The lymph node core biopsies show a proliferation of atypical lymphoid cells, forming diffuse sheets. No follicular structures are seen. The atypical lymphocytes are large in size. They have enlarged clefted and hyperchromatic nuclei, prominent nucleoli and scanty cytoplasm. The large atypical lymphoid cells are CD20, bcl-6 and MUM1 positive. The Ki-67 index is about 50%. They are CD3, CD5, CD10, CD23, Cyclin D1 and bcl-2 negative. The features are those of diffuse large B-cell lymphoma, not otherwise specified, with activated B-cell-like phenotype.
Supraclavicular bx: Diffuse large B-cell lymphoma.