长骨骨纤维结构不良型釉质上皮瘤临床病理分析

Osteofibrous dysplasia-like adamantinoma of long bone:A clinicopathologic analysis

目的探讨长骨骨纤维结构不良型釉质上皮瘤的临床病理特点、鉴别诊断及生物学特征。方法对2例长骨骨纤维结构不良型釉质上皮瘤进行病理学、免疫组织化学观察,结合临床资料进行分析并复习相关文献。结果2例长骨骨纤维结构不良型釉质上皮瘤患者均为年轻人,临床以小腿疼痛或无痛性肿胀为主,病程较长,影像学均示胫骨骨干病变。光镜下肿瘤主要由梭形细胞和散在的新生编织骨组成,梭形细胞密度较高,呈束状或编织状排列,纤维组织间见少数巢团状或裂隙状的上皮样细胞巢,梭形细胞和上皮样细胞均无明显异型性。免疫表型:上皮细胞巢表达CKpan、CK14和CK19,但不表达CK8、CK18。EGFR阳性表达主要见于上皮样细胞,Ki-67在上皮样细胞和梭形细胞均有少量散在阳性表达。结论长骨骨纤维不良型釉质上皮瘤是一种罕见的好发于年轻人胫骨骨干的低度恶性肿瘤,主要根据影像学、光镜及免疫组化确诊,应与骨纤维结构不良、转移癌、滑膜肉瘤等相鉴别。

Purpose To investigate the clinicopathologic features, biological behavior of osteofibrous dysplasia-like adamantinoma of long bone and its differentiated diagnosis. Methods Two cases of osteofibrous dysplasia-like adamantinoma of long bone were observed by HE and immunohistochemicai staining and their clinical features analyzed. Results Two cases of osteofibrous dysplasia-like adamantinoma of long bone were located at the mid-shaft of the tibia of younger patients by X ray examination. The patients were presented with focal swelling with or without pain for several years. Histologically, the neoplasm was composed of cdlular spindle cells admixed with woven bone spicules and several irregular epithelial nests. The spindle cells were arranged in bundles with focal areas showing storiform pattern. Prominent atypia was not found in both spindle cells and epithelial cells. Immunohistochemically, the epithelial cell nests were positive for CKpan, CK14 and CK19, but negative for CK8 and CK18. EGFR was mainly expressed in epithelial cells. Ki-67 was sparsely positive in the neoplasm. Conclusions The osteofibrous dysplasia-like adamantinoma of long bone is a rare lowgrade primary malignant tumor of long bone with a strong predilection for involvement of the mid-shaft of the tibia primarily occurring in children and younger. The diagnosis of this tumor is dependent on imaging, microscopy and immunohistochemicai staining. It should be distinguished from osteofibrous dysplasia, metastatic carcinoma and synoviai sarcoma.