Fig 4. Axial T1-weighted contrast-enhanced MR image of the nasopharynx in a patient with suspected NPC (group 2) where MR imaging incorrectly diagnosed cancer that was later shown by biopsy to be lymphoid hyperplasia. A, Section at the level of the fossa of Rosenmuller shows mucosal abnormality in the fossa bilaterally (arrows), giving the false-positive result on MR imaging for cancer.

B, Section at the level of the roof shows the "striped" appearance of normal lymphoid tissue in the adenoids (arrows).