腹盆部孤立性纤维瘤的MRI表现及相关病理分析

MRI Manifestations and Related Pathological Analysis of Solitary Fibroma in the Abdomen and Pelvis

目的:探讨腹盆部孤立性纤维瘤(SFT)的MRI表现与病理特征,以提高术前对SFT非常见部位的影像学诊断。方法:回顾性研究深圳市第二人民医院2018年1月1日至2018年12月31日收治的13例经手术及病理证实的腹盆部SFT的患者的MRI表现及病理特点。结果:13例患者中,7例位于腹部,6例位于盆部;均为良性病变;9例表现为实性包块,4例表现为囊实性包块;8例表现为类圆形,5例表现为不同程度的分叶状;最大直径为6.9 cm;肿瘤边界清楚,不同程度地压迫、推挤邻近的器官结构;11例于T2WI呈不均匀高低混杂信号;2例表现为均匀稍低或等信号;增强扫描动脉期呈快速明显的强化,延迟期仍较呈明显的强化,呈“快进-慢出”的强化方式,短T2区域强化更加明显。在病理学方面,镜下病灶主要表现为呈束状、编织状分布的梭形细胞,呈血管外皮细胞瘤样生长,间质可见丰富红染的胶原纤维;免疫组化可见CD34、Vimentin均表现为强阳性。结论:腹盆部边界清楚的孤立性包块,T2WI呈混杂信号,短T2区域明显强化,“快进-慢出”的强化方式,需考虑SFT的可能。

Objective To investigate the MRI findings and pathological features of solitary fibrous tumor(SFT)in the abdominal and pelvic region,to improve the imaging diagnosis of SFT before surgery in rare region.Methods The MRI findings and clinical pathological characteristics of 13 patients with abdominal or pelvic SFT confirmed by surgery and pathology were retrospectively studied.Results In those 13 tumors,7 were located in the abdominal cavity,6 were located in the pelvis cavity;all of them were confirmed to be benign;9 showed solid masses and 4 showed cystic-solid masses;the largest maximum diameter was 6.9 cm.8 cases were in round shape,and 5 cases were in lobular shape;All of them were displaying clear boundary,compressing and pushing adjacent organ structures;On T2WI,11 cases showed mixed hyperintense and hypointense signals,and 2 case showed homogeneously mild hypo-intensity or iso-intensity signals;After contrast enhanced,the solid part of tumors enhanced markedly in the arterial phase,and showed progressive enhancement in the venous and delayed phase,with the enhancement model of"rapid wash in and slow wash out",and the enhancement in the short T2 area was more obvious.On pathological study,tumor cells were spindle-shaped,bundle and braided distribution,growing like hemangiopericytomas,and rich in collagen fibers,microscopically;Cells were strongly immunopositive for CD34,Vimentin.Conclusion The isolated abdominal or pelvic mass with clear borders,mixed signals in T2WI,obviously enhanced in short T2 region,and"rapid wash in and slow wash out"enhancement model,which should consider the possibility of SFT.