Acromegaly is usually the result of a pituitary growth hormone cell-adenoma or is more rarely due to ectopic secretion of growth hormone releasing hormone (GHRH).We report the case of a 60-year-old woman with acromegaly due to a GH-RH-secreting pancreatic tumor. Laboratory evaluation confirmed the diagnosis of acromegaly. Magnetic resonance imaging revealed a partial empty sella with no signs of adenoma. Ultrasound sonography performed for abdominal pains showed a calcified large heterogeneous infrahepatic mass. Computed tomography scan discovered a heterogeneous pancreatic head mass with a diameter of 10cm. Measurement of fasting plasma GHRH was performed showing a high concentration of 604ng/L (normal 10-60). We therefore concluded that the acromegaly was caused by ectopic overproduction of GHRH likely due to the pancreatic tumor. The patient underwent a cephalic duodenopancreatectomy. Histology revealed a well-circumscribed tumor with organoid architecture. Immunohistochemistry demonstrated diffuse positivity for chromogranin A, neuronal specific enolase and synaptophysin and negative immunoreactivity for prolactin, GH and serotonin. These features were concordant with a well-differentiated neuroendocrine tumor of the pancreas. Surgical resection of this pancreatic tumor was followed by significant amelioration of acromegalic signs and normalization of GHRH and GH levels.
Published by Elsevier Masson SAS.