Do tumors ever cause acromegaly or gigantism by making excessive GHRH?
- Yes. Rare cases of GHRH production by various tumors have been described in the lung, gastrointestinal tract, or adrenal glands. They cause acromegaly by stimulating pituitary secretion of GH.
- The clinical and biochemical features of acromegaly are indistinguishable from those of acromegaly caused by a pituitary adenoma.
- Pituitary enlargement also occurs as a result of hyperplasia of somatotrophs. Some patients have had inadvertent transsphenoidal surgery (TSS) before the correct diagnosis was made.
- Therefore the plasma level of GHRH should be measured in any patient with acromegaly as well as an extrapituitary abnormality or hyperplasia on pituitary pathology.