Hematopathology / LYMPHOMA WITH FOLLICULAR AND MONOCYTOID B-CELL COMPONENTS 516 Am J Clin Pathol 2000;114:516-522 © American Society of Clinical Pathologists Lymphomas With Follicular and Monocytoid B-Cell Components Evidence for a Common Clonal Origin

A b s t r a c t We investigated the clonal relationship between follicular center cell and monocytoid B-cell components of non-Hodgkin lymphoma by isolating the components and comparing the nucleotide sequences of the complementarity-determining region (CDR)3 of the rearranged immunoglobulin heavy chain (IgH) gene. Paraffin blocks from 4 cases with amplifiable DNA using the polymerase chain reaction (PCR) were identified. Multiple representative cell clusters of the 2 components were obtained by microdissection, and the IgH CDR3 was amplified using a seminested PCR. Most of the PCR products obtained from both tumor components in each case had identical lengths when analyzed with polyacrylamide gel electrophoresi