Efficacy Comparison and Prognostic Factor Analysis of Ultrasound‐Guided Microwave Ablation Alone Versus Combined with Lauromacrogol Sclerotherapy for Mixed Cystic‐Solid Thyroid Nodules

OBJECTIVES: To compare the therapeutic efficacy of microwave ablation (MWA) alone versus MWA combined with lauromacrogol sclerotherapy for benign mixed cystic-solid thyroid nodules. METHODS: A total of 132 pathologically confirmed benign mixed cystic-solid thyroid nodules were treated with either MWA alone (MWA group) or MWA combined with lauromacrogol sclerotherapy (MWA + LS group). Patients were followed up at 1, 3, 6, and 12 months postoperatively. The volume reduction rate (VRR) was compared between the 2 groups. Univariate and multivariate logistic regression analyses were used to assess the impact of factors such as nodule classification (based on cystic-solid morphology), cystic fluid characteristics, proportion of solid component, lauromacrogol dosage, and ablation duration on treatment efficacy. RESULTS: In this comparison of MWA without aspiration (MWA group) versus MWA with aspiration and lauromacrogol sclerotherapy (MWA + LS group), the MWA + LS group showed higher VRR at all follow-up time points (p < .05). However, because the MWA-alone group did not undergo aspiration, this difference represents the combined effect of fluid aspiration and sclerotherapy; the specific contribution of lauromacrogol cannot be determined from this study. Multivariate logistic regression identified nodule morphologic subtype as an independent predictor of treatment efficacy; the wall-nodule type achieved significantly higher VRR than the intranodular-septation type and eccentric type (p < .05). Although univariate analysis showed a negative correlation between ablation duration and postoperative VRR (p < .05), this factor was not an independent predictor in the multivariate model (p = .102), suggesting its apparent effect may be confounded by nodule complexity and other baseline characteristics. CONCLUSION: In this study comparing MWA without pre-ablation aspiration (MWA group) versus MWA with pre-ablation aspiration and lauromacrogol sclerotherapy (MWA + LS group), the combined approach was associated with higher VRR at all follow-up time points, particularly for the wall-nodule type. However, because the MWA-alone group did not undergo aspiration, the observed advantage should be interpreted as the combined effect of fluid aspiration (which removes the heat-sink effect and facilitates energy delivery) and lauromacrogol sclerotherapy, rather than as a benefit of lauromacrogol per se. The specific contribution of lauromacrogol beyond aspiration cannot be determined from this study. Shorter ablation time was associated with better postoperative outcomes in univariate analysis; though this was not an independent predictor in multivariate analysis. Future randomized controlled trials with an aspiration-plus-MWA control arm are essential to isolate the specific efficacy of lauromacrogol.