Thyroid cancer - Radiofrequency - Puncture - Diagnosis - Treatment
Thyroid cytopuncture
The thyroid nodule is a frequent and benign pathology in the majority of cases,
Ultrasound coupled with color Doppler and elastography makes it possible to specify the characteristics of the nodules, and constitutes an effective guide for a diagnostic puncture and for monitoring and makes it possible to reduce the number of excisions of benign nodules.
But it is operator dependent and its reliability requires good cooperation with a pathologist trained in cytodiagnosis.
Each patient with a thyroid nodule is a potential candidate for a fine needle puncture and must benefit from a clinical, biological (TSH-T4) and radiological (ultrasound) evaluation before this movement.
Cytopuncture has been established for years as a diagnostic method for thyroid nodules which are very frequent... and almost always benign.
Initially performed blind, by simple palpation, it is more readily performed today under ultrasound guidance.
It is a reliable, rapid and minimally invasive technique, associated with very low morbidity.
It makes it possible to reduce surgical acts by improving the selection of patients to be operated on.
Indications for thyroid cytopuncture
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Thyroid nodule as a function of EU TIRADS score and nodule size.
Score EU TIRADS 5
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Family history of CMT or MEN2
Basal calcitonin elevated twice.
Nodule at risk:
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at least 1 of the ultrasound criteria for suspicion score EU TIRADS 5.
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focal uptake on PET FDG
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Volume increase > 6 mm per year
According to (Durante et al. JAMA 2015; 313(9): 326-35 Nakamura H et al. Thyroid 2015; 7: 804-11 Lim DJ et al. Endocrinol Metab 2013; 28: 110-118)
15% to 30% of nodules increase in volume and the appearance of a new nodule in 10% of patients.
The increase in volume is generally slow = or < 3 mm per year on average for the solid part of the nodule.
The increase of 6 mm per year is considered rapid growth but this increase is not a sign of malignancy.
Also the size stability does not confirm the benignity of the nodule.
In the case of multinodular goiters, the sonographer selects the nodules to be punctured, ie those larger than 5mm that are sonographically suspicious and/or the largest (more than 2cm) in the absence of a suspicious nodule.
According to the 2017 EU TIRADS score:
The indication for fine needle aspiration of nodules according to the size and the score.
Fine needle aspiration technique
Fine needle aspiration is a minimally invasive procedure, performed using a fine needle 25 to 27 gauge).
The puncture is very painless and does not require local anesthesia but the patient often apprehends the gesture because of the anxiety-provoking cervical location.
For children or patients distressed by the procedure, local anesthesia with an EMLA type patch is possible.
More recently formal or conversational hypnosis is a valuable aid before and during the gesture in case of necessity.
Asepsis
A protector probe is required
Skin asepsis of the puncture area
Single-use sterile needle and syringe (25-27G).
During the examination, use liquid Betadine or sterile gel instead of non-sterile gel to ensure a good image.
The sterile field is not necessary due to the exceptional nature of post-puncture infection
The puncture
The capillarity sampling technique remains the most reliable technique, which allows non-traumatic sampling for the cells and less haemorrhagic; by placing the needle in the nodule and making small rotational movements for 5 – 10 seconds
If the liquid does not rise in the needle, aspiration with a 5ml syringe is necessary.
The number of passages depends essentially on the size of the nodule and the quantity of the liquid taken
A sub-centimeter nodule with 4-5 blades obtained by capillarity is more than enough to reliably analyze the nodule, on the other hand a nodule of 3 cm, it takes between 2 and 3 passages or 5-6 blades without hemorrhagic character when spreading the blades.
Cytology results
The interpretation of cytopuncture has been standardized for years with the BETHESDA Score.
There are 6 possible diagnostic categories with increasing risk of malignancy.
According to (Durante et al. JAMA 2015; 313(9): 326-35 Nakamura H et al. Thyroid 2015; 7: 804-11)
The first post-puncture control of a classified thyroid nodule (BETHASDA 2) on cytology is between 6 and 18 months depending on the appearance of the remaining parenchyma and then increase the interval in the event of ultrasound stability (2-3-5 years).
Complications
Complications of fine needle aspiration are minor in the majority of self-limiting cases and do not require specific management.
The most common complication is pain, and sometimes anxiety can lead to vagal discomfort.
Intranodular hemorrhage in essentially cystic nodules is sometimes responsible for a cervical gene with an increase in nodular volume.
A perithyroid hematoma is possible due to the rich thyroid vascularization.
The superficial venous branches of the jugular vein are often crushed by the compression of the probe and the counter-lateral rotation of the head makes it possible to avoid a hematoma superficial.
Thyroid fine needle puncture is considered to have a low risk of bleeding.
Management of platelet aggregation inhibitors and anticoagulants before thyroid cytopuncture
(low risk of bleeding).
Protocol applied in the radiology department at the University Hospital of NIMES.
1 . Platelet aggregation inhibitors.
KARDEGIC – ASPIRIN: no stop at 75 mg and relay by 75 mg in the event of a dose of 160mg for 3 days.
PLAVIX no stopping.
2 . Injectable anticoagulants.
LMWH: LOVENOX – INNOHEP- FRAXIPARINE.
Stop treatment 12 hours before the puncture if the dose is preventive.
Stop treatment 24 hours before the puncture if the dose is curative.
HNF: HEPATIN-CALCIPARIN.
Stop 8 to 12 hours before the puncture and resume the next day in the event of a preventive dose and after 48 hours in the event of a curative dose.
3 . VKAs
PREVISCAN-COMADINE-SINTRON.
Not taken the day before the puncture and resumed the next day.
4 . Direct acting anticoagulants (NACO)
PRADAXA-XARELTO-ELIQUIS.
No taking the night before or the morning of the puncture.
Resumption the day after the puncture.
Management of platelet aggregation inhibitors and anticoagulants before thyroid radiofrequency
(moderate hemorrhagic risk).
Protocol applied in the radiology department at the University Hospital of NIMES.
1 . Platelet aggregation inhibitors
KARDEGIC – ASPIRIN: no stop at 75 mg.
KARDEGIC 160 mg relay with 75 mg for 3 days before the act.
PLAVIX stop 5 days before the procedure and switch to KARDEGIC 75 mg for 4 days before the procedure.
2 . Injectable anticoagulants.
LMWH: LOVENOX – INNOHEP- FRAXIPARINE.
Stop treatment 12 hours before the puncture if the dose is preventive.
Stop treatment 24 hours before the puncture if the dose is curative.
HNF: HEPATIN-CALCIPARIN.
Stop 8 to 12 hours before the act and resume the next day in the event of a preventive dose and after 48 hours in the event of a curative dose.
3 . AVKs.
PREVISCAN-COMADINE-SINTRON.
Stop 5 days before the act, relay with Heparin at a curative dose 3 days before the act.
4 . Direct acting anticoagulants (NACO).
PRADAXA-XARELTO-ELIQUIS.
Stopped 5 days before the act, relay with heparin at a curative dose 12 hours after stopping NOAC.
Resumption the day after the puncture.
Conclusion
For years, cytopuncture of thyroid nodules has been a reference method for selecting nodules with a potential risk of thyroid cancer.
Thyroid nodules with a BETHESDA score of 5 and 6 on cytology must be operated on.
Thyroid nodules with a BETHESDA score of 4 and 3 on cytology, to be redone the cytopuncture in 3 – 6 months according to the EU TITADS score.
Thyroid nodules with a BETHESDA score of 2 on cytology, ultrasound monitoring 6 months, 1 year, 2 years, 3 years and 5 years depending on the evolution and stability of the nodule).
Thyroid nodules with a BETHESDA 1 score, redo the cytopuncture in 3 – 6 months according to the EU TIRADS score.