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Paper text:
new targeted inhibitors of bcell receptor , such as ibrutinib , yield remarkable responses in patients with cll .
an 83yearold man with cll refractory to rituximab and bendamustine presented a massive enlargement of mesenteric lymph nodes without histologic transformation into richter syndrome .
a transient lymphocytosis up to 85  10/l after 1 month of therapy was considered to be treatment related 1 . on the other hand
, sequential ct scanning demonstrated a progressive shrinkage of the abdominal lymph nodes with the best overall response obtained at 12 months ( fig .
the concomitant minimal residual disease ( mrd ) negativity in the blood or bone marrow denoted complete response ( international workshop on cll criteria ) 2 .
progressive changes in abdominal lymph nodes by ct scan in a patient with cll treated with ibrutinib .
images refer to baseline ( panel a ) and to evaluation after 3 ( panel b ) , 6 ( panel c ) , 12 ( panel d ) , and 24 ( panel e ) months of therapy .
key clinical messageunlike chemoimmunotherapy regimens , which are given for a defined period , ibrutinib , a firstinclass bruton 's kinase inhibitor , allows most patients with cll to remain on treatment for an extended period . 
 our experience , supported by sequential ct scan images , suggests that longterm ibrutinib promotes a high response rate that improves in quality with time .