Intraoperative Parathormone Measurement in Patients with Multiple Endocrine Neoplasia Type I Syndrome and Hyperparathyroidism

Abstract

Total or subtotal parathyroidectomy is considered the treatment of choice for multiple endocrine neoplasia type I (MEN-I)-associated primary hyperparathyroidism (HPT). However, persistent or recurrent HPT is frequently observed. The development of a rapid two-site immunoradiometric assay (IRMA) method for measuring intact parathormone (PTH) has provided a valuable tool for recognizing possible surgical failures. Our experience includes 16 MEN-I patients (10 females, 6 males) of mean age 35.5 years operated on between 1990 and 1996. Total parathyroidectomy (TPTX) with autotransplantation of parathyroid tissue was the standard treatment. Blood samples for PTH measurement were drawn at the induction of anesthesia (basal value), 10 and 20 minutes after the removal of each gland, and 60 minutes after TPTX. Rapid PTH measurement, which required only 15 minutes of incubation at 37 degrees C, showed a highly significant correlation (p < 0.0001) with the standard method. Circulating PTH levels exhibited a stepwise decrease during TPTX, reaching a mean value of 22.3% of the baseline 20 minutes after removal of the last gland. Two patients showed a prompt decrease of PTH after removal of the single enlarged gland, featuring the kinetics observed in the adenomas. One of these two patients was successfully treated with more conservative surgery. None of the patients showed persistence or recurrence of HPT. In our experience, intraoperative measurement of PTH seems to be a valuable adjunct in both the diagnosis of multiglandular involvement and the prediction of surgical treatment in patients with primary parathyroid hyperplasia.

Persistent and Recurrent Hyperparathyroidism After Total Parathyroidectomy With Autotransplantation

“…Accurate measurements of iPTH levels after predilution to 10ϫ and 100ϫ made the data more dependable and the localization more correct. We did not use intraoperative parathyroid hormone measurements, 14 but this might be very useful for the complete removal of parathyroid tissue, whether in primary surgery or in persistent and recurrent disease.…”

CONSENSUS: Guidelines for Diagnosis and Therapy of MEN Type 1 and Type 2

“…The much higher likelihood of postoperative hypoparathyroidism from this strategy should first be discussed with the patient. Intraoperative measurement of PTH on-line during any initial or repeat surgery is a promising method to test whether parathyroid tumor remains (21).…”

Surgical Approach in Hereditary Hyperparathyroidism

“…its sensitivity in the surgical treatment of sporadic adenoma is nearly 95% [5,17,18]. When used for the discrimination of hPT due to hyperplasia or multiglandular disease, quick intraoperative PTh has shown a substantial-least 3-3 1/2 glands; and 3) total parathyroidectomy with transcervical thymectomy (TPTX) and autologous graft of parathyroid tissue.…”

“…fifth, quick intraoperative PTh measurement has become an important diagnostic tool in clinical practice to guide hPT surgery [16,17]. its sensitivity in the surgical treatment of sporadic adenoma is nearly 95% [5,17,18].…”