Department of Radiology, Daping Hospital, Army Medical University, Chongqing, 400042, China.
Chongqing Clinical Research Centre of Imaging and Nuclear Medicine, Chongqing, 400042, China.
BMC Med Imaging. 2020 Aug 26;20(1):100. doi: 10.1186/s12880-020-00498-9.
The aim of this study was to characterize the radiological features of myofibroma on multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) and correlate the imaging findings with pathologic features.
The radiological findings of 24 patients with 29 myofibromas were retrospectively reviewed. All images were evaluated with emphasis on density, signal intensity, hypointense area, and enhancement, correlating these with pathologic findings.
On plain MDCT scan, 4(26.7%) tumors were homogeneous isodensity, 4(26.7%) tumors were heterogeneous hyperdensity, and 7(46.7%) tumors were heterogeneous hypodensity. On contrast-enhanced MDCT scan, all tumors (9/9) showed heterogeneous enhancement with moderate in 3(33.3%) and marked in 6(66.7%) tumors, and their enhancements were higher compared to adjacent skeletal muscle (P = 0.0001). On MRI, heterogeneous slight hyperintensity, homogeneous slight hyperintensity, and heterogeneous hypointensity on T1-weighted imaging (T1WI) were observed in 14(82.3%), 1(5.9%) and 2(11.8%) tumors, respectively. On T2-weighted imaging (T2WI) and fat-suppressed (FS) T2WI, all tumors demonstrated heterogeneous hyperintensity. All tumors showed heterogeneous marked enhancement on FS contrast-enhanced T1WI. On T1WI, T2WI, FS T2WI, and FS contrast-enhanced T1WI, irregular strip or/and patchy hypointensities were found in 16(94.1%), 12(100%), 17(100%) and 17(100%) tumors, respectively, and pseudocapsule was seen in 5(29.4%) tumors. The hypointensities and pseudocapsule on MRI were exactly corresponding to pathological interlacing collagen fibers and fibrosis. The age of the recurrent group was lower than that of the non-recurrent group (P = 0.001) and the tumors without pseudocapsule were more likely to recur than those with pseudocapsule (P = 0.034).
Myofibromas are characterized by heterogeneous density or signal intensity, with moderate or marked enhancement. The hypointensities and pseudocapsule on MRI may be helpful in diagnosis, and the absence of pseudocapsule and younger age may be risk factors for tumor recurrence.
本研究旨在描述多排 CT（MDCT）和磁共振成像（MRI）上肌纤维瘤的影像学特征，并将影像学表现与病理特征相关联。
回顾性分析 24 例 29 个肌纤维瘤患者的影像学资料。重点评估密度、信号强度、低信号区和增强程度，并将这些与病理结果相关联。
平扫 MDCT 上，4 个（26.7%）肿瘤为均匀等密度，4 个（26.7%）肿瘤为混杂高密度，7 个（46.7%）肿瘤为混杂低密度。增强 MDCT 扫描时，所有肿瘤（9/9）呈不均匀强化，3 个（33.3%）为中度强化，6 个（66.7%）为明显强化，与相邻骨骼肌相比，增强程度更高（P=0.0001）。MRI 上，14 个（82.3%）肿瘤 T1WI 呈不均匀稍高信号，1 个（5.9%）肿瘤呈均匀稍高信号，2 个（11.8%）肿瘤呈不均匀低信号；T2WI 和脂肪抑制 T2WI（FS T2WI）上所有肿瘤均呈不均匀高信号。FS 对比增强 T1WI 上，所有肿瘤均呈不均匀明显强化。T1WI、T2WI、FS T2WI 和 FS 对比增强 T1WI 上，16 个（94.1%）肿瘤显示不规则条状或/和斑片状低信号，12 个（100%）肿瘤显示假包膜，17 个（100%）肿瘤显示 T2WI 和 FS T2WI 不均匀高信号，17 个（100%）肿瘤显示 FS 对比增强 T1WI 不均匀明显强化。MRI 上的低信号和假包膜与病理上的交织胶原纤维和纤维化完全对应。复发性肿瘤组的年龄低于非复发性肿瘤组（P=0.001），无假包膜的肿瘤比有假包膜的肿瘤更容易复发（P=0.034）。
肌纤维瘤的特征是密度或信号强度不均匀，增强程度为中度或明显。MRI 上的低信号和假包膜有助于诊断，无假包膜和年龄较小可能是肿瘤复发的危险因素。
