A >50% Intraoperative Parathyroid Hormone Decrease Into Normal Reference Range Predicts Complete Excision of Malignancy in Patients With Parathyroid Carcinoma

Valerie L Armstrong; Tanaz M Vaghaiwalla; Cima Saghira; Cheng-Bang Chen; Yujie Wang; Johan Anantharaj; Mehmet Ackin; John I Lew

doi:10.1016/j.jss.2023.11.074

A >50% Intraoperative Parathyroid Hormone Decrease Into Normal Reference Range Predicts Complete Excision of Malignancy in Patients With Parathyroid Carcinoma

J Surg Res. 2023 Dec 27:S0022-4804(23)00646-7. doi: 10.1016/j.jss.2023.11.074. Online ahead of print.

Authors

Valerie L Armstrong¹, Tanaz M Vaghaiwalla², Cima Saghira³, Cheng-Bang Chen³, Yujie Wang³, Johan Anantharaj², Mehmet Ackin³, John I Lew⁴

Affiliations

¹ Department of General Surgery, Mayo Clinic Arizona, Phoenix, Arizona. Electronic address: Armstrong.valerie@mayo.edu.
² Section of Endocrine Surgery, Department of Surgery, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee.
³ DeWitt Daughtry Department of Surgery, University of Miami Miller School of Medicine, Miami, Florida.
⁴ DeWitt Daughtry Department of Surgery, University of Miami Miller School of Medicine, Miami, Florida; Division of Endocrine Surgery, DeWitt Daughtry Department of Surgery, University of Miami Miller School of Medicine, Miami, Florida.

PMID: 38155027
DOI: 10.1016/j.jss.2023.11.074

Abstract

Introduction: The mainstay of successful treatment for parathyroid carcinoma remains complete surgical excision. Although intraoperative parathyroid hormone (ioPTH) monitoring is a useful adjunct during parathyroidectomy for benign primary hyperparathyroidism, its utility for parathyroid carcinoma remains unclear.

Methods: A retrospective review of 796 patients who underwent parathyroidectomy with ioPTH monitoring for primary hyperparathyroidism revealed 13 patients with parathyroid carcinoma on final pathology from two academic institutions. A systematic review yielded 5 additional parathyroid carcinoma patients. Complete excision of malignancy, or operative success (eucalcemia ≥6 mo. after parathyroidectomy); operative failure (persistent hypercalcemia <6 mo. after parathyroidectomy); and perioperative complications were evaluated. Comparison of the >50% ioPTH decrease alone to >50% ioPTH decrease into normal reference range was analyzed using Chi-squared, Kolmogorov-Smirnov, Kruskal-Wallis tests.

Results: All 18 parathyroid carcinoma patients achieved a >50% ioPTH decrease, and 14 patients also had a final ioPTH level decrease into normal reference range. 93% of patients who met normal parathyroid hormone reference range had operative success, whereas only two of the four (50%) patients with parathyroid carcinoma with a >50% ioPTH decrease alone demonstrated operative success.

Conclusions: Parathyroidectomy guided by a >50% ioPTH decrease into normal reference range may better predict complete excision of malignant tissue in patients with parathyroid carcinoma compared to >50% ioPTH decrease alone. IoPTH monitoring should be used in conjunction with clinical judgment and complete en bloc resection for optimal treatment and success.

Keywords: Intraoperative PTH monitoring; Parathyroid cancer; Parathyroid carcinoma; Parathyroid malignancy; Primary hyperparathyroidism; ioPTH monitoring.