A rare case of an elderly male with progression to chronic myeloid leukaemia secondary to chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is a lymphoproliferative disorder characterised by an accumulation of monoclonal B lymphocytes, with an increased risk of secondary cancers. The coexistence of CLL and chronic myeloid leukaemia (CML) is a rare phenomenon, with three main types being classified: CML preceding CLL, CLL preceding CML and simultaneous occurrence. The coexistence of these chronic leukaemias poses a complex clinical challenge, with the underlying mechanisms of their association remaining enigmatic. Here, we present a report of an elderly male with a long history of CLL, who was subsequently diagnosed with secondary CML.