GH1 and neoplasm: Twelve studies described a tumor shrinkage effect according to the type of lesion (micro/macroadenoma), 37 provided information on the percentage of patients with “safe” GH levels: i.e., random GH levels below 2.0–2.5 μg/L in 23 studies [11]–[15], [20], [21], [25], [27], [36]–[42], [44], [46]–[51], random GH below 5 μg/L in 12 studies [17]–[19], [22], [23], [28], [29], [31]–[34], [43] and suppressed GH values during oral glucose tolerance test in two studies [30], [35].