fine needle aspiration cytology by rahul raj
TRANSCRIPT
GENERAL COSIDERATION
The purpose of FNA to obtain diagnostic material for cytological study from organs that do not shed cells spontaneously. The bonemarrow, spleen, liver, breast, thyroid gland and lymph nodes are typical targets of the diagnostic procedure.
Sampling of tumors by means of narrow gauge needle was first described in 1930 in USA and become popular in late 1950s.
Sophisticated radiological imaging, computed tomography(CT), ultrasonography(USG),and image intensified fluoroscopy have been added to this method to perform FNA more accurately and precisely.
CLINICAL SKILLS REQUIRED
Familiarity with general anatomy eg thyroid vs other neck swelling
Ability to take a focused clinical history
Sharp skill in performing physical examination eg solid vs cystic, benign vs maligant lesions
Clinical skill required -2Good knowledge in normal cellular elements from various organs and tissue and how they appear on smears eg fats cells vs breast tumor cells
Comprehensive knowledge of surgical pathology
Medical technologist may be quite helpful with the aspiration service , ensuring that the smears are prepared and fixed and materials for cell block, immunocyto- or histochemistry , os well as other specialized techniques handled appropriately.
MATERIALS REQUIRED
1. Needle 21 G /27 G
2. Disposable syringe 10 – 20 ml
3. New glass slides
4. Syringe handle
5. Toluidine blue
6. Coplin jar
7. Spirit swab
8. Cotton gauge / dry swab
9. Adhesive tap
10. Pencil
11. Tooth picks
12. Waste disposable containers (blood stained products , non stained products)
13. FNAC reporting form
14. Bed
15. Table
16. Tray for carrying the slides
PROCEDURE
Principle
The negative pressure created within the syringe by aspiration holds the tissue against the sharp cutting edge of the needle. So that the tissue will be cut by the cutting end of the needle and accumulates with in the lumen of the needle / syringe tip
Procedure cont…
1. Put the clean glass slides on the table
2. Fill the coplin jars with ethanol
3. Explain the procedure to the patient and get the written consent
4. Place the patient on the aspiration table in supine position or any position which will expose the desired aspiration site
5. Expose the aspiration site
6. Clean the site with spirit swab from center outwards in concentric fashion
7. Leave the area to dry
Procedure con……
8. Open the syringe from the plastic wrapper and the needle to the syringe tip
9. Check the syringe by aspirating , air in and out of the syringe , put the needle in the syringe holder
10. Prick the lump by vertical technique, in which the needle is perpendicular to the skin
11. Aspirate the lump by pulling the piston, Rotate the needle and continue to aspirate. Move the back and forth and aspirate
Procedure con…….
12. If the lump is big change the direction of the needle and again aspirate
13. if the lesion is huge, multiple sites aspiration may be needed
14. Stop the aspiration, Let the piston go to its resting position, withdraw the needle
15. Put a dry swab/cotton gauze over the aspiration site and put an adhesive tap. Ask the patient to press the site for 5-10 min.
16. Put a drop of aspirate on the surface of a clean glass slide 2cm away from the end of the slide
Procedure con….
17. Immediately, spread the material on the slide by holding the slide with one hand and putting the flat surface of an another glass slide over the material and move it smoothly, gently and swiftly to the other end of the slide by applying gentle pressure
18. Slides planned for papanicolaou stain are subjected into ethanol so that the aspirated material is totally submerged in the alcohol solution
19. Slides planned to giemsa stain are left to dry in open air
20. Slides planned for immunocyto or histo should be prepare in pretreated(albumenized) slides or pre-coated adhesive slides prepared for the designated techniques.
DOCUMENTATION1. Date on which the tests done
2. Fixative used for wet smear
3. Name of the pathologist/physician/radiologist performing the test.
4. Name of the laboratory personnel assisting
5. Clinical diagnosis
6. Transfer the slide to the staining table in cytopathologylaboratory
7. Date of preparation of fixative
1. Grease free and clean slides should be used
2.A good quality 10ml or 20ml syringe should be used to create sufficient negative pressure to aspirate tissue
3.An experienced technologist or laboratory personnel should perform the staining procedure
Fixatives and stains
1. Dried smear are stained by Romanowsky staining method, especially May Grunwald-Giemsa
2. Other stains can be applied according to the need of diagnosis e.g.Gram`s ,Z.N stain, PAS, Alcian blue stain
3. Wet fixed smear by papanicolaou stain
4. 1.5% glutaraldehyde fixative solution for EM study
Complication of FNACFNA is considered one of the safest invasive diagnostic procedures though complication were estimated at 0.03% of cases
Complications of the FNAC of superficial masses include needle track seeding; pnuemothorax with breast, axilary, and supraclavicular masses, transient acute swelling(thyroid) hematomas, and histological alterations.
More serious and sometimes life threatening complications may occur with aspiration of deep organs. In the chest , these includes pnuemothorax, massive hemorrhage.
COMPARISON
SURGICAL BIOPSY
FNAC
•DIAGNOSIS•DIAGNOSTICDIFFICULTY•ANESTHETIC•LENGTH OF PROCEDURE•REPORT AVAILABLE
Histo pathologicalNarrow
YesMore than 5 min
2-4 days
Cyto pathologicalBroad
No(rare)Less than 5 min
2-4 hrs
•FALSE POSITIVE•COST•SPECIMEN OBTAINED•TRAUMA
NoneRelatively highIn operating theatreyes
RareEconomicalAs out patientLittle if any