CD5+ diffuse large B-cell lymphoma: a narrative review

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, and cell surface cluster of differentiation (CD) 5 expression may represent a distinct subset. Here, we provide a narrative review of CD5+ DLBCL to understand its clinical implications. Between 5–10% of DLBCL express CD5, making it an uncommon subset. Studies have variably shown that CD5+ DLBCL may be associated with increased age, high lactate dehydrogenase, B symptoms, extra-nodal sites, higher International Prognostic Index score, and advanced stage. CD5+ DLBCLs are more likely to express Bcl-2, MYC, and MUM1; a large proportion exhibit an activated B-cell (ABC)-like phenotype. The balance of studies generally supports an independent prognostic value of CD5 in DLBCL While more aggressive first-line regimens have been advocated for CD5+ DLBCL, including dose-adjusted R-EPOCH and autologous stem cell transplant, evidence to support these approaches is lacking; further study is warranted to identify the optimal treatment strategy for this disease entity.