Primary Soft-Tissue Lymphomas: MRI Features Help Discriminate From Other Soft-Tissue Tumors

Area of Science:

• Radiology
• Oncology
• Pathology

Background:

• Extra-nodal soft-tissue lymphomas (STLs) are rarely reported on MRI.
• Distinguishing STLs from other soft-tissue tumors (STTs), including sarcomas (STS), is challenging.
• Accurate MRI interpretation could significantly shorten diagnostic timelines.

Purpose of the Study:

• To determine if conventional MRI can differentiate STLs from other STTs.
• To identify MRI characteristics predictive of STLs.
• To evaluate the diagnostic performance of combined MRI features.

Main Methods:

• Retrospective comparison of MRI scans from STL patients and STT patients.
• Analysis of tumor characteristics: size, signal intensity, enhancement patterns, and vascularity.
• Statistical evaluation using uni- and multivariate analyses to identify independent predictors of STL.

Main Results:

• Six MRI features independently predicted STL: intermediate T1 signal, homogeneous enhancement, absence of blood/fibrotic signals, no peritumoral enhancement, and lack of abnormal vasculature.
• A combination of these features achieved 88% sensitivity and 88% specificity for STL detection.
• Specific features like absence of fat signal differentiated STLs from STS, while infiltrative patterns and vessel/nerve encasement distinguished STLs from benign STTs.

Conclusions:

• Conventional MRI can aid in discriminating STLs from other STTs.
• Radiologists can leverage identified MRI features to suggest STL diagnosis.
• This diagnostic support can expedite subsequent histopathological analysis for improved patient management.