MRI characteristics associated with high-grade myxoid liposarcoma. Issue 7 (July 2017)

• Record Type: Journal Article
• Authors: Gimber, L.H.; Montgomery, E.A.; Morris, C.D.; Krupinski, E.A.; Fayad, L.M.
• Is Part Of: Clinical radiology. Volume 72:Issue 7(2017)
• Page Start: 613.e1
• Page End: 613.e6
• Publication Date: 2017-07
• Subjects: Medical radiology -- Periodicals; Radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiology -- Periodicals; Societies, Medical -- Periodicals; Medical radiology; Radiotherapy; Electronic journals; Periodicals; 616.0757
• DOI: 10.1016/j.crad.2017.01.016
• Languages: English
• ISSNs: 0009-9260

Abstract

Abstract : Aim: To identify magnetic resonance imaging (MRI) features differentiating high-grade (>5% round-cell component) from low-grade myxoid liposarcomas (LPS) (≤5% round-cell component). Materials and methods: Informed consent was waived. Patients with myxoid LPS and MRI before biopsy, neoadjuvant therapy, and surgery were included retrospectively. High-grade components were recorded from histological specimens by a pathologist (24 years of experience). Images were evaluated by a senior radiologist (>12 years of experience) for tumour size, location, tissue layer, and MRI features (signal intensity, heterogeneity, margin, and perilesional characteristics). Descriptive statistics, Fisher's exact test to identify associations with a round-cell component, and multivariate logistic regression to identify independent predictors of high-grade tumours were used. Results: Thirty-one patients (16 women [mean 51.1 years; range 19 – 79 years] and 15 men [mean 45.5 years; range 18–95 years]) with myxoid LPS (23 low-grade, eight high-grade) were included. All high-grade lesions had lipid signal, a peritumoural capsule and peritumoural contrast enhancement, and more commonly exhibited heterogeneous signal; however, the average size of ≥10 cm was the strongest independent indicator of high-grade status (odds ratio [OR], 14.6; 95% confidence interval [CI]: 1.6, 131). Conclusion: Size ≥10 cm is most strongly associated with high-grade myxoid LPS (round-cell component >5%). Other features possibly differentiating high-grade from low-grade status include lesion margin, lipid signal, and perilesional characteristics. Highlights: High-grade myxoid liposarcomas contain >5% hypercellular round cell component. High-grade MR findings correspond to unfavorable outcomes and dictate treatment. We evaluated MR features which may differentiate high grade from low-grade lesions. Size ≥10 cm is most strongly associated with high-grade myxoid liposarcomas. Lipid, margin, and perilesional characteristics may also be distinguishing features.