Value of enhanced t1 mapping MR imaging in the evaluation of the depth of myometrial invasion in endometrial cancer: compared with dynamic contrast-enhanced MR imaging
Author Block: X. Liu, Z. Yuan, Y. Li, J. Ren, Y. He, H. Xue, Z. Jin; Beijing/CN
Purpose: To compare the diagnostic efficiency of enhanced T1 mapping MR imaging and dynamic contrast-enhanced (DCE) imaging for assessing the depth of myometrial invasion in patients with endometrial cancer.
Methods or Background: 46 women diagnosed with endometrial cancer underwent preoperative MR imaging. Two radiologists independently assessed the depth of myometrial invasion, categorized as no myometrial invasion, superficial myometrial invasion, or deep myometrial invasion, on T2WI+DWI+DCE MR imaging, followed by T2WI+DWI+enhanced T1 mapping MR imaging, four weeks later. The findings were then compared to histopathological examinations. The diagnostic performance comparison was conducted using the chi-square test.
Results or Findings: The overall accuracy for accessing depth of myometrial invasion on T2WI+DW+DCE and T2WI+DW+enhanced T1 mapping were 76.1%, 80.4% for reader 1, and 78.3%, 80.4% for reader 2, respectively. The increment was not statistically significant for either reader. While assessing the absence of myometrial invasion, the precision, sensitivity, and specificity achieved by both radiologists using DCE were 100%, 16.7%, and 100%, whereas for enhanced T1 mapping the precisions were 100%, with sensitivities of 50% and 33%, and specificities of 100%. In evaluating superficial myometrial invasion, these values using DCE were 82.4%/82.8%, 84.8%/87.9%, and 53.8%; using enhanced T1 mapping, these values were 87.5%/85.3%, 84.8%/87.9%, and 69.2%/61.5%. Assessment of deep myometrial invasion achieved these values of 54.5%/60%, 85.7%, and 87.2%/89.7% with DCE; 54.5%/60%, 85.7%, 87.2%/89.7% with enhanced T1 mapping. Inter-reader agreement, measured with kappa values, was 0.831 with DCE-MRI and 0.899 with enhanced T1 mapping. Both radiologists concurred that enhanced T1 mapping substantially improved diagnostic confidence over DCE-MRI.
Conclusion: Enhanced T1 mapping demonstrates superior diagnostic efficiency in the evaluation of myometrial invasion in endometrial cancer compared with DCE MR imaging.
Limitations: This was a pilot study with a small sample size.
Funding for this study: This work was supported by grants from Natural Science Foundation of China (grant No. 82271886).
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This retrospective study was approved by the institutional review board, which waived the requirement of informed consent.