Intravascular T-cell lymphoma: A rare, poorly characterized entity with cytotoxic phenotype

Area of Science:

• Hematology
• Neurology
• Oncology

Background:

• Intravascular T-cell lymphomas are uncommon and poorly understood hematologic malignancies.
• Central nervous system (CNS) abnormalities can manifest in rare lymphoma subtypes.

Observation:

• A 62-year-old woman presented with progressive CNS abnormalities.
• Radiological imaging revealed multifocal ischemia and vasogenic edema in cortical and subcortical regions.
• Brain biopsy identified abnormal cytotoxic T-cells (CD3+, CD8+) within the vessel lumens.

Findings:

• The abnormal T-cells were intravascularly localized, lacking expression of CD2, CD4, CD5, CD7, and CD30.
• Flow cytometry and immunohistochemistry did not detect these cells in peripheral blood or bone marrow.
• Molecular studies confirmed a clonal T-cell population in both the brain and bone marrow, with no other organ involvement.

Implications:

• This case suggests a distinct T-cell lymphoma subtype characterized by intravascular cytotoxic T-cells.
• The findings underscore the importance of integrating clinical, radiological, immunophenotypic, and molecular data for diagnosis.
• Understanding these rare lymphomas is crucial for developing targeted therapeutic strategies.