Although new strategies as chimeric antigen receptor T-cells (CART), bispecific monoclonal antibodies and new combinations with anti-CD19 (tafasitamab) plus lenalidomide or antibody drug conjugates (polatuzumab) plus bendamustine and rituximab are increasing the therapeutic armamentarium in relapsed/refractory (R/R) DLBCL (3), the search of new reliable predictive and prognostic biomarkers that could guide clinical management and eventually point to new therapeutic targets is extremely relevant and necessary. Here, CD19 is linked to diffuse large B-cell lymphoma.