Defining Success of Parathyroidectomy in Hyperparathyroidism
Objective To clearly define what constitutes successful parathyroidectomy in patients with primary hyperparathyroidism and to review our institution's results. Methods A retrospective chart review was conducted for consecutive patients who underwent parathyroidectomy at a university-affiliated tertiary care center between January 1998 and February 2006. Intraoperative pre- and post-excision PTH levels were recorded. PTH and calcium levels were recorded at 3 – 6 month intervals in the first 2 years and then yearly. Results 84 patients were analyzed. 50 (60%) had normal calcium and normal PTH levels following surgery, 28 (33%) had normal calcium and elevated PTH following surgery, and 6 (7%) had both elevated calcium and PTH. The mean follow-up time was 2.23 years, with a range of 0.25 to 5 years. Conclusions Surgery was successful, as indicated by normocalcemia, in 78 patients (93%). Of these 78 patients, 28 (33%) developed persistent PTH elevation without developing hypercalcemia. Other studies have studied this subgroup of patients with normalized post-operative calcium and consistently elevated PTH levels and noted that these new set points persist. Consequently, successful parathyroidectomy should be defined by serum calcium and not PTH levels.