Triple-phase dynamic MRI: a new clue to predict malignant transformation of giant cell tumor of bone.
OBJECTIVE
Our purpose was, through the comparison of the characteristics of time-intensity curve on triple-phase dynamic contrast-enhanced MRI among groups of giant cell tumor of bone (GCTB), recurrent benign giant cell tumor of bone (RBGCTB), and secondary malignant giant cell tumor of bone (SMGCTB), to find clues to predict the malignant transformation of GCTB.


METHODS
21 patients diagnosed as GCTB were included in this study. All cases took recurrence after intralesional curettage. 9 cases were confirmed as SMGCTB and 12 cases were confirmed as RBGCTB. Cases were divided into four groups: group A, GCTB (n=9); group B, SMGCTB (n=9); group C, GCTB (n=12); group D, RBGCTB (n=12). Enhancement index(EI) of lesions on DCEMRI was calculated using formula: EI(t)=[S(t)-S(0)]/S(0), where S(0) was signal intensity of lesion on non-contrast-enhanced T1-weighted images and S(t) was signal intensity of lesion on DCEMRI (t=30, 60, 180s). Enhancement index of each group in each phase was compared using One-Way ANOVA analysis. Slope values of time-intensity curve were compared by the same way.


RESULTS
Time-intensity curve of SMGCTB was characterized by a steep upward slope followed by an early and rapid washout phase. Time-intensity curve of GCTB and RBGCTB was characterized by a steep slope followed by a relatively slow washout phase. No significant difference in enhancement index was found in the first phase (p>0.05). There was significant difference in the second and the third phase (p<0.05). Enhancement index of group B (SMGCTB) was smaller. There was no difference in rising slope value (p>0.05).


CONCLUSIONS
Dynamic contrast-enhanced MRI appears a helpful method to find new clues to predict malignant transformation of GCTB.
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197, Ruijin 2nd Road, Shanghai 200025, China; Department of Radiology, Yueyang Hospital, Shanghai University of Traditional Chinese Medicine, No.110, Ganhe Road, Shanghai 200437, China. Electronic address: chenliang0106@yahoo.com.cn.
Liang
L
Chen
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197, Ruijin 2nd Road, Shanghai 200025, China. Electronic address: dingxiaoyi@hotmail.com.
Xiao-Yi
XY
Ding
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197, Ruijin 2nd Road, Shanghai 200025, China. Electronic address: wangchsh@sina.cn.
Cheng-Sheng
CS
Wang
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197, Ruijin 2nd Road, Shanghai 200025, China. Electronic address: smjsh@hotmail.com.
Ming-Jue
MJ
Si
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197, Ruijin 2nd Road, Shanghai 200025, China. Electronic address: lianjundu@yahoo.com.cn.
Lian-Jun
LJ
Du
Department of Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No.197, Ruijin 2nd Road, Shanghai 200025, China. Electronic address: ly10936@rih.com.cn.
Yong
Y
Lu
D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000473:pathology*; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
Dynamic contrast-enhanced MRI; Giant cell tumor of bone; Malignancy