BTK and cyclic hematopoiesis: Particular attention was given to the interaction between CH and contemporary therapeutic strategies, including Bruton tyrosine kinase (BTK) inhibitors and BCL2 inhibitors, and their potential influence on long-term outcomes.<h4>Results</h4>Available evidence indicates that CH is relatively frequent in patients with CLL and may contribute to disease biology through mechanisms involving genomic instability, chronic inflammation and immune system alterations.