Thyroid Adenomas is a very common cause of pressure symptoms, swallowing difficulties
and cosmetic symptoms. However, the majority of thyroid adenomas are benign, and do
not need treatment if they are asymptomatic. When treatment is required, the standard
treatment in most centers is surgery, typically in the form of a lobectomy (removal
of a thyroid lobe). In order to avoid the risks associated with surgery: bleeding,
infection, recurrent laryngeal nerve damage and postoperative hypothyroidism [1]
[2], radiofrequency ablation has been introduced as a minimally invasive treatment option.
Radiofrequency ablation (or RFA) is a technique in which radiofrequency energy (an
electric current) is used to generate heat that destroys the cells and causes the
adenoma to shrink.
Candidates for treatment with radiofrequency ablation are patients with a symptomatic
benign solitary hypofunctioning (cold) thyroid nodule, with a volume between 2 and
20 ml. Prior to treatment, two benign fine needle aspiration cytology samples must
be present, in order to be as sure as possible that the nodule to be treated is benign.
The expected average volume reduction of the treated adenoma is around 70 % after
one year [3], as well as improvement of discomfort from the adenoma can be expected [4].
The treatment takes place in an outpatient clinic setting. It is done under local
anesthesia and typically lasts 30 minutes. The technique is very similar to that used
in ultrasound-guided fine needle aspiration. A “trans-isthmic” approach is used to
avoid coming into contact with the recurrent laryngeal nerve. ([Fig. 1]). A setup is typically used where the attending physician sits at the head end of
the patient and thus has a good overview, and both hands are free to move ([Fig. 2]).
Fig. 1 Trans-isthmic technique with RFA electrode A: Danger triangle with Recurrent Laryngeal Nerve; B: Oesophagus; C: Vagal Nerve; D: Carotid Artery; E: Adenoma; F: Trachea.
Fig. 2 Setup in RFA treatment. RFA is done as a sterile procedure, and the physician is
at the head end, with the ultrasound in one hand and the RFA electrode in the other
hand.
The radiofrequency ablation technique was developed in South Korea and has spread
to several European countries in recent years, and is also recommended by the European
Thyroid Society, ETA [5]. Copenhagen University Hospital – Rigshospitalet (CUH-RH) is the first center in
the Nordic Countries to offer treatment of thyroid adenomas with radiofrequency ablation.
Over the past two and a half years, more than 80 patients have been treated at the
department of otolaryngology at CUH-RH. Patients are offered inclusion in a study
of self-reported thyroid related quality of life using the THYPRO questionnaire. Measurements
are done before treatment and 3 months and 1 year after the treatment.
For further information or a visit to see RFA treatment being carried out at our department,
the authors can be contacted (mikkel.kaltoft.01@regionh.dk).
Advantages of RFA
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Less invasive procedure than surgery.
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No need for full anesthesia.
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Performed in an outpatient setting.
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Shorter recovery time than after surgery.
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No surgical scar.
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Low rate of complications.
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Preservation of thyroid function and less risk of hypothyroidism.
Disadvantages of RFA
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No histological diagnosis is made as in surgery.
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Serious complications are rare. The most frequent risks are pain, bleeding, burns
to the skin and infection. Infection can be a delayed problem and manifest itself
with swelling, pain and redness.
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Rare serious complications include damage to the oesophagus, trachea and recurrent
laryngeal nerve. The risk of permanent damage to the vocal cord nerve leading to a
change in voice is less than 1 %.
Mikkel Kaltoft, Tobias Todsen & Christoffer Holst Hahn
Department of Otorhinolaryngology, Head and Neck Surgery & Audiology – Rigshospitalet,
Copenhagen, Denmark
