Diffuse large B-cell lymphoma is the most common primary splenic lymphoma. It may present as small discrete or large coalescing nodules that frequently extend into contiguous structures. Most are Bcl-6 positive. This example was composed predominantly of immunoblasts. Note the single prominent centrally located nucleolus in the tumor cells. A few non-neoplastic reactive lymphocytes are scattered in the background. These are CD3+ T-cells.