When initial postexcision PTH level does not fall appropriately during parathyroidectomy: what to do next?

Area of Science:

• Endocrinology
• Surgical Oncology
• Neurosurgery

Background:

• Inadequate intraoperative parathyroid hormone (PTH) level decrease after parathyroid gland excision can indicate persistent hyperfunction or a false negative result.
• Management strategies for patients with inadequate PTH fall require careful consideration to avoid unnecessary interventions.

Purpose of the Study:

• To analyze the intraoperative management of patients with primary hyperparathyroidism experiencing an inadequate fall in PTH levels after enlarged parathyroid gland excision.
• To determine the incidence and implications of false-negative PTH assays in this context.

Main Methods:

• Prospective analysis of 193 procedures for primary hyperparathyroidism in 189 patients.
• Intraoperative PTH levels measured before and 10-15 minutes after enlarged parathyroid gland excision.
• Successful parathyroidectomy defined by a >50% PTH decrease into the normal range.

Main Results:

• 48 of 193 operations (25%) showed an inadequate postexcision PTH fall.
• A false-negative PTH result occurred in 16 patients (33% of inadequate falls), with cure achieved without further dissection in most.
• Preoperative imaging findings correlated with operative findings in all false-negative cases.

Conclusions:

• An inadequate intraoperative PTH fall can be a false negative, especially after adenoma removal guided by preoperative imaging.
• Repeat PTH measurement can confirm a false negative, potentially obviating additional neck dissection.
• If repeat PTH levels remain inadequate, further neck exploration is warranted.