CONTRAST-ENHANCED DYNAMIC MR-IMAGING OF POSTMOLAR GESTATIONAL TROPHOBLASTIC DISEASE

Conventional spin-echo (SE) and contrast-enhanced dynamic MR imaging w ere performed on a 1.5 T superconductive unit for evaluation of myomet rial lesions in postmolar gestational trophoblastic disease (GTD) in 1 0 women. MR imaging was done at the time of the initial examination (n =10), during (n=6), and after repeated courses of chemotherapy (n=10). The T2-weighted SE image revealed an enlarged uterus (n=7), disappear ance of zonal anatomy (n=6), and heterogeneous signal intensities (n=8 ) with prominent flow voids (n=7). However, these abnormalities remain ed after repeated courses of chemotherapy, when the S-beta-HCG level r eturned to the normal range. Myometrial lesions characteristically had marked enhancement with areas of unenhancement on dynamic MR images i n patients with highly elevated S-beta-HCG. Areas of contrast enhancem ent correlated with changes in S-beta-HCG level. The enhancement was r educed with decrease in S-beta-HCG level after reheated courses of che motherapy. Six of 8 masses seen on T2-weighted images proved to be act ive trophoblastic lesions and 2 masses proved to be hematoma or necros is. In 2 patients, abnormal myometrial lesions were detected only on c ontrast-enhanced dynamic MR imaging. These preliminary data indicate t hat contrast-enhanced dynamic MR imaging more clearly demonstrates myo metrial involvement of postmolar GTD than conventional SE imaging.