Burkitt lymphoma is immunophenotypically different from Burkitt-like lymphoma in young persons.
BACKGROUND
Burkitt-like lymphoma (BLL) is a provisional category of B-cell lymphoma which is morphologically intermediate between Burkitt lymphoma (BL) and large B-cell lymphoma (LBCL). The clinical significance of this morphology is controversial.


METHODS
We examined 41 cases of pediatric B-cell lymphoma by immunohistochemistry for proteins associated with proto-oncogenes c-myc, BCL-2 and BCL-6 and a subset of cases (with adequate slides) for a proliferation-associated marker (Ki-67) and for apoptosis (Apop-Tag). Sixteen cases of BLL, thirteen cases of BL and twelve cases of LBCL were examined.


RESULTS
Our results showed BCL-6 expression in 16 of 16 BLL, 4 of 13 BL, and 9 of 12 LBCL; c-myc expression in 14 of 15 BLL, 9 of 13 BL, and 12 of 12 LBCL; and BCL-2 expression in 2 of 16 BLL, 9 of 13 BL, and 6 of 12 LBCL. Mean apoptotic index for BLL was 10.3% (n = 6); for BL was 17.1% (n = 5); and for LBCL was 10.9% (n = 6). Ki-67 was diffusely reactive in all cases tested. There was a significantly higher proportion of BLL than BL which expressed BCL-6 (P = 0.0001).


CONCLUSIONS
Labeling for BCL-6 distinguishes BLL from BL. It is likely that in children in North America, BLL is biologically distinct from BL and more closely resembles a subset of LBCL.
Hutchison
R E
RE
State University of New York Health Science Center, Syracuse, USA.
Finch
C
C
Kepner
J
J
Fuller
C
C
Bowman
P
P
Link
M
M
Schwenn
M
M
Laver
J
J
Desai
S
S
Barrett
D
D
Murphy
S B
SB
D000293:Adolescent; D014408:Biomarkers, Tumor / Q000032:analysis*; D002051:Burkitt Lymphoma / Q000175:diagnosis / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D004268:DNA-Binding Proteins / Q000032:analysis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis / Q000473:pathology*; D008297:Male; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000032:analysis*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D051560:Proto-Oncogene Proteins c-bcl-6; D012680:Sensitivity and Specificity; D014157:Transcription Factors / Q000032:analysis*
D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051560:Proto-Oncogene Proteins c-bcl-6; D014157:Transcription Factors