US-Guided Percutaneous Microwave Ablation for Primary Hyperparathyroidism with Parathyroid Nodules: Feasibility and Safety Study

Purpose: To test the feasibility, safety, and efficacy of microwave (MW) ablation for primary hyperparathyroidism (pHPT) in patients who are unsuited or unwilling to undergo surgery. Materials and Methods: Fifteen patients with benign parathyroid nodules were treated with MW ablation. Ultrasound, laboratory data, and clinical symptoms were evaluated before treatment; 1 week and 1, 3, 6, and 12 months after treatment; and every 6-12 months thereafter. Results: All patients were followed up for more than 1 year, with an average duration of 32.8 months +/- 17.9. Eleven patients underwent successful ablation in a single session, and two patients with bilateral disease and two patients with residual disease were treated with two sessions each. The rate of complete nodule disappearance was 17.6%. Nodule volume and serum parathyroid hormone (PTH) and calcium levels were significantly lower at the last follow-up than before treatment (volume, 0.39 cm(3) +/- 0.69 vs 2.62 cm(3) +/- 3:32; PTH, 54.5 pg/mL +/- 24.1 vs +/- 592.5 pg/mL +/- 579.1; and calcium, 2.32 mmol/L +/- 0.12 vs 2.93 mmol/L +/- 0.47; P < .01). Treatment was well tolerated. Minor complications included transient voice change in one patient. Conclusions: MW ablation is a safe and effective technique for the treatment of pHPT. It is a good alternative for patients who do not meet surgery criteria or decline surgery.