Specimen Collection

Bone Marrow Aspiration and Biopsy

Proper collection and preparation of bone marrow is critical to the study of a variety of hematologic and neoplastic disorders. A bone marrow profile includes a CBC, manual differential, and a reticulocyte count. Please send an EDTA whole blood specimen for this testing. Never send a dry Bone Core sample as it will desiccate and be useless for any study, including slides/morphology. For a printable Bone Marrow and Cytogenetics form refer to the link below for the Oncology work-up requisition.

Oncology Work-up Requisition

BONE MARROW - Aspirate Smears
  1. Sodium Citrate (3%) is the anticoagulant of choice for making aspirate smears. Heparin or EDTA anticoagulants should NOT be used since they may produce staining artifacts.
  2. The physician obtaining the aspirate should dispense part of the aspirate into the container with the citrate anticoagulant. The remaining aspirate should be allowed to clot in the syringe.
  3. At least 10 squash (crush) preparations should be made from the anticoagulated aspirate. Send the remaining citrated aspirate to the laboratory.
    a) Squash (crush) preps are good for finding tumor cells present in rare numbers, cytochemical stains and giving an overall picture of the marrow pattern.
    b) Push preps (thin smears) are preferred for examining cytologic details and for performing differential counts, if requested.
BONE MARROW - Microbiology Cultures
  1. When cultures have been ordered on the bone marrow, at least 2ml of the bone marrow aspirate should be placed in a SPS Vacutainer® tube or Wampole ISOLATOR™ 1.5 microbial tube (yellow top)
  2. It is recommended that the aspiration be from a different site than the aspiration for routine studies.
BONE MARROW - Chromosomes/ PCR/ Cytogenetic Studies
  1. Place at least 2-3 ml of the bone marrow aspirate in both a Sodium Heparin Non-Gel tube and EDTA Lavender top tube.
  2. Invert the tube several times to allow for proper specimen and anticoagulant mixing.
  3. Include a signed Advanced Beneficiary Notice with this testing request.

Note: If a Bone Core biopsy (not the liquid aspirate) is being sent for Cytogenetics (Chromosomes and or FISH), the preferred media is RPMI. This is a nutrient, and it keeps the sample moist and prevents desiccation. An alternative to RPMI is a Green top Sodium Heparin tube. Do not use EDTA for Cytogenetics. RPMI is ALWAYS the best for bone marrow core biopsies.

BONE MARROW - Flow Cytometry
  1. Place as much bone marrow aspirate as possible into a sterile EDTA tube.
  2. Invert the tube several times to allow for proper specimen and anticoagulant mixing.

Note: If a Bone Core biopsy (not the liquid aspirate) is being sent for Flow cytometry, the preferred media is RPMI. This is a nutrient, and it keeps the sample moist and prevents desiccation. An alternative to RPMI is a Green top Sodium Heparin tube. EDTA could also be used for Flow cytometry but NOT cytogenetics. RPMI is ALWAYS the best for Flow cytometry on bone marrow core biopsies.

BONE MARROW - Aspirate, Histology Sections
  1. Remove the clotted aspirate from the syringe and place it in B-5 fixative. Please indicate the fixative on the specimen label.

Note: DO NOT send in the core biopsy in B5 or formalin IF it may be used for Flow cytometry or Cytogenetics (Chromosomes and or FISH).  B5 and or formalin are ONLY used when the core biopsy will be made into slides for morphologic study under the microscope. RPMI is ALWAYS the best for Flow cytometry on bone marrow core biopsies.

BONE MARROW - Bone Biopsy and Touch Preparations
  1. If there is a dry tap and the physician obtains only a needle biopsy, touch preparations should be made using the biopsy. Touch - Do Not press the biopsy to clean slides.
  2. Place the biopsy in approximately 20ml of B-5 fixative or formalin.
  3. Biopsy specimens are essential for the accurate quantitation of cellularity for routine studies. They are especially useful for diagnosis of aplastic anemia, granulomatous disease of the marrow, myelofibrosis, primary or metastatic disease, malignant lymphoma and TTP. They are also useful in following the effect of chemotherapeutic agents on the marrow.

CAUTION: Over fixation yields brittle tissue blocks and results in poor sections. Do NOT delay in getting the material to the laboratory.

Note: DO NOT send in the core biopsy in B5 or formalin IF it may be used for Flow cytometry or Cytogenetics (Chromosomes and or FISH).  B5 and or formalin are ONLY used when the core biopsy will be made into slides for morphologic study under the microscope. RPMI is ALWAYS the best for Flow cytometry on bone marrow core biopsies.

BONE MARROW - Patient History and Specimen Labeling
  1. A bone marrow patient history form, provided by RML, should accompany all requests for bone marrow interpretation. This form lists information required by the pathologist in his interpretation of the slides.
  2. All specimens should be labeled with the patient’s first and last name, date of collection and the fixative used. Please indicate specimen type on each container/tube.
BONE MARROW - B-5 Fixative
  1. Advantage: Excellent cytologic detail
  2. Disadvantage: Requires immediate processing. Submit to RML within 2 hours of collection. Specimen cannot be used later for Flow cytometry or Cytogenetics (Chromosomes and or FISH).
  3. Immediately prior to use, combine 6 ml of formalin with 54 ml of 6% Mercuric Chloride stock solution and mix well. The resulting solution should be used immediately.

WARNING! B-5 Fixative contains mercuric chloride and must be handled with care. Avoid contact with skin, clothing and eyes. It is advisable to wear glasses when handling B-5. B-5 fixative requires a special mode of disposal. Do NOT pour down the sink. Returned unused material to the laboratory for disposal.

Note: DO NOT send in the core biopsy in B5 or formalin IF it may be used for Flow cytometry or Cytogenetics (Chromosomes and or FISH).  B5 and or formalin are ONLY used when the core biopsy will be made into slides for morphologic study under the microscope. RPMI is ALWAYS the best for Flow cytometry on bone marrow core biopsies.