Endocrine Abstracts

Aim: Focussed parathyroidectomy is an established technique in subjects where imaging has identified a single parathyroid lesion. The aim of this study was to examine the long-term cure rate following this procedure.

Method: Of 188 patients undergoing surgery for primary hyperparathyroidism between 2001 and 2006, 150 had a single parathyroid lesion on imaging using sestamibi +/− neck ultrasound. These patients were treated by focused parathyroidectomy (FP) and the remainder (n=38) underwent bilateral neck exploration (BNE). Patients having FP were discharged with 2 weeks of calcium and vitamin D replacement.

Results: There was no difference in calcium levels between the 2 groups (Mean±S.E.M.) (FP: 2.77±0.28; BNE 2.76±0.02 mmol/l). 5 patients had a PTH >400 ng/l (range 404–735), 1 with parathyroid carcinoma, and 4 with severe vitamin D deficiency (<10 ug/l). No patients were admitted with post-operative hypocalcaemia.

Of the 150 patients undergoing FP, 148 patients were cured by initial surgery (99%) and remain normocalcaemic at 3 months. One patient had a second adenoma removed during a second operation one year later, and the other was found to have MEN-1, requiring total parathyroidectomy. Long-term data (1–5 years after parathyroidectomy) is available in 76 of patients and all (100%) remain cured - calcium 2.31±0.01 mmol/l. In the BNE group 37 (97%) were cured by initial surgery and, in 18 patients where long-term follow-up data is available, all remain cured (Calcium 2.28±0.02 mmol/l). The patient not cured by BNE had a fifth, ectopic mediastinal gland excised during a second operation.

In the FP group, histology demonstrated a parathyroid adenoma in 145 cases and 2 cases of parathyroid carcinoma. 3 cases reported as possible hyperplasia or adenoma have all remained normocalcaemic. Three patients with a parathyroid adenoma also had pituitary tumours, but all were MEN-1 gene mutation negative.

Conclusion: Focussed parathyroidectomy is associated with an excellent long-term cure. Following up patients for an appropriate period of time is important as histological diagnosis can be difficult on a single parathyroid gland.