Tumor immunohistochemistry and preoperative magnetic resonance imaging features predict local recurrence of giant cell tumor of bone following intralesional curettage.

Giant cell tumor of bone (GCTB) is among the most prevalent types of tumor of the bone in East and Southeast Asia. The high rate of local recurrence following intralesional curettage poses a challenge for the clinical treatment of GCTB. In the present study, the expression of matrix metalloproteinase-9 (MMP-9), vascular endothelial growth factor (VEGF), receptor activator of nuclear factor-κB (RANK) and RANK ligand (RANKL) in GCTB was investigated by immunohistochemical staining. A correlation between expression and preoperative magnetic resonance imaging (MRI) features was identified. The patients were followed up for ≥2 years after intralesional curettage. The rates of local recurrence were compared among different groups. A total of 74 cases of GCTB in the proximal tibia or distal femur were investigated. MRI features were retrospectively examined by correlation analysis. The expression of MMP-9 was demonstrated to be associated with cystic changes and the 'paint brush borders' sign (P<0.05), and positively associated with the expression of RANKL (P<0.05) and VEGF (P<0.05). Cystic changes, the 'paint brush borders' sign and adjacent soft tissue invasion were associated with high rates of local recurrence (P<0.05) and were therefore identified as significant risk factors. Pathologically, the 'paint brush borders' sign was demonstrated to be indicative of local invasion of the bone. These findings may be useful for predicting local recurrence of GCTB, and may provide important insight into the preoperative MRI features and molecular expression patterns of GCTB tumors.