High-grade B cell lymphoma, unclassifiable, with blastoid features: an unusual morphological subgroup associated frequently with BCL2 and/or MYC gene rearrangements and a poor prognosis.
OBJECTIVE
A subset of B cell lymphomas with blastoid features do not fit either as B lymphoblastic lymphoma/leukaemia or blastoid mantle cell lymphoma. Their classification is challenging, even with complete clinicopathological and genetic information. At a haematopathology workshop, experts had suggested the term 'high-grade B cell lymphoma, unclassifiable, with blastoid features', and recommended further studies.


RESULTS
We describe the clinicopathological, immunophenotypic and cytogenetic findings of 24 high-grade B cell lymphomas, unclassifiable, with blastoid features. Fifteen patients presented de novo and seven patients had a history of lymphoma. Twenty patients (83%) presented with nodal disease. All tumours expressed pan-B cell antigens and 17 (89%) of 19 tumours assessed had a germinal centre B cell immunophenotype. Ten (63%) of 16 tumours assessed by fluorescence in-situ hybridization (FISH) had MYC rearrangement, 13 of 18 (72%) carried IGH-BCL2 and nine of 15 (60%) had both (double-hit lymphoma). The median overall survival was 1.1 years. Using 2008 World Health Organization criteria, 15 cases were classified as B cell lymphoma, unclassifiable, with features intermediate between diffuse large B cell lymphoma (DLBCL) and Burkitt lymphoma, and nine as DLBCL, small centroblastic variant.


CONCLUSIONS
High-grade B cell lymphomas, unclassifiable, with blastoid features are clinically aggressive with poor survival. Most neoplasms have a germinal centre B cell phenotype. MYC rearrangements and IGH-BCL2 are common, and ~60% are double-hit lymphomas.
Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Rashmi
R
Kanagal-Shamanna
L Jeffrey
LJ
Medeiros
Gary
G
Lu
Sa A
SA
Wang
John T
JT
Manning
Pei
P
Lin
Gerald M
GM
Penn
Ken H
KH
Young
M James
MJ
You
Francisco
F
Vega
Roland
R
Bassett
Roberto N
RN
Miranda
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000378:metabolism; D005260:Female; D015321:Gene Rearrangement; D019254:Genes, bcl-2; D016259:Genes, myc; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D007621:Karyotyping; D016393:Lymphoma, B-Cell / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011379:Prognosis
D015703:Antigens, CD