A novel flow cytometric assay for detection of residual disease in patients with B-lymphoblastic leukemia/lymphoma post anti-CD19 therapy.

Background: Residual disease detection following therapy is an important prognostic variable in B-lymphoblastic leukemia (B-LL). Most flow cytometric strategies for detecting B cell malignancy utilize CD19 to identify B cells. With growing use of anti-CD19 targeted therapies, alternative strategies are needed for residual disease detection.

Expression of CD2 and CD25 on mast cell populations can be seen outside the setting of systemic mastocytosis.

Background: Systemic mastocytosis (SM) is a diagnosis made using clinical, laboratory, and histologic parameters. Aberrant CD2 and/or CD25 expression on mast cells provides one minor criterion for a diagnosis of SM. To validate a tube (CD45/CD117/CD2/CD25) for mast cell evaluation, flow cytometry (FC) on residual material from marrow aspirates samples submitted to the hematopathology laboratory was performed.