SLL in Lymph Node : Immunophenotype
Higher magnification showing sheets of mature B lymphocytes in a lymph node involved with CLL/SLL. Immunophenotype: Multicolor flow cytometry shows the following results in a typical case: mature B-cell phenotype with weak monotypic surface immunoglobulin, CD5 coexpression, weak CD20, weak CD22, CD23, CD19, weak CD11c; negative for CD10, FMC7, and CD79b. About 2% to 7% of otherwise prototypic CLL cases lack CD5 expression. Other B-cell chronic lymphoproliferative disorders should be excluded before making the diagnosis of CD5-ve CLL.