Blastoid and common variants of mantle cell lymphoma exhibit distinct immunophenotypic and interphase FISH features.
OBJECTIVE
The recognition of blastoid variant (BV) of mantle cell lymphoma (MCL) is based on morphological criteria. Our aim was to analyse 18 MCL cases including four BV-MCL for their clinicopathological features, proliferation index, cyclin D1 and CDK4 expression and interphase fluorescence in-situ hybridization (FISH) pattern.


RESULTS
BV-MCL versus common MCL was characterized by a shorter overall duration of response after first-line therapy (11 months versus 28 months) and shorter overall survival (20 months versus 42 months). Interphase FISH showed a t(11;14) fusion pattern in all MCL tested cases. However, the four blastoid cases were characterized by extra copies of CCND1 signals. Using additional probes of chromosomes 11, 18, 21, these signals were shown to be the result of hypotetraploidy and not of a specific amplification of the normal or the translocated CCND1 allele. Moreover, the BV-MCL cases were characterized by a combined high percentage of cells expressing cyclin D1 and/or CDK4 with a proliferation (MIB-1-Ki67) index above 50%. Such features allowed the recognition of areas of large cell transformation in the case of secondary BV-MCL.


CONCLUSIONS
Since distinction between BV and common MCL is of clinical relevance, our data underline the need to add phenotypic and cytogenetic criteria to cytomorphology for a better recognition of BV-MCL.
Parrens
M
M
Department of Pathology and Tumour Biology, CHU Bordeaux and Equipe 2406, University of Bordeaux 2, Bordeaux, France. marie.parrens@chu-bordeaux.fr
Belaud-Rotureau
M-A
MA
Fitoussi
O
O
Carerre
N
N
Bouabdallah
K
K
Marit
G
G
Dubus
P
P
de Mascarel
A
A
Merlio
J-P
JP
D000328:Adult; D000368:Aged; D018951:Antigens, CD20 / Q000032:analysis; D018956:CD5 Antigens / Q000032:analysis; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics; D019938:Cyclin D1 / Q000032:analysis / Q000235:genetics; D051358:Cyclin-Dependent Kinase 4 / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007399:Interphase / Q000235:genetics; D019394:Ki-67 Antigen / Q000032:analysis; D051917:Leukosialin / Q000032:analysis; D008214:Lymphocytes / Q000473:pathology*; D020522:Lymphoma, Mantle-Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D014411:Neoplastic Stem Cells / Q000473:pathology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D014178:Translocation, Genetic; D016896:Treatment Outcome
D018951:Antigens, CD20; D018956:CD5 Antigens; D019394:Ki-67 Antigen; D051917:Leukosialin; D019938:Cyclin D1; D051358:Cyclin-Dependent Kinase 4