FNAC is a minimally invasive procedure used to diagnose palpable masses. It was first described in 1930 and became popular in the 1950s. FNAC samples lesions in the breast, thyroid, soft tissues and other accessible areas like the testicles, prostate, bones and lungs. It requires clinical skills like anatomy knowledge and physical exam proficiency. FNAC has advantages of not requiring anesthesia, being low cost, allowing repeat sampling with few complications. The procedure involves aspiration of the mass and smearing cell samples on slides for microscopic examination.

1. FINE NEEDLE ASPIRATION
CYTOLOGY
Suramya Babu
BSC mlt 2013

2. FNAC
• It was first described in 1930 in USA & become
popular in late 1950s
• FNAC is most often for diagnostic of palpable
mass lesions
• Palpable lesions commonly sampled are : breast
masses , enlarged thyroid , &superficial soft
tissue masses.
• Testicles,palpable abdominal lesions, prostate,
pelvic organs, bone & joint spaces,
lungs,retroperitoneum & orbit are the other
sites & lesions accessible to FNAC.

3. Contraindication
• Bleeding
• Obstructive
• Emphysema or pulmonary hypertention
• Pancreatitis
• Bacteraemia/septicemia

4. 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 malignant lesions
• Good knowledge in normal cellular elements
from various organs & tissue and how they
appear on smears. Eg :- fats cells vs breast tumor
cells
• Comprehensive knowledge of surgical pathology

5. Advantages
• No anesthesia is required .
• No hospitalization is required .
• It is easy to perform and is least invasive
• It is economical.
• Cysts can be aspirated easily & diagnosed with this
procedure.
• Multiple attempts or repeating the procedure are possible
without inconvenience.
• The results are extremely satisfactory in good hands
• It is a cost effective procedure
• The exact cytological diagnosis is available before definitive
surgery is planned

7. FNA consist of four coordinates steps
1. Palpation
2. Aspiration
3. Smear preparation
4. microscopy

8. Principle
• The negative pressure created 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 / syringetip

9. DOCUMENTATION
1) 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
cytopathology laboratory
7) Date of preparation of fixative

11. Procedure
• Put the clean glass slides on the table
• Fill the coplin jars with isopropyl alcohol
• Explain the procedure to the patient & get the
written consent
• Place the patient on the aspiration table in
supine position or any position which will
expose the desired aspiration site

12. • Clean the site with spirit swab from center outwards in
concentric fashion , leave the area to dry
• Put the needle in the syringe holder
• Prick the lump by vertical technique , in which the
needle is peripheral to the skin
• Aspirate the lump by pulling the piston , rotate the
needle & continue to aspirate . Move the back & forth
& aspirate

13. Frozen needle guide which maximizes
accurate needle placement while
minimizing the risk of self puncture
• Fine needle range from 20 to 24 guage (0.6mm to
0.9mm)outer diameter are used.
• 25 or 24 gauge disposable needles of 25mm
length are used for lymph nodes and in children.

14. • If the lump is big change the direction of the
needle and again aspirate.
• If the lesion is huge, multiple sites aspiration
may be needed.
• Stop the aspiration, let the piston go to its
resting position, withdraw the needle.
• Put a dry swab/ cotton gauze over the
aspiration site and put an adhesive tap. Ask
the patient to press the site for 5-10min.
• Put a drop of aspirate on the surface of a clean
glass slide 2cm away from the end of the slide.

15. FIXATIVES AND STAINS
• Dried smear are stained by Romanowsky
staining method, especially May Grunwald
Giemsa.
• Other stains can be applied according to the
need of diagnosis e.g.; Gram’s, ZN stain, PAS,
Alcian blue stain
• Wet fixed smear by Papanicolaou stain.
• 1.5% glutardehyde fixative solution for EM
study.
• Fixatives commonly used are 90% isopropyl
alcohol, 95% ethyl alcohol.

16. Rapid stain- toluidine blue
• Toluidine blue offers excellent cytological
details for the preliminary identification of the
lesion and to decide on the adequacy of the
material for definitive diagnosis on FNAC
slides.
• At least 6 clusters are needed for the
assessment of cellularity.

17. Feature Wet fixed Air dried
staining papanicolaou,H &E Leishman,MGG
Cell size Comparable to
tissue sections
exaggerated
Nuclear detail excellent fair
nucleoli Well demonstrated Not always
discernible
Cytoplasmic details Poorly
demonstrated
Well demonstrated
Stromal
components
Poorly
demonstrated
Well demonstrated
Partially necrotic
materials
Single intact cells
,well defined
Cell details poorly
defined

18. FNAC Complications
• FNA is considered one of the safest invasive
diagnostic procedures though complications
were estimated at 0.03% of cases.
1)Hematomas
2)Infection
3)Pneumothorax

19. SURGICAL BIOPSY FNAC
Diagnosis histopathological Cytopathological
Diagnostic difficulty narrow Broad
Anaesthetic yes No
Length of procedure More than 5 min Less than 5min
Report available 2-4 days 2-4hrs
False positive none Rare
Cost Relatively high Economical
trauma yes Little if any

20. Radiological aids in FNAC
• Plane X-ray film: for lesion in bone and for
lesions in the chests
• CT:for lesions in chest and abdomen
• USG guidance: which allows direct
visualization of needle placement in real time
and free from radiation hazards
• Image amplified fluoroscopy