MRI对下肢软组织肿瘤及肿瘤样病变的诊断价值

Value of MRI in diagnosis of soft tissue tumors and tumor-like lesions in lower limb

目的:探讨MRI对下肢软组织肿瘤及肿瘤样病变的诊断价值。方法:回顾性分析25例经病理证实的下肢软组织肿瘤及肿瘤样病变的MRI表现。结果:25例中,良性11例,其中脂肪瘤5例,骨化性肌炎1例,假性动脉瘤1例,血管瘤4例;恶性14例,其中滑膜肉瘤6例,转移瘤3例,恶性纤维组织细胞瘤1例,平滑肌肉瘤1例,纤维肉瘤1例,脂肪肉瘤2例。良性组肿块最大径平均(8.36±3.50)cm,恶性组(11.9±4.61)cm,2组差异有统计学意义(P<0.05)。良性组病变内部信号T1WI、T2WI以均匀中等或中等偏高信号为主,1例伴瘤周水肿;恶性组病变内部信号T1WI、T2WI以不均匀低信号为主的混杂信号,4例伴瘤周水肿(P>0.05)。良性组6例未强化,恶性组均不同程度强化;良性组5例STIR呈低信号,恶性组2例STIR呈低信号;良性组无周围组织侵犯,恶性组8例伴周围组织侵犯,以上征象2组差异均有统计学意义(均P<0.05)。结论:MRI能清晰显示软组织肿瘤及肿瘤样病变的边界、范围、大小、内部成分及与周围组织的关系,对良恶性的鉴别诊断价值较高。

Objective:To investigate the value of MRI in the diagnosis of soft tissue tumors and tumor-like lesions in lower limb.Methods:25 cases with pathology proven soft tissue tumors and tumor-like lesions in lower limb were retrospectively reviewed and analyzed of its MRI characteristics.Results:There were 14 malignant tumors including synovial sarcoma(6 cases),metastatic tumors(3 cases),malignant fibrous histiocytoma(1 case),leiomyosarcoma(1 case),fibrosarcoma(1 case)and liposarcoma(2 cases).There were 11 benign tumors including lipoma(5 cases),myositis ossificans(1 case),pseudoaneurysm(1 case)and hemangioma(4 cases).The maximum diameter of the tumor was(8.36±3.50)cm for benign group and(11.9±4.61)cm for malignant group with significant statistical difference(P<0.05).On non-enhanced MRI,the signal intensities in benign tumors mostly manifested as homogeneous iso-intensity or homogeneous iso-hyperintensity on both TIWI and T2WI,and one case with peritumoral edema.The signal intensities in malignant tumors mostly manifested as in-homogeneous low-intensity on both T1WI and T2WI,and four cases with peritumoral edema(P>0.05).In benign tumors,there were 6 cases with non-enhancement,5 cases with low-intensity in STIR sequence and no surrounding tissue invasion;however,in malignant tumors,all cases with different levels of enhancement,2 cases with low-intensity in STIR sequence and 8 cases with surrounding tissue invasion(P<0.05).Conclusion:MRI could clearly display the margin,the size,internal composition and the relationship with the surrounding.It is usefully to determine the benign and malignant.