骨外尤因肉瘤(EES)是一种罕见的软组织肿瘤,主要在青少年和年轻人中观察到。并以攻击性行为为特征。到目前为止,文献中仅报道了2例原发性腋窝软组织EES。其中一位是一名29岁的女性患者,她的左腋下有一个肿块。经检查,一个不规则的,无痛肿块,5厘米×5厘米×3厘米,在左腋下注意到。组织病理学检查显示肿块很小,圆形,细胞质很少的蓝色细胞,圆形原子核,许多有丝分裂,和坏死。免疫组织化学(IHC)检查CD99阳性,ER阴性,PR,Her2neu,CK7,CK5/6,CD56,CD45,CK-pan,CKHMW,P63,desmin,S100,TdT,波形蛋白,Myogenin,突触素,患者被诊断为原发性腋窝软组织EES,并开始接受新辅助化疗。十二个月后,她在临床上没有这种疾病。
Extraskeletal Ewing\'s sarcoma (EES) is a rare soft tissue tumor predominantly observed in adolescents and young adults, and is characterized by aggressive behavior. So far, only two cases of primary axillary soft tissue EES have been reported in the literature. One of them was a 29-year-old female patient who presented with a lump in her left axilla. Upon examination, an irregular, painless mass, measuring 5 cm × 5 cm × 3 cm, was noted in the left axilla. A histopathological examination of the mass revealed small, round, blue cells with scant cytoplasm, round nuclei, numerous mitosis, and necrosis. An immunohistochemistry (IHC) examination was positive for CD99 and negative for ER, PR, Her2neu, CK7, CK5/6, CD56, CD45, CK-pan, CKHMW, P63, desmin, S100, TdT, vimentin,
myogenin, synaptophysin, and chromogranin A. The patient was diagnosed with primary axillary soft tissue EES and was started on neoadjuvant chemotherapy. Twelve months later, she is clinically free from the disease.