Importantly, however, IgHV mutation status as a single variable was not prognostic for reduced PFS in this chemoimmunotherapy cohort—which is atypical in CLL—suggesting further large scale correlative studies are necessary to provide a comprehensive assessment of the associations between higher MTCP1 expression and other high-risk factors in CLL. Here, MTCP1 is linked to B-cell chronic lymphocytic leukemia.