骨原始神经外胚层肿瘤（2例报告并文献复习）

目的；提高对骨原始神经外胚层肿瘤的认识。材料与方法：对２例骨原始神经外胚层肿瘤的临床表现、影像特征进行描述，并结合文献分析。结果：（１）骨原始神经外胚层肿瘤来源于神经嵴的胚胎迁移细胞。（２）多见于儿童和青少年，发病部位以胸部最常见，其余部位还有骨盆，四肢等。（３）影像表现一般呈溶骨性骨折破坏伴有软组织肿块，多有囊变，少见瘤骨和钙化。（４）Ｅｗｉｎｇ‘ｓ瘤与骨原始神经外胚层肿瘤在组织学起源上是相关性

Osseous Primitive Neurectodermal Tumor: A Report of 2 Cases and a Review of Literature

Objective: To make a further understanding of osseous primitive neuroectodermal tumor (PNET). Materials and Methods: The clinical findings and the imaging features of 2 cases with osseous PNEI were described and analyzed. Results: (1) Osseous PNET originated from embryonic migrating cells of neural crest. (2) Osseous PNET occurred more often in children and adolescence. Thorax, Pelvis, and limbs were the sites of predilection. (3) Osseous PNET usually presented as osteolytic destricion with soft tissue mass, and most cases showed cystic degeneration. Naoplastic bone formation and calcificatiou were seldom seen. (4) Ewing's sarcoma and osseous PNEI were histogenetically related and represented diffren stages of cell differentiation. Conclusion: The diagnosis of osseous PNEI is difficult to make solely by imaging features. Confirmatory diagnosis is based on pathologic examination, but a full understandung of PNEI is essential.