周围神经上皮瘤（Peripheralneroepithelioma）和尤文肉瘤（Ewing’sSarcoma。）都是小圆形细胞恶性肿瘤，组织学形态十分相似。前者起源于周围神经，后者来源不明。但目前有越来越多的证据认为两者都是周围神经起源的恶性肿瘤[1].它们与其它小圆形细胞恶性肿瘤的鉴别是病理诊 Peripheral neoepithelioma and Ewing’s Sarcoma are small round cell malignancies with very similar histological patterns. The former originates from the peripheral nerves, and the latter origin is unknown. However, there is a growing body of evidence that both are malignant tumors of peripheral nerve origin [1]. Their identification with other small round cell malignancies is pathological diagnosis.