cell blocking

Cards (18)

  • Cell blocks

    Cytologic preparations that are processed as paraffin embedded blocks in a manner comparable to formalin-fixed paraffin-embedded tissue in surgical pathology
  • Cell blocks

    • Introduced in 1896 using colloidin embedding medium
    • Accepted in 1940s
    • CB techniques have evolved
    • Basic protocol similar in all techniques
  • Cell block application

    Can be used on any nongynecologic specimen, most commonly: Serous effusions, Pelvic/abdominal washes, Fine needle aspirations, Liquid based specimens
  • Procedure for cell block should be applied if there is visible sediment after being centrifuged
  • Cell block

    • Prepared for IHC and molecular studies
    • Increases the cellular yield and improves diagnostic accuracy
  • Plasma thrombin technique

    1. Cell button added to plasma and thrombin
    2. Cell material collects in clot
  • Agar or other gelatin techniques

    1. Concentrated sediment supported in agar or histogel
    2. Cell pellet formed then processed in paraffin
  • Collodion bag technique

    1. Concentrated sediment supported in agar or histogel
    2. Cell pellet formed then processed in paraffin
  • Tissue clot technique

    1. Allow clot to form in lumen of needle tip
    2. Clot transferred to formalin
    3. Prevents loss of diagnostic material
  • Shandon™Cytoblock™ method

    1. Uses cytocentrifugation to concentrate cells in cytospin
    2. Kit of cell block cassettes and reagents
  • Sedimentation cell block technique

    1. Transfer material to centrifuge tube
    2. Spin down to achieve a concentrated cell button
    3. Centrifuge set at 2400 RPM for five minutes
    4. Pour off supernatant
    5. Add buffered formalin
    6. Let material set in tube; 30-60 minutes
    7. Remove hardened cell button with a metal spatula
    8. The button placed on histology tissue paper that has been moistened with buffered formalin
  • Cell blocks cut at 8μm
  • If IHC needs to be performed it is noted on the QC sheet so appropriate number of sections can be cut and ready for IHC stains
  • Cassette is checked by two cytotechnology lab technologists for proper labeling – Quality Assurance
  • Cell block placed in formalin for at least six hours, documented on requisition with time stamp
  • Pap test

    • Thin Prep, Papanicolaou stain
    • Cell block, Hematoxylin and Eosin stain
  • Urine; bladder washing

    • Thin Prep: Papanicolaou stain
    • Cell block: Hemotoxylin & Eosin stain
  • a bloody urine cannon be used for cell blocking
    true or false
    false