恶性外胚层间叶瘤临床病理观察

Malignant ectomesenchymoma:a clinicopathological observation

目的报道1例罕见的发生于项背部的恶性外胚层间叶瘤。方法复习相关文献,讨论恶性外胚层间叶瘤的临床表现、组织学特征、治疗和预后。结果患儿男性,6岁。肿块组织学显示神经源标记的小圆形、卵圆形细胞和肌源标记的梭形细胞。治疗以手术切除为主,辅以化疗。结论恶性外胚层间叶瘤常发生于小儿,可能起源于外胚层、中胚层或迁徙而来的神经嵴组织。肿瘤由间叶和神经外胚层两种成分组成,需与横纹肌肉瘤、Ewing肉瘤/PNET、神经肌迷芽瘤、恶性蝾螈瘤、畸胎瘤、肾母细胞瘤及小儿腹腔内纤维组织增生性小细胞肿瘤相鉴别,综合治疗可改善预后。

Objective To report a case of malignant ectomesenchymoma that exhibit both mesenchymal and neuroectodermal elements, arising on the neck and back. Methods The clinical features, histopathologic findings, treatment and outcome were investigated in a child with a mahgnant ectomesenchymoma with review of the related literature. Results A six-year-old boy had a mass on the neck and back. The resected tumor contained small round or ovoid cells that expressed neural markers and sheets of spindled cells that expressed myogenic markers. In addition to the surgical resection, the patient was successfully treated with adjuvant chemotherapy. Conclusion Malignant ectomesenchymoma usually occurs in chldren, which may derive from ectomesenchyme, or migratory neural crest tissue capable of forming both neuroectodermal tissues and various types of mesenchymal tissues. The tumor composes of both a mesenchymal element and a neuroectodermal element. It is important to differentiate the tumor from rhabdomyosarcoma, Ewing＇ s sarcoma/PNET, teratoma, Wilms＇ tumor and intraabdominal desmeplastic small round cell tumor. Muhimodal therapy may be able to improve outcome.