Clinicopathological diagnosis of Lennert lymphoma: a case report and review of the literature

• Published in: Diagnostic pathology Vol. 19; no. 1; pp. 111 - 7
• Main Authors: Ding, Shun, Chen, Jiao, Su, Jiajun, Liu, Jiewen, Yin, Weihua, Qi, Fengjie
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 16.08.2024; BioMed Central; BMC
• Subjects: Abdomen; Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Bcl-6 protein; Biomarkers, Tumor - analysis; Bone marrow; Cancer; Case report; Case reports; CD4 antigen; CD8 antigen; Cell proliferation; Chemotherapy; Corticosteroids; CXCL13 protein; Cyclophosphamide; Cytotoxicity; Dehydrogenases; Diagnosis; Epirubicin; Epithelioid histiocytes; Etoposide; Female; Gene expression; Health aspects; Humans; Hyperplasia; Immunohistochemistry; Infections; Lennert lymphoma; Literature reviews; Lymphatic system; Lymphocytes; Lymphocytes T; Lymphoma; Lymphoma, T-Cell, Peripheral - diagnosis; Lymphoma, T-Cell, Peripheral - pathology; Middle Aged; Morphology; Mutation; Non-Hodgkin's lymphomas; Patients; PD-1 protein; Predictive Value of Tests; Prednisone; PTCL-NOS; Remission; RS-like cells; T cells; T-cell lymphoma; Tomography; Treatment Outcome; Tumor cells; Vincristine; Viruses; Ann Arbor Michigan; United States > US; PTCL-NOS; Case report; Lennert lymphoma; Epithelioid histiocytes; RS-like cells
• ISSN: 1746-1596; 1746-1596
• DOI: 10.1186/s13000-024-01533-x

Lennert lymphoma (LL) is a variant of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS), also known as a lymphoepithelioid variant of PTCL. Because of the rarity and lack of clear-cut diagnostic criteria, LL is susceptible tomisdiagnosis. Although previously diagnosed with LL might be reclassified and evaluated with the advent of of molecular and/or genetic findings, cytomorphology and immunohistochemistry are still the key to give rise to correct diagnosis. We report a case of a patient who was diagnosed as LL based on cytomorphology and immunohistochemistry. Routine stain (Hematoxlin and Eosin-H&E) revealed tumor cells were mainly small to medium-sized CD4(+) T cells, the CD8 +/TIA-1 + cytotoxic cells were less minority, no expressions of follicle helper T cell markers (CD10, BCL6, PD1, CXCL13, ICOS) or CD21(+) hyperplastic FDC network, or proliferation of high edndothelial venules were noted; however, numerous epithelioid histiocytes are noted in the background and scattered EBV(+) cells were also present. The patient was achieved complete remission after six courses of chemotherapy with cyclophosphamide, epirubicin, vincristine, etoposide, and prednisone regimen. She was followed for 5 years without recurrence or progression. Classic LL is not difficult to diagnose by cytomorphology and immunohistochemistry, and the mutation profiles can be helpful to distinguish LL from other lymphomas.