四肢软组织肿物的MRI囊变征象及其临床意义

MRI cystic changes of soft tissue masses in extremities and its clinical significance

目的分析四肢软组织肿物的MRI囊变征象及其临床意义。方法回顾性分析30例四肢软组织囊性肿块患者的病理结果及MRI资料。比较良恶性病变的MRI囊变征象;采用logistic回归模型分析与四肢软组织肿物良恶性相关的囊变征象;采用受试者工作特性曲线(ROC)分析相关征象鉴别四肢良恶性软组织肿物的价值。结果 30例四肢软组织囊性肿块包括良性17例,恶性13例。良恶性病灶囊变灶数目、囊变区分布、有无壁结节及壁结节大小比较,差异均无统计学意义(P>0.05);与恶性病灶比较,良性病变囊液及囊壁信号大多均匀,且囊壁较薄(均P<0.05)。多因素logistic回归分析示,囊壁厚度增大是四肢软组织肿物为恶性的危险因素(P<0.05);ROC曲线结果显示,囊壁厚度征象鉴别良恶性四肢软组织肿物的最佳阈值为4.28 mm,灵敏度、特异度分别为84.6%、88.2%,曲线下面积为0.887。结论良恶性四肢软组织肿物的MRI囊变征象各有特点,其中囊壁厚度征象对鉴别软组织肿物良恶性有重要的作用。

Objective To analyze the MRI cystic changes of soft tissue masses in extremities and its clinical significance.Methods The pathological results and MRI data of 30 patients with cystic degeneration of soft tissue masses in extremities were retrospectively analyzed. The MRI cystic changes were compared between benign lesions and malignant lesions. Logistic regression model was used to analyze the cystic changes associated with quality of soft tissue masses in extremities. The receiver operating characteristic（ ROC） curve was used to analyze the value of related cystic changes for differential diagnosis of the quality of soft tissue masses in extremities. Results Thirty soft tissue masses with cystic degeneration in extremities consisted of 17 benign masses and 13 malignant masses. There were no significant differences in the number or distribution of cystic lesions,the presence or the size of intracystic wall nodules between malignant and benign masses（ P〈0. 05）.The signals of cystic fluid and wall were homogeneous,and the cystic wall was thicker in benign lesions compared to the malignant lesions（ all P〈0. 05）. Multivariate logistic regression analysis revealed that the increased thickness of cystic wall was the risk factor for malignant soft tissue masses in extremities（ P〈0. 05）. The result of ROC curve showed that the optimal cut-off of cystic wall thickness was 4. 28 mm for differential diagnosis of the quality of soft tissue masses in extremities,the sensitivity,specificity and the area under curve were 84. 6%,88. 2%and 0. 887 respectively. Conclusion There is a difference in the MRI cystic features between benign and malignant soft tissue masses in extremities. The thickness of cystic wall is important for differential diagnosis of the quality of soft tissue masses in extremities.