Similarly, subcutaneous insulin injection for the treatment of hyperglycemia in patients with type 2 diabetes mellitus may cause hyperinsulinemia, especially in the presence of insulin resistance, which, in turn, may stimulate the mitogenic pathways involving IR-A and IGF-1R leading to new cancer development or may accelerate cell proliferation in the existence of occult lung cancer cells (2). This evidence concerns the gene IGF1R and type 2 diabetes mellitus.