Discordant results in the achievement of both GH levels ≤ 2·5 μg/l and normal IGF-I levels are frequently observed when treating acromegaly patients with somatostatin analogues,17,26 and also after surgery.27 Similarly, in our study there were 30 patients with GH levels ≤ 2·5 μg/l but high IGF-I levels, and two patients with normal IGF-I levels but high GH levels. Here, IGF1 is linked to acromegaly.