Differentiation of myxoid liposarcoma by magnetic resonance imaging: a histopathologic correlation

Abstract

Tumor components with contrast-enhancing non-fatty, non-myxoid imaging features were predominantly found in high-grade myxoid liposarcomas, which may histologically resemble round cell clusters.

Relationship between diffusion parameters derived from intravoxel incoherent motion MRI and perfusion measured by dynamic contrast‐enhanced MRI of soft tissue tumors

“…It has been reported that both benign and malignant STTs may have a myxoid tumor matrix, which is characterized by abundant free water in the extracellular spaces, significantly increasing the ADC values (5,(26)(27)(28)(29). For these reasons, we decided to compare IVIM DWI and DCE MRI parameters among patients with and without myxoid tumors; consistent with previous studies (27,35), the differences in ADC values were strongly significant, as were the differences in D values.…”

“…Our IVIM DWI and DCE MRI results confirmed the wide heterogeneity in both diffusion and perfusion parameters of STTs. According to previous studies , very high ADC and D values were found for myxoid lesions as a result of the presence of abundant free water in the extracellular spaces of the tumor matrix. The lowest ADC and D values were found primarily for malignant tumors, such as undifferentiated pleomorphic sarcomas and malignant schwannomas, which are characterized by increased nIAUGC and MSI.…”

“…a villonodular synovitis, an angiolipoma and a myositis ossificans), as documented by DCE MRI parameters (see Table S1 for details). However, the group of myxoid tumors included a majority of lesions with abundant myxoid matrix, in general almost completely avascular, as well as myxomas (two cases) and low‐grade myxoid liposarcomas (three cases), which may have contributed to decrease the perfusion‐related parameters of this patient group .…”

Current Concepts in Non-Gastrointestinal Stromal Tumor Soft Tissue Sarcomas: A Primer for Radiologists

“…The 2013 WHO classification accordingly discarded the term ‘round cell liposarcoma’ from the classification. These tumors are now considered to represent high-grade myxoid liposarcoma, with the prognosis worsening with increasing round cell component (> 5%) (192526). …”

“…Macroscopic fat is the clincher if observed on imaging, but may constitute < 10% of tumor volume and may be difficult to visualize on imaging (192527). Visualization of a non-fatty non-myxoid enhancing component may correspond to the round cell component, if present, and should be targeted for biopsy (2526). Given the presence of these various components, visualization of a true ‘cyst mimic’ (a tumor which could be misdiagnosed as a cyst without administering intravenous contrast) is uncommon (20).…”