Dipartimento di Scienze Biomediche - Sezione di Ematologia
Università di Ferrara - Via Savonarola, 9 - 44100 FERRARA - ITALY
tel. int+39.0532.236978; fax: int+39.0532.212142; e-mail email@example.com
A classification of chronic (mature) B-cell lymphoproliferative disorders based on reproducible morphologic and immunologic criteria was proposed by the FAB group in 1989. Ever since a number of cytogenetic studies disclosed a remarkable degree of heterogeneity within each disease category. In this table the main cytogenetic entities of chronic lymphocytic leukemia and related disorders, B-cell prolymphocytic leukemia, splenic lymphoma with villous lymphocytes are presented.
Other disease subsets of B-cell CLD include the leukemic phase of follicle
centre cell lymphoma, mantle cell lymphoma and lymphoplasmacytic lymphoma. The
cytogenetic features of these forms of leukemic lymphoma are the described in
the table dealing with NHL.
Putative cell of origin and immunophenotype
Corresponding cytologic and clinical features
CD5+ B cell that has encountered the antigen and harbours hypermutated IgV genes
CD5+; CD23+; CD38+/-; CD22 weak+; FMC7-; sIg+ weak
CD5+ virgin recirculating B-cell with germline IgV genes
CD5+; CD23+; CD38-/+; CD22 weak+; FMC7-; sIg+ weak3
+12 (10-15% of the cases
CD5+ recirculating B-cell
CD5+; CD23+; CD22 weak+; FMC7-; sIg+ weak3
Prolymphocytic leukemia (PLL)
Peripheral B-lymphocyte that has encountered the antigen and harbours hypermutated IgV genes
t(11;14)(q13;q32) (BCL1 involved in the MTC and mTC1)
Rare and aggressive disease with a majority of relatively large lymphocytes with round nucleus and a prominent central nucleolus
Splenic lymphoma with villous lymphocytes
Legend : +: positive in >90% of the cases; +/-: positive in more than 50% of the cases; -/+: positive in less than 50% of cases; -: positive in <10% of the cases; pan-B markers include CD19; CD20; CD79a R = rearranged; sIg: surface immunoglobulins; cyIg: cytoplasmic Ig; IgV genes: genes encoding for the variable portion of the Ig. MTC and mTC1: major translocation cluster and minor translocation cluster 1 of BCL1 region, respectively.