Growth hormone isoforms in acromegalic patients before and after treatment with octreotide LAR

Our study confirmed that acromegalic patients have an increased proportion of circulating 20 kDa-hGH isoform. Consequently, the use of a 22 kDa-hGH specific assay may underestimate the tumor production of total GH. Although octreotide LAR promoted a significant decrease in the GH and IGF-I levels, it did not normalize the GH isoforms composition and suggests that the secretion of GH isoforms is equally inhibited by somatostatin analogues and that it is the disease control that normalizes the GH isoforms composition in acromegaly.