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. The gene discussed is BCL2; the disease is cyclic hematopoiesis.