Ultrasonically guided chemical parathyroidectomy in patients with primary hyperparathyroidism: a follow‐up study

Abstract
We evaluated the long-term results in two different groups of patients with primary hyperparathyroidism treated with ultrasonically guided percutaneous ethanol (96%) injection into parathyroid tumours. A prospective long-term follow-up (more than 6 months). Ethanol (96%) was injected under ultrasonic guidance into biopsy verified solitary parathyroid tumours. Basic treatment included a maximum of three treatments with an interval of about 1 month (group 1) or 1 week (group 2). Dose of ethanol was half the volume of the parathyroid tumour. Two different groups of patients with only one ultrasonically detected and biopsy verified parathyroid tumour were treated. Group 1 (n = 18) were treated regardless of the severity of the hyperparathyroid disease. Group 2 (n = 14) were selected for treatment either due to severe hypercalcaemic symptoms (n = 3), a high surgical risk (n = 5), or refusal of surgery (n = 6). The volume of the parathyroid tumours was measured as half the product of maximum length, width, and depth. Blood tests included measurements of ionized calcium, total calcium and PTH. In group 1, 12 of 18 patients (66%) could be followed more than 6 months. Follow-up ranged from 12 to 58 months (median 45 months). A significant decrease (P < 0.001) in serum concentrations of ionized calcium and total calcium was observed. Eight patients (44%) later underwent surgical parathyroidectomy. Injection therapy was regarded as successful in 10 of 18 patients (56%). In group 2, 11 of 14 patients (79%) were followed more than 6 months. Follow-up ranged from 18 to 50 months (median 39 months). A significant decrease (P < 0.001) in serum concentrations of ionized calcium, total calcium and intact PTH (1-84) was observed. Treatment was successful in 11 of 14 patients (79%). Two patients required parathyroid surgery. Re-examination with ultrasound showed a significant reduction in the volume of the treated parathyroid tumours. Fibrosis surrounding the parathyroid tumours was detected in eight of 10 patients who subsequently had operations. One patient from each group had a complication of a unilateral permanent vocal cord paralysis following injection therapy. Partial or complete long-term remission of primary hyperparathyroidism can be achieved using ultrasound-guided chemical parathyroidectomy. However, the intervals between treatments should be short and the treatment should be reserved only for patients not fit for surgery.