Occurrence and Risk Factors for Perioperative Treatment Discontinuation during Magnetic Resonance-Guided High-Intensity Focused Ultrasound (MR-HIFU) Therapy in Symptomatic Uterine Fibroids-A Retrospective Case-Control Study

Background: The main aim of our study involves the analysis of reasons and risk factors for perioperative treatment discontinuation in patients with symptomatic uterine fibroids (UFs) who were qualified for magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) and in whom the procedure was discontinued. Methods: The presented research included 372 women who were primarily eligible for MR-HIFU, but the procedure was interrupted. The reasons and risk factors for treatment discontinuation were analyzed. A statistical comparison of two cohorts (patients in whom the treatment was discontinued and completed) was conducted based on epidemiological factors, UF characteristics and the implementation of uterotonics. Results: The mean discontinuation rate was 18.28% (n = 68). The main reason was the malposition of the intestines (52.94% of all cases). The thermoablation of subserosal UFs was a statistically significant risk factor of perioperative treatment discontinuation (OR 4.62, CI 95% 2.04-10.56), while the therapy of intramural UFs considerably decreased the risk (OR 0.21, CI 95% 0.08-0.51). The volume of the targeted UF was negatively correlated with the risk of discontinuation (OR 0.991, CI 95% 0.986-0.996). Augmentation with oxytocin, but not misoprostol, during the procedure significantly decreased the risk of potential discontinuation (OR 0.15, CI 95% 0.045-0.387, p < 0.001). Conclusion: Although the discontinuation rate seems to be relatively low, further prospective randomized trials are needed to confirm our results. The establishment of particular eligibility criteria for the treatment is a crucial issue in this area. Resigning from the procedure in cases at a high risk of discontinuation might increase patient safety and shorten the time to introduce the most appropriate therapy.