Multimodal ultrasonography features of the extramedullary plasmacytomas in multiple myeloma: a retrospective case series study

Aims: To investigate the multimodal ultrasonography (US) features of extramedullary plasmacytomas (EMPs) in patients with multiple myeloma (MM).Material and methods: Nine patients with MM who were diagnosed EMPs and underwent multimodal ultrasonography were enrolled in this study. Clinical information and multimodal US results were retrospectively analyzed. The multimodal US with a standardized sonographic protocol including US, color Doppler flow imaging (CDFI), microvascular US, ultrasound elastography (UE) and contrast-enhanced ultrasound (CEUS) was performed on the enrolled patients.Results: This study included both males (4 of 9) and females (5 of 9), with ages ranging from 48 to 72 years. The nine lesions were located in the skin/muscle (7 of 9) and pleura (2 of 9). On US images, all lesions showed inhomogeneous solid hypoechogenicity without calcification. Vascularity was abundant (hypervascularization). CEUS images confirmed this vascular pattern (9 of 9) and presented hyperenhancement with enlarged range. On elastographic images, the lesions presented with high elastic score (3-4).Conclusions: An inhomogeneous hypoechoic soft tissue or visceral mass occurring in MM with increased vascularity, low elasticity, and hyperenhancement along with enlarged range can indicate the diagnosis of EMP on multimodal US images.