SAN DIEGO – Intraoperative spikes of parathyroid hormone don’t predict a failed parathyroidectomy, according to a retrospective study of patients who had the surgery for hyperparathyroidism.
They should, however, raise the suspicion of multigland disease, Richard Teo said at the Association for Academic Surgery/Society of University Surgeons Academic Surgical Congress.
“Significantly more patients with intraoperative spikes didn’t achieve this drop, and they had a higher rate of multigland disease requiring bilateral neck exploration,” he said. “But although spikes did increase the suspicion of multigland disease, they did not affect the operative success rate in this study.”
He presented a retrospective analysis of 683 patients who underwent parathyroidectomy for hyperparathyroidism. These patients were largely female (76%). Those who had the intraoperative spikes were older (60 vs. 58 years) and had higher preoperative calcium than patients without spikes. There were no differences in parathyroid hormone (PTH) or creatinine levels.
Operative success – described as normocalcemia at least 6 months after surgery – occurred in 98% of the entire group. The operative failure rate was 0.9%, and the recurrence rate was 1%. About 5% of the entire group had multigland disease.
Intraoperative PTH spikes occurred in 224 patients (33%). Compared with those without spikes, patients with spikes were significantly less likely to achieve the PTH decrease of 50% or greater at 10 minutes after gland excision (70% vs. 90%).
Bilateral neck explorations were significantly more common among those with spikes (10% vs. 5%), as was multigland disease (8% vs. 3%). There was no significant difference in operative time (54 vs. 59 minutes).
Postoperative outcomes were similar. At last follow-up, calcium levels were identical (9.3 mg/dL) in the group with and the group without a spike in PTH. In addition, the PTH levels were not significantly different (47 vs. 57 pg/mL).
Operative success was achieved in 98% of both groups, with a 2% failure rate in both groups. Recurrence was slightly, though not significantly, less in the spike group (0.4% vs. 1.3%).
“We were able to show that intraoperative PTH spikes don’t predict a poor outcome of parathyroidectomy,” Mr. Teo said. “We also feel this study reaffirms the clinical utility of the 50% or greater intraoperative PTH drop as a predictor of the successful removal of all hypersecreting parathyroid tissue during parathyroidectomy guided by intraoperative PTH monitoring.”
He had no financial disclosures.