Areas of uncertainty regarding the risks associated with hGH pertain to management (when to initiate hGH and safe doses of hGH) and to difficulties in the assessment of added risks for adverse tumor outcomes conferred by hGH in children who require maintenance chemotherapy, in those with cancer predisposing syndromes and, overall, in adult survivors of childhood cancer and brain tumors. Here, GH1 is linked to childhood malignant neoplasm.