B2M and B-cell chronic lymphocytic leukemia: To explore the correlation between TCF1 expression and the characteristics of patients with CLL, we next integrated a series of clinical characteristics, including disease state, Rai stage, β2 microglobulin (β2M) level, lactate dehydrogenase (LDH) level, gender, age, lymphocyte percentage, IGHV mutation status, cytogenetic abnormalities such as del(17p) or P53 mutation (TP53 aberration), del(11q), del(13q) and trisomy12, absolute lymphocyte count (ALC), and bulky disease (≥ 5 cm) (Figures 5A–N).