Fig. 6: TRIM63 overexpression was highly specific to MiTF-RCC among all major and rare RCC subtypes and TRIM63 RNA-ISH results were highly concordant to the TFE3/TFEB FISH results.

A Bar plot of TRIM63 expression in diverse RCC subtypes represented by H-score. The majority of MiTF-RCC cases overexpressed TRIM63 as reflected by high H-score. The other RCC subtypes exhibited low to none TRIM63 expression in most cases. B The area under the receiver-operating-characteristic (ROC) curve (AUC) showing the diagnostic values of TRIM63 expression in MiTF-RCC. An H-score cutoff value of 168 (rounded off from 167.5) yielded 100% specificity and 90% sensitivity with superior diagnostic performance (AUC:98.5%). C Comparison between TRIM63 RNA-ISH and TFE3/TFEB FISH results by Bar plot and Venn diagram showed high concordance between the two assays. Overall, 41/44 (93.2%) FISH-positive cases were TRIM63 positive; 41/49 (83.7%) FISH-negative cases were TRIM63 negative. The Bar plot included all 31 cytogenetically confirmed MiTF-RCC cases and 70 cases clinically and morphologically suspected to be MiTF-RCC with confirmatory FISH data. In the Venn diagram, purple area (in the middle) represents TRIM63 RNA-ISH and TFE3/TFEB FISH double-positive cases, light purple (on the right) area represented TFE3/TFEB FISH positive, TRIM63 RNA-ISH negative cases, and brown area (on the left) represents TRIM63 RNA-ISH positive, TFE3/TFEB FISH-negative cases. D Comparison between TRIM63 RNA-ISH and TFE3/TFEB FISH by Box plot and Wilcoxon test showed a significant difference in TRIM63 RNA-ISH H-scores between TFE3/TFEB FISH positive and negative cases.