Factors associated with early complete resolution after radiofrequency ablation for low-risk papillary thyroid microcarcinoma: a dual-center retrospective study

Yuxuan Qiu; Yina Zhang; Jingqi Zhu; Yun Gong; Lu Yin; Pin Fan; Lian Zhang; Lingyun Bao; Jianhua Fang; Jun Lou; Chenke Xu

doi:10.1007/s00330-026-12415-9

Factors associated with early complete resolution after radiofrequency ablation for low-risk papillary thyroid microcarcinoma: a dual-center retrospective study

Eur Radiol. 2026 Mar 6. doi: 10.1007/s00330-026-12415-9. Online ahead of print.

Authors

Yuxuan Qiu¹, Yina Zhang², Jingqi Zhu², Yun Gong³, Lu Yin², Pin Fan², Lian Zhang², Lingyun Bao¹, Jianhua Fang¹, Jun Lou⁴, Chenke Xu⁵

Affiliations

¹ Department of Ultrasound, Affiliated Hangzhou First People's Hospital, School of Medicine, Westlake University, Hangzhou, China.
² Department of Ultrasound, Hangzhou Cancer Hospital, Hangzhou, China.
³ Department of Pediatrics, Affiliated Hangzhou First People's Hospital, School of Medicine, Westlake University, Hangzhou, China.
⁴ Department of Ultrasound, Hangzhou Cancer Hospital, Hangzhou, China. loujun173676162@163.com.
⁵ Department of Ultrasound, Affiliated Hangzhou First People's Hospital, School of Medicine, Westlake University, Hangzhou, China. muerxck@163.com.

PMID: 41792573
DOI: 10.1007/s00330-026-12415-9

Abstract

Objectives: To identify predictors of early complete ablation zone resolution (within 1 year) after radiofrequency ablation (RFA) for low-risk papillary thyroid microcarcinoma (PTMC).

Materials and methods: A retrospective dual-center study enrolled 225 patients with low-risk PTMC (2017-2022). Ablation zone volume was tracked during follow-up, with the specific time of complete resolution modeled using exponential decay functions. Multivariable Cox regression and restricted cubic spline (RCS) analyses identified independent predictors of resolution.

Results: Cumulative complete resolution rates were 62.2% at 1 year and 98.7% at 2 years. Independent predictors of complete resolution within 1 year included normal thyroglobulin antibody (TgAb) levels (hazard ratio (HR): 2.64, 95% confidence Interval (CI): 1.38-5.07) and thyroid peroxidase antibody (TPOAb) levels (HR: 1.92, 95% CI: 1.34-2.75), nodule diameter ≤ 5 mm (HR: 1.53, 95% CI: 1.02-2.29), and absence of intratumoral vascularity (HR: 2.77, 95% CI: 1.83-4.21). Energy density showed an inverted U-shaped relationship with resolution probability within 1 year (p < 0.001 for non-linearity).

Conclusion: RFA achieves favorable long-term efficacy for low-risk PTMC, and complete resolution within 1 year is predictable by normal TgAb/TPOAb, smaller nodule size, absence of intratumoral vascularity, and moderate energy density. These findings may provide valuable insights for refining RFA techniques and the development of personalized follow-up.

Key points: Question Predicting early complete resolution of low-risk PTMC after RFA is critical to mitigate concerns about treatment outcomes and optimize follow-up. Findings Normal TgAb/TPOAb, smaller nodule size, absence of intratumoral vascularity, and moderate energy density independently predict early complete ablation zone resolution within 1 year after RFA. Clinical relevance Identifying predictors of early resolution enables optimized RFA energy delivery and pretreatment decision-making. This provides doctors and patients with evidence-based guidance to refine ablation strategies and personalize management plans.

Keywords: Radiofrequency ablation; Thyroid carcinoma; Ultrasonography.

Abstract

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