Non‐lymphoid blast crisis of CML with rearrangement of immunoglobulin and T‐cell receptor delta genes

Abstract

We report a patient with chronic myeloid leukaemia (Philadelphia-positive with M-BCR rearrangement) in transformation whose blast cells had myelomonocytic morphology, absent terminal deoxynucleotidyl transferase expression and non-lymphoid cell surface markers (CD10-, CD19-, CD33+, CD14+, CD11+). Leukaemia cell DNA showed rearrangement of both immunoglobulin heavy chain and T-cell receptor delta genes. Such rearrangements may be a feature of a small proportion of patients with non-lymphoid transformation of CML as they are in a minority of cases of de novo acute non-lymphoblastic leukaemia.