Flow cytometric immunophenotyping of anaplastic large cell lymphoma

Area of Science:

• Hematopathology
• Immunology
• Oncology

Background:

• Anaplastic Large Cell Lymphoma (ALCL) diagnosis traditionally relies on histology and immunohistochemistry.
• Fine-needle aspiration (FNA) is an increasingly utilized alternative to lymph node biopsy.
• Flow cytometry is a key technique for analyzing FNA specimens in ALCL diagnosis.

Purpose of the Study:

• To review flow cytometry findings in ALCL cases.
• To evaluate the diagnostic utility of flow cytometry for ALCL.
• To assess the immunophenotypic characteristics of ALCL using flow cytometry.

Main Methods:

• Flow cytometry with 3-color or 4-color antibody panels was used for ALCL assessment.
• Cluster analysis with Paint-A-Gate software reanalyzed flow cytometry data.
• Immunohistochemistry was employed to assess anaplastic lymphoma kinase (ALK) status.

Main Results:

• Nineteen of 23 ALCL cases showed identifiable neoplastic cells via flow cytometry (11 ALK+, 8 ALK-).
• ALCL cells were typically CD30 and CD45 positive, often appearing large and CD45 bright.
• Distinct T-cell antigen expression profiles were observed between ALK(+) and ALK(-) ALCL cases.

Conclusions:

• Flow cytometry is a viable method for immunophenotyping ALCL.
• Neoplastic cells in ALCL may be sparse and located outside the typical lymphocyte gate.
• Cluster analysis software facilitates flexible gating strategies for ALCL cell identification and characterization.