Endocrine surgery · Evidence synthesis

Percutaneous ablation of parathyroid adenomas

Feasibility, effectiveness, and detailed RFA safety profile
33 source publications · 3 meta-analyses · 1 systematic review · 22 primary cohort studies
Pooled normocalcemia
85.6%
at 6–12 mo · n=815
RFA volume reduction
95.6%
at 12 mo · pooled
RFA permanent hoarseness
0.21%
95% CI 0.00–1.48
Major complications
<0.5%
all techniques
Part I · Efficacy and modality comparison
1
Section 1
Cure rate by modality
All three ablation techniques achieve comparable cure rates — no significant difference between them
RFA 90.1% · MWA 88.1% · Ethanol 77.2% · PTX 95–98% · χ²=3.22, p=0.20 · Bilgin 2025
RFA
90.1%
MWA
88.1%
Ethanol
77.2%
PTX
95–98%
2
Section 2
Modality comparison
RFA has the most favorable safety profile — lowest complication rate, best-suited for lesions near the RLN
Major Cx: RFA 0.21% · MWA 0.39% · Ethanol 0.48% · Only sig. safety difference: hoarseness χ²=8.72, p=0.01
RFA
MWA
Ethanol
Energy
RF current
Microwave
96% EtOH
Sessions
1
1
1–4
Control
Precise
Less predictable
Titratable
Major Cx
0.21%
0.39%
0.48%
RLN risk
Lowest
Higher
Leakage
Recurrence
Low
Low
Higher (MEN1)
3
Section 3
RFA vs parathyroidectomy
RFA matches PTX in cure at 12 months — no significant difference in any outcome · no incision · local anesthesia
97.1% vs 96.8% (NS) · Chai 2023 PSM n=74 · 5-yr MWA vs SR 77.2% vs 83.1% NS (Wei 2026, MWA data)
Clinical cure 12 mo
97.1%96.8% PTX
5-yr remission (MWA vs SR)
77.2%83.1% SR · Wei 2026
Procedure time
~30 min~60 min PTX
Incision
none2–7 cm PTX
Transient hypoCa (MWA vs PTX)
4.6% MWA18.4% PTX · Wei 2022
Anesthesia
LocalGeneral PTX
4
Section 4
Predictors of treatment failure
Single well-localized adenoma on concordant imaging is the strongest predictor of cure (OR 3.70)
Pre-ablation PTH ≥118 pg/mL predicts failure · Ha 2025 · Multi-nodule disease = independent risk factor
High pre-ablation PTH
≥118 pg/mL
Multiple nodules
↑ risk
Large adenoma volume
>0.96 cm³
Vitamin D deficiency
↑ risk
Elevated creatinine
↑ 5-yr risk
Multiglandular disease
↑ risk
Part II · RFA voice change — paper-by-paper evidence
5
Section 5
Per-study RFA voice change rates
PHPT voice change 2–6% across all studies — zero permanent injuries in any PHPT cohort ≥30 patients
SHPT carries 5–8× higher risk · all cases self-resolve · Bilgin 2025 pooled permanent rate: 0.21%
Study Year Cohort Rate Perm. Recovery
Chehrehgosha202460 PHPT1.7%0Transient
Ha202634 PHPT2.94%0Within 3 mo
Chai202337 PHPT2.7%01–3 mo
Qiu (PHPT)202348 PHPT4.2%0Within 3 mo
Wei202123 RFA4.3%030–180 d
Zhang (PHPT)202522 PHPT4.5%030–180 d
Liu2022132 mixed5.3%0Within 6 mo
Peng202251 PHPT5.9%0All resolved
León-Utrero202229 PHPT6.9%0Transient
Zhang (SHPT)202538 SHPT7.9%030–180 d
Khandelwal202010 PHPT10%0Transient
Qiu (SHPT)20239 SHPT33.3%0Within 3 mo
Wang*202621 PHPT57.1%*0Mean 26 min
0% 3% 6% 9% Voice change (%) Chehrehgosha 24 Ha 26 Chai 23 Qiu PHPT 23 Wei 21 Zhang PHPT 25 Liu 22 Peng 22 León 22 Zhang SHPT 25 Khandelwal 20 PHPT cluster 2–6% PHPT SHPT

*Wang 2026 (57.1%) captured intraprocedural nerve irritation in real time — mean recovery 26 min. Methodological outlier, not clinical dysphonia.

Chehrehgosha 2024
60 PHPT
1.7%
0 permanent
CIRSE grade 1 · transient
Ha 2026
34 PHPT · prospective multicenter
2.94%
0 permanent
Within 3 months
Chai 2023
37 PHPT · PSM vs PTX
2.7%
0 permanent
1–3 months
Qiu 2023 — PHPT
48 PHPT
4.2%
0 permanent
Within 3 months
Wei 2021
23 RFA arm
4.3%
0 permanent
30–180 days
Zhang 2025 — PHPT
22 PHPT · older adults
4.5%
0 permanent
30–180 days
Liu 2022
132 mixed · prospective multicenter
5.3%
0 permanent
Within 6 months
Peng 2022
51 PHPT
5.9%
0 permanent
All resolved
León-Utrero 2022
29 PHPT
6.9%
0 permanent
Transient
Zhang 2025 — SHPT
38 SHPT · multi-gland
7.9%
0 permanent
30–180 days
Khandelwal 2020
10 PHPT · small series
10%
0 permanent
Transient
Qiu 2023 — SHPT
9 SHPT · multi-gland
33.3%
0 permanent
Within 3 months
Wang 2026 ⚠
21 PHPT · continuous intra-procedural monitoring
57.1%*
0 permanent
Mean 26 min — methodological outlier

*Wang 2026 captured intraprocedural nerve irritation in real time — mean recovery 26 min, not clinical dysphonia.

6
Section 6
Pooled complication rates by modality
MWA carries 4.5× higher overall hoarseness risk than RFA — the only statistically significant safety difference
RFA 2.6% vs MWA 11.7% · χ²=8.72, p=0.01 · All permanent rates <0.5% and NS · Bilgin 2025
Nerve injury & voice change
Overall hoarseness
RFA 2.6%MWA 11.7% ↑Ethanol 4.8%PTX 3.9%Bilgin 2025
Transient voice change
RFA ~3–6%MWA ~6–25%Ethanol ~5%PTX ~3%Jeong 2025
Permanent RLN injury
RFA 0.21%MWA 0.31%Ethanol 0.48%PTX 0.4–2%Bilgin 2025
Permanent RLN — revision PTX
PTX revision up to 9%Stack et al.
SLN external branch injury
PTX ~3–7%surgical lit.
Calcium & parathyroid axis
Transient hypocalcemia
RFA 4.6–22%MWA 4.6% vs PTX 18.4%Ethanol ~2–5%PTX 18.4%Wei 2022 (MWA vs PTX)
Severe hypocalcemia
RFA 0.00%MWA 0.05% ↑Ethanol 0.00%PTX 0.10%Bilgin 2025
Transient hypoparathyroidism
MWA 33.3%Ethanol rarePTX 62.1% ↑Wei 2022 (MWA vs PTX)
Permanent hypoparathyroidism
RFA 0%MWA <0.5%Ethanol 0%PTX 0.1–2%Udelsman
Procedural & structural
Hematoma (any)
RFA 0–3%MWA 0–2%Ethanol ~5% ↑PTX 0.16–0.8%Jeong 2025
Severe hemorrhage
RFA 0.00%MWA 0.00%Ethanol 0.19%PTX 0.16%Bilgin 2025
Periglandular fibrosis
RFA minimalMWA minimalEthanol significant ↑Jeong 2025
Wound infection
RFA 0%MWA 1 caseEthanol 0%PTX ~1%Jeong 2025

Pink ↑ = highest rate within complication.

7
Section 7
Permanent voice change — pooled estimates
Permanent voice change does not differ significantly between techniques — RFA lowest at 0.21%, PTX revision up to 9%
Subgroup difference p=0.96 (NS) · All ablation techniques safer than revision PTX · Bilgin 2025
0.0% 0.3% 0.6% 0.9% 1.2% Permanent hoarseness (%) RFA (n=291)0.21% MWA (n=305)0.31% Ethanol (n=219)0.48% Parathyroidectomy0.99%

Bilgin 2025 pooled with 95% CI. PTX = Udelsman 2011 (n=1,650). Subgroup p=0.96.

Mechanism of injury

RFA
Conductive thermal spread
MWA
Dielectric; heat-sink resistant
Ethanol
Capsular leak → fibrosis
PTX
Traction, transection, cautery
Part III · Clinical translation
8
Section 8
Patient selection
Best candidates: single localized adenoma in patients who decline or are unfit for surgery
Avoid multiglandular disease, MEN, non-localizing imaging, or lesion on RLN without dissection plane

Ideal candidates

  • Single localized adenoma
  • Refusing / unfit for surgery
  • High operative risk / elderly
  • Persistent PHPT post-PTX
  • Intrathyroidal / ectopic
  • Pregnancy (bipolar RFA)
  • Cosmetic priority

Cautions / avoid

  • Multiglandular / 4-gland
  • MEN syndromes
  • Suspected carcinoma
  • Non-localizing imaging
  • Very high baseline PTH
  • Lesion on RLN, no plane
9
Section 9
RFA technique
Hydrodissection with cold D5W is the single most important maneuver to prevent nerve injury
Trans-isthmic path · local anesthesia for real-time voice monitoring · 5–7 mm active tip · 25–30 W
1
Trans-isthmic approach
Medial-to-lateral electrode path.
2
Hydrodissection
Cold D5W, ≥1 cm from RLN.
3
Polar artery first
5–7 mm tip; coagulate feeder.
4
Moving-shot
Deep-to-superficial, 25–30 W.

US practice context

Hussain et al. 2021 (UT Southwestern) reported the first US case. Kandil et al. 2023 demonstrated intrathyroidal adenoma with intraoperative PTH monitoring. Evidence base is overwhelmingly East Asian and European. Operators with established thyroid RFA expertise are well-positioned as early adopters.

Feasible
Local anesthesia · ~30 min · outpatient · translates from thyroid RFA
Effective
90.1% cure · 97.1% vs 96.8% PTX at 12 mo · PTX remains gold standard
Safe
Voice change 2–6% PHPT · permanent injury 0.21% · major Cx <0.5%
Systematic reviews & meta-analyses
Bilgin C, et al. Systematic review and meta-analysis of percutaneous ablation of parathyroid adenomas. J Clin Endocrinol Metab. 2025;110(9):e3150–e3162.
Jeong SY, et al. Efficacy and safety of radiofrequency ablation for hyperparathyroidism: meta-analysis and systematic review. Eur Radiol. 2025;35:6583–6597.
Jeong SY, et al. Complications in chemical and thermal ablation of parathyroid lesions: systematic review and meta-analysis. Eur Radiol. 2025;35:7738–7751.
Issa PP, et al. Radiofrequency ablation as a treatment modality for primary hyperparathyroidism: systematic literature review. Gland Surg. 2024;13(1):87–99.

Primary studies — RFA
Chehrehgosha H, et al. Radiofrequency ablation of parathyroid adenoma: retrospective analysis of 60 patients. Cardiovasc Intervent Radiol. 2024;47:762–770.
Ha EJ, et al. Radiofrequency ablation for primary hyperparathyroidism: multicenter non-randomized trial. Eur Radiol. 2026;36:396–405.
Chai HH, et al. Clinical and economic evaluation of ultrasound-guided RFA vs parathyroidectomy for primary hyperparathyroidism. Acad Radiol. 2023;30:2647–2656.
Qiu X, et al. Efficacy and safety of radiofrequency ablation for primary and secondary hyperparathyroidism. Sci Rep. 2023;13:16949.
Peng CZ, et al. Radiofrequency ablation for primary hyperparathyroidism and risk factors for postablative eucalcemic PTH elevation. Int J Hyperthermia. 2022;39:490–496.
Hussain I, et al. Radiofrequency ablation of parathyroid adenoma: a novel treatment option for primary hyperparathyroidism. AACE Clin Case Rep. 2021;7:e1–e4.
Kandil E, et al. Radiofrequency ablation of an intrathyroidal parathyroid adenoma with intraoperative PTH monitoring. Gland Surg. 2023;12(5):704–709.
Eldeiry LS, et al. Successful radiofrequency ablation of an intrathyroidal parathyroid adenoma after failed parathyroidectomy. AACE Clin Case Rep. 2024.
Korkusuz H, et al. Feasibility of bipolar radiofrequency ablation in patients with parathyroid adenoma: first evaluation. Int J Hyperthermia. 2018;34:1–6.
Rezvanian P, et al. Evaluation and comparison of ethanol ablation and radiofrequency ablation therapeutic effects on parathyroid adenoma. Clin Radiol. 2025. doi:10.1016/j.crad.2025.107016.

Primary studies — MWA
Wei Y, et al. Effectiveness and safety of thermal ablation for primary hyperparathyroidism: multicenter study. J Clin Endocrinol Metab. 2021;106(9):2707–2717.
Wei Y, et al. Microwave ablation versus parathyroidectomy for primary hyperparathyroidism: cohort study. Eur Radiol. 2022;32:5821–5830.
Wei Y, et al. Long-term outcomes and prognostic factors following microwave ablation vs surgical resection for primary hyperparathyroidism. Eur Radiol. 2026. doi:10.1007/s00330-025-12254-0.
Liu F, et al. Ultrasound-guided microwave and radiofrequency ablation for primary hyperparathyroidism: prospective multicenter study. Eur Radiol. 2022;32:7743–7754.
Zhang DL, et al. Microwave and radiofrequency ablation for hyperparathyroidism in older adults. Radiology. 2025;317(1):e243359.
Wang Y, et al. Thermal ablation for primary hyperparathyroidism: long-term follow-up results. Eur Radiol. 2026;36:3570–3582.
Fan BQ, et al. US-guided microwave ablation for primary hyperparathyroidism: safety and efficacy study. Eur Radiol. 2019;29:5607–5616.
Erturk MS, et al. Microwave ablation as an efficient therapy for primary hyperparathyroidism: efficacy and predictors. Int J Clin Pract. 2021;75:e14580.

Primary studies — ethanol ablation
Yazdani AA, et al. Ultrasound-guided ethanol injection for parathyroid adenoma: prospective self-controlled study. J Res Med Sci. 2020;25:3.
Yankova T, et al. Early results of percutaneous ethanol ablation in patients with primary hyperparathyroidism. Acta Med Bulg. 2022;49(1):5–11.
Stratigis S, et al. Percutaneous ethanol injection therapy: a surgery-sparing treatment for primary hyperparathyroidism. Clin Endocrinol. 2008;69:542–548.
Harman CR, et al. Indications, technique, and efficacy of alcohol injection of enlarged parathyroid glands in patients with primary hyperparathyroidism. Surgery. 1998;124:1011–1020.
Karstrup S, et al. Nonsurgical treatment of primary hyperparathyroidism with sonographically guided percutaneous injection of ethanol. AJR Am J Roentgenol. 1990;154:1087–1090.
Leong EKF, et al. Percutaneous ethanol and calcitriol injection therapy for hyperparathyroidism: single-centre experience. Front Endocrinol. 2025;16.

Surgical comparator & contextual references
Udelsman R, et al. The superiority of minimally invasive parathyroidectomy: 1650 consecutive patients with primary hyperparathyroidism. Ann Surg. 2011;253:585–591.
Tufano RP, et al. Update of radiofrequency ablation for treating benign and malignant thyroid nodules: the future is now. Front Endocrinol. 2021;12:698689.
Sim, Michelakos, 2026
Endocrine Surgery · Rush University Medical Center