软组织非典型性骨化性纤维黏液样瘤一例附文献回顾

One case report of atypical ossifying fibromyxoid tumor in soft tissue

目的:探讨非典型性或恶性骨化性纤维黏液样瘤(OFMT)的临床、病理特征,诊断及其组织学分化方向。方法:报道1例左颊部低度恶性的非典型性OFMT,从其病理形态和免疫表型,并回顾以往的文献报道,以加深对其组织学分化的认识。结果:患者女性,20岁。近发现左颊部肿胀伴疼痛。病理活检免疫组化见:CK(-),SMA(+),Vim(+),S100(-),Ki67阳性细胞数50%,P63(-),Des(-),HMB45(-),Calpdsome(+),MelanA(-)。考虑(左颊部)非典型骨化性纤维粘液样肿瘤。结论:OFMT是分化不确定的罕见肿瘤,属中间型肿瘤(偶尔转移型),其中富于细胞和/或核分裂数增多、有不规则骨样基质形成并位于肿瘤中心部,考虑为"非典型性";如有转移则为恶性。OFMT的分化方向显示出软骨样、神经及肌上皮的部分特点,基因分析提示其可能是有基因错位的肿瘤,形成凑合型的实体,有特殊的表型。

Objective. To explore the clinical and pathological characteristics of atypical/malignant ossifying fibromyxoid tulnor （OFMT） of soft tissue,as well as its diagnosis, differential diagnoses and histological differentiation. Methods ： A case of low grade atypical OFMT was reported. Results：A tumor was found in the left cheek of a 20-year-old girl. Immunohistochemical study showed that the tumor cells were positive for vimentin and SMA protein and negative for CK ,S100 and P63 protein. Conclusions. OFMT is a rare soft tissue tumor with uncertain differentiation which belongs to intermediate malignancy category （rarely metastasizing）. OFMT, showing hypercellular and/or having increased numbers of mitotic figures and deposition of osteoid randomly ,often within the center of the lesion, is regarded as atypical variant , and malignant one if that metastasizes. It has been suggested that OFMT has chondroid schwannian and myoepithelial differentiation, however, genetic analysis proposes that it might belong to translocation-associated sarcoma forming a ＂Scrambled entity＂ with a unique phenotype.