CELL BLOCK PREPARATION AND ITS IMPORTANCE
- 1. CELL BLOCK PREPARATIONAND ITS IMPORTANCE PRESENTED BY:-DR. SHUBHADIP GHOSH MODERATOR:- DR.PAYEL BANDYOPADHYAY
- 2. WHAT IS CELL BLOCK • It is prepared from cytological material so that it can be processed sectioned, stained and viewed as a histology section. • It can provide diagnostic information from cytology slides. • It is easier to do special stains and immunohistochemistry from a FNA specimen.
- 3. NEED FOR CELL BLOCK • It has both diagnostic specificity and sensitivity. • It requires minimum effort and is cost efficient. • Moreover tissue preserved in cell block can be stored easily.
- 4. MATERIALS REQUIRED FOR CELL BLOCK
- 5. METHODS OF CELL BLOCK PREPARATION Fixed sediment method Histogel method Gelatin embedding Bacterial agar method Plasma thrombin method Colloidion bag Cytospinning method Cell blocks from Millipore Automated preparation Albumin method
- 7. PLASMA THROMBIN METHOD Principle is to place cellular material in the clot. Very simple and cost effective. METHOD: Place specimen in the tube and centrifuge for 10 mins at 1650 rpm Discard supernatant For approximately 1ml sediment add 4 drops of plasma and 4 drops of thrombin and mix well Clot form 30-60 sec Place clot in the cassette containing formalin Routine histological processing
- 9. HISTOGEL METHODS The concentrated sediment is supported by a cell adjuvant (agar) Agar solidifies below 50 C and cell pellet can be obtained This is more time consuming method It creates an excellent block with various cells distributed in layers for best visualisation
- 10. PROCEDURE OF HISTOGEL METHOD Centrifuge the cell suspension Melt 4%agar by placing the tube of agar in a small beaker of water and heating in a microwave Add approximately 4ml of completely melted agar to the sediments in a centrifuge tube. Mix gently Refrigerate to get a cell button Place in a cassette and process routinely
- 11. COLLODION BAG TECHNIQUE Collodion, a liquid polymer nitrocellulose material is poured into a tube After coating the tube completely remove excess collodion and air dried for 8-10 mins in inverted position Formalin fixed specimen transfer to the coated tube and centrifugation done The bag is removed from the tube Placed in a cassette for tissue processing
- 13. CYTOSPINNING METHOD It is a method where machine centrifuge and collection of sediment on center of the slides. This method is useful for hypocellular specimen. The basic principle is to concentrate cells within a defined areas and a filter card between the chamber sample and the glass slide resulting in cell to slide adhesion.
- 15. Automated cell block preparation Cellient system • It is an automated cell block technology • It uses "vacuum assisted filtration" to capture and concentrate available cells • It collect specimens in methanol based solution
- 16. • The cellient automated cell block system concentrates, processes, and embeds loose cells into a paraffin block ready for sectioning. • Cells are concentrated into a well in the cassette by vacuum, and subsequent washes with alcohol and xylene fix and clear the specimen • • The cell button is the infiltrated with paraffin in the same cassette
- 17. AUTOMATED CELL BLOCK ANALYSER MACHINE
- 18. CELL BLOCK FIXATION Media includes … a. SALINE b. RPMI( Rosewell Park Memorial Institute) c. NAFS (Nathan Alcohol Formalin Substitute) d. Formalin e. Alcohol based (methanol /ethanol/isopropanol)
- 19. ADVANTAGES OF CELL BLOCK Cell block is simple , reproducible and readily available in routine labs. Increased cellularity Better morphological and architectural patterns Additional yield of cells ,thereby increasing diagnostic yield Unlimited storage of the samples Application of ancillary studies (ICC and molecular testing)
- 20. DISADVANTAGE OF CELL BLOCK Compared to routine smears takes longer time Distortion artifacts. Cellular loss in an already small specimen may occur during multiple transfers during processing
- 21. TAKE HOME MESSAGE Cell block contains aspirated materials embedded in paraffin that increases the diagnostic value of cytology . Cell block technique is sensitive and specific tool for diagnostic cytology . Combination of cell block to conventional cytology smears inadequacy of FNAC is reduced. It is a bridge between cytology and histopathology
- 22. REFERNCES 1.Bancroft’s Theory and Practice of Histopathological Techniques 2.Diagnostic Cytology by Pranab Dey
- 23. THANK YOU