ISOLATED 13Q14 ABNORMALITIES AND NORMAL KARYOTYPES ARE ASSOCIATED WITH TYPICAL LYMPHOCYTE MORPHOLOGY IN B-CELL CHRONIC LYMPHOCYTIC-LEUKEMIA

Peripheral blood lymphocyte morphology and karyotype were correlated a cross the spectrum of cytogenetic abnormalities in 78 previously karyo typed cases of B-cell chronic lymphocytic leukemia (CLL). Cases were c lassified according to French-American-British morphologic criteria as typical CLL or CLL, mixed-cell type; the latter category was divided into CLL with a mixture of small and large cells and CLL with increase d prolymphocytes (CLL/PL). Other leukemic lymphoproliferative disorder s were excluded from this analysis. CLL cases with normal karyotypes w ere more likely to demonstrate typical morphology than those with clon al abnormalities (P=.042). In addition, all six cases containing isola ted 13q14 abnormalities had typical morphology, compared with six of 1 6 other isolated abnormalities (P=.009), including one of seven cases of isolated trisomy 12. In contrast with the cases of isolated 13q14 c hanges, only seven of 17 cases with 13q14 as part of complex abnormali ties had typical morphology (P=.012). Trisomy 12 was associated with m ixed-cell morphology, particularly CLL/PL, consistent with previous re ports. We conclude that isolated 13q14 abnormalities and normal karyot ype are associated with typical CLL morphology, while other clonal abn ormalities, including trisomy 12, are associated with mixed-cell morph ology. These results further support the concept of distinct CLL subgr oups based on karyotype. Furthermore, the association of trisomy 12 an d complex abnormalities with mixed-cell morphology may have implicatio ns for clonal evolution in CLL.