FCER2 and mantle cell lymphoma: Regarding CD22, CD79b, FMC7, and CD23 expressions in the Matutes score, CD23 expression was negative in 11 (3.5%) CLL patients (3 had typical CLL and 8 had atypical CLL), whereas it was positive in 6 (21.2%) MCL patients CD23 expression was not diagnostic for CLL but it was significantly more expressed in CLL patients (p<0.001).