Improved Algorithm for Classifying Diffuse Large B-Cell Lymphoma

Researchers at the University of Nebraska have developed a new immunohistochemical algorithm that can accurately classify diffuse large B-cell lymphoma (DLBCL) into its molecular subtypes. The new algorithm, which uses five specific antibodies, has a 93% concordance rate with gene expression profiling (GEP) classification, outperforming the previous algorithm developed by Hans and coworkers. The study validates the algorithm's accuracy in a separate set of 63 DLBCL cases treated with rituximab plus CHOP, showing a significant difference in 3-year overall survival between the germinal center B-cell-like (GCB) and activated B-cell-like (ABC) subtypes.

Key Takeaways:

The new algorithm uses five specific antibodies: GCET1, CD10, BCL6, MUM1, and FOXP1, which closely approximate the GEP classification with 93% concordance.
The algorithm is robust within the range of observer variance, as indicated by perturbation analysis.
The new algorithm predicts a significant difference in 3-year overall survival between GCB and ABC subtypes: 87% vs. 44% (P < 0.01).
The study validates the algorithm's accuracy in a separate set of 63 DLBCL cases treated with rituximab plus CHOP.
The algorithm is expected to facilitate risk stratification of DLBCL patients and future DLBCL research using archival materials.
The study's results have the potential to improve the treatment and outcome of DLBCL patients.

Statistics:

93% concordance rate between the new algorithm and GEP classification.
87% 3-year overall survival rate for GCB subtype.
44% 3-year overall survival rate for ABC subtype (P < 0.01).
63 DLBCL cases treated with rituximab plus CHOP used to validate the new algorithm.
47 GCB and 37 ABC subtypes in the validation set.

Sources:

Choi et al. (2009). A New Immunostain Algorithm Classifies Diffuse Large B-Cell Lymphoma into Molecular Subtypes with High Accuracy. Clinical Cancer Research, 15(17), 5494-5502.
American Association for Cancer Research. (Publishers of Clinical Cancer Research).
W.C. Chan, University of Nebraska, Medical Center, Dept. of Pathology & Microbiology, 983135 Nebraska Med Center, Omaha, NE 68198, USA.