Hematopathology Laboratory Specimen Handling
Peripheral blood, bone marrow aspirate
Peripheral blood and bone marrow aspirate specimens should be anticoagulated and transported at room temperature as quickly as possible to the Hematopathology Laboratory. For peripheral blood, in most cases, 10 mL is adequate for analysis; however, greater volumes may be required for peripheral blood samples with low white blood counts. For bone marrow, 1 ml of anticoagulated marrow from the first aspirate pull is sufficient. Larger volumes of marrow and post-first marrow aspirate pulls contain significant amounts of peripheral blood dilution and should be avoided. In the absence of a suitable marrow aspirate, a marrow biopsy may be submitted fresh in tissue culture media.
For flow cytometric testing, EDTA is the preferred anticoagulant, although heparin is also acceptable. Our testing does not require preservative-free heparin.
For molecular testing, EDTA anticoagulation should be used as heparin can interfere with the assays; therefore, when requesting both molecular testing and flow cytometry on a shared sample, use EDTA anticoagulation. If specimens for DNA based molecular testing will arrive in the laboratory greater than 24 hours after collection, please refrigerate the sample to preserve the integrity of the DNA. Please note that for BCR/ABL testing, 20 ml of blood are required and, as this is an RNA based assay, the specimen must be received within 24 hours of collection.
Specimen requirements and handling may vary depending on a number of clinical factors; therefore the laboratory should be consulted prior to obtaining the specimen in order to optimize the information to be gained. Please contact the laboratory for details.
CSF, pleural fluid, peritoneal fluid, vitreous fluid, etc
Fluids should be mixed with an equal volume of tissue culture media (we use RPMI 1640 with 10% fetal calf serum). At minimum 1 ml of fluid (and ideally more if possible) will be needed for analysis. A supply of tissue culture media may be obtained from the Hematopathology Laboratory.
Fresh Tissue Specimens
The following may be used as general guidelines for handling lymph nodes, as well as other tissues that are to be sent to the Hematopathology Laboratory. If additional questions arise, please contact the laboratory for more specific instructions. Lymph nodes or other tissues should be transported from the operating room to your laboratory in sterile saline or tissue culture media (we use RPMI 1640 with 10% fetal calf serum). A representative section of lymph node or tissue should be placed in tissue culture media (RPMI 1640 with 10% fetal calf serum) and transported to the Hematopathology Laboratory as soon as possible. A supply of tissue culture media may be obtained from the Hematopathology Laboratory. Specimens for immunophenotyping by flow cytometry should never be placed in fixative. If the specimen will take greater than 12 hours to reach the laboratory, it should be transported in RPMI on wet ice.
Frozen or paraffin embedded tissue for molecular studies
DNA-based testing can be performed on either frozen or paraffin embedded tissue as well as on fresh tissue. Decalcification and certain fixatives (such as B5) render the DNA unsuitable for molecular assays thus paraffin embedded tissue that has been exposed to these agents is unacceptable.
When sending slides for consultation please include a report and any available clinical information and history. If it is anticipated that immunohistochemical stains will be needed, please send a paraffin block along with the slides. Although a paraffin block is preferred, unstained paraffin sections on adhesive slides (charged or plus) may be sent instead. Please include the patient’s billing information with the request if the patient’s insurance is to be billed. If the patient billing information is not included the institution will be billed for services.
Last updated: 5/27/08