This invention provides methods and arrays related to a gene expression-based survival predictor for DLBCL patients, including patients treated with the current standard of care, which includes chemotherapy and the administration of Rituximab. The invention provides a method of predicting the survival outcome of a subject suffering from diffuse large B cell lymphoma (DLBCL) that includes obtaining a gene expression profile from one or more DLBCL biopsy samples from the subject. The gene expression profile, which can be derived from gene expression product isolated from the one or more biopsy samples, includes an expression level for each gene in a germinal center B cell (GCB) gene expression signature and each gene in a stromal- 1 gene expression signature.