Diagnostic possibility of diffusion tensor imaging for the evaluation of myometrial invasion in endometrial cancer: An ex vivo study

Purpose: To investigate the feasibility of magnetic resonance imaging (MRI) diffusion tensor imaging (DTI) for evaluating the myometrial invasion of uterine endometrial cancer. Materials and Methods: Twelve specimens of uterine endometrial cancer were obtained. The depth of myometrial invasion was classified as stage E (limited to the endometrium; n = 4), stage S (superficial invasion of less than 50% of the myometrium; n = 5), or stage D (deep invasion of greater than 50% of the myometrium; n = 3). The specimens were fixed in 10% formalin and stored at 4°C before imaging. At 15 hours after fixation, MRI was performed using a 4.7‐T experimental imager/spectrometer system. Results: We found a high fractional anisotropy (FA) value zone (anisotropic zone) at the myometrium adjacent to the tumor on FA maps of histopathological stage S and stage D cancers, whereas the anisotropic zone did not exist in stage E cancers. Histopathological analysis showed that compared to the other regions, the anisotropic zone had tightly packed stromal tissue. The disruption of the anisotropic zone was consistent with myometrial invasion. Conclusion: Our ex vivo study suggests that DTI might be a useful tool for the diagnosis of myometrial invasion of uterine endometrial cancer ex vivo. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.