Numerical cytogenetic abnormalities of chromosomes 3, 7, and 12 in marginal zone B-cell lymphomas.
Monocytoid B-cell lymphoma, low-grade B-cell lymphoma of mucosa-associated lymphoid tissue, and primary splenic marginal zone cell lymphoma (SMZCL) were originally described as distinct clinicopathologic entities. On the basis of morphologic and immunologic similarities, monocytoid B-cell lymphoma and lymphoma of mucosa-associated lymphoid tissue recently have been grouped together as nodal and extranodal types of marginal zone B-cell lymphomas (MZBCLs) in the Revised European-American Classification of Lymphoid Neoplasms. Primary SMZCL, although related, is considered a separate provisional entity. Trisomies 3, 7, and 12 are common in non-Hodgkin's lymphomas. Several recent studies reported that MZBCLs arising in sites of mucosa-associated lymphoid tissue have a high frequency of trisomy 3. To assess whether similar numerical cytogenetic abnormalities are present in MZBCLs with prominent monocytoid B-cell cytologic features, we performed a retrospective study, using formalin-fixed, paraffin-embedded tissue blocks from 36 cases. By use of fluorescence in situ hybridization to detect chromosome trisomies, we identified trisomy 3 in 11 (85%) of 13 extranodal MZBCLs with monocytoid B cells (MZBCL-Es), in 6 (50%) of 12 nodal MZBCLs of monocytoid B-cell type (MZBCL-Ns), but in only 2 (18%) of 11 SMZCLs. Trisomies 7 and 12 were found at lower frequencies. These data suggest that trisomy 3 is a common numerical chromosomal abnormality of MZBCL-Es and MZBCL-Ns with monocytoid B-cell features. Despite similar morphologic and immunophenotypic characteristics, the low incidence of trisomy 3 in the SMZCL cases implies that this process may be genetically distinct.
Division of Pathology, City of Hope National Medical Center, Duarte, CA 91010, USA. rbrynes@smtplink.coh.org
R K
RK
Brynes
P D
PD
Almaguer
K E
KE
Leathery
A
A
McCourty
D A
DA
Arber
L J
LJ
Medeiros
B N
BN
Nathwani
D002460:Cell Line; D002869:Chromosome Aberrations / Q000175:diagnosis* / Q000235:genetics; D025063:Chromosome Disorders; D002881:Chromosomes, Human, Pair 12; D002893:Chromosomes, Human, Pair 3; D002897:Chromosomes, Human, Pair 7; D015342:DNA Probes; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008198:Lymph Nodes; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000473:pathology; D014066:Palatine Tonsil; D012189:Retrospective Studies; D014314:Trisomy
D015342:DNA Probes