Composite Epstein-Barr Virus-associated T-lymphoblastic and Peripheral T-cell Lymphomas: A Clonal Study

Area of Science:

• Virology
• Oncology
• Immunology

Background:

• Epstein-Barr virus (EBV) is associated with various lymphoid malignancies.
• T-lymphoblastic lymphoma (T-LBL) is an aggressive lymphoma originating from immature T-cells.
• Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) represents a heterogeneous group of mature T-cell neoplasms.

Observation:

• A patient initially diagnosed with T-lymphoblastic lymphoma (T-LBL) harbored a clonal Epstein-Barr virus (EBV) genome.
• At relapse, the patient presented with axillary lymphadenopathy diagnosed as peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS).
• Southern blot analyses confirmed that both the T-LBL and PTCL-NOS were clonally identical, indicating a common origin.

Findings:

• The initial T-LBL cells expressed CD21, which facilitated EBV entry.
• The relapsed PTCL-NOS cells lacked CD21 expression.
• The clonal identity between T-LBL and PTCL-NOS suggests a transformation or evolution of the lymphoma.

Implications:

• This case suggests a potential pathway where EBV infects immature CD21-positive T-cells, initiating lymphomagenesis.
• The emergence of CD21-negative PTCL-NOS from CD21-positive T-LBL implies a possible phenotypic switch during disease progression.
• Understanding this evolution could offer insights into T-cell lymphoma pathogenesis and EBV-driven malignancies.