Patients can be categorized in CD49d low (<30% positive CLL cells) and CD49d high (≥30%) cases based on the percentage of CD49d expression in CLL cells, with the CD49d high cohort having lower overall and treatment-free survival probability independent of the presence of other negative prognostic markers [117,118]. This evidence concerns the gene ITGA4 and B-cell chronic lymphocytic leukemia.