To confirm the expression levels of TGFB1 and FN1 in chordoma and their correlation with recurrence, we performed IHC on clinical samples including 10 primary chordomas and 10 recurrent chordomas, which revealed significantly higher expression levels of TGFB1 and FN1 in recurrent chordoma than in primary tumours (Figure 5I,J), indicating a potential association between EMT and chordoma recurrence. Here, FN1 is linked to chordoma.