IGFBP2 and lung cancer: We found serum anti-IGFBP-2 antibody level of lung cancer patients (mean, 1633.318 ng/ml; median, 1651.462 ng/ml; range, 342.732–4932.582 ng/ml) was significantly higher than that of patients with benign lung disease (mean, 1210.139 ng/ml; median, 1035.900 ng/ml; range, 547.596–2331.167 ng/ml) and normal controls (mean, 1303.369 ng/ml; median, 1194.800 ng/ml; range, 528.200–2140.500 ng/ml) (P<0.001, Fig. 1A).