Supplementary Material for: CIC-DUX4 rearranged sarcoma presenting in the skin: Case report.

Introduction: Capicua transcriptional repressor (CIC)-DUX4 rearranged sarcoma is a subtype of CIC-rearranged sarcomas composed of undifferentiated Wilms’ Tumor 1 (WT1)+, CD99+ round cells with recurrent CIC gene rearrangement. The diagnosis of CIC-rearranged sarcoma remains challenging, and the prognosis of CIC-rearranged sarcomas is poor. Case presentation: In this report, we described a case of CIC-DUX4 rearranged sarcoma presenting in the skin, expressing WT1 and CD99 in a dot-like pattern. In addition, the assessment of genomic alterations using genome panel testing was useful to confirm the accurate diagnosis. Conclusion: Our present case suggests that widespread use of genomic panel testing in the future may lead to early treatment and improve the prognosis of CIC-rearranged sarcomas.