IGLV3-21 R110 Is a Prognostic Marker for Early Stage CLL Patients Under Ibrutinib Treatment or Watch & Wait: Results from the Double-Blind, Randomized, Placebo-Controlled GCLLSG CLL12 Trial

INTRODUCTION: IGLV3-21 R110 is a point mutation that can confer the ability for autonomous signaling to B cell receptors (BCR) using light chains encoded by the allele IGLV3-21 ∗ 01 or IGLV3-21 ∗ 04. Chronic lymphocytic leukemia (CLL) patients with IGLV3-21 R110 have a shorter time to first treatment and shorter overall survival, independent of their IGHV mutational status. However, outcomes of CLL patients using IGLV3-21 R110 have not been evaluated in clinical trials of BTK inhibitors.