US-guided needle biopsy of the right breast lesion was performed; analysis was carried out with a Leica microscope (dm2000 led, Objective: x63), Leica ICC50HD camera and Leica Acquire software for Macbook pro 16’ 2,6 GHz 6-Core Intel Core i7; histologic examination (Figs. 1 and 2) showed a diffuse large B-cell lymphoma, not otherwise specified (DLBCL, nos), CD19+, CD20+, of germinal center origin according to immunohistochemical algorithms (CD10+, BCL6+, IRF4/MUM1+, FoxP1+, LMO2+, HGAL+), with high proliferation index (MIB-1 80%). Here, IRF4 is linked to diffuse large B-cell lymphoma.