Gimber L H, Montgomery E A, Morris C D, Krupinski E A, Fayad L M
Department of Medical Imaging, The University of Arizona, College of Medicine, Banner - University Medical Center, 1501 N Campbell Ave., P.O. Box 245067, Tucson, AZ 85724, USA.
Department of Pathology, The Johns Hopkins University, Weinberg Bldg, Rm. 2242, 401 North Broadway, Baltimore, MD 21231, USA.
Clin Radiol. 2017 Jul;72(7):613.e1-613.e6. doi: 10.1016/j.crad.2017.01.016. Epub 2017 Feb 28.
To identify magnetic resonance imaging (MRI) features differentiating high-grade (>5% round-cell component) from low-grade myxoid liposarcomas (LPS) (≤5% round-cell component).
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.
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).
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.
识别可区分高级别（圆形细胞成分>5%）与低级别黏液样脂肪肉瘤（LPS）（圆形细胞成分≤5%）的磁共振成像（MRI）特征。
无需知情同意。回顾性纳入活检、新辅助治疗及手术前有黏液样LPS及MRI检查的患者。由一名有24年经验的病理学家从组织学标本中记录高级别成分。由一名经验超过12年的资深放射科医生评估图像，以确定肿瘤大小、位置、组织层及MRI特征（信号强度、异质性、边缘及瘤周特征）。采用描述性统计、Fisher精确检验以识别与圆形细胞成分的关联，以及多因素逻辑回归以识别高级别肿瘤的独立预测因素。
纳入31例黏液样LPS患者（16例女性[平均51.1岁；范围19 - 79岁]和15例男性[平均45.5岁；范围18 - 95岁]），其中23例为低级别，8例为高级别。所有高级别病变均有脂质信号、瘤周包膜及瘤周对比增强，且更常表现为信号异质性；然而，≥10 cm的平均大小是高级别状态最强的独立指标（比值比[OR]，14.6；95%置信区间[CI]：1.6，131）。
大小≥10 cm与高级别黏液样LPS（圆形细胞成分>5%）关联最为密切。其他可能区分高级别与低级别状态的特征包括病变边缘、脂质信号及瘤周特征。
