T stage of nasopharyngeal carcinoma: a comparison of magnetic resonance imaging and computed tomographic findings.

ABSTRACT

PURPOSE: To compare magnetic resonance imaging (MRI) and computed tomography (CT) in defining the T stage and full tumour extent of nasopharyngeal carcinoma. PATIENTS AND METHODS: Forty-eight patients with pathologically proven nasopharyngeal carcinoma underwent MRI and CT examinations within 2 weeks of each other. Contrast medium was used in both examinations. The T stage and full tumour extent according to MRI and CT were compared. RESULTS: In 32 patients MRI and CT findings agreed completely. MRI findings resulted in assignment of a higher stage than CT findings in another 8 patients. In the remaining 8 patients MRI showed wider tumour spread than CT, although there was no discordance in the T stage assigned. CONCLUSION: When compared with CT in defining the full tumour extent and assigning the T stage in 48 patients with nasopharyngeal carcinoma, MRI showed more extensive disease in 16 patients, including 8 in whom the T stage was revised upward. Therapy was altered as a result of the MRI findings.