IGFBP2 and neoplasm: Moreover, plasma IGFBP-2 levels seem to be not associated with the extent of resection, since plasma IGFBP-2 levels were similar between patients underwent GTR and patients with residual tumor >30% (mean±SD, 646.4±57.0 ng/ml and 643.3±43.7 ng/ml respectively, Fig 2A).