Preoperative risk stratification in women with endometrial cancer: A comparison of contrast-enhanced MR imaging and diffusion-weighted MR imaging

Purpose: To compare CE MRI and DWI in the risk stratification of women with endometrial cancer for lymph node metastasis. Method: Two readers independently assessed the degree of myometrial invasion on two separate occasions in a retrospective cohort of 84 women with endometrial cancers: once with CE MRI and standard anatomic sequences and another time with DWI and standard anatomic sequences. Participants were stratified according to their risk of lymph node metastasis following the European Society for Medical Oncology guidelines. The rate of lymph node metastasis was compared between the risk stratification groups obtained using CE MRI or DWI by generalized estimating equations. Results: In the low-risk group, the rate of lymph node metastasis was 1.9% (1/53) when using CE MRI and 1.9% (1/54) when using DWI for reader 1, and 3.8% (2/52) when using CE MRI and 1.9% (1/52) when using DWI for reader 2. The rate of lymph node metastasis in the high-risk group was 25.8% (8/31) when using CE MRI and 26.7% (8/30) when using DWI for reader 1, and 21.9% (7/32) when using CE MRI and 25.0% (8/32) when using DWI for reader 2. There was no significant difference between CE MRI and DWI in the rate of lymph node metastasis according to the risk stratification (p > .05 in both low- and high-risk groups for both readers). Conclusion: DWI might be a comparable alternative to CE MRI in the preoperative risk stratification of women with endometrial cancer for lymph node metastasis.