CD5 and B-cell chronic lymphocytic leukemia: CLL, a usually indolent disease, is unique in that CD5 positivity has been shown to be associated with superior outcomes to CD5- cases with a longer time to treatment (TTT) of 13.0 years in the CD5+ group compared to 5.8 years in the CD5- group and lower rates of lymphadenopathy (31.5% vs. 51.4%) and splenomegaly (16.1% vs. 42.1%) [26].