MRI appearance of gestational choriocarcinoma within the myometrium

Magnetic resonance imaging in patients with gestational trophoblastic disease

RATIONALE AND OBJECTIVES

The authors describe the magnetic resonance (MR) imaging characteristics in patients with gestational trophoblastic disease (GTD) before and after therapy and to correlate these findings with human gonadotropin levels and the specific histology of GTD.

METHODS

Thirteen women (mean age, 30.1 years) with elevated human chorionic gonadotropin (HCG) levels and histologically proven GTD underwent MR examinations of the pelvis. Magnetic resonance imaging was performed on a 1.5-tesla unit. Axial and sagittal proton density-weighted and T2-weighted and sagittal T1-weighted sequences were obtained. Four patients underwent follow-up studies after 4 and 8 weeks to monitor the response to therapy. Gestational trophoblastic disease was histologically proven with curettage in 11 patients and with hysterectomy in two cases.

RESULTS

Nine patients had a diffusely enlarged uterus with pathologic signal intensities. In four patients, a focal tumor mass was observed. All patients showed loss of the zonal anatomy of the uterus in at least one local area. In 11 patients, no uterus zones could be identified throughout the entire uterus. Pathologic dilated tumor vessels were evident in all patients. In all four cases in which follow-up imaging studies were obtained, uterus size, signal intensities, identification of uterus zones, and uterus vessels returned to normal.

CONCLUSION

Magnetic resonance imaging shows trophoblastic tumor infiltration as diffuse uterus enlargement, focal tumor masses, loss of zonal anatomy of the uterus, and pathologic uterine vasculature; this seems to be the most reliable MR imaging finding in patients with GTD. No correlation was found between MR imaging changes and HCG levels or specific histologic types of GTD.