Primary giant cell angioblastoma of bone:a clinicopathological study / 临床与实验病理学杂志

ABSTRACT

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 scat-tered 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. Conclu-sions 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 heman-gioendothelioma.