Encinas Tobajas V M, Almeida González C, Marcilla D, Vallejo M, Cano Rodríguez A, Reina Sánchez de Movellán J I, Morales Pérez J M
Unidad de Gestión Clínica de Radiodiagnóstico, Hospital Universitario Virgen del Rocío, Sevilla, España.
Unidad de Bioestadística, Hospital Universitario Virgen de Valme, Sevilla, España.
Radiologia (Engl Ed). 2021 Mar 12. doi: 10.1016/j.rx.2021.01.005.
Myxoid liposarcoma is classified in the group of sarcomas with adipose differentiation, which is the second most common group of sarcomas. However, myxoid liposarcoma is not a homogeneous entity, because the behavior and clinical course of these tumors can vary widely. This study aimed to describe the magnetic resonance imaging (MRI) features of myxoid liposarcomas and to determine whether the MRI features are associated with the histologic grade and can differentiate between low-grade and high-grade tumors and thus help in clinical decision making.
We studied 36 patients with myxoid liposarcomas treated at our center between 2010 and 2018. We analyzed clinical variables (age, sex, and tumor site) and MRI features (size, depth, borders, fatty component, myxoid component, non-fatty / non-myxoid component, apparent diffusion coefficient (ADC), and type of enhancement after the administration of intravenous contrast material). We correlated the MRI features with the histologic grade and the percentage of round cells.
In our series, patients with myxoid liposarcomas were mainly young adults (median age, 43 years). There were no differences between sexes; 97.2% were located in the lower limbs, 86.1% were deep, and 77.8% had well-defined borders. Of the 23 myxoid liposarcomas that contained no fat, 16 (69.6%) were high grade (p=0.01). All the tumors with a myxoid component of less than 25% were high grade (p=0.01); 83.3% of those with a non-fatty / non-myxoid component greater than 50% were high grade (p=0.03) and 61.5% had more than 5% round cells (p=0.01). Diffusion sequences were obtained in 14 of the 36 patients; ADC values were high (median, 2 x 10 mm/s), although there were no significant associations between low-grade and high-grade tumors. Contrast-enhanced images were available for 30 (83.3%) patients; 83.3% of the tumors with heterogeneous enhancement were high grade (p=0.01).
MRI can be useful for differentiating between high- and low-grade myxoid liposarcomas and can help in clinical decision making.
黏液样脂肪肉瘤归类于具有脂肪分化的肉瘤组，是第二常见的肉瘤组。然而，黏液样脂肪肉瘤并非单一实体，因为这些肿瘤的行为和临床病程差异很大。本研究旨在描述黏液样脂肪肉瘤的磁共振成像（MRI）特征，并确定MRI特征是否与组织学分级相关，能否区分低级别和高级别肿瘤，从而有助于临床决策。
我们研究了2010年至2018年在本中心接受治疗的36例黏液样脂肪肉瘤患者。我们分析了临床变量（年龄、性别和肿瘤部位）以及MRI特征（大小、深度、边界、脂肪成分、黏液样成分、非脂肪/非黏液样成分、表观扩散系数（ADC）以及静脉注射对比剂后的强化类型）。我们将MRI特征与组织学分级和圆形细胞百分比进行了关联分析。
在我们的系列研究中，黏液样脂肪肉瘤患者主要为年轻成年人（中位年龄43岁）。性别之间无差异；97.2%位于下肢，86.1%为深部肿瘤，77.8%边界清晰。在23例不含脂肪的黏液样脂肪肉瘤中，16例（69.6%）为高级别（p=0.01）。所有黏液样成分少于25%的肿瘤均为高级别（p=0.01）；非脂肪/非黏液样成分大于50%的肿瘤中83.3%为高级别（p=0.03），61.5%有超过5%的圆形细胞（p=0.01）。36例患者中有14例进行了扩散序列检查；ADC值较高（中位值为2×10⁻³mm²/s），尽管低级别和高级别肿瘤之间无显著关联。30例（83.3%）患者有增强图像；83.3%强化不均匀的肿瘤为高级别（p=0.01）。
MRI有助于区分高级别和低级别黏液样脂肪肉瘤，并有助于临床决策。
