RFA May Have Role in Treating Secondary Hyperparathyroidism
Researchers caution that radiofrequency ablation should only be considered for patients ineligible for parathyroid surgery.
Ultrasound-guided radiofrequency ablation (RFA) of hyperplastic parathyroid glands may be a feasible option for treating selected patients with secondary hyperparathyroidism (SHPT) associated with chronic kidney disease, according to a new study.
Based on their findings, investigators concluded that, given the risk profile and limited effectiveness of the procedure, “it should only be considered as a possible alternative in patients who are not eligible for parathyroid surgery.”
The study involved 34 CKD patients with refractory SHPT who underwent ultrasound-guided radiofrequency ablation (RFA) of some or all parathyroid glands. Of these patients, 15 underwent RFA of all 4 glands, 10 had 3 glands ablated, and 9 had 1 or 2 glands ablated.
Following RFA, intact parathyroid hormone (iPTH), calcium, and phosphorus levels decreased in all groups. One year after RFA, these parameters remained significantly lower in the 4-gland ablation group compared with the 3-gland and 1- to 2-gland groups.
One year after RFA, 15 patients had iPTH levels in the reasonable range (less than 477 pg/mL) and 19 had excessive iPTH levels (477 pg/mL or higher). The researchers noted that, based on Kidney Disease: Improving Global Outcomes guidelines, PTH levels 2 to 9 times the upper limit of normal (106–477 pg/mL) is considered reasonable for patients with CKD stage 5.
Of the 15 patients with iPTH in the reasonable range, 12 (80%) had all 4 glands ablated whereas 3 had 1 to 3 glands ablated, Chengzhong Peng, MS, of Hangzhou Hospital of Traditional Chinese Medicine in Hangzhou, China, and colleagues reported online in Head & Neck. In addition, compared with the patients who had excessive PTH levels (477 pg/mL or higher) 1 year after RFA, the PTH levels on the first day after RFA were significant lower in the reasonable PTH group (138 vs. 903 pg/mL).
In addition, use of 272 pg/mL as a cutoff for PTH levels 1 day after ablation can predict PTH levels in the reasonable range 1 year after ablation with 89.5% sensitivity and 100% specificity.
“In order to achieve a good ablation effect, all hyperplastic parathyroid glands found on ultrasound should be ablated,” Peng's group wrote. “PTH levels 1 day after ablation might be a good indicator to assess the therapeutic effect.”
1. Peng C, Zhang Z, Liu J, et al. Efficacy and safety of ultrasound-guided radiofrequency ablation of hyperplastic parathyroid gland for secondary hyperparathyroidism associated with chronic kidney disease. Head Neck 2016; published online ahead of print.