Reoperative Surgery in Patients with Multiple Endocrine Neoplasia Type 1 Associated Primary Hyperparathyroidism

Persistent/recurrent primary hyperparathyroidism (pHPT) occurs frequently in multiple endocrine neoplasia type 1 (MEN1). We assessed the usefulness of intraoperative PTH (IOPTH) and preoperative localizing studies based on the outcome of patients with MEN1-associated pHPT undergoing reoperative surgery.

A retrospective analysis identified MEN1 patients with persistent/recurrent pHPT. Patient outcome was defined as postoperative serum calcium and PTH levels (cured, persistent or recurrent) at last follow-up. Positive predictive value (PPV) was calculated for imaging studies and IOPTH.

Thirty patients with MEN1-associated recurrent/persistent pHPT underwent 69 reoperative parathyroidectomies. Median follow-up time was 33 months. Persistent pHPT occurred in four (13 %) patients. IOPTH had a 92 % PPV for postoperative eucalcemia. Ultrasound and Tc99m-sestamibi had sensitivities of 100 and 85 % for localizing an enlarged parathyroid gland. However, five (17 %) patients had additional enlarged glands, not visualized preoperatively that were removed after IOPTH did not drop appropriately. Bone mineral density scores did not improve after reoperation (p = 0.60), but the rate of postoperative nephrocalcinosis did (p = 0.046). Patients with pancreatic neuroendocrine tumors had significantly higher rates of persistent/recurrent pHPT compared with those without (40 vs. 0 %, p = 0.021). Intraoperative and delayed parathyroid autotransplantation was performed in nine (30 %) and four (14 %) patients, respectively.

Although preoperative localizing studies are helpful for guiding reoperative strategy in MEN1 with persistent/recurrent pHPT, additional enlarged glands may be missed by conventional imaging. IOPTH should therefore be employed routinely in this setting. Routine cryopreservation should be considered in all patients. Pancreatic manifestation may be associated with earlier recurrence or persistent disease.