The study of the value of H3F3A G34W immunohistochemical staining in the diagnosis of giant cell tumor of bone

Objective To investigate the diagnostic role of H3F3A G34W immunohistochemistry in giant cell tumor of bone. Methods A total of 275 tumors were collected from 2016 to 2018 at Shanghai Jiaotong University Affiliated Sixth People′s Hospital, including 136 giant cell tumors of bone, 31 general osteosarcomas, 3 osteoclast-rich osteosarcomas, 3 brown tumors, 34 chondroblastomas, 29 giant cell tumors of tendon sheath, 20 primary arteromatoid bone cysts and 19 non-ossifying fibromas. Results Among the 136 cases of giant cell tumor of bone,82 patients were male and 54 were female. The age ranged from 15 to 72 years (median age 38 years). Nuclear positivity for H3F3A G34W was seen in 119/136(87.5%) giant cell tumors of bone and 1/31(3.2%) general osteosarcoma,while all osteoclast-rich osteosarcomas, brown tumors, chondroblastomas, giant cell tumors of tendon sheath, primary arteromatoid bone cysts and non-ossifying fibroma were negative. Conclusions The monoclonal antibody against the G34W mutated site of H3F3A is a specific biomarker for giant cell tumor of bone and useful for the diagnosis and differential diagnosis of giant cell tumor of bone. Meanwhile,for those cases in which giant cell tumor of bone are diagnosed basing on clinical,pathologic and radiographic features but are negative for H3F3A G34W,should be tested for rare mutations or H3F3A wild type. Key words: Giant cell tumor of bone; Immunohistochemistry; Diagnosis, differential