颅内间变型血管外皮细胞瘤与间变型脑膜瘤的影像与病理对照

目的：对比分析颅内间变型血管外皮细胞瘤与间变型脑膜瘤的影像学差异。方法：回顾性分析经手术病理证实的间变型血管外皮细胞瘤19例，间变型脑膜瘤20例，所有病例均行MR平扫及增强扫描，并与病理表现进行对照分析。结果：所有39例病例均位于颅内脑外。19例间变型血管外皮细胞瘤中病灶呈分叶状或不规则形16例，跨叶生长9例。MR平扫T1WI呈等、稍低混杂信号15例，等信号4例，T2WI呈高、低混杂信号13例，高信号6例，增强扫描呈不均匀显著强化13例，明显囊变坏死12例，“硬膜尾征”4例，颅骨破坏9例。术后肿瘤组织学显示瘤细胞密集，细胞异型性明显，核分裂相多见，网状纤维染色见间质有大量裂隙状血管。20例间变型脑膜瘤患者中病灶呈分叶状或不规则形16例，跨叶生长2例。MR平扫T1WI呈等、低信号12例，呈等、高信号3例，较均匀信号5例；T2WI呈等、略高混杂信号17例，呈高、低混杂信号3例；中等度不均匀强化15例，明显坏死囊变13例，“硬膜尾征”14例，颅骨破坏11例。病理示瘤细胞分化不良，有丝分裂丰富，细胞密集，核增大，深染，异型性明显，核分裂相多见。结论：颅内间变型血管外皮细胞瘤与间变型脑膜瘤影像表现存在差异，前者具有更明显的跨叶生长倾向，T2WI呈明显高信号，肿瘤增强程度显著，多窄基底与硬膜相连，少见“硬膜尾征”等特点，可与后者鉴别。

Comparison of imaging and pathological findings of intracranial anaplastic hemangiopericytoma and anaplastic meningioma

Objective： To compare and analyze imaging features of intracranial anaplastic hemangiopericytoma （HPC） and anaplastic meningioma. Methods： Nineteen patients of anaplastic HPC and twenty patients of anaplastic meningioma proved by operation and pathology were analyzed retrospectively. Both plain and enhanced MR scans were performed and the results were compared with pathology in all cases. Results： All the intracranial tumors were located outside the brain. Sixteen cases were lobulated, 9 cases extended into adjacent lobe in 19 anaplastic HPC. On MRI, the lesions showed mixed iso-low signal （n=15） or iso-signal（n=5） on plain T1WI, while mixed high-low signal（n=13） or high signal（n=6） on plain T2WI. After contrast injection, heterogeneous enhancement was seen in 13 cases. Significant necrotic and cystic areas were seen in 12 cases, ＂du- ral tail sign＂ in 4 cases. Seven cases appeared to have bony destruction. Significant mass effect in all cases. Sixteen cases showed significant peritumoral edema. Postoperative tumor histology revealed that the tumor cells were densely aggregated, ap- parent cellular atypia, mitosis common. Reticular fiber staining showed a large number of slit-like vascular spaces within the interstitial tissue. Sixteen cases of the 20 anaplastic meningiomas were lobulated or irregular in shape. On MRI, the lesions showed mixed iso-low signal（n=12） or iso-high signal（n=3）; iso-signal（n=5） on plain T1WI, mixed slight iso-high signal（n=17） or mixed high-low signal（n=3） on plain T2WI, moderate heterogeneous enhancement in 16 cases, obvious cystic necrosis in 13 cases, ＂dural tail sign＂ in 14 cases, the skull destruction in 9 cases, peritumoral edema in 16 cases. The pathology showed a poorly differentiated tumor cells, mitosis rich, cell densely aggregated, nucleus enlarged, deep dyeing, significant atypia, mitotic common. Conclusion： Imaging findings of intracranial anaplastic HPC and anaplastic meningioma are different, the former has a more cross-lobe growth tendency, significantly higher signal on plain T2WI, significant enhancement, subdural connected with a narrow base, ＂dural tail sign＂ rare, etc, with these characteristics can be identified with the latter.