Prospective study of surgery for primary hyperparathyroidism (HPT) in multiple endocrine neoplasia-type 1 and zollinger-ellison syndrome long-term outcome of a more virulent form of HPT

Background: Primary hyperparathyroidism (HPT) in multiple endocrine neoplasia type 1 (MEN1) patients with Zollinger-Ellison syndrome (ZES) is caused by parathyroid hyperplasia. Surgery for parathyroid hyperplasia is tricky and difficult. Long-term outcome in ZES/MEN1/HPT is not well known. Methods: Eighty-four consecutive patients (49 F/35 M) with ZES/ MEN1/HPT underwent initial parathyroidectomy (PTX) and were followed at 1- to 3-year intervals. Results: Age at PTX was 36 < 2 years. Mean follow-up was 17 < 1 years. Before PTX, mean Ca = 2.8 mmol/L (normal level (nl >2.5), PTH i = 243 pg/mL (nl >65), and gastrin = 6950 pg/mL (nl > 100). Sixty-one percent had nephrolithiasis. Each patient had parathyroid hyperplasia. Fifty-eight percent of patients had 4 parathyroid glands identified. Nine of 84 (11%) had 4 glands removed with immediate autograft, 40/84 (47%) 3 to 3.5 glands, whereas 35/84 (42%) >3 glands removed. Persistent/recurrent HPT occurred in 42%/48% of patients with >3 glands, 12%/44% with 3 to 3.5 glands, and 0%/55% with 4 glands removed. Hypoparathyroidism occurred in 3%, 10%, and 22%, respectively. The disease-free interval after surgery was significantly longer if ]3 glands were removed. After surgery to correct the HPT, each biochemical parameter of ZES was improved and 20% of patients no longer had laboratory evidence of ZES. Conclusions: HPT/MEN1/ZES is a severe form of parathyroid hyperplasia with a high rate of nephrolithiasis, persistent and recurrent HPT. Surgery to correct the hypercalcemia significantly ameliorates the ZES. Removal of less than 3.5 glands has an unacceptably high incidence of persistent HPT (42%), whereas 4-gland resection and transplant has a high rate of permanent hypoparathyroidism (22%). More than 3-gland resection has a longer diseasefree interval. The surgical procedure of choice for patients with HPT/MEN1/ZES is 3.5-gland parathyroidectomy. Careful long-term follow-up is necessary as a significant proportion will develop recurrent HPT.