It is also noteworthy that tumours other than cartilaginous neoplasms can harbour the same IDH1/2 mutations assessed in our study, including carcinomas (predominantly cholangiocarcinoma), acute myeloid leukaemia and brain tumours although these mutations have never been identified in other primary bone tumours [12, 13, 31]. The gene discussed is IDH1; the disease is acute myeloid leukemia.