While parathyroid hyperplasia or adenoma is commonly found in patients who also have gastrin-producing tumors (Zollinger-Ellison syndrome), to our knowledge the influence of one on the other has not been previously documented.
Four patients with elevated serum gastrin levels had elevated serum calcium levels. All underwent parathyroidectomy. Three patients had a marked clinical improvement and decreased basal acid secretion after calcium levels were returned to normal. Two patients demonstrated a prompt decline in serum gastrin levels following excision of parathyroid adenomas or hyperplastic glands. The fourth patient had a previous total gastrectomy and persistently elevated serum gastrin levels. He developed hypercalcemia years later.
Turbey WJ, Passaro E. Hyperparathyroidism in the Zollinger-Ellison SyndromeInfluence of Hypercalcemia on Clinical Course. Arch Surg. 1972;105(1):62-66. doi:10.1001/archsurg.1972.04180070060012