肌肉原发非霍奇金淋巴瘤的MRI表现

目的 分析肌肉原发非霍奇金淋巴瘤的MRI表现,探讨MR诊断价值.方法 回顾性分析6例经手术病理证实的肌肉原发非霍奇金淋巴瘤6例,初诊时均无明确淋巴瘤病史,术前分别经MRT1WI、T2WI和T2WI增强检查.仔细复习MR扫描结果并和手术病理作回顾性对照分析.结果 6例肌肉原发非霍奇金淋巴瘤中,位于颈部2例、上肢1例、下肢3例.6个病灶皆起源于深部肌肉并累及多个肌群,5例病灶侵犯到皮下脂肪间隙,1例累及皮肤,3例肿瘤沿着神经血管束浸润.病灶呈不规则形5例,卵圆形1例.病灶直径7.3～22.5 cm,平均13.9 cm.境界不清楚5例,清楚1例.MR T1WI略高信号2例,略低信号4例,信号均匀;T2WI呈略高信号2例,中等程度高信号3例,高信号1例,信号略不均匀5例,均匀1例.5例瘤内可见固有解剖结构(增粗的肌纤维、肌腱和肌间脂肪)残留.MR动态增强扫描5例,动脉期呈中等程度强化,强化较均匀2例,略不均匀3例;实质期持续强化,强化较均匀3例,略不均匀2例.结论 原发肌肉淋巴瘤在T1WI多呈等低均匀信号,T2WI信号强度低于绝大多数软组织恶性肿瘤,也有一定的参考价值.

MRI manifestations of primary muscle non-Hodgkin lymphoma

Objective To explore and evaluate MRI in diagnosing primary muscle non-Hodgkin lymphoma. Methods Six surgically confirmed primary muscle non-Hod#in lymphoma underwent MR examination including T1WI, T2WI and T1 WI enhanced studies. The acquired images date was reviewed and analysed retrospectively in comparison with surgical and pathological results. Results The locations of 6 cases were cervical part (2), upper extremity (1), lower extremity (3), respectively. All cases involved of more than one anatomical compartment with poorly defined solid masses in 5 cases and well defined in 1 cases, 5 extended to subcutaneous fat and 3 extended along the neurovascular bundle. The mean tumor diameter was 13.9 cm, ranging from 7.3 to 22.5 cm. One was well demarcated and 5 were ill-defined. On T1 WI, 2 were slighdy high signal intensity and 4 were slighdy low signal intensity. On T2 WI, 2 were slightly high signal intensity, 3 were intermediate signal intensity and 1 was high signal intensity. Five were inhomogeneous and 1 was homogeneous. The intrinsic structure such as muscle fiber, tendo, spatium intermusculare were detected on 5 cases. Of the 5 dynamic contrast-enhanced cases, it showed moderate enhamcement during arterial phase, 2 were homogeneous and 3 were inhomogeneous. And it showed progressive enhancement during interstitial phase, 3 were homogeneous and 2 were inhomogeneous. Conclusions Primary muscle lymphoma always originated deep to the fascia showing subcutaneous extension and multiple compartment invasion. Typically form poorly defined solid masses with slightly high in signal intensity on MR T2WI and middle degree dynamic delayed contrasted-enhanced in which intrinsic anatomic structure such as muscle fiber, tendo, spatium intermusculare and so on can be discerned, almost all cases involve more than one muscle compartment and some of tumor extend along the neurovascular bundle.