To evaluate an optimized MR-guided Focused Ultrasound Surgery (MRgFUS) protocol for treatment of symptomatic uterine fibroids.

One hundred and forty-seven women with symptomatic fibroids were treated in a prospective clinical trial performed at 5 centers. Ninety-six consecutive patients were treated under the original pivotal study (A) protocol, and 51 were subsequently treated under an optimized (B) protocol. Protocol A allowed a maximum (max) fibroid treatment volume of 100ccs (33% of total fibroid volume), whereas protocol B allowed a max treatment volume of 150ccs (33% of total volume in subserosal fibroids; 50% of volume in non-subserosal fibroids). Therapeutic sonications were delivered with a MRgFUS system (ExAblate 2000, InSightec Inc.). Temperature-sensitive MR imaging was performed during the sonication to monitor thermal spot localization and temperature. Treatment outcomes were assesed by the standardized Uterine Fibroid Symptoms and Quality of Life (UFS-QOL) questionnaire and the frequency of adverse events (AEs). UFS-QOL scores were obtained at baseline, 3, 6 and 12 months post-treatment. Frequency of AEs was recorded up to 6 months post-treatment. Statistical methods included Student’s t-test.

The mean±SD UFS-QOL scores (points) were: 62.1±15.8 at baseline, and progressively decreased to 35±19.9 at 3 months (p< 0.0001), 33.1±20.9 at 6 months (p< 0.0001), and 33.2±21.5 at 12 months (p< 0.0001). Early results demonstrate that women treated under protocol B vs. protocol A had a greater decrease in UFS-QOL score (31.2±2 vs. 38.02±20, p=0.03). The number of AEs reported had decreased from 2.5/patient in protocol A to 1.7/patient in protocol B. No serious adverse events were recorded.

MRgFUS is an efficacious method of uterine fibroid treatment resulting in significant symptomatic improvement at 3 and 6 months, that is sustained at 1 year post-treatment. Early reports of the optimized protocol demonstrate even greater clinical efficacy and less reports of AEs.

F.M.F.,M.J.S.,G.K.H.,K.H.H.,E.A.S.,C.M.T.,N.J.M.,F.A.J.,F.J.R.: Clinical trial co-investigators and consultants to Insightec Inc., Haifa, Israel. No financial affiliations with company.
M.J.S.,F.A.J.: NIH 5R25 CA089017
F.A.J.: NIH P01 CA67165
K.H.H.: NIH R01 CA046627