Magnetic resonance imaging features of mesonephric-like adenocarcinoma of the uterine corpus in comparison with endometrial endometrioid carcinoma: Multi-institutional study
To examine magnetic resonance imaging (MRI) features of mesonephric-like adenocarcinoma (MLA) of the uterine corpus. MRI features of 19 patients with pathologically proven MLA of the uterine corpus were retrospectively compared with those of 95 patients with endometrial endometrioid carcinoma (EEC). Most patients with MLA were postmenopausal. Advanced FIGO stages were more common in the MLA than in the EEC group (63.2 % vs. 18.9 %, p < 0.001). On MRI, endophytic growth into the myometrium were more frequent in the MLA than in the EEC group (68.4 % vs. 14.7 %, p = 0.005). The median maximum tumor diameter in the MLA group (52.4 mm) tended to be larger than that in the EEC group (38.9 mm), although the difference was not statistically significant (p = 0.374). The tumor-to-muscle signal intensity ratio (SIR) on fat-suppressed gadolinium-enhanced T1-weighted gradient-echo imaging was higher in the MLA group than in the EEC group. (1.67 vs. 1.36, p = 0.002). The SIR on diffusion-weighted imaging (DWI) was comparable between the two groups (8.35 vs. 6.72, p = 0.330). The apparent diffusion coefficient value was lower in the MLA than in the EEC group (0.69 10 MRI of MLA of the uterine corpus typically demonstrates large, diffuse, and endophytic growth into the myometrium, with strong contrast enhancement and more restricted diffusion compared to EEC, with coexisting adenomyosis present in over 50% of patients. Therefore, postmenopausal women with adenomyosis should be carefully evaluated for MLA on MRI, particularly using DWI.