-MEN1 syndrome is composed of hyperparathyroidism, gastrinoma (pancreatic tumor) and pituitary tum or(remember the 3 Ps). Hyperparathyroidism in MEN1 is caused by hyperplasia of the parathyroid glands. Removal of 3 1/2 glands or total parathyroidectomy with autotransplantation is necessary.
