The document discusses the thyroid FNA procedure and diagnostic categories. It provides details on: - Performing thyroid FNA under ultrasound guidance using a 25 gauge needle with 3-4 passes. - Preparing direct smears, cytospins, cell blocks and liquid-based preparations from the aspirated material. - The Bethesda system for reporting thyroid cytopathology which includes 6 diagnostic categories and their associated cancer risks to guide clinical management. - Key cytologic features that help diagnose common thyroid lesions and cancers.

1. THYROID FNA
DR ZAHID MAHMOOD
FCPS(HISTOPATHOLOGY)
KING EDWARD MEDICAL UNIVERSITY
LAHORE

2. Thyroid FNA Procedure
• US guidance
• 25 gauge needle
• 3-4 passes
FNA Thyroid

3. Fine Needle Non Aspiration (FNNA) biopsy
showing needle, position & direction for biopsy.
Immediately after FNA, firm pressure
is applied to biopsy sites

4. Technique and Equipment (Contd…)
Biopsy Procedure without aspiration

5. Difference between core and FNA biopsy

6. Needle is removed from syringe Air is aspirated into the syringe
Aspirated material is expelled onto the slides & smears are prepared

7. Technique and Equipment (Contd…)
Material in the hub of needle

8. Thyroid FNA
Preparations
• Direct smears
- Air-dried, Diff Quik stained
- Ethanol fixed, Pap stained
• Cytospins
• Cell block
• Liquid-based preparation
FNA Thyroid
DQ
PAP
CB
Core Biopsy

9. Thyroid FNA
The Cell Pattern Approach
• CELLS
– Arrangement
– Nuclear features
– Cytoplasmic features
• COLLOID
• BACKGROUND FEATURES

10. Clues to Diagnosis!
• More colloid
….more likely benign
• More cells
…. more likely neoplastic

11. The Bethesda System for Reporting Thyroid
Cytopathology: 6 Diagnostic Categories
• I. NONDIAGNOSTIC or UNSATISFACTORY
•
• II. BENIGN
• III. ATYPIA OF UNDETERMINED SIGNIFICANCE or FOLLICULAR
LESION OF UNDETERMINED SIGNIFICANCE
• IV. FOLLICULAR NEOPLASM or SUSPICIOUS FOR A FOLLICULAR
NEOPLASM
• - specify if Hürthle cell (oncocytic) type
• V. SUSPICIOUS FOR MALIGNANCY
• VI. MALIGNANT
•

12. TBRTC:
Relationship to Clinical Algorithms
Category Cancer Risk Management
Nondiagnostic or
Unsatisfactory
1-4% Repeat FNA with U/S
Benign <1-3 % Follow-up clinically
AUS, FLUS ~5-15 % Repeat FNA
Follicular Neoplasm, or
Suspicious for a Follicular
Neoplasm*
20-30 % Lobectomy
Suspicious for Malignancy
(usually papillary CA)
60-75 % Lobectomy or total
thyroidectomy
Malignant 97-99 % Total thyroidectomy
* Specify if Hürthle cell type

13. Thyroid FNA: made Easy
• Granulomatous Thyroiditis
Giant cells munching on colloid
• Hashimoto’s Thyroiditis
Lymphocytes and oncocytes
• Papillary carcinoma
Papillae, nuclei and cytoplasm
• Medullary carcinoma
Carcinoid and amyloid
• Anaplastic carcinoma
Ugly giant and spindle cells
• Follicular lesions?
Colloid vs. follicular cells

15. Follicular Neoplasm
CYTOMORPHOLOGY
• Marked cellularity
• Discohesion, single cells
• Predominantly microfollicles
and/or trabeculae
• Uniformly enlarged cells
• Crowding
• Scant colloid
• Marked nuclear atypia, mitosis
and necrosis is uncommon

16. Papillary carcinoma
Follicular variant

17. VI: Malignant
Papillary thyroid carcinoma
• Papillae- not very
common
• Sheets: flat or
syncytial
• Sheets/ clusters
with well defined
borders
• Clusters: 3-D

18. VI: Malignant
Medullary thyroid carcinoma
Plasmacytoid cells Spindle cells

19. VI: Malignant
Anaplastic carcinoma

20. FNA Breast lesions (reporting Categories)
C-1 Inadequate
C-2 Benign
C-3 Atypia (probably benign)
C-4 Suspicious for malignancy
C-5 Malignant