Can amide proton transfer-weighted imaging differentiate tumor grade and predict Ki-67 proliferation status of meningioma?

Abstract

Objectives:

To determine the utility of the amide proton transfer-weighted MR imaging in differentiating the WHO grade and predict proliferative activity of meningioma.

Methods:

Fifty-three patients with WHO grade I meningiomas and twenty-six patients with WHO grade II meningiomas underwent conventional and APT-weighted sequences on a 3.0 Tesla MR before clinical intervention. The APT-weighted (APTw) parameters in the solid tumor region were obtained and compared between two grades using the t-test, the receiver operating characteristic (ROC) curve was used to assess the best parameter for predicting the grade of meningiomas. Pearson’s correlation coefficient was calculated between the APTw _max and Ki-67 labeling index in meningiomas.

Results:

The APTw _max and APTw _mean values were not significantly different between WHO grade I and grade II meningiomas ( P=0.103 and P=0.318). The APTw _min value was higher and the APTw _max-mim value was lower in WHO grade II meningiomas than in WHO grade I tumors. ( P=0.027 and P=0.019). But the APTw _min was higher and the APTw _max-min was lower in microcystic meningiomas than in WHO grade II meningiomas( P= 0.001 and P=0.006). The APTw _min combined with APTw _max-min showed the best diagnostic performance in predicting the grade of meningiomas with an AUC of 0.772. The APTw _max value was positively correlated with Ki-67 labeling index (r=0.817, P<0.00l) in meningiomas, the regression equation for the Ki-67 labeling index (%) (Y) and APTw _max (%)(X) was Y=4.9×X-12.4 (R ² =0.667, P< 0.001).

Conclusion:

As a noninvasive imaging method, the ability of APTw-MR imaging in differentiating the grade of meningiomas is limited, but the technology can be used to predict the proliferative activity of meningioma.