MR imaging in symptomatic tamoxifen-treated patients

Purpose. To assess the MR imaging (MRI) findings in symptomatic tamoxifen treated-women with abnormal transvaginal sonography. Patients and Methods. From january 1997 to june 2000, 32 consecutive symptomatic tamoxifen treated-women with abnormal transvaginal sonography were prospectively studied by MRI. T1-weighted, T2-weighted, post-contrast T1-weigthed and dynamic gradient-echo T1-weighted sequences were used. All patients underwent uterine sampling within one month of MRI. Results. Endometrial thickness at sonography ranged from 5 to 48 mm (mean thickness 19 mm), and on T2-weighted imaging ranged from 3 to 50 mm (mean = 25 mm). Three MRI patterns were found. Pattern 1 (13 patients) was defined as homogeneous high signal intensity of the endometrium on T2W images, and signal void in the lumen on gadolinium-enhanced images. Pattern 2 (8 patients) was defined as heterogeneous endometrial signal on T2W images, and latticelike enhancement traversing the endometrial canal on gadolinium-enhanced images. Pattern 3 (11 patients) was defined as heterogeneous signal on T2W images with masses or nodules which were better seen on dynamic gadolinium-enhanced images. In pattern 1 we found 13 atrophic endometrium, in addition there were 4 polypoid glandulo-cystic proliferation (PGCP), and 1 adenomyosis. In pattern 2 we found 3 PGCP, 4 atrophy and 1 polyp without hyperplasia. The 2 carcinomas and the polyps with hyperplasia were found in pattern 3 (11 patients). Conclusion. In our experience MRI allows differentiation of lesions which may require surgery from other lesions in which noninvasive follow-up is possible.