On the other hand, Viacava et al. [20] found no differences in VEGF expression among tumors of different histotypes, and McCabe et al. comparing VEGF in a series of adenomas composed of 77% nonfunctioning adenomas and only 4% of prolactinomas found the highest expression in nonfunctioning adenomas and GH producing adenomas [22]. Here, GH1 is linked to adenoma.