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