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Ultrasound-guided percutaneous microwave ablation for uterine fibroids: mid-term local treatment efficiency and associated influencing factors.

OBJECTIVE
To investigate the mid-term local treatment efficiency of ultrasound (US)-guided percutaneous microwave ablation (MWA) for uterine fibroids (UFs) and the associated influencing factors.


METHODS
From July 2020 to October 2021, a total of 28 patients with 52 UFs who had undergone US-guided MWA were retrospectively included in this study. Pretreatment clinical characteristics, conventional US and contrast-enhanced ultrasound (CEUS) features were analyzed to explore their correlation with volume reduction ratios (VRRs) of sufficient ablation (i.e., a volume reduction ratio (VRR) of at least 50% at the 3 month follow-up). The patients were assessed at 1-, 3-, 6 month follow-up after MWA treatment and the assessment included VRR, adverse events, uterine fibroid symptom (UFS) and quality of life (QoL) scores, and clinical symptoms.


RESULTS
The procedures of percutaneous MWA for UFs were tolerated well and no major complications occurred in all patients. At the 1-, 3-, 6 month follow-up, the median VRRs of UFs were 30.1%, 46.9%, and 65.8%, respectively. At the 3 month follow-up, 44.4% of fibroids obtained sufficient ablation while the remaining 55.6% obtained partial ablation (i.e., a VRR of <50%). Non-enhancing area during the early phase (i.e., within 30 sec after injecting contrast agent) on pretreatment CEUS was present in 22.2% UFs, which was associated with sufficient ablation at the 3 month follow-up (p < 0.05). In addition, the relevant clinical symptoms of all patients were alleviated or removed. The UFS and QoL score after MWA decreased significantly in comparison with those after MWA (p = 0.04 and p = 0.057, respectively), indicating a remarkable improvement of clinical symptom and QoL.


CONCLUSION
US-guided MWA is an effective and safe method to treat patients with UFs. Non-enhancing area during the early phase on pretreatment CEUS is associated with mid-term local treatment efficiency, which might be used to predict treatment outcome.


ADVANCES IN KNOWLEDGE
Non-enhancing area during the early phase on pretreatment CEUS is an important factor associated with mid-term local treatment efficiency. This is the first study finding that CEUS feature can be used as a marker for the prediction of mid-term local treatment response.