BACKGROUND Myxoid tumors pose diagnostic challenges for radiologists and pathologists. All myxoid tumors can be differentiated from each other using fluorescent in-situ hybridization (FISH) or immunohistochemical markers, except for myxomas and myxofibrosarcomas. Myxomas and myxofibrosarcomas are rare tumors. Myxomas are benign and histologically bland, whereas myxofibrosarcomas are malignant and histologically heterogenous. Because of the histological heterogeneity, low grade myxofibrosarcomas may be mistaken for myxomas on core needle biopsies. We evaluated the performance of T1-weighted signal intensity (T1SI), tumor volume, and radiomic features extracted from magnetic resonance imaging (MRI) to differentiate myxomas from myxofibrosarcomas. METHODS The MRIs of 56 patients (29 with myxomas, 27 with myxofibrosarcomas) were analyzed. We extracted 89 radiomic features. Random forests based classifiers using the T1SI, volume features, and radiomic features were used to differentiate myxomas from myxofibrosarcomas. The classifiers were validated using a leave-one-out cross-validation. The performances of the classifiers were then compared. RESULTS Myxomas had lower normalized T1SI than myxofibrosaromas (p = 0.006) and the AUC using the T1SI was 0.713. However, the classification model using radiomic features had an AUC of 0.885 (accuracy = 0.839, sensitivity = 0.852, specificity = 0.828), and outperformed the classification models using T1SI (AUC = 0.713) and tumor volume (AUC = 0.838). The classification model using radiomic features was significantly better than the classifier using T1SI values (p = 0.039). CONCLUSIONS Myxofibrosarcomas are on average higher in T1-weighted signal intensity than myxomas. Myxofibrosarcomas are larger and have shape differences compared to myxomas. Radiomic features performed best for differentiating myxomas from myxofibrosarcomas compared to T1-weighted signal intensity and tumor volume features.

中文翻译：

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MRI 的放射组学特征可区分粘液瘤和粘液纤维肉瘤。

背景技术粘液样肿瘤给放射科医生和病理学家带来了诊断挑战。除粘液瘤和粘液纤维肉瘤外，所有粘液样肿瘤均可使用荧光原位杂交 (FISH) 或免疫组织化学标记物进行区分。粘液瘤和粘液纤维肉瘤是罕见的肿瘤。粘液瘤是良性的，组织学上是平淡的，而粘液纤维肉瘤是恶性的，组织学上是异质的。由于组织学异质性，低级别粘液纤维肉瘤可能会在芯针活检中被误认为是粘液瘤。我们评估了 T1 加权信号强度 (T1SI)、肿瘤体积和从磁共振成像 (MRI) 中提取的放射组学特征的性能，以区分粘液瘤和粘液纤维肉瘤。方法 对 56 例患者（29 例粘液瘤，27 例粘液纤维肉瘤）的 MRI 进行分析。我们提取了 89 个放射组学特征。使用 T1SI、体积特征和放射组学特征的基于随机森林的分类器用于区分粘液瘤和粘液纤维肉瘤。使用留一交叉验证对分类器进行验证。然后比较分类器的性能。结果 粘液瘤的标准化 T1SI 低于粘液纤维肉瘤 (p = 0.006)，使用 T1SI 的 AUC 为 0.713。然而，使用放射组学特征的分类模型的 AUC 为 0.885（准确度 = 0.839，敏感性 = 0.852，特异性 = 0.828），并且优于使用 T1SI（AUC = 0.713）和肿瘤体积（AUC = 0.838）的分类模型。使用放射组学特征的分类模型明显优于使用 T1SI 值的分类器 (p = 0.039)。结论 粘液纤维肉瘤的 T1 加权信号强度平均高于粘液瘤。与粘液瘤相比，粘液纤维肉瘤更大且形状不同。与 T1 加权信号强度和肿瘤体积特征相比，放射组学特征最适合区分粘液瘤和粘液纤维肉瘤。