Multimode Ultrasound Features in Skeletal Muscle Lymphoma: A Retrospective Observational Study.

Abstract

Objectives: This study aimed to evaluate the ultrasound findings in skeletal muscle lymphoma and investigate the correlations between ultrasound findings and histopathological characteristics.

Methods: Ultrasonographic images with skeletal muscle lymphoma obtained between June 2014 and June 2024 were retrospectively reviewed. The ultrasonographic examinations comprised gray-scale (n = 35), color-Doppler (n = 35), contrast-enhanced (n = 5), and elastography imaging (n = 5). Biopsy samples underwent histopathological analysis to identify the histopathologic basis of the typical ultrasound features. Kappa statistics were used to assess the consistency between ultrasound findings and histopathological features.

Results: The study comprised 35 patients (mean age, 63 years ±15 [standard deviation], 17 men). In gray-scale sonography, 35 lesions (100%) appeared as hypoechoic areas in the muscle with poorly defined margins. Residual myofiber-like echoes were observed in 25 (71.4%) lesions, and a "cobblestone" appearance was noted in 18 (51.4%). In color-Doppler sonography, 10 (28.6%) patients had intact transverse vessels perpendicular to the long axis of the muscle. In contrast-enhanced sonography, 4 out of 5 (80%) lesions showed synchronous high enhancement. Four out of 5 (80%) lesions exhibited high stiffness on elastography imaging. Myofiber-like echoes (κ: 0.800, P < 0.001) and the "cobblestone" appearance (κ: 0.521, P < .017) are consistent with myofibers in pathology.

Conclusion: Skeletal muscle lymphoma demonstrates specific features on multimodal ultrasound.