骨盆尤文氏肉瘤/外周型原始神经外胚层肿瘤影像征象与临床病理对照分析

Imaging Features of Ewing's Sarcoma/Peripheral Primitive Neuroectodermal Tumor in Pelvic Bones:Correlations with Clinic and Pathological Findings

目的探讨骨盆尤文氏肉瘤/外周型原始神经外胚层肿瘤(ES/p PNET)的影像学表现,并与临床及病理对照,进一步加深对该病的认识。方法回顾性分析经病理证实的8例骨盆原发性ES/p PNET临床、病理及影像学资料。所有病例均行常规X检查,其中4例同时行CT检查,7例行MR检查。影像学观察指标包括:发病部位、数目、骨质破坏、骨膜反应及瘤骨、软组织肿块、强化方式等。病理学观察指标包括形态学和免疫组织化学。结果 7例表现为溶骨性骨质破坏;1例表现以骨硬化为主要改变;7例见与骨质破坏不呈比例的巨大的软组织肿物,中央区多发坏死囊变;最大径大于8cm的肿瘤6例;4例跨关节浸润。MRI显示软组织肿物内可见T2WI低信号分隔影,增强扫描部分强化。6例出现转移,其中3例为肺转移。免疫组化8例患者CD99均为阳性表达。结论原发于骨盆的ES/PNET具有一定特点,但缺乏特异性,确诊仍需组织病理学检查。对于青少年患者,结合影像学上溶骨性骨质破坏并明显软组织肿块,需考虑骨盆ES/PNET可能。

Objective Objective To discuss the imaging findings of ES/p PENT in pelvic bones and to improve the cognition. Methods Methods Eight patients with ES/p PENT in pelvic bones with pathologically proved were retrospectively analyzed for their clinical, pathologic and radiologic features. All the patients were underwent X-ray examination, 4 patients performed CT examination, and 7 patients performed MR. Imaging findings include： the location, number, bone destruction, periosteum reaction and bone, soft tissue mass, and enhancement mode. Pathological examination of the observed indicators include morphology and immunohistochemistry. Results 7 cases showed osteolytic bone destruction; and only one case showed sclerosis bone destruction.7 cases showed huge and uneven density soft tissue mass with bone destruction, and in 6 cases which the maximum diameter of the tumor were more than 8cm.4 cases involved the adjacent joints; MR imaging showed line dark signal interval in soft tissue mass on T2WI, with partly enhancement. 6 cases was found with metastases, and 3 were in pulmonary. Immunohistochemical CD99 of all cases were positive expression. Conclusion ES/p PENT shows certain characteristics, but lacks the specificity. Pathological examination is mandatory to confirm the diagnosis. For young patients with bone destruction and soft tissue mass, the chance of ES/p PNET should be considered.