慢性淋巴水肿相关恶性软组织肿瘤MRI表现

目的 分析与慢性淋巴水肿相关的软组织恶性肿瘤的MRI表现。方法 回顾性分析8例慢性淋巴水肿相关的软组织恶性肿瘤的临床资料及MRI表现。结果 病变发生于上臂5例，前臂1例，小腿1例，足部1例。5例血管肉瘤T1WI呈中等信号，T2WI表现为低信号，增强后显著强化。2例原发性皮肤弥漫大B细胞淋巴瘤表现为明显突出于皮肤表面的分叶状等T1稍长T2信号软组织肿块，其内短T2分隔明显强化。1例黏液炎性纤维母细胞肉瘤边缘光滑，T1WI呈稍低信号，T2WI呈高信号。结论 慢性淋巴水肿所致局部免疫缺陷可引发多种软组织恶性肿瘤，MRI上其共同特点为皮肤及皮下软组织结节，其中血管肉瘤病灶多发且显著强化有助于与其他肿瘤的鉴别。

MRI appearances of malignant soft tissue tumors associated with chronic lymphedema

Objective To observe MRI features of malignant soft tissue tumors associated with chronic lymphedema. Methods MR imaging and clinic data of 8 patients with malignant soft tissue tumors associated with chronic lymphedema were retrospectively analyzed. Results The tumors occurred in upper arm (n=5), forearm (n=1), leg (n=1) or foot (n=1). Angiosarcoma (n=5) manifested as intermediate signal on T1WI and hypointensity signal on T2WI, with intense and uniform enhancement after administration of contrast media. Primary cutaneous diffuse large B-cell lymphoma (n=2) showed soft tissue masses protruded from the skin with intermediate signal on T1WI, slight hyperintensity signal on T2WI, and the low signal intensity septum enhanced obviously after administration of contrast media. Myxoinflammatory fibroblastic sarcoma (n=1) showed slight hypointensity signal on T1WI and hyperintensity signal on T2WI with smooth margins. Conclusion Chronic lymphedema impairs local immune surveillance, which can cause various malignant soft tissue tumors, The common character of them on MRI is skin and subcutaneous soft tissue nodules. Multiple foci and obvious enhancement is a special pattern of STS, which is help to differential diagnosis with the other tumors.