隆突性皮肤纤维肉瘤的影像表现及临床病理特征

Imaging and clinicopathologic features of dermatofibrosarcoma protuberans

目的:探讨隆突性皮肤纤维肉瘤(DFSP)的影像表现及临床病理特征,提高该病的诊断及鉴别水平。方法:回顾性分析经病理证实的35例DFSP患者的临床及影像资料。结果:35例患者中单发31例,多发4例,共40个病灶;34例位于皮肤或皮下脂肪层,1例位于浅筋膜下层;发生于躯干21例,四肢10例,头面部4例。病灶多呈不规则形或梭形,其中14个病灶伴有“子结节外突征”,23个病灶伴有“多结节征”,5个病灶伴有“悬吊征”。病灶最大径1.3~18.6 cm,平均5.1 cm。病变CT平扫呈等或稍低密度,增强扫描多呈轻中度不均匀强化。T1WI多呈等、稍低信号,T2WI-FS多呈均匀或混杂高信号,部分病灶内可见“双低信号征”,DWI呈高信号,增强扫描呈均匀或不均匀明显强化。病灶多合并周围侵袭征象,26例见“皮肤尾征”,32例见“脂肪尾征”,16例见“筋膜尾征”。病理表现为真皮及皮下组织的梭形肿瘤细胞围绕血管呈“车辐状”排列。免疫组化CD34、Vimentin多呈阳性,CK、S-100蛋白多呈阴性。结论:DFSP的发病部位、CT及MRI表现具有一定特征性,术前检查有助于其准确定性及临床手术方案制定。

Objective:To analyze the CT/MRI findings and pathological features of dermatofibrosarcoma protuberans(DFSP)to improve this diagnosis and differentiation level of this disease.Methods:The clinical data,pathological types,and CT/MRI findings of 35 cases with DFSP confirmed by pathology were analyzed retrospectively.Results:Among the 35 patients,31 cases were single,and four were multiple,with 40 lesions.Thirty-four cases were located in the skin or subcutaneous tissue,one under the superficial fascia,21 cases occurred in the trunk,10 in the limbs,and 4 in the head and face.Most of the lesions were irregular or spindle-shaped,of which 14 lesions were accompanied by a"nodular protruding sign,"23 lesions were accompanied by a"multiple nodules sign,"and five lesions were accompanied by a"overhanging sign."The maximum diameter of the lesions was 1.3~18.6cm,with an average of 5.1cm.The plain CT scan showed homogeneous isodensity or slightly lower density than the surrounding soft tissue,and most showed mild to moderate heterogenous enhancement.Most of the cases showed iso-intensity or slightly hypo-intensity on T 1WI,hyperintensity or heterogenous hyperintensity on T 2WI-FS,in which"double low signal sign"was seen in some lesions,hyperintensity on DWI,and enhanced scanning showed remarkable homogeneous or heterogenous enhancement.Most of the lesions were complicated with peripheral invasion signs,including"skin tail sign"in 26 cases,"fat tail sign"in 32 cases and"fascia tail sign"in 16 cases.Microscopically,DFSP is characterized by spindle-shaped tumour cells arranged in a"cartwheel"pattern around blood vessels and infiltrated in the dermis and subcutaneous tissue.Immunohistochemistry for CD34 and vimentin were mostly positive,with CK and S100 negative.Conclusion:The location,CT and MRI findings of DFSP have certain specific characteristics,and preoperative examination helps to determine its diagnostic accuracy and formulate clinical surgical plans.