Utility of 18F-FDG uptake in various regions of Waldeyer's ring to differentiate benign from malignant lesions in the midline roof of the nasopharynx.

PURPOSE: Lymphoid hyperplasia is not uncommon in the midline roof of the nasopharynx. Most nasopharyngeal carcinoma patients present with primary tumors in the midline of the nasopharynx. The aim of this study was to evaluate the efficacy of 2-[fluorine-18] fluoro-2-deoxy-D-glucose ((18)F-FDG) PET/computed tomography (CT) to differentiate between benign and malignant lesions in the midline roof of the nasopharynx.

MATERIALS AND

METHODS

The data from the (18)F-FDG PET/CT images of 4846 participants were analyzed. Visual uptake, the lesions' standard uptake values (SUVs), and any abnormalities on the PET/CT images were evaluated.

RESULTS

Sixty-six individuals with benign lesions and 25 with nasopharyngeal carcinoma were included in the analysis. The participants with benign and malignant lesions displayed increased (18)F-FDG uptake (SUV; mean±SD) in the midline roof of the nasopharynx (4.16±1.92 and 6.65±2.81, respectively), with SUVs significantly differing between the two types of lesions (P<0.001). An associated increased (18)F-FDG uptake in Waldeyer's ring and the salivary glands occurred in benign but not in malignant lesions. The ratio of uptake in the midline roof of the nasopharynx and the palatine tonsil in the benign lesions (0.92±0.42) was significantly lower than that in the malignant lesions (1.76±0.93) (P<0.001).

CONCLUSION

The analysis of the intensity and patterns of (18)F-FDG uptake in various regions of Waldeyer's ring provides a feasible modality for the differentiation between benign lesions and malignant nasopharyngeal midline roof lesions.