Rabbit VX2 tumors as an animal model of uterine fibroids and for uterine artery embolization

PURPOSE: To determine the suitability of the rabbit VX2 tumor animal model for uterine fibroids and uterine artery embolization (UAE). MATERIALS AND METHODS: The authors implanted and grew one uterine VX2 tumor per rabbit in six rabbits. UAE was performed by using 100-300 mu m embolic particles and confirmed with x-ray digital subtraction, angiography, magnetic resonance (MR) imaging, and necropsy. Unenhanced and contrast medium-enhanced MR images of VX2 tumors were obtained before and after UAE. Relative MR signal-to noise-ratio (SNR) was measured in the uterine VX2 tumor and in normal uterine tissue before and after UAE and compared by using a paired t-test (P =.05). RESULTS: VX2 uterine tumors were successfully grown, and both VX2 tumor presence in the uterus and UAE were seen angiographically and confirmed with necropsy in all six rabbits. Statistically significant reductions in relative SNRs were measured in tumors (SNR before UAE, 15.3 +/- 5.15; SNR after UAE, 3.84 +/- 3.94; P <.0001). No statistically significant decrease in SNR was measured in normal uterine tissue before and after UAE (P =.63 for the right uterine horn and P =.93 for the left uterine horn). CONCLUSION: Rabbit VX2 uterine tumors may be a suitable animal model of uterine fibroids and UAE.