A 68-year-old woman with a history of discoid lupus erythematosus presented with multiple subcutaneous nodules on the breast and upper extremities. An incisional biopsy was performed due to concern for subcutaneous panniculitis-like T-cell lymphoma (SPTCL). Hematoxylin-eosin staining showed a dense lymphoid infiltrate (panel A: original magnification ×40; panel C: original magnification ×400) rimming adipocytes, with scattered plasma cells involving the deep dermis and subcutaneous tissue (panel B:

Leonard N. Yenwongfai, Ivo M. B. Francischetti; Prominent expansion of EBV + large B cells obscuring follicular helper T-cell lymphoma. Blood 2024; 144 (25): 2682. doi: https://doi.org/10.1182/blood.2024026909 An older adult patient presented with diffuse rash, lymphadenopathy, and hepatosplenomegaly. Hematoxylin and eosin staining of a skin biopsy revealed proliferation (panel A, 20× lens objective) of medium to large lymphocytes (panel B, 200× lens objective), expressing CD20 (panel C, 200× lens

Leonard N. Yenwongfai, Ivo M. B. Francischetti; Prominent expansion of EBV + large B cells obscuring follicular helper T-cell lymphoma. Blood 2024; 144 (25): 2682. doi: https://doi.org/10.1182/blood.2024026909 An older adult patient presented with diffuse rash, lymphadenopathy, and hepatosplenomegaly. Hematoxylin and eosin staining of a skin biopsy revealed proliferation (panel A, 20× lens objective) of medium to large lymphocytes (panel B, 200× lens objective), expressing CD20 (panel C, 200× lens

Simon Chevalier, Clémentine Legrand; B-cell acute lymphoblastic leukemia with MEF2D:: BCL9 rearrangement mimicking a Burkitt lymphoma. Blood 2024; 144 (19): 2067. doi: https://doi.org/10.1182/blood.2024026200 A 39-year-old woman presented with widespread lymphadenopathy, leukocytosis (25.1 × 10 9 /L), anemia (hemoglobin, 9.6 g/dL), thrombocytopenia (23 × 10 9 /L), and elevated lactate dehydrogenase (8594 U/L). The peripheral blood smear showed 46% atypical cells with finely clumped chromatin, medium to

St. Jude Children’s Research Hospital Qingsong Gao, Christine J. Harrison; B-ALL with intrachromosomal amplification of chromosome 21 in a carrier of the Robertsonian translocation rob(14;21)c. Blood 2024; 143 (25): 2672. doi: https://doi.org/10.1182/blood.2024023923 A 6-year-old girl was diagnosed with B-lineage acute lymphoblastic leukemia (B-ALL), with classic morphology and immunophenotype. Fluorescence in situ hybridization detected 4 to 5 RUNX1 signals in 48% of cells (panel A; RUNX1, red signals;