Torimoto K, et al. - For detecting insulinoma, researchers determined the optimal cutoff values of hemoglobin A1c (HbA1c) and glycated albumin (GA). This multicenter cross-sectional study included 31 patients with insulinoma, with 120 controls with normal glucose tolerance matched by traits to the patients. For the diagnosis of insulinoma, the optimal cutoff values of HbA1c and GA were 5.0 and 12.4%, respectively, in a receiver operating characteristic analysis. Significantly lower HbA1c and GA values were detected in patients with insulinoma vs healthy controls. For the first time ever, effective cutoff values for screening in the diagnosis of insulinoma were determined. Based on the findings, HbA1c and GA could have utility as indices for insulinoma screening, as well as for malignant insulinoma, as malignant insulinoma has a similar diagnostic process to that of benign insulinoma.