睾丸精原细胞瘤的低场MR诊断

MRI Diagnosis of Seminoma in Testis

目的探讨睾丸精原细胞瘤的MRI表现,以提高对该病的影像学认识。资料与方法搜集12例经手术病理证实的睾丸精原细胞瘤,左侧5例,右侧7例;发病年龄17～54岁,平均36.8岁;着重分析肿瘤的好发年龄、部位、MRI信号特点、肿瘤强化情况。结果睾丸精原细胞瘤MRI表现具有以下特点:(1)肿瘤多呈类圆形或分叶状实性肿块,边界清晰,无完整包膜,个别肿瘤较大可替代整个睾丸,内部伴有囊变、出血。(2)肿瘤实质T1WI呈等或稍低信号,与正常睾丸组织不能区分,T2WI呈均匀一致低信号,与正常睾丸组织显著高信号对比鲜明。(3)增强扫描肿瘤无强化或轻度强化,纤维血管分隔明显强化。(4)白膜对肿瘤邻近扩散有阻隔作用。结论睾丸精原细胞瘤MRI表现具有一定特征性,结合其临床表现,术前MRI检查有助于定性诊断。

Objective To evaluate the MRI appearances of seminoma in testis and to improve the recognization of the diseases imaging. Materials and Methods MR findings of 12 cases with surgically and histopathologically proved testicular seminoma were analyzed. 5 cases were located in the left testes, and 7 in the right testes. Results The typical MR manifestations of testicular seminoma were as follows. （ 1 ） The tumors were similar to round or abnormity solid masses ,with clear borderline and without full encapsulation, a few larger tumors were as large as the whole testis with cystoid degeneration and haemorrhage in the intratesticular lesions; （2） The masses were demonstrated as isointensity signal or slightly hypointensity on T1 weighted image, and the masses were not differentiated from the normal testes. Homogeneous hypointensity on T2 weighted image were showed compared with the remarkable hyperintensity in the normal testes; （3） The presence of non enhancement or slightly enhancement,with fibrovascutar septa enhancing significantly after contrast material administration were observed; （4） Tunica albuginea could hold up the spread of tumors without involvement. Conclusion There are typical MRI features of testicular seminomas, MRI plays an important role in the qualitative presurgery diagnosis combined with the clinical appearances.