CD56 Negative Aggressive T Cell Large Granular Lymphocytic Leukemia.

Area of Science:

• Hematology
• Oncology
• Immunology

Background:

• T cell large granular lymphocytic leukemia (T-LGLL) is a chronic lymphoproliferative disorder characterized by clonal expansion of cytotoxic T lymphocytes.
• This condition typically follows an indolent course, with observation or low-dose chemotherapy as primary treatment options.
• Aggressive T-LGLL is rare and often associated with the expression of NK cell-associated antigens like CD56.

Observation:

• The study presents a case of T-LGLL in a 38-year-old female patient.
• This specific case was characterized by the absence of CD56 expression on the malignant T cells.
• The patient experienced a fatal outcome despite the CD56-negative status.

Findings:

• The case demonstrates that T-LGLL can follow a fatal, aggressive course even in the absence of CD56 expression.
• This finding challenges the common association of aggressive T-LGLL solely with CD56 positivity.
• The patient's T cells were positive for CD3 and CD8, consistent with cytotoxic T lymphocytes.

Implications:

• This case underscores the heterogeneity of T-LGLL and the potential for aggressive disease presentation irrespective of CD56 status.
• It suggests that CD56 negativity does not exclude the possibility of a rapidly progressing and fatal T-LGLL.
• Further research is warranted to identify alternative prognostic markers and optimize therapeutic strategies for non-CD56 expressing aggressive T-LGLL.