Composite lymphoma of follicular B-cell and peripheral T-cell types with distinct zone distribution in a 75-year-old male patient: a case study

• Published in: Human pathology Vol. 76; pp. 110 - 116
• Main Authors: Tanaka, John, Su, Pu, Luedke, Catherine, Jug, Rachel, Yang, Lian-He, Deak, Kristen, Rapisardo, Sarah, Zhang, Yang, Delos Angeles, Marc, Xie, Yi, Wang, Endi
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-06-2018; Elsevier Limited
• Subjects: Antigens; B-cell lymphoma; Chemotherapy; Composite lymphoma; Follicular lymphoma; In situ; Lymphatic system; Lymphocytes; Lymphoma; Stains & staining; T-cell lymphoma; Tumors; Zone distribution; Zone distribution; Follicular lymphoma; Composite lymphoma; In situ; T-cell lymphoma; B-cell lymphoma
• ISSN: 0046-8177; 1532-8392
• DOI: 10.1016/j.humpath.2017.11.017

Composite lymphoma of T-/B-cell type is rare, and follicular lymphoma composite with peripheral T-cell lymphoma (PTCL) has not previously been reported. We report such a case with both neoplastic components displaying a unique zone of distribution. A 75-year-old male patient presented with generalized lymphadenopathy. Sections of axillary lymph node demonstrated potentially 2 clonal processes, PTCL with aberrant CD20 expression and follicular lymphoma. Interestingly, the 2 neoplastic components were confined to their respective classic distribution zones, with PTCL occupying the interfollicular areas and follicular lymphoma residing in follicles. Both populations were detected by flow cytometry, but their immunophenotypes were insufficient to define clonality. Nonetheless, biclonality was demonstrated by lymphoid receptor gene rearrangement analyses. Molecular cytogenetics showed IGH/BCL2 fusion in the follicular lymphoma and amplification of IGH gene or trisomy/tetrasomy 14 in the PTCL. The current case underscores the complexity of composite lymphoma and advocates a multimodal approach to establishing the diagnosis.
•This is the first case of composite follicular lymphoma and PTCL to be reported.•PTCL demonstrates aberrant CD20, which is rare in mature T-cell lymphoma.•The 2 neoplastic components are confined to their respective classic distribution zones.•The biclonality of T-/B-cell lymphoma is demonstrated by IG/TCR gene rearrangement analyses.•FISH shows IGH/BCL2 in follicular lymphoma and amplification of IGH or trisomy/tetrasomy 14 in PTCL.