Previous studies using the antibody of clone EPR 17341 to detect secretory carcinoma and congenital fibrosarcoma harboring NTRK fusions showed a total of 23 cases with NTRK rearrangements detected on MSK-IMPACT were all identified by IHC, suggesting pan-TRK IHC showed the 100% accuracy (24). Here, NTRK1 is linked to congenital fibrosarcoma.