Flow Cytometric Patterns of CD200 and CD1d Expression Distinguish CD10-Negative, CD5-Negative Mature B-Cell Lymphoproliferative Disorders.

Objectives: The importance of distinguishing mature B-cell lymphoproliferative disorders (B-LPDs) is highlighted by the distinct treatments used for and varying prognoses seen in association with these different diseases. Immunophenotyping allows for accurate and efficient differentiation of many B-LPDs. Recently, we showed that CD200 is highly expressed in hairy cell leukemia (HCL) but not in marginal zone lymphoma (MZL), lymphoplasmacytic lymphoma (LPL), or hairy cell leukemia-variant (HCL-v). Here, we assessed the usefulness of a flow cytometric panel combining CD200 and CD1d with CD25, CD103, and CD11c to distinguish CD10-, CD5- B-LPDs.

Methods: We analyzed the expression of CD200 and CD1d by flow cytometric analysis in 79 cases of CD10-, CD5- mature B-LPDs.

Results: Distinct patterns of CD200 and CD1d expression were seen in the examined B-LPDs. HCL showed bright positivity for CD200 along with positive staining for CD1d, whereas HCL-v showed low levels of expression for both markers. LPL demonstrated positive staining for CD200 in combination with dim to negative staining for CD1d. In contrast, MZL was commonly positive for CD1d and negative for CD200.

Conclusions: Flow cytometric analysis of CD200 and CD1d, along with CD25, CD103, and CD11c, can aid in the diagnosis of CD10-, CD5- mature B-LPDs.