Intermediate lymphocytic lymphoma: immunophenotypic and cytogenetic findings

Area of Science:

• Hematology
• Oncology
• Immunology

Background:

• Intermediate lymphocytic lymphoma (ILL) is a type of non-Hodgkin lymphoma.
• Understanding its immunophenotypic and cytogenetic profile is crucial for accurate classification and diagnosis.

Purpose of the Study:

• To conduct a detailed immunohistologic and cytogenetic analysis of 12 cases of intermediate lymphocytic lymphoma.
• To define the characteristic immunophenotype and chromosomal abnormalities associated with ILL.
• To evaluate the relationship between ILL and other lymphocytic lymphomas.

Main Methods:

• Immunohistologic analysis using a panel of antibodies to define cell surface markers.
• Cytogenetic analysis to identify clonal chromosome abnormalities.
• Comparison of findings with established criteria for lymphocytic lymphomas.

Main Results:

• The characteristic immunophenotype included surface IgM and IgD positivity, with specific expression of BA1, B1, B4, Leu 14, Leu 1, and HLA-DR, and negativity for B2 and common acute lymphocytic leukemia (CALLA) antigen.
• Clonal chromosome abnormalities were found in 10 out of 12 cases.
• Abnormalities of chromosomes 11 or 12 were present in 9 cases, including translocations involving 11q and 14q32, trisomy 12, and abnormalities of 12q. One case showed a 7;9 translocation.

Conclusions:

• The immunophenotypic and cytogenetic findings suggest a close lineage relationship between intermediate lymphocytic lymphoma and small lymphocytic lymphoma/chronic lymphocytic leukemia.
• Distinct clinical, cytologic, and architectural features warrant the classification of intermediate lymphocytic lymphoma as a separate category within the International Working Formulation.
• This study provides key diagnostic markers for intermediate lymphocytic lymphoma, aiding in its differentiation from other lymphoid malignancies.