Prognostic significance of Bcl-6 protein expression DLBCL treated with CHOP or R-CHOP

Blood. 2006 Jun 1;107(11):4207-13. Epub 2006 Jan 31.

Prognostic significance of Bcl-6 protein expression in DLBCL treated with CHOP or R-CHOP: a prospective correlative study.
Winter JN, Weller EA, Horning SJ, Krajewska M, Variakojis D, Habermann TM, Fisher RI, Kurtin PJ, Macon WR, Chhanabhai M, Felgar RE, Hsi ED, Medeiros LJ, Weick JK, Reed JC, Gascoyne RD.
Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA. j-winter@northwestern.edu

Bcl-6 protein expression, a marker of germinal center origin, has been associated with a favorable prognosis in diffuse large B-cell lymphoma (DLBCL). To determine the prognostic significance of this marker when rituximab (R) was added to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy, we prospectively studied Bcl-6 protein expression by immunohistochemical staining of 199 paraffin-embedded specimens from patients enrolled in the US Intergroup phase 3 trial comparing R-CHOP to CHOP with or without maintenance R. In Bcl-6(-) patients, failure-free survival (FFS) and overall survival (OS) were prolonged for those treated with R-CHOP alone compared to CHOP alone (2-year FFS 76% versus 9%, P < .001; 2-year OS 79% versus 17%, P < .001). In contrast, no differences in FFS and OS were detected between treatment arms for Bcl-6(+) cases. In the multivariate analysis, treatment arm (CHOP versus R-CHOP) was the major determinant of both FFS (P < .001) and OS (P < .001) for the Bcl-6(-) subset, whereas the International Prognostic Index risk group was the only significant predictor of outcome among Bcl-6(+) cases. Bcl-2 protein expression was not predictive of outcome in either group. In this study, we observed a reduction in treatment failures and death with the addition of R to CHOP in Bcl-6(-) DLBCL cases only. Our finding that Bcl-6(+) cases did not benefit from the addition of R to CHOP requires independent confirmation.

Publication Types:

Clinical Trial
Clinical Trial, Phase III
Randomized Controlled Trial

PMID: 16449523 [PubMed - indexed for MEDLINE]