Two Different Pituitary Adenomasin a Patient with Multiple Endocrine Neoplasia Type 1 Associated with Growth Hormone-Releasing Hormone-Producing Pancreatic Tumor: Clinical and Genetic Features

Abstract

The clinical and genetic features of a 43-year-old male patient with multiple endocrine neoplasia type 1 were reported. He developed hyperparathyroidism, a GHRH-producing pancreatic tumor, and acromegaly between 1980 and 1983. Because his pituitary gland increasedin size even after resecting the GHRH-producing pancreatic tumor, transsphenoidal hypophysectomy was performed six years later. The pituitary contained two histologically-different adenomas composed of somatotroph cells and null cells. Genetic analyses revealed loss of heterozygosity on chromosome 11in commonin the pituitary adenomas, the pancreatic endocrine tumors, and a parathyroid hyperplasia. on the other hand, mutations of ras, p53, Gsα, and Gi2α genes were not foundin these tumors. The loss of the tumor suppressor gene on chromosome 11q12-13 was involvedin the formation of two pituitary adenomas, two pancreatic endocrine functioning tumors, and a parathyroid hyperplasiain this patient, but the tumorigenic factorsin the specific endocrine organs remain to be studied. © 1995, The Japan Endocrine Society. All rights reserved.