TP53 and B-cell chronic lymphocytic leukemia: CLL patients with TP53 dysfunction have seen much improved but not definitive disease control with small molecule agents such as venetoclax (BCL-2 inhibitor) and ibrutinib (Bruton tyrosine kinase inhibitor), especially when used in combination with rituximab and obinutuzumab or idelalisib (Farooqui et al., 2015; Roberts et al., 2016; Stilgenbauer et al., 2016; Hallek 2019).