Contrary to the belief that is held by many clinicians that aspirating the thyroid is an easy and simple task, the performers of FNC often commit several cardinal mistakes.

• The aspirates take too long and samples are diluted with blood

• The use of larger calibre needles improves blinding that obscures the cell sample.

• Inadequate Samples for a cellular sample of epithelial cells.

Therefore, I think that it is necessary to do a briefing to focalize some fundamental issues on FNC sampling of Thyroid.

Needle Caliber

Aspirations of the thyroid are best performed with 25 or 23 gauge needles by two experienced operators; a cytopathologist and ecographist. The use of larger calibre needles is wrong because they cause more bleeding and result in unreadable bloody aspirates . Also, the smallest calibre needles preserve the cytological architecture of the thyroid nodule and for the cytologist this is of paramount importance for the diagnosis of follicular lesion because the follicles and papillary features are more easily recognizable using the smallest .

Fine needle Cytology

　After insertion, the needle is rapidly moved in and out without suction. Because the thyroid is richly vascularized, the needle cytology must be performed as rapidly as possible, in about 2 seconds in order to avoid dilution of samples with blood .

The preparations have be smeared by a pathologist onto one glass slide, air dried and stained with Diff-Quick .

Preparation of Smears

I recommend following the Swedish school of cytology and favour air dried smears fixed in methanol and stained with hematologic stains. The preparations have be smeared by a pathologist onto one glass slide, air dried and stained with Diff-Quick and microscopically evaluated immediately while the patient waits and , only if the aspirate is inadequate for accurate diagnosis , should the patient be re-aspirated. The needle should be washed by aspirating 2 ml of physiologic solution which is then collected into a tube . The material can then be used for molecular testing.

The advantage of this technique is:

1. The short preparation and staining time and excellent quality of nuclear features.

2. The sample is adequate to facilitate a correct cytologic diagnosis

3. It is possible to perform V600- Braf Test on the material collected for molecular test on indeterminate sample .

4. The inadequate sample disappears.

Molecular Biology

On indeterminate cytology diagnosis, the cellular material collected for molecular testing can be selected by centrifugation and used for DNA extraction.

Extraction

DNA can be obtained with a salting-out method [7]. Purity can be assessed by spectrophotometry (Biophotomaker, Eppendorf), while the degree of integrity can be evaluated with electrophoresis using 100 ng of DNA extract.

Ultrasound-guided FNAB is more accurate if the thyroid nodule is not a large one. 

thanks for the honest answer Guiseppe!

but, how can I recognize the expertize of a cytologist?

 I apologize for having responded late.

It is a correct question ,Jasmid. I introduce myself.  I am a dedicated, full time cytopathologist ( a professional hybrid according to Prof. LG Koss).  Therefore it is necessary that there is a medical doctor dedicated to the cytology. You can host a cytopathologist that educate your personal.

In one month you will have a good assistant.

Thank you for the interesting discussion. I agree that an experienced cytopathologist is needed. But I also emphasize the importance of team approach. At our university hospital, we have a weekly combined medico-surgical thyroid outpatient clinic to discuss problematic cases. The team is supported by an experienced ultrasonographer and a senior cytopathologist.