FIGURE 1. A 53-y-old man with NPC 14 mo after intensity-modulated radiation therapy and intracavity brachytherapy. (A) Axial T1-weighted MR image shows an irregular mass (arrow) in the left nasopharynx. (B) ¹⁸F-FDG PET image shows a false-positive finding. Histopathologic findings showed acute and chronic inflammation, and follow-up MRI 4 mo later showed regression of the lesion.