How to clinically interpret the results of TP53 analyses in chronic lymphocytic leukemia in the context of available therapeutic regimen

Abstract

TP53 gene mutations represent the most important adverse prognostic and predictive factor in patients with chronic lymphocytic leukemia (CLL) and contribute to an overall worse disease course and risk of early relapse or resistance to chemoimmunotherapy. Results to date suggest that first-line chemoimmunotherapy (FCR) results in clonal selection of TP53 aberrant cells, which has an adverse effect on disease prognosis. Recent studies investigating the clonal evolution of TP53 mutations under BCR and Bcl-2 inhibitor therapy do not suggest a similar trend. In the clinical diagnosis of TP53 aberrations, next-generation sequencing (NGS) methods are increasingly being used, achieving sensitivity of allelic frequency detection below 10% compared to standard Sanger sequencing. In recent years, the focus of CLL research has been on TP53 gene mutations with allelic frequencies below 10% and their clinical significance. In the following review article, we summarize the results published so far on the clonal evolution of TP53 gene mutations under different therapeutic regimens, especially with respect to mutations with an allelic frequency < 10% and their clinical interpretation.