IGF1 and neoplasm: Tumor shrinkage ≥20% was observed in 54.1%, 56.3%, and 62.9% of patients at 12, 24, and 48 weeks, respectively, and mean GH ≤1.0 μg/L and IGF-1 normalization was reported in 21.4%, 23.4%, and 30.6% of patients at the same time intervals20.