Parathyroidectomy for Tertiary Hyperparathyroidism: A Multi-Institutional Analysis of Outcomes

Background: Patients with tertiary hyperparathyroidism (HPT) often experience delays between diagnosis and referral for surgical treatment. We hypothesized that patients with tertiary HPT experience similarly high cure rates and low complication rates after parathyroidectomy compared with patients with primary HPT. Methods: We retrospectively identified patients undergoing parathyroidectomy from the Collaborative Endocrine Surgery Quality Improvement Program for primary or tertiary HPT from January 2014 to April 2019. Patients were categorized according to their primary diagnosis and compared for cure rates and surgical complications. Results: The study included 9030 patients, with 334 (3.7%) being treated for tertiary HPT. Parathyroidectomy provided a high cure rate (93.7%) in patients with tertiary HPT. However, adjusting for age, sex, and prior thyroid or parathyroid surgery, tertiary HPT was associated with a greater chance of persistent disease than was primary HPT (odds ratio: 2.3, 95% confidence interval: 1.3-4.0). Overall, complications were low for patients across both groups. However, patients with tertiary HPT were more likely to present to the emergency department (7.5% versus 3.3%; P < 0.001), be readmitted (5.1% versus 1.1%; P < 0.001), and develop a hematoma (1.5% versus 0.2%; P = 0.002). Both groups of patients shared similarly low rates of other complications, including mortality, vocal cord dysfunction, and surgical site infections (P < 0.5% for all). Conclusions: Patients undergoing parathyroidectomy for tertiary HPT experience high cure rates and low complication rates. However, tertiary HPT is associated with a greater chance of persistent disease and select complications. Nevertheless, the low rates of persistent disease and complications should not deter early referral for the treatment of tertiary HPT.