抄録
A 31-year-old woman presented with a solid 4×4 cm right breast tumor on echography, which further showed an irregular border and a heterogenous internal echo. Aspiration cytology showed clusters of atypical small cells indicating invasive ductal cancer, so modified radical mastectomy was done. Stamp cytology showed atypical lymphoid cells without clusters, indicating malignant lymphoma. The histological diagnosis was diffuse mixed B-cell malignant lymphoma.