Clinicopathologic Characteristics and Genomic Profiling of De Novo CD5 Positive Diffuse Large B-Cell Lymphoma: A Multicenter Retrospective Study in China

De novo CD5 positive diffuse large B cell lymphoma (CD5+ DLBCL) has poor survival in the era of immunochemotherapy. We conducted a multi-center retrospective study to explore the clinicopathologic characteristics, genomic profiling and prognostic elements of 61 CD5+ DLBCL and 60 CD5- DLBCL patients in China. In contrast with CD5- DLBCL, elderly onset, advanced stage, central nervous system (CNS) involvement, as well as MYC/BCL-2 and P53 overexpression were more prevalent in CD5+ DLBCL. In addition, most of CD5+ DLBCL patients were of non-germinal center B-cell-like (non-GCB) and activated B-cell-like (ABC) subtype according to immunohistochemistry and Lymph2Cx assay. Genetic analysis by next generation sequencing (NGS) showed the proportion of MCD subtype in CD5+ DLBCL was higher than that of CD5- DLBCL (50% vs 5%, p = 0.0007). Compared with CD5- cohort, CD5+ DLBCL patients showed poorer 5-year overall survival (OS) (70.9% vs 39.0%, p<0.001), independent of cell-of-origin and MYC/BCL-2, P53 and BCL-6 status. Multivariate analysis showed that age >76 years, advanced stage, CNS involvement and hypoalbuminemia were independent factors associated with poor prognosis in CD5+ DLBCL. In conclusion, CD5+ DLBCL conveyed poor prognosis and showed distinctive clinicopathologic characteristics and predominant genetic features of ABC and MCD subtypes.