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Special Collection Procedures for Specimens

 

Specimen Requirements and Handling

Peripheral Blood

  • Venous blood 2-3 mL (1 mL minimum) in a sodium heparin (green top) tube
  • Do not use lithium or ammonium heparin
  • Send to lab as soon as possible at room temperature

Bone Marrow

  • 0.5 cc of marrow in a pre-warmed (37°C) vial of RPMI
  • Peripheral smear, marrow smear, and CBC should accompany the sample
  • Send to lab as soon as possible at room temperature
Solid Tissue
  • Clean the area with alcohol 
  • Remove a 1-2 mm sliver of skin 
  • Place in appropriate transport media
  • Send to lab as soon as possible at room temperature
Amniotic Fluid
  • Discard the first few ml of the sample (reduces maternal contamination) 
  • Place 20-25 ml of sterile amniotic fluid in a sterile container
  • Send to lab as soon as possible at room temperature
  • A consent form must accompany the sample

 

 

Special Fixatives

 

Z-5 fixative
Z-5 fixative is used in histology and surgical pathology.  It is a useful fixative for lymph node and bone marrow specimens.  The solution consists of formaldehyde, zinc, buffer and indicator in ethanol or reagent alcohol and water.  Pre-filled containers of this material are available from Incyte Diagnostics. Bone marrow biopsies and clot sections can be placed directly into the Z-5. Larger specimens (such as lymph nodes) should ideally be cut into 0.2 to 0.3 cm slices before placing them into the fixative. A volume of 15 parts fixative for 1 part tissue is recommended.

 

RPMI Medium (Roswell Park Memorial Institute)

This material is not a fixative, but a preservative nutrient medium of balanced osmolality. It is used mainly to transport specimens to a central facility for either flow cytometry (DNA ploidy, S-phase analysis, immunophenotyping), or cytogenetic studies. This fluid is only for the short-term stabilization of tissues, and specimens in this preservative must be transported to the laboratory as soon as possible. RPMI should be stored in a refrigerator and discarded if it loses its usual pink color. After the specimen has been added, however, it should be shipped at room temperature.

 

Electron Microscopy Fixative (Graham Karnovsky’s Fixative)

This material is used specifically to prepare tissues for electron microscopy. A small amount of tissue (usually a tumor or renal biopsy) must first be cut into slices not more than 1 mm thick before they are placed in EM fixative.

 

Hormone Receptor Analysis

The evaluation of estrogen and progesterone receptors provides important prognostic information in breast tumors, as well as certain other neoplasms (e.g., endometrial carcinoma). Quantitative evaluation of these receptors on formalin fixed and paraffin embedded tissues is performed.

 

Cytogenetics

These studies are generally performed on either placental-fetal tissue (to detect hereditary disorders) or on hematopoietic tumors (for prognostic and diagnostic information). Specimens must be fresh, sterile, and kept at room temperature. They should be transported to the laboratory as soon as possible, avoiding excessive drying or temperature extremes. For all specimens other than peripheral blood, a special cytogenetics transport media (RPMI) is required and can be obtained from the laboratory.