AblationofBenignThyroidNodules:Evidence,Guidelines,Meta-analyses,andApproaches

AuhWhanPark,MD

InterventionalRadiology

UniversityofVirginia

Disclosures

Auh Whan Park:Norelevantfinancialrelationshipswithanycommercialinteresttodisclose

Brandnamesareincludedinthispresentationforparticipantclarificationpurposesonly.Noproductpromotionshouldbeinferred.

Contents

1. HistoryofThyroidRFA

- Rationale

2.CurrentGuidelines

- Indications&Contraindications

3. Procedure&KeyTechniques

- Strategy

- Perithyroidallidocaininjection

- Trans-isthmicapproachandmovingshot

4. EfficacyandSafety

HistoryofThyroidAblation

Korean Society of Thyroid Radiology (KSThR)

- 2009: 1st recommendations for thyroid RFA

- 2012: 1st guideline for thyroid RFA

Tipping Point

Re-emergenceofThyroidAblation

1. Aneedforthyroidpreservation

2.Advancedtechniques&equipment

3.Evidenceonclinicalefficacyandsafety

PrevalenceofThyroidNodulesGeneral

Population

USdetectable

nodule:19-68%

Autopsy:49%

Palpablenodule:

5-10%

Malignancy

1.2%lifetime

Autopsy:2.1%

Mortensen JD,et al, JCEM 15: 1270, 1955Ezzat et al, Arch Int Med 154:1828, 1994

NaturalHistoryofBenignThyroidNodules

• Changes in thyroid nodule size and volume

during the first 5 years of follow-up.

- No significant size increase

: 174 (11.1%) of 1567 : Grew

1188 (75.8%) of 1567 : Stable

205 (13.1%) of 1567 : Shrank

• Cancer diagnosis : rare

- 5 (0.3%) of 1567

* Incidental cancer at thyroidectomy

in a non-visualized nodule

** New nodule in 93(9.3%) patients

with one cancer

Durant et al. JAMA. 2015

BenignThyroidNodules

Symptoms

:Massorhormonaleffect/

(Cosmeticconcerns/Anxiety)

ThyroidHormone

Suppressive

Therapy

RadioactiveIodine:AutonomousFunctioningThyroidNodule(AFTN)

Surgery:

Lobar/TotalThyroidectomy

MinimallyInvasive&ThyroidPreservingProcedure?

ThyroidectomyVolumeandOutcomes

With a conservative assumption of 150,000 thyroidectomies per year in the USA

à Thyroidectomy for benign nodules : 150,000 x (63.3/100) = 94,950

Association of Surgeon Volume With Outcomes and Cost Savings Following ThyroidectomyJAMA Otolaryngol Head Neck Surg. 2016

Increases in thyroid nodule fine-needle aspirations, operations, and diagnoses of thyroid cancer in the United States. Sosa et al. Surgery 2013

BenignThyroidNodules

Symptoms

:Massorhormonaleffect/

(Cosmeticconcerns/Anxiety)

ThyroidHormone

Suppressive

Therapy

RadioactiveIodine:AutonomousFunctioningThyroidNodule(AFTN)

Surgery:

Lobar/TotalThyroidectomy

MinimallyInvasive&ThyroidPreservingProcedure?

Chemical/

ThermalAblation

ThyroidAblation:Tools

Ethanol Laser Radiofrequency HIFUMicrowave

Thyroid-dedicated probes

with FDA clearanceFDA clearance

AdvantagesofAblationinBenignThyroidNodules

Pros Cons

Nolife-longmedication:thyroid-preserving Gradualvolumereduction:follow-up

Nogeneralanesthesia:localanesthesiaonly- Immediaterecovery

Repeatsessionsinuntreatedportion- Largetumorormarginalregrowth

Lesscomplication:Safe

Nosurgicalscar:aestheticallypleasing

Noadmission:outpatient-based

Nodowntimeforwork:economical

GuidelinesforThyroidRFA• KoreanSocietyofThyroidRadiology(KSThR)

- 2009:1strecommendationsforthyroidRFA

- 2012:1stguidelineforthyroidRFA

- 2017:RevisedguidelineforthyroidRFA

• 2015:ThefirstItalianopinionstatement

• 2016:NationalInstituteforHealthandCare(NICE)inEngland

• 2019:�GoodClinicalPracticeRecommendations� forAustria

GuidelinesforThyroidRFAIndication Korea Italy Austria NICE AACESymptomaticorcosmeticproblem

O O O O O

Nonfunctionalorpred.solid(first-line)

O O - - -

Cystic/pred.cystic(EA:first-line)

O O - - -

AFTN(toxicorpre-toxic)vs.RAIorsurgery

O–Alternative- Less

effectiveinlargeAFTN

O-Refusalorinoperable-EffectiveinsmallAFTN

O-Notrec.Large(>15ml),

multifocalAFTN- -

Multinodulargoiter -Selective(refusalor

inoperable)- - -

Requiredbiopsyresults FNACNB FNA FNA FNA FNA

Twobenignresults O O O O O

Onebenignresult AFTN,K-TIRADS2 AFTN,EU-TIRADS2,3 - - -

Pacemaker/Pregnantwomen

Monopolar:NoBipolar:Applicable

-Monopolar(notgood),Bipolar:applicable

- -

GuidelinebyKSThR:What?Indications Contraindications

1. Patientswithbenignthyroidnodulesproducingsymptomsorcosmeticconcerns

2.Autonomousfunctioningthyroidnoduleseithertoxicorpre-toxic

1.FollicularneoplasmormalignancyonFNAorCNB

2.AnodulewithUScriteriasuggestingmalignancy,despiteFNAorCNBresults

PotentialIndications RelativeContraindications

1. Primarythyroidcancerinpatientswhorefusesurgeryorareunsuitableforsurgery

2. Recurrentthyroidcancerinthethyroidectomybedandincervicallymphnodesinpatientsathighsurgicalriskorwhorefusesurgery

1. Pregnantwoman2. Severeheartdiseaseorpacemaker

*Bipolarprobe3. Existingvocalcordpalsyonthecontralateral

side

Pre-procedureWork-up(I)

Pre-procedureWork-up(II)

AblationStrategy:Compositionofthyroidnodules

RF ablationEthanol ablation

0% 10% 50% 100%

Combination TherapyEthanol ablation/RF ablation

Cystic Solid

Baek et al. Korean J Radiol 2015

Procedure

• Out-patient procedure

- 20-30 mins per nodule

(volume dependent)

• Local Anesthesia only

- Perithyroidal lidocaine injection

: IV conscious sedation : rarely

• Two Key Techniques

- Trans-isthmic approach

- Moving Shot

• Post-procedure observation

- 1 hours

PainControl:CanweavoidIVconscious(moderate)sedation?

• PerithyroidalLidocaineInjection

Thyroid Radiofrequency Ablation: Updates on Innovative Devices and Techniques.Park et al. Korean J Radiol. 2017

KeyTechniques(I):Trans-IsthmicApproach

Thermal Ablation for Benign Thyroid Nodules: Radiofrequency and Laser.Jung Hwan Baek et al. Korean journal of radiology 2011

KeyTechniques(II):MovingShot• Hepatictumor:round

RF needle fixed over several minutes.

KeyTechniques(II):MovingShot

• Thyroidnodule:elliptical

KeyTechniques(II):MovingShot

Danger triangleVagus N

RLN

ClinicalFollow-up

• USscan:theprimarytool

- Vascularityloss

:contrastenhancedUS(CEUS)

- Volumereduction(VR)

:VR(%)=[Initialvolume(ml)- Finalvolume(ml)]

x100/Initialvolume

• Labs

- TSH/FreeT4/T3

• Clinicalevaluation

- Symptomsandcosmeticproblems

ClinicalEfficacy:Non-FunctioningBenignNodules

Recurrence rate: 5.6%

RFA of Benign Non-functioning Thyroid Nodules : 4-Year Follow-up Results in 111 Patients. Lim and Baek et al. Eur Radiol 2012

• Volume reduction (%) = ([initial

volume (mL) -final volume (mL)]

x 100)/initial volume (mL)

• Therapeutic success rate

- volume reduction > 50%

• Mean volume reduction

rate(VRR)

- 80% in a systemic review

- Greater in cystic nodules than

in solid nodules

JCEM 2 March 2019

Baek et al. Radiology 2012 Jan;262(1):335-342

Is Thyroid RFA Safe?

§ 48 Complications in 1459 patients : 3.3%

§ Major complication rate: 1.4%

Complications: Multicenter study

Hematoma

31%

Voice change

31%

Vomiting

19%

Skin burn

8%

Tumor rupture

6%

Hypothyroidism

2%

Brachial plexus

injury 2%

Baek et al. Radiology 2012 Jan;262(1):335-342

Complications Number Incidence (%) Follow-up results Detection Recovery

Voice change 15 1.0recovered (13)

FU loss (2)1-2 1-90

Hematoma 15 1.0 recovered 1 <30

Vomiting 9 0.6 recovered 1-2 1-2Skin burn 4 0.3 recovered 1 <7

Brachial plexus injury 1 0.07 recovered 1 60

Nodule rupture 2 0.14 recovered 22-30 <30Abscess formation

with nodule rupture1 0.07 Surgery 50 -

Hypothyroidism 1 0.07 Medication 180 -

• FromJune2002toSeptember2009,1459patients,1543nodules,2197sessions

13institutions:RFtrainingcoursebyKSThR

Baek et al. Radiology 2012 Jan;262(1):335-342

Safety:ComplicationsfromAMulticenterStudy

• 48Complications:3.3%/patients/Majorcomplicationrate:1.4%

1. Cervical/Brachial plexus

2. Vagus nerve

3-1. Recurrent laryngeal nerve

3-2. Non-recurrent laryngeal nerve

4. Phrenic nerve

5. Spinal accessory nerve

6. Cervical sympathetic ganglion

Ha and Baek et al. RSNA 2012 as an education exhibit

Neck nerve anatomy Hydrodissection

Chilled D5W

ClinicalEfficacy:AutonomousFunctioningBenignNodules

• Cesareo etal.inEndocrineandMetabolicDisorders2019- Asystemicreviewandmeta-analysis

- 205nodulesin8articlespublishedbetween2008and2018

• Cerville etal.inClinEndocrinol2019

ClinicalEfficacy(II):AutonomousFunctioningBenignNodules

Conclusion• ThyroidRFAinBenignThyroidNodules

- Effective&Safe

:Alternativetosurgery

www.thyroidablationschool.com

TrainingCourse

TrainingCourse