TRIM63 and alveolar soft part sarcoma: In this study, we sought to quantitatively evaluate TRIM63 RNA-ISH in a cohort of ASPS cases, and select other tumors with similar morphology, to assess the performance of TRIM63 RNA-ISH for ASPS and to highlight diagnostic scenarios in which TRIM63 RNA-ISH may have utility and clinical value for distinguishing and/or confirming a diagnosis of ASPS.