Is. Lossos et al., Expression of a single gene, BCL-6, strongly predicts survival in patientswith diffuse large B-cell lymphoma, BLOOD, 98(4), 2001, pp. 945-951
Diffuse large B-cell lymphoma (DLBCL) is characterized by a marked degree o
f morphologic and clinical heterogeneity. Establishment of parameters that
can predict outcome could help to identify patients who may benefit from ri
sk-adjusted therapies. BCL-6 is a proto-oncogene commonly implicated in DLB
CL pathogenesis. A real-time reverse transcription-po lyme rase chain react
ion assay was established for accurate and reproducible determination of BC
L-6 mRNA expression. The method was applied to evaluate the prognostic sign
ificance of BCL-6 expression in DLBCL. BCL-6 mRNA expression was assessed i
n tumor specimens obtained at the time of diagnosis from 22 patients with p
rimary DLBCL. All patients were subsequently treated with anthracycline-bas
ed chemotherapy regimens. These patients could be divided into 2 DLBCL subg
roups, one with high BCL-6 gene expression whose median overall survival (O
S) time was 171 months and the other with low BCL-6 gene expression whose m
edian OS was 24 months (P = .007). BCL-6 gene expression also predicted OS
in an independent validation set of 39 patients with primary DLBCL (P = .01
). BCL-6 protein expression, assessed by immunohistochemistry, also predict
ed longer OS in patients with DLBCL. BCL-6 gene expression was an independe
nt survival predicting factor in multivariate analysis together with the el
ements of the International Prognostic Index (IPI) (P = .038). By contrast,
the aggregate IPI score did not add further prognostic information to the
patients' stratification by BCL-6 gene expression. High BCL-6 mRNA expressi
on should be considered a new favorable prognostic factor in DLBCL and shou
ld be used in the stratification and the design of risk-adjusted therapies
for patients with DLBCL. (C) 2001 by The American Society of Hematology.