Efficacy and safety of US-guided thermal ablation for primary hyperparathyroidism: a systematic review and meta-analysis

Purpose: To summarize the published literature on thermal ablation for primary hyperparathyroidism (PHPT) and to evaluate the effectiveness and safety of thermal ablation as a novel treatment strategy. Materials and methods: Two authors carried out the literature search using four databases independently, including PubMed, Embase, Cochrane, and Web of Science. The meta-analysis included prospective and retrospective data that compared post-ablative outcomes to pre-ablative values. The primary outcomes were parathyroid hormone (PTH), serum calcium and volume of the parathyroid gland (VPG). Results: From the 184 original articles, five studies (4 retrospective studies and 1 prospective study) examining 84 patients met the inclusion criteria. The meta-analysis showed significant reduction of PTH at 3 (standardized mean difference (SMD) = -1.09, 95% confidence index (CI) = -1.42 to -0.76, p < 0.001) and 6 months (SMD = -1.13, 95% CI = -1.46 to -0.80, p < 0.001) after thermal ablation. Serum calcium level was significantly reduced at 3 (mean difference (MD) = -0.31, 95% CI = -0.50 to -0.12, p = 0.001) and 6 months (MD = -0.31, 95% CI = -0.46 to -0.17, p < 0.001) after thermal ablation. There was no significant difference between pre-ablative VPG and that of 6 months after ablation (MD = -0.30, 95% CI = -0.70 to 0.09, p = 0.13). The most common complications were transient dysphonia and subcutaneous edema. No major complications or death occurred. Conclusion: Thermal ablation is effective and safe for treatment of PHPT. PTH and calcium levels were reduced significantly at 3 and 6 months after thermal ablation.