CD56+/CD4+ Lymphomas and leukemias are morphologically, immunophenotypically, cytogenetically, and clinically diverse

• Published in: American journal of clinical pathology Vol. 116; no. 2; pp. 168 - 176
• Main Authors: RAKOZY, Christiane K, MOHAMED, Anwar N, VO, Trieu D, KHATIB, Ghada, MICHAEL LONG, P, EILENDER, David, PALUTKE, Margarita
• Format: Journal Article
• Language: English
• Published: Chicago, IL American Society of Clinical Pathologists 01-08-2001
• Subjects: Adult; Aged; Biological and medical sciences; Bone Marrow - pathology; CD4 Antigens - analysis; CD56 Antigen - analysis; Fatal Outcome; Female; Flow Cytometry; Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; Hematologic and hematopoietic diseases; Humans; Immunohistochemistry; Immunophenotyping; Killer Cells, Natural - immunology; Killer Cells, Natural - pathology; Leukemia - genetics; Leukemia - immunology; Leukemia - pathology; Leukemia, Lymphocytic, Chronic, B-Cell - genetics; Leukemia, Lymphocytic, Chronic, B-Cell - immunology; Leukemia, Lymphocytic, Chronic, B-Cell - pathology; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Lymph Nodes - pathology; Lymphoma - genetics; Lymphoma - immunology; Lymphoma - pathology; Lymphoma, T-Cell - genetics; Lymphoma, T-Cell - immunology; Lymphoma, T-Cell - pathology; Male; Medical sciences; Middle Aged; Palatine Tonsil - pathology; Skin - pathology; Spleen - pathology; Human; Immunohistochemistry; Leukemia; Malignant hemopathy; Non Hodgkin lymphoma; Natural killer cell; Case study; Pathology; Phenotype; Lymphoproliferative syndrome; Morphology; Cytogenetics; Adult; Molecular biology; Elderly
• ISSN: 0002-9173; 1943-7722
• DOI: 10.1309/FMYW-UL3G-1D7J-ECQF

CD56, a neural adhesion molecule, is a marker of natural killer (NK) lymphocytes as well as a subgroup of CD8+ T cells. Normal lymphocytes with a CD56/CD4 phenotype are scarce. Physiologic increases may occur in patients with immunosuppression, chronic inflammation, and autoimmune disorders. We report 4 cases of lymphomas/leukemias with the unusual CD56/CD4 phenotype. Two were of T-cell and 2 of true NK-cell origin. The T-cell lymphomas had large granular lymphocyte morphologic features and splenomegaly. One patients had a benign course; the other died within months of the leukemia diagnosis. The 2 NK cell lymphomas had blastic morphologic features, initially involved skin, and had a very aggressive clinical course; 1 patient died of acute leukemia, and 1 had recurrence after bone marrow transplantation. Cytogenetic analyses did not show a consistent pattern of abnormalities. The NK lymphoma with acute leukemia had a t(2;5) but was CD30- and anaplastic lymphoma kinase negative. Although CD56+/CD4+ lymphomas/leukemias are a heterogeneous group, there may be a distinct subgroup of NK lymphoblastoid lymphomas of the skin, judging from our cases, as well as those previously reported.