SLUCare Physician Group's Hematopathology/Flow Cytometry Laboratory recently introduced the region's first 10-flow cytometry process. What does that mean to the average person? Initially, not a lot, but to cancer doctors and leukemia and lymphoma patients, it means faster and more precise diagnosis and monitoring of disease.
Multicolor cytometry capitalizes on the latest laser, filter and detector technologies
to enable pathologists to simultaneously detect up to 10 fluorescent signals, or abnormalities.
Previously, labs were limited to scanning four fluorescent signals at a time.
Ten-flow cytometry paints a highly accurate diagnostic picture that can detect abnormal cell presence at very low levels. It can produce same-day results, lessening a patient's anxiety while waiting for results.
Studies must be performed on live cells of blood, bone marrow, body fluids, fine needle aspirates or fresh tissue. Specimen requirements can be found below
Specimen Requirements
Peripheral Blood Samples
Peripheral blood samples should be drawn in a sodium heparin or EDTA tube and kept at room temperature
(22-28°C) until testing. Between one and eight milliliters of blood is required, depending
upon the leukocyte count; a 5-ml sample is normally adequate. Samples should not be
refrigerated; they must be stored at room temperature. Samples must be delivered to
this laboratory as soon as possible or within 4 hours after collection, using transporters,
couriers, or overnight delivery services. Immunology peripheral blood samples received
more than 72 hours after collection will be rejected, as well as clotted, excessively
hemolyzed, refrigerated or frozen specimens. Samples drawn in lithium heparin or ACD
are not acceptable. CBC results drawn at the time of the flow specimen should be sent
with the requisition.
Bone Marrow Samples
Bone marrow samples should be drawn in a sodium heparinized syringe and transferred to a green
top (sodium heparin) tube for transport. The sample must be kept at room temperature
until testing. EDTA tubes are acceptable, but they must be less than 4 hours old when
received. ACD and lithium heparin are not acceptable. Between 1 and 3 ml of bone marrow
is required. Stability, storage, and transport of these samples are the same as that
for peripheral blood. CBC results drawn at the time of the flow specimen should be
sent with the requisition.
Lymph Node or Fresh Biopsy Tissue
Lymph node or fresh biopsy tissue is acceptable. To ensure that adequate cells are
available for flow cytometry, the tissue should be ≥ 1-2 cm square. Smaller samples
are acceptable but may limit the number of markers that are able to be performed.
The sample should be placed immediately in cold (2-8°C) RPMI media or on cold saline-soaked
gauze and transported immediately on ice (not frozen) to the laboratory for testing.
Receipt should be within 4 hours. If longer transport or overnight storage is required,
the tissue should be kept in cold RPMI media and transported in the RPMI media on
wet ice. Samples that have been exposed to fixatives (such as formalin or alcohol)
are unacceptable for testing, as are samples that have been previously frozen or are
frozen when received.
Body Fluids
Body fluids (pleural, ascites, pericardial, cerebral spinal or CSF) and WASHINGS (fine needle aspirates or lung lavages) are acceptable for flow cytometric analysis if the cell number is sufficient. The minimal volume of sample required is 3 mls; however, depending upon cell number, this volume may not be sufficient for flow cytometric analysis. If the specimen is bloody, sodium heparin may be added to the specimen at collection. The sample should be kept at room temperature and delivered immediately to the laboratory. Receipt should be within 4 hours.
Processed samples of hematopoietic progenitor cell (HPC) harvests (apheresis, bone marrow) are acceptable for flow cytometric analysis of CD34+ stem cells. Samples should be sent at room temperature within 4 hours after processing.
The Flow Cytometry Laboratory maintains an extensive panel of monoclonal antibodies.
The service uses state-of-the-art Beckman Coulter Cytomics FC 500 and Gallios flow cytometers. Studies can be performed on peripheral blood, bone marrow, body fluids, fine needle aspirates or fresh tissue. A smear, cytospin or touch preparation is made of each specimen to confirm a suitable specimen and to tailor a specific antibody panel. A preliminary clinical diagnosis is required on the requisition.