THE CLINICAL AND BIOLOGICAL FEATURES OF A SERIES OF IMMUNOPHENOTYPIC VARIANT OF B-CLL

We described the clinical and biological features of 63 cases of immunophenotypic variant of B-CLL (v-CLL) characterised by intermediate RMH score, in absence of t(11;14)(q13;q32) in FISH analysis in comparison with 130 cases of typical CLL. We observed significant differences in terms of age <70 yrs (p <.001), lymphocytosis <20 x 109/l (p <.001), lymphocyte doubling time <12 months (p = .02), high serum beta2-microglobulin levels (p <.001) and splenomegaly (p = .002); CD38, CD49d, CD1c were more expressed in v-CLL, CD43 in CLL (p <.001). IgVH mutation and trisomy 12 were more frequent in v-CLL group (p = .001; p<.001); del13q14 in CLL (p=.008). Gene expression profiling of nine v-CLL and 60 CLL indicated that the atypical group presented a specific molecular pattern. After a median follow-up of respectively 55 (4-196) and 60 months (6-180), 25/42 v-CLL (48%) and 55/93 CLL patients (59%) were treated. Time to treatment was significantly shorter in v-CLL when IgVH mutational status was considered (p= .006). The median overall survival was worse in v-CLL mutated cases (p= 0.062). In conclusion, v-CLL should be identified and dealt with separately from classic CLL. In particular, the prognostic markers that are routinely used to characterise classical B-CLL should not be interpreted as having the same meaning.