Letter to the editor - Hypoparathyroidism after parathyroidectomy in patients with multiple endocrine neoplasia type 1

Abstract

Multiple endocrine neoplasia type 1 (MEN1) is a genetic syndrome caused by inactivation of the MEN1 tumor suppressor gene, which confers increased susceptibility to the development of neoplasms, especially endocrine tumors such as parathyroid adenomas.¹ Although it is a rare disease, primary hyperparathyroidism resulting from hyperplasia and/or neoplasia of the parathyroid glands occurs in up to 97% of individuals with the syndrome.²

The treatment for hyperparathyroidism is surgical, and the two main techniques currently used are subtotal parathyroidectomy, involving the removal of 3.5 glands, and total parathyroidectomy with autotransplantation, in which all four glands are removed and a graft is prepared in the forearm.³ Although both approaches are employed, the choice of the optimal surgical technique for this condition remains under debate. A single study with a small cohort of 32 participants compared these two procedures and found no significant differences between them.⁴

The choice of surgical technique must consider the risk of recurrent hyperparathyroidism, given the multiglandular nature of the disease, and the risk of complications for example, hypoparathyroidism — defined by inappropriately low PTH levels in the presence of hypocalcemia.⁵ Traditionally, postoperative hypoparathyroidism is considered permanent when it persists for more than six months after surgery.⁶ However, this arbitrary definition is based on patients undergoing thyroidectomy and who do not have MEN1. Patients with MEN1 may have additional factors that delay the recovery of parathyroid function, such as previous malabsorptive surgeries, prolonged hungry bone syndrome, and removal of multiple glands. The latest international hypoparathyroidism guideline, published in 2022, proposed extending this limit to twelve months⁷, recognizing that functional recovery may be slower in specific contexts.