Uterine and Fibroid Imaging Analysis from the FIRSTT Study

Area of Science:

• Medical Imaging
• Interventional Radiology
• Gynecologic Surgery

Background:

• Uterine fibroids significantly impact women's health, with many preferring uterine-preserving treatments over hysterectomy.
• Nonsurgical treatment options for uterine fibroids have limited imaging-defined endpoints.
• The FIRSTT trial compared uterine artery embolization (UAE) and magnetic resonance imaging-guided focused ultrasound surgery (MRgFUS) for symptomatic fibroids.

Purpose of the Study:

• To compare imaging outcomes up to 36 months post-treatment for UAE and MRgFUS in women with symptomatic uterine fibroids.
• To evaluate fibroid and uterine volume reduction, and nonperfused volume following UAE and MRgFUS.
• To provide imaging-defined endpoints for nonsurgical uterine fibroid treatments.

Main Methods:

• Subanalysis of the FIRSTT randomized controlled trial involving premenopausal women with symptomatic uterine fibroids.
• Magnetic resonance imaging (MRI) performed at baseline and up to 36 months post-treatment.
• Key outcomes included total fibroid load reduction, largest fibroid volume reduction, uterine volume reduction, and nonperfused volume.

Main Results:

• Median total fibroid load reduction was approximately 50% at 24 and 36 months in both UAE and MRgFUS arms.
• While MRgFUS showed a greater decrease in the largest fibroid volume, UAE demonstrated a larger reduction in uterine volume (neither statistically significant).
• At 24 months, nonperfused volume was significantly higher in the UAE arm (92%) compared to the MRgFUS arm (10%).

Conclusions:

• Both UAE and MRgFUS achieve comparable fibroid volume reduction in the long term.
• UAE leads to a higher nonperfused fibroid volume at 24 months compared to MRgFUS.
• Imaging endpoints provide valuable data for comparing nonsurgical uterine fibroid interventions.