Fnac techniques

fnac summery

1. FNAC Techniques DR Sandeep singh GMC. KNW

2. What is FNAC Fine needle aspiration cytology is a technique whereby cells are obtained from a lesion using a thin bore needle and smaers are made for cytopathological diagnosis. Technique is based on the fact that tumor cells are less cohesive and are easily aspirated. Rapid, reliable , less invasive and safe diagnostic procedure for superficial palpable masses. Under USG/CT guidance nonpalpable , deep masses can be aspirated.

3. Advantages It has many advantages over histopathology. Simple technique OPD based Quick and economical No need of anesthesia Multiple attempts or repeat procedure can be done without much inconvenience. Can eliminate tissue biopsy in many conditions Special techniques like IHC, Molecular techniques are also possible in FNAC material. High sensivity and specificity Less invasive

4. Limitations Significant loss of tissue architecture Difficult to differentiate in situ from invasive carcinoma Not possible to comment on capsular and lymphovascular invasion Considerable training is needed for interpretation.

5. Complications Minor hematoma formation Bleeding from site of aspiration Surgical emphysema in case of intrathorasic FNAC Rarely Anaphylactic reaction in case of rupture of hydatid cyst.

6. Comparison of FNAC and HP FNAC Histopatholgy Rapidity Very fast Takes time for processing of tissue , atleast one day Procedure OPD Require OT Cost Cheaper Costly Ancillary studies Possible like IHC, FC, Culture, Molecular studies Possible Sensivity and specificity Good Excellent, Gold standard

7. Contraindications Avoid in cases of bleeding diathesis. Avoid in case of hydatid cyst Avoid in case of aneurysmal cyst.

8. Applications Palpable mass lesions in : Lymph nodes Breast Thyroid Salivary glands Soft tissue masses Bones Non Palpable mass lesions in : Abdominal cavity Liver mass Pancreatic mass Retroperitoneal masses Thorasic cavity masses Lung mass Mediastinum mass Scrotal FNAC

9. Basic Techniques

10. FNAC Room Well ventilated room Well Lighted Preferably near to hospital OPD Equipped with examination bed, working table, and chair Privacy should be maintained

11. Steps of FNAC Read carefully FNAC requisition form filled by clinician ( site, patient details, Other relavant information) Identify the patient Take proper consent Take proper clinical history (Chief complaints, duration, relevant tests and imaging reports) Examine site of lesion

12. Technique

13. FNA with Aspiration Clean the lesion by spirit swab Fix the swelling by one hand to immobilize it. Insert the needle with syringe and piston handle attached with it. Pass the needle back and forth by moving the pistol handle. Create negative pressure Release the handle Take out the handle

14. 8. Remove the needle from syringe and take air in the syringe. 9. Reattach the needle with a syringe. 10. Push the aspirate out of the syringe to a fresh glass slide 11. Spread the material on the slide with the help of a spare glass slide. 12. Keep few slides in 95% ethanol for wet fixation. 13. Tell the patient to press the puncture site firmly with a piece of dry cotton for a few minutes.

15. FNAC without Aspiration Hold the swelling tightly Insert the needle in swelling Move the needle gently back and forth Withdraw the needle and attach it with a syringe full of air Push the material on glass slide

16. Dry aspirate smearing- one step

17. Wet sample smearing – two step Dry sample smearing Wet sample smearing – two step in single slide Wet sample smearing – two step in two slides

18. Macro appearance of stained smears smear of ‘dry’ sample ; cell clusters seen as blue dots, evenly spread; Smear of ‘wet’ sample by two-step smearing; mainly blood at top end, cell clusters concentrated and evenly spread in the thin mid portion; C, D poorly prepared smears of bloody material, partly dried or clotted before smearing.