Ordering Guidance

This assay should not be used for diagnosing lymphocytic malignancies or evaluation of lymphocytosis of unknown etiology. For such cases, order LCMS / Leukemia/Lymphoma Immunophenotyping, Flow Cytometry, Varies, which includes a hematopathology review.

This assay can be used for absolute quantitation of B cells in patients with chronic lymphocytic leukemia.

While this assay can be used to follow patients on B-cell-depleting therapy, like rituximab (eg, Rituxan, Riabni) or ofatumumab (eg, Kesimpta), it may be more reasonable and financially viable to use CD20B / CD20 on B Cells, Blood (includes CD45, CD19 and CD20 markers).

Shipping Instructions

It is recommended that specimens arrive within 24 hours of collection. Collect and package specimen as close to shipping time as possible.

Necessary Information

Date and time of collection are required.

Specimen Required

Container/Tube: Lavender top (EDTA)

Specimen Volume: 3 mL

Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.

Additional Information: For serial monitoring, it is recommended that specimen collection be performed at the same time of day.