骨原发性巨细胞血管母细胞瘤临床病理学观察

Primary giant cell angioblastoma of bone:a clinicopathological study

目的探讨骨原发性巨细胞血管母细胞瘤（giant cell angioblastoma,GCAB）的临床特点、影像学表现、病理学形态、免疫表型及其鉴别诊断。方法对3例骨原发性GCAB的临床资料、影像学表现、病理学形态和免疫表型进行回顾性分析。结果2例为成年女性,1例为男童。病变分别位于第2腰椎、左股骨远端和左手第3~5掌骨。患者均以局部骨疼痛就诊,其中2例伴活动受限,2例伴周围软组织肿胀。影像学显示为骨质破坏,2例累及邻近软组织。低倍镜下见组织由丛状增生的不规则形血管瘤样结节组成,结节之间为纤维结缔组织。高倍镜下,血管瘤样结节由增生的小血管和周围的胖梭形周皮细胞组成,后者可呈同心圆状围绕小血管,结节内可见散在的破骨样巨细胞。免疫表型：结节内小血管内皮细胞表达CD31和CD34,其周围的周皮细胞表达α-SMA和vimentin,破骨样巨细胞表达KP-1。结论 GCAB属于局部侵袭性的中间型血管内皮瘤。除周围软组织外,少数病例可原发于骨内,并可发生于成人。GCAB需与慢性肉芽肿性炎症、丛状纤维组织细胞瘤、簇状血管瘤和卡波西型血管内皮瘤等鉴别。

Purpose To analyze the clinicopathological characteristics of giant cell angioblastoma（ GCAB） presenting primarily in the bone. The differential diagnosis is discussed. Methods The clinical,radiological and histopathological profiles in three cases of bony GCAB were reviewed. Results The tumor occurred in two adult females and one boy. The lesion involved the second vertebrae,left distal femur and 3rd to 5th left metacarpal bones in one case each. Clinically,all three patients presented with bone pain. Two patients were accompanied with restricted mobility. Radiological examination showed bone destruction with involvement of adjacent soft tissue in two cases. Histologically,the tumor was composed of irregular angiomatoid nodules which showed striking plexiform architecture. On high power,the nodules were composed of small vessels surrounded by proliferative oval-to-spindled pericytes which showed concentric aggregation around the vascular channels. The hallmark of the lesion was the presence of multinucleated osteoclast-like giant cells scattered within the nodules. By immunohistochemistry,the endothelial cells were positive for CD31 and CD34,whereas the surrounding pericytes were positive for alpha smooth muscle actin and vimentin. CD68 staining highlighted the osteoclast-like giant cells. Conclusions GCAB is a distinctive vascular tumor of intermediate malignancy characterize by local aggressiveness. On rare occasions,GCAB may occur in adult patients and manifest as primary bone lesions. Awareness of its characteristic features will help in the distinction from a variety of disease including granulomatous lesions,plexiform fibrous histiocytoma,tufted hemangioma and Kaposiform hemangioendothelioma.