Sharain et al.31 found in a two-laboratory study that the overall sensitivity and specificity of TFE3 IHC for TFE3-rearranged neoplasms was 85% and 57% at Laboratory A, and 70% and 95% at Laboratory B, leading to Youden indices of 0.42 and 0.65, respectively (Youden index = sensitivity + specificity−1). Here, TFE3 is linked to neoplasm.