Characteristics of 18F-FDG PET/CT in patients with Kimura's disease from China.

Background: 'Kimura's disease (KD) is a rare chronic inflammatory disorder of unknown etiology and is difficult to diagnose due to poor clinical presentation and imaging features. Few studies on characteristics of ¹⁸F-FDG PET/CT of KD have been reported. This study aimed to observe the reliable characteristics and usefulness of ¹⁸F-FDG PET/CT for the evaluation of consecutive patients with KD.

Methods: The clinical data and ¹⁸F-FDG PET/CT imaging findings of 8 patients with pathologically confirmed KD were reviewed retrospectively.¹⁸F-FDG PET/CT images were evaluated visually and semiquantitatively by measuring the maximum standardized uptake value (SUV_max). The correlations between clinical data and ¹⁸F-FDG PET/CT features were analyzed by simple linear regression.

Results: This study included 7 males and one female ranging in age from 17 to 79 years. The longest diameter of lesions ranged from 0.8 cm to 4.8 cm, and regional or generalized lymphadenopathy was found in all 8 patients with eosinophilia, while subcutaneous masses and salivary gland involvement concurrently were found in 4 patients. ¹⁸F-FDG PET/CT revealed that these involved lesions had high ¹⁸F-FDG uptake with SUV_max > 2.5 (2.6 to 6.3). Moreover, the margin of the lesions was well defined in 6 cases and ill defined in 2 cases, and homogeneous density and ¹⁸F-FDG uptake were both found in all these lesions. There was negative correlation between eosinophils and SUV_max (R² = 0.538).

Conclusions: Kimura's disease should be considered when ¹⁸F-FDG PET/CT is characterized by homogeneous lesions of regional or generalized lymphadenopathy, accompanied with subcutaneous masses and salivary gland involvement concurrently, especially in patients with eosinophilia.