Ultrasound-guided laser thermal ablation in the treatment of autonomous hyperfunctioning thyroid nodules and compressive nontoxic nodular goiter

Laser ablation and 131-iodine: a 24-month pilot study of combined treatment for large toxic nodular goiter

CONTEXT

It is normally recognized that the preferred treatment in large toxic thyroid nodules should be thyroidectomy.

OBJECTIVE

The aim of the study was to assess the efficacy of combined laser ablation treatment (LAT) and radioiodine 131 (131I) treatment of large thyroid toxic nodules with respect to rapidity of control of local symptoms, of hyperthyroidism, and of reduction of administered 131I activity in patients at refusal or with contraindications to surgery.

DESIGN AND SETTING

We conducted a pilot study at a single center specializing in thyroid care.

PATIENTS

Fifteen patients were treated with LAT, followed by 131I (group A), and a series of matched consecutive patients were treated by 131I only (group B).

INTERVENTION(S)

Laser energy was delivered with an output power of 3 W (1800 J per fiber per treatment) through two 75-mm, 21-gauge spinal needles. Radioiodine activity was calculated to deliver 200 Gy to the hyperfunctioning nodule.

MAIN OUTCOME MEASURE(S)

Thyroid function, thyroid peroxidase antibody, thyroglobulin antibody, ultrasound, and local symptoms were measured at baseline and up to 24 months.

RESULTS

Nodule volume reduction at 24 months was: 71.3 ± 13.4 vs 47.4 ± 5.5%, group A (LAT+131I) vs group B (131I), respectively; P < .001). In group A (LAT+131I), a reduction in radioiodine-administered activity was obtained (-21.1 ± 8.1%). Local symptom score demonstrated a more rapid reduction in group A (LAT+131I). In three cases, no 131I treatment was needed after LAT.

CONCLUSIONS

In this pilot study, combined LAT/131I treatment induced faster and greater improvement of local and systemic symptoms compared to 131I only. This approach seems a possible alternative to thyroidectomy in patients at refusal of surgery.

Diagnosis of endocrine disease: thyroid ultrasound (US) and US-assisted procedures: from the shadows into an array of applications

In patients with thyroid nodules, ultrasound (US) imaging represents an indispensable tool for assessment of the risk of malignancy. Over approximately four decades, innovative technology and successive improvements have facilitated its entry into the routine management and greatly improved its predictive value. When US features cannot reliably rule out thyroid cancer, US guidance allows a correct and safe sampling also of small or deeply located thyroid lesions. Obtained in this way, cytological or microhistological specimens may reliably define the nature of most thyroid nodules, and the information from histochemical or molecular markers shows promise in the classification of the remaining indeterminate cases. While a prompt surgical treatment can be offered in the minority of suspicious or definitely malignant cases, most individuals warrant only a follow-up. However, at initial evaluation, or over the years, a fraction of these benign lesions may grow and/or become symptomatic. Such cases may benefit from US-guided minimally invasive procedures as an alternative to surgery. Image-guided percutaneous treatments most often achieve relief of neck complaints, are inexpensive, and can be performed on an outpatient basis. The risk of major complications, after adequate training, is very low. Importantly, thyroid function is preserved. Currently, percutaneous ethanol injection for cystic lesions and thermal ablation, with laser or radiofrequency, for solid nodules are increasingly used and disseminated beyond the initial core facilities. In centres with expertise and high patient volume, their use should be considered as first-line treatment alternatives to surgery for selected patients with benign enlarging or symptomatic thyroid lesions.

Thyroid nodules treated with percutaneous radiofrequency thermal ablation: a comparative study

PURPOSE

Percutaneous radiofrequency thermal ablation (RTA) was reported as an effective tool for the management of thyroid nodules (TNs). The aim of this study was to investigate the effects of RTA and to establish whether they were treatment-related by comparison with a matched, untreated control group.

PATIENTS AND METHODS

The study population included 40 patients with compressive TNs: 22 had nontoxic TNs, and 18 had toxic TNs and were treated with methimazole. In all patients, a fine-needle aspiration cytology was performed to exclude a thyroid malignancy.

STUDY DESIGN

Twenty patients were treated with RTA (group A), and 20 others did not receive any treatment (group B). At baseline, age, gender, and TN features did not differ significantly between groups. All patients were clinically, biochemically, and morphologically evaluated at baseline and after 1, 3, 6, and 12 months.

RESULTS

TN volume significantly decreased in group A (1.8 ± 0.3 ml at 12 months vs. 13.3 ± 1.8 ml at baseline; P < 0.0001) and remained stable in group B [11.7 ± 1.5 ml at 12 months vs. 11.2 ± 1.5 ml at baseline; P = not significant (NS)]. At 3-, 6-, and 12-month evaluations, TN volume was significantly lower in group A than in group B (P < 0.005). At the end of the follow-up, pressure symptoms were improved in all patients in group A but persisted unchanged in group B. In group A, hyperthyroidism completely recovered in 40% and improved in 40% of patients with toxic TNs, whereas it persisted in all patients with toxic TNs in group B. RTA was safe and well tolerated in all patients.

CONCLUSIONS

RTA induced a marked TN volume shrinkage resulting in parallel improvement of pressure symptoms. In most patients with toxic TNs, hyperthyroidism significantly improved as well. RTA may represent a valid therapeutic approach in patients with TNs not receiving conventional treatments.

Radiofrequency ablation of benign non-functioning thyroid nodules: 4-year follow-up results for 111 patients

OBJECTIVES

To evaluate the clinical outcomes and safety of radiofrequency (RF) ablation for benign non-functioning thyroid nodules over a 4-year follow-up.

METHODS

We evaluated 126 benign non-functioning thyroid nodules of 111 patients treated with RF ablation and followed-up more than 3 years. RF ablation was performed using the Cool-Tip RF system and an internally cooled electrode. Nodule volume and cosmetic and symptom scores were evaluated before treatment and during follow-up. Complications and factors related to efficacy were evaluated.

RESULTS

The mean follow-up duration was 49.4 ± 13.6 months. Thyroid nodule volume decreased significantly, from 9.8 ± 8.5 ml before ablation to 0.9 ± 3.3 ml (P < 0.001) at final evaluation: a mean volume reduction of 93.4 ± 11.7 %. The mean cosmetic (P < 0.001) and symptom scores (P < 0.001) improved significantly. Factors related to efficacy were initial solidity and volume. The overall recurrence rate was 5.6 % (7/126). The overall complication rate was 3.6 % (4/111).

CONCLUSIONS

RF ablation was effective in shrinking benign thyroid nodules and in controlling nodule-related problems over a 4-year follow-up. There were no life-threatening complications or sequelae. Therefore, RF ablation can be used as a non-surgical treatment for patients with benign non-functioning thyroid nodules.

Ultrasound-guided interstitial laser ablation for thyroid nodules is effective only at high total amounts of energy: results from a three-year pilot study

OBJECTIVE

According to cross-sectional surveys, the prevalence of nontoxic nodular goiter appears to be higher in the adult population. Surgical intervention is indicated for the following: (a) progressive goiter growth, (b) compression of organs such as the trachea and esophagus, and (c) significant aesthetic disfigurement. Ultrasound-guided laser photocoagulation for the treatment of benign thyroid nodules is a viable alternative to traditional surgery. However, studies that have appeared in literature since the introduction of ultrasound-guided laser photocoagulation for the treatment of benign thyroid nodules report contradictory data concerning the energy required for nodule ablation. The aim of the present trial was to evaluate retrospectively the efficacy of percutaneous laser thermal ablation in 2 groups of patients, one treated with low, and the other with high, total amount of energy.

DESIGN

Forty euthyroid patients were treated with 1 session of percutaneous laser photocoagulation treatment at low (median = 71 J/mL; 20 patients) and high (median = 578 J/mL; 20 patients) energy. The volume of the nodules was measured by the same investigator, blinded for treatment, using the ellipsoid formula before treatment, at 2, 4, 8, and 30 weeks, and every 6 months for 3 years thereafter.

RESULTS

Thyroid nodule ablation is effective over time only if a sufficient amount of energy (>400-500 J/mL for the nodular tissue to be treated) is given, although it incurs proportionate side effects.

CONCLUSIONS

Percutaneous laser thermal ablation is a viable alternative to traditional surgery for the treatment of benign nodular thyroid disease only if a sufficient amount of energy is delivered.

Pathological findings of thyroid nodules after percutaneous laser ablation : a series of 22 cases with cyto-histological correlation

Ultrasound (US)-guided percutaneous laser ablation (LA) of benign thyroid nodules may be a potential alternative to surgery in patients with compressive symptoms, at high surgical risk, or in patients who refuse to undergo surgery. We evaluated the morphological effects of LA procedure on 22 patients and compared the cytological findings before and after LA with the histological features on surgical specimens. Twenty-two (4.9%; 19 women, three men, mean age 53.2 years) out of 452 patients treated with LA for benign thyroid nodules in our Hospital underwent surgery after LA procedure, either because nodule regrowth (treatment failure, n = 17) or indeterminate cytology (Thy3) after LA (n = 5). Morphological findings varied according to the time between LA and surgical intervention. Within 2 months, the area was occasionally cavitated and filled in with dark amorphous material. The inflammatory response was abundant and composed of neutrophils, lymphocytes, and macrophages. After 18 months or more since LA, the expected laser-induced histologic changes in thyroid morphology consisted of a well-defined area surrounded by a fibrous capsule and filled in by amorphous material. No significant pathologic features were found in the thyroid tissue adjacent to the treated area. Histological evaluation of thyroid tissues after LA shows that thermal damage is restricted to the ablated area, with no involvement of the nearby parenchyma. Our long-term histopathological findings indicate that LA treatment of benign thyroid nodules is safe, and patients undergoing LA may also be followed up by fine needle aspiration.

Ultrasound-guided percutaneous microwave ablation of benign thyroid nodules: experimental and clinical studies

PURPOSE

To obtain the treatment parameters of internally cooled microwave antenna and to evaluate the feasibility of ultrasound-guided percutaneous microwave ablation (MWA) for benign thyroid nodules.

MATERIALS AND METHODS

MWAs were performed by microwave antenna (16G) in ex vivo porcine liver. The lesion diameters achieved in different groups (20, 25, and 30 W for 3, 5, 7, 10, and 12 min) were compared. The clinical study was approved by the ethics committee. Written informed consent was obtained from all patients. MWA was performed in 11 patients (male to female ratio=1:10; mean age, 50±7 years) with 11 benign thyroid nodules. Ultrasound scan, laboratory data, and clinical symptoms were evaluated before and 1 day and 1, 3, 6, 9, and 12 months after the procedure.

RESULTS

In ex vivo study, the ablation lesion at 30 W 12 min tended to have appropriate scope and spherical shape. In clinical study, the follow-up periods ranged from 1 to 9 months. At the last follow-up, the largest diameter decreased from 2.9±1.0 (range, 1.6-4.1) to 1.9±0.7 (range, 0.4-3.0) cm (P<0.01), and the volume decreased from 5.30±4.88 (range, 0.89-14.81) to 2.40±2.06 (range, 0.02-6.35) ml (P<0.01). The volume reduction ratio was 45.99±29.90 (range, 10.56-98.15) %. The cosmetic grading score was reduced from 3.20±0.79 to 2.30±0.95 (P<0.05). One patient experienced temporary nerve palsy and was recovered within 2 months after treatment.

CONCLUSION

The internally cooled microwave antenna can yield ideal ablation lesions, and ultrasound-guided percutaneous MWA is a feasible technique for benign thyroid nodules.

Radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: consensus statement and recommendations

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus.

Tracheal laceration after laser ablation of nodular goitre

A tracheal perforation was discovered after Nd-YAG laser thermal ablation (LTA) of a thyroid nodule. The LTA is a relatively new method of treatment of thyroid nodules, which consists of delivering laser energy into the thyroid by means of two optical fibres. The patient presented with a multinodular goitre and initially refused surgery, then underwent an LTA of a thyroid nodule. Fifty days after the procedure she started to have symptoms related to a tracheal stenosis and, after tracheoscopy, a tracheal perforation was diagnosed and she underwent a total thyroidectomy plus tracheal repair. The results of the histological examination revealed a goitre with a focal area of papillary carcinoma. This particular complication is likely the first of its kind to be described after the LTA of a thyroid nodule.

The efficacy and complications of radiofrequency ablation of thyroid nodules

PURPOSE OF REVIEW

The use of radiofrequency ablation has increased rapidly in recent years and is receiving increased attention as a minimally invasive method to treat benign and malignant thyroid nodules.

RECENT FINDINGS

Radiofrequency ablation has been shown to be an alternative to surgery in the treatment of benign thyroid nodules. Radiofrequency ablation of benign cold nodules showed volume reductions of 32.7-58.2% at 1 month and 50.7-84.8% at 6 months, while reducing symptoms and cosmetic problems. Radiofrequency ablation of autonomously functioning thyroid nodules effectively improves thyroid function and reduces nodule volume. Recently, radiofrequency ablation of recurrent thyroid cancers showed good short-term results for locoregional control of well differentiated thyroid carcinoma in patients at high risk for surgery. Various complications of radiofrequency ablation have been reported, including pain, voice change, hematoma, skin burn at the puncture site, thyrotoxicosis, hypothyroidism, edema, and fever, but most patients recovered spontaneously without sequelae.

SUMMARY

Radiofrequency ablation is an effective and well tolerated treatment option for benign thyroid nodules. Radiofrequency ablation of recurrent thyroid cancers may be an alternative to surgery in patients at high surgical risk.

Thermal ablation for benign thyroid nodules: radiofrequency and laser

Although ethanol ablation has been successfully used to treat cystic thyroid nodules, this procedure is less effective when the thyroid nodules are solid. Radiofrequency (RF) ablation, a newer procedure used to treat malignant liver tumors, has been valuable in the treatment of benign thyroid nodules regardless of the extent of the solid component. This article reviews the basic physics, techniques, applications, results, and complications of thyroid RF ablation, in comparison to laser ablation.

Effectiveness of various thermal ablation techniques for the treatment of nodular thyroid disease--comparison of laser-induced thermotherapy and bipolar radiofrequency ablation

Alternative minimally invasive treatment options such as radiofrequency ablation (RFA) or laser-induced thermotherapy (LITT) are at present under investigation for achieving a nonsurgical targeted cytoreduction in benign and malignant thyroid lesions. So far, studies have not been able to show a secure advantage for neither LITT nor RFA. The aim of this study was to compare the two ablation procedures in terms of their effectiveness. Thermal lesions were induced in porcine thyroid glands either by LITT or bipolar RFA ex vivo (n = 110 each) and in vivo (n = 10 each) using power settings between 10 and 20 W. Temperature spread during application was documented in 5- and 10-mm distance of the applicator. Postinterventional lesion diameters were measured and lesion size was calculated. Furthermore, enzyme histochemical analysis of the thyroid tissue was performed in vivo. Lesion volumes induced by LITT ranged between 0.74 ± 0.18 cm(3) (10 W) and 3.80 ± 0.41 cm(3) (20 W) with a maximum of 5.13 ± 0.16 cm(3) at 18 W. The inducible lesion volumes by RFA were between 2.43 ± 0.68 cm(3) (10 W) and 0.91 ± 0.71 cm(3) (20 W) with a maximum of 2.80 ± 0.85 cm(3) at 14 W. The maximum temperatures were 112.9 ± 9.2°C (LITT) and 61.6 ± 13.9°C (RFA) at a distance of 5 mm and 73.2 ± 6.7°C (LITT) and 53.5 ± 8.6°C (RFA) at a distance of 10 mm. The histochemical analysis demonstrates a complete loss of NADPH dehydrogenase activity in thermal lesions as a sign of irreversible cell damage both for LITT and RFA. This study is the first to compare the effectiveness of laser-induced thermotherapy and radiofrequency ablation of thyroid tissue. LITT as well as RFA are suitable for singular thyroid nodules and induces reproducible clinically relevant lesions in an appropriate application time. The maximum inducible lesion volumes by LITT are significantly larger than by RFA with the devices used herein.

Percutaneous laser ablation of cold benign thyroid nodules: a 3-year follow-up study in 122 patients

BACKGROUND

Percutaneous laser ablation (PLA) is a proposed therapeutic procedure for the management of benign thyroid nodules. However, long-term results are unknown. The aim of this study was to evaluate retrospectively the safety and effects of PLA treatment in patients with benign nonfunctioning thyroid nodules in a 3-year follow-up.

METHODS

One hundred twenty-two patients (95 women and 27 men; age 52.2 ± 12.3 years) with benign cold thyroid solitary nodules or a dominant nodule within a normo-functioning multinodular goiter (volume range: 2.6-86.4 mL) underwent thermal Nd:YAG laser ablation of thyroid nodular tissue by 1-4 optical fibers positioned into the tissue by 21-gauge needles under ultrasound real-time assistance. The setting was an interventional suite and outpatient endocrine clinics in a community hospital in Italy. Nodule volume, ablation volume, side effects, serum thyroid-stimulating hormone (TSH), free triiodothyronine, free thyroxine (fT4), thyroglobulin (Tg), anti-Tg, anti-thyroperoxidase antibodies, symptoms, and cosmetic signs were recorded.

RESULTS

Data are mean ± standard deviation. Energy delivered was 8522  ± 5365 J with an output power of 3.1 ± 0.5 W. Three years after PLA, nodule volume decreased from 23.1 ± 21.3 to 12.5 ± 18.8 mL (-47.8%  ± 33.1% of initial volume, p ≤ 0.001). At day 1, TSH and fT4 values significantly changed (time 0 vs. day 1: TSH = 1.16  ± 1.06 vs. 0.62 ± 0.81 μU/mL, p ≤ 0.001; fT4 = 11.68 ± 1.88 vs. 13.20 ± 3.32 pg/mL, p ≤ 0.01) and normalized within 1 month. No change in free triiodothyronine, thyroperoxidase antibodies, and Tg antibodies values was observed. Symptoms improved in 89 patients (73.0%), were unchanged in 28 (22.9%), and worsened in 5 (4.1%). Cosmetic signs improved in 87 patients (71.3%), were unchanged in 29 (23.8%), and worsened in 6 (4.9%). In 11 patients (9%), nodules regrew above baseline. Two patients (1.6%) experienced delayed (12-24 hours) laryngeal dysfunction with vocal cord motility recovery after 6-10 weeks. Two patients (1.6%) became hypothyroid and two patients (1.6%) hyperthyroid after PLA.

CONCLUSIONS

After 3 years, the PLA technique achieved shrinkage of about 50% of the initial volume in a wide size range of benign cold thyroid nodules, with an improvement in local symptoms and signs. Side effects and failures were few although not negligible. PLA may be a new option for the management of benign cold thyroid nodules. Long-term controlled studies are required to establish the eligibility of patients for routine PLA.

Benign predominantly solid thyroid nodules: prospective study of efficacy of sonographically guided radiofrequency ablation versus control condition

OBJECTIVE

The purpose of this study was to evaluate the efficacy of radiofrequency ablation of benign predominantly solid thyroid nodules by comparing the findings in treatment and control groups.

SUBJECTS AND METHODS

Thirty patients with normal thyroid function, each with a benign predominantly (> 50%) solid thyroid nodule causing pressure symptoms or cosmetic problems, were assigned to a control group (n = 15) or to a group undergoing a single session of radiofrequency ablation (n = 15). Thyroid nodule volume, thyroid function, pressure symptoms, and cosmetic concerns were evaluated before treatment and during follow-up. Sonographically guided radiofrequency ablation was performed with an internally cooled electrode (1-cm active tip) with an output power of 30-80 W.

RESULTS

The control group had no resolution of symptoms or cosmetic problems. The mean nodule volume increased slightly after 6 months but without statistical significance (p = 0.46). In the radiofrequency ablation group, the mean symptom score (p = 0.001) and cosmetic grade (p = 0.001) improved significantly. Mean nodule volume decreased significantly from 7.5 +/- 4.9 mL (range, 1.7-20.0 mL) to 1.3 +/- 0.8 mL (range, 0.2-2.6 mL) 6 months after radiofrequency ablation (p = 0.001). There were no major complications of ablation.

CONCLUSION

This study confirmed that radiofrequency ablation is effective for reducing nodule volume and relieving nodule-related clinical problems and that an effect due to spontaneous nodule reduction can be excluded owing to the results of the comparison with a similar control group.

Ex vivo and in vivo evaluation of laser-induced thermotherapy for nodular thyroid disease

BACKGROUND AND OBJECTIVE

The prevalence of thyroid nodules ranges between 2% and 60% depending on the population studied. However, minimally invasive procedures like laser-induced thermotherapy (LITT) are increasingly used to treat tumors of parenchymatous organs and seem to be suitable for singular thyroid nodules as well. Their successful clinical application depends on the induction of sufficiently large lesions and a knowledge of the energy parameters required for complete thermal ablation. The aim of this study was to establish a dose-response relationship for LITT of thyroid nodules.

MATERIALS AND METHODS

Thermal lesions were induced in healthy porcine thyroid glands ex vivo (n = 110) and in vivo (n = 10) using an Nd:YAG laser (1,064 nm). Laser energy was applied for 300 seconds in a power range of 10-20 W. During the ablation, continuous temperature measurement at a distance of 5 and 10 mm from the applicator was performed. The lesions were longitudinally and transversally measured, and the volume was calculated. Furthermore, enzyme histochemical analysis of the thyroid tissue was performed.

RESULTS

The maximum inducible lesion volumes were between 0.74 +/- 0.18 cm(3) at a laser power of 10 W and 3.80 +/- 0.41 cm(3) at 20 W. The maximum temperatures after ablation were between 72.9 +/- 2.9 degrees C (10 W) and 112.9 +/- 9.2 degrees C (20 W) at a distance of 5 mm and between 49.5 +/- 2.2 degrees C (10 W) and 73.2 +/- 6.7 degrees C (20 W) at a distance of 10 mm from the applicator. The histochemical analysis demonstrates a complete loss of NADPH dehydrogenase activity in thermal lesions as a sign of irreversible cell damage.

CONCLUSIONS

This study is the first to demonstrate a dose-response relationship for LITT of thyroid tissue. LITT is suitable for singular thyroid nodules and induces reproducible clinically relevant lesions with irreversible cell damage in an appropriate application time.

Bipolar radiofrequency ablation for nodular thyroid disease--ex vivo and in vivo evaluation of a dose-response relationship

BACKGROUND

The prevalence of thyroid nodules ranges between 2% and 60% depending on the population studied. However, minimally invasive procedures like radiofrequency ablation (rfA) are increasingly used to treat tumors of parenchymatous organs, and seem to be suitable for singular thyroid nodules as well. Their successful clinical application depends on the induction of sufficiently large lesions and a knowledge of the energy parameters required for complete thermal ablation. The aim of this study was to establish a dose-response relationship for rfA of thyroid nodules.

MATERIAL AND METHODS

Thermal lesions were induced in healthy porcine thyroid glands ex vivo (n=110) and in vivo (n=10) using a bipolar radiofrequency system; rf was applied in a power range of 10-20 watts. During the ablation, continuous temperature measurement at a distance of 5 and 10 mm from the applicator was performed. The transversal and axial lesion diameters were measured, and the volume was calculated. Furthermore, enzyme histochemical analysis of the thyroid tissue was performed.

RESULTS

The inducible lesion volumes were between 0.91±0.71 cm(3) at 20W and 2.80±0.85 cm(3) at 14W. The maximum temperatures after rf ablation were between 44.0±9.7°C and 61.6±13.9°C at a distance of 5 mm and between 30.0±8.6°C and 53.5±8.6°C at a distance of 10 mm from the applicator. The histochemical analysis demonstrates a complete loss of nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) dehydrogenase activity in thermal lesions as a sign of irreversible cell damage.

CONCLUSION

This study is the first to demonstrate a dose-response relationship for rfA of thyroid tissue. rfA is suitable for singular thyroid nodules and induces reproducible, clinically relevant lesions with irreversible cell damage in an appropriate application time.

Thyroid nodules and related symptoms are stably controlled two years after radiofrequency thermal ablation

BACKGROUND

Percutaneous radiofrequency thermal ablation (RTA) is a promising new therapeutic approach to manage thyroid nodules (TNs). The aim of this study was to investigate the long-term effectiveness of RTA in inducing shrinkage of TNs as well as in controlling compressive symptoms and thyroid hyperfunction in a large series of elderly subjects with solid or mainly solid benign TNs.

METHODS

Ninety-four elderly patients with cytologically benign compressive TNs were prospectively enrolled in the study; 66 of them had nontoxic goiter and 28 had toxic or pretoxic goiter. RTA was performed by using a RITA StarBurst Talon hook-umbrella needle inserted in every single TN under ultrasonographic real-time guidance. TN volume, TN-related compressive symptoms and thyroid function were evaluated at baseline and 12 to 24 months after RTA.

RESULTS

All TNs significantly decreased in size after RTA. The mean decrease in TN volume 12 months after RTA was from 24.5 +/- 2.1 to 7.5 +/- 1.2 mL (p < 0.001), with a mean percent decrease of 78.6 +/- 2.0%. Two years after RTA, a 79.4 +/- 2.5% decrease of TNs size was observed. Compressive symptoms improved in all patients and completely disappeared in 83 of 94 (88%) patients. Hyperthyroidism resolved in most patients allowing methimazole therapy to be completely withdrawn in 79% of patients with pretoxic and toxic TNs (100% with pretoxic TNs and 53% with toxic TNs). The treatment was well tolerated by all patients. No patient needed hospitalization after RTA and no major complications were observed.

CONCLUSIONS

RTA is an effective and simple procedure for obtaining lasting shrinkage of TNs, controlling compressive symptoms, and treating thyroid hyperfunction. When performed in experienced medical centers, RTA may be a valid alternative to conventional treatments for nontoxic and pretoxic TNs. It is particularly attractive for elderly people for whom surgery and radioiodine therapy are often contraindicated or ineffective.

Percutaneous laser ablation of benign and malignant thyroid nodules

PURPOSE OF REVIEW

Percutaneous image-guided procedures, largely based on thermal ablation, are at present under investigation for achieving a nonsurgical targeted cytoreduction in benign and malignant thyroid lesions.

RECENT FINDINGS

In several uncontrolled clinical trials and in two randomized clinical trials, laser ablation has demonstrated a good efficacy and safety for the shrinkage of benign cold thyroid nodules. In hyperfunctioning nodules, laser ablation induced a nearly 50% volume reduction with a variable frequency of normalization of thyroid-stimulating hormone levels. Laser ablation has been tested for the palliative treatment of poorly differentiated thyroid carcinomas, local recurrences or distant metastases.

SUMMARY

Laser ablation therapy is indicated for the shrinkage of benign cold nodules in patients with local pressure symptoms who are at high surgical risk. The treatment should be performed only by well trained operators and after a careful cytological evaluation. Laser ablation does not seem to be consistently effective in the long-term control of hyperfunctioning thyroid nodules and is not an alternative treatment to 131I therapy. Laser ablation may be considered for the cytoreduction of tumor tissue prior to external radiation therapy or chemotherapy of local or distant recurrences of thyroid malignancy that are not amenable to surgical or radioiodine treatment.

US-guided percutaneous radiofrequency thermal ablation for the treatment of solid benign hyperfunctioning or compressive thyroid nodules

The aim of the study was to define the effectiveness and safety of ultrasound-guided percutaneous radiofrequency (RF) thermal ablation in the treatment of compressive solid benign thyroid nodules. Thirty-one patients not eligible for surgery or radioiodine (131I) treatment underwent RF ablation for benign nodules; a total of 33 nodules were treated (2 patients had 2 nodules treated in the same session): 10 cold nodules and 23 hyperfunctioning. Fourteen patients complained of compressive symptoms. Nodule volume, thyroid function and compressive symptoms were evaluated before treatment and at 1, 3 and 6 mo. Ultrasound-guided RF ablation was performed using a Starbust RITA needle, with nine expandable prongs; total exposure time was 6 to 10 min at 95 degrees C in one area or more of the nodule. Baseline volume (measured at the time of RF ablation) was 27.7 +/- 21.5 mL (mean +/- SD), but significantly decreased during follow-up: 19.2 +/- 16.2 at 1 mo (-32.7%; p < 0.001), 15.9 +/- 14.1 mL at 3 mo (-46.4 %; p < 0.001) and 14.6 +/- 12.6 mL at 6 mo (-50.7%; p < 0.001). After treatment, all patients with cold nodules remained euthyroid: five patients with hot nodules normalized thyroid function, and the remaining sixteen showed a partial remission of hyperthyroidism. Besides a sensation of heat and mild swelling of the neck, no major complications were observed. Improvement in compressive symptoms was reported by 13 patients, with a reduction on severity scale from 6.1 +/- 1.4 to 2.2 +/- 1.9 (p < 0.0001). Radiofrequency was effective and safe in reducing volume by about 50% and compressive symptoms in large benign nodules. Hyperfunction was fully controlled in 24% of patients and partially reduced in the others.

Radiofrequency ablation of benign thyroid nodules: safety and imaging follow-up in 236 patients

This study evaluated the safety and volume reduction of ultrasonography (US)-guided radiofrequency ablation (RFA) for benign thyroid nodules, and the factors affecting the results obtained. A total of 302 benign thyroid nodules in 236 euthyroid patients underwent RFA between June 2002 and January 2005. RFA was carried out using an internally cooled electrode under local anesthesia. The volume-reduction ratio (VRR) was assessed by US and safety was determined by observing the complications during the follow-up period (1-41 months). The correlation between the VRR and several factors (patient age, volume and composition of the index nodule) was evaluated. The volume of index nodules was 0.11-95.61 ml (mean, 6.13 +/- 9.59 ml). After ablation, the volume of index nodules decreased to 0.00-26.07 ml (mean, 1.12 +/- 2.92 ml) and the VRR was 12.52-100% (mean, 84.11 +/- 14.93%) at the last follow-up. A VRR greater than 50% was observed in 91.06% of nodules, and 27.81% of index nodules disappeared. The complications encountered were pain, hematoma and transient voice changes. In conclusion, RFA is a safe modality effective at reducing volume in benign thyroid nodules.

Treatment of benign cold thyroid nodules: a randomized clinical trial of percutaneous laser ablation versus levothyroxine therapy or follow-up

AIM OF THE STUDY

To compare clinical and ultrasound (US) changes induced in cold thyroid nodules by US-guided percutaneous laser ablation (PLA) versus follow-up or levothyroxine (LT4) suppressive therapy.

METHODS

62 patients randomly assigned to a single PLA (Group 1), LT4 (Group 2), or follow-up (Group 3). Entry criteria: euthyroid patients with a solid thyroid nodule >5 mL and benign cytological findings.

TREATMENT

Group 1: PLA was performed with a 1.064 mum neodymium yttrium-aluminum-garnet laser with output power of 3 W for 10 minutes; Group 2: the LT4 dose was adjusted to induce thyrotropin suppression; Group 3: no treatment.

RESULTS

In Group 1 a significant nodule reduction was found 6 and 12 months after PLA (delta volume: -42.7 +/- 13.6%; p = 0.001). A reduction >50% was found in 33.3% of cases. In Group 2 a nonsignificant nodule shrinkage was observed. A nonsignificant volume increase was observed in Group 3. Improvement of local symptoms was registered in 81.2% of patients in Group 1 vs. 13.3% in Group 2 and 0.0% in Group 3 ( p = 0.001). No complications were noted.

CONCLUSIONS

A single PLA induced significant volume reduction and improvement of local symptoms. PLA was more effective than LT4. Follow-up was associated with nodule growth and progression of local symptoms. PLA should be considered a potential mini-invasive alternative to surgery in symptomatic patients with benign cold thyroid nodules.

Percutaneous Laser Ablation in the Treatment of Toxic and Pretoxic Nodular Goiter

OBJECTIVE

To report data regarding treatment with use of percutaneous laser ablation (PLA) in autonomously functioning thyroid nodules (AFTN).

METHODS

We treated 18 patients (10 women and 8 men, 31 to 80 years old) who presented with a single hyperfunctioning thyroid nodule (8 patients) or a multi-nodular goiter (10 patients) with clearly hyperfunctioning areas on a thyroid scintiscan. In 5 cases, free thyroxine (FT4) and free triiodothyronine (FT3) levels were high, and in these patients and a further 9 patients with cardiovascular symptoms, methimazole therapy was initiated to restore euthyroidism. The total number of PLA sessions ranged from 1 to 5 (median, 3). Thyroid-stimulating hormone, FT4, FT3, thyroglobulin, and antithyroglobulin and anti-thyroid peroxidase antibodies were measured by a commercial kit the day after PLA treatment, then weekly during the first month, and monthly thereafter. The Student t test was used for statistical analyses, and data are reported as mean values +/- SE.

RESULTS

After each PLA session, there was a transient and mild increase in FT4 and FT3-5.2% to 18.1% (mean, 11.1 +/- 0.69%) (P<0.001) in patients not treated with methimazole and 4.0% to 8.3% (mean, 5.9 +/- 0.31%) (P<0.001) in patients treated with methimazole-relative to values before treatment; however, these values never reached the range of hyperthyroidism. In addition, thyroglobulin showed a remarkable increase after 24 hours- 115% to 390% (mean, 266.0 +/- 12.7%) (P<0.001). Thyroid-stimulating hormone increased in all cases and reached normal values in all patients with single AFTN and in 5 patients (50%) with multinodular goiter within 3 months after PLA. At 1-year follow-up, the decrease in nodular volume was 24% to 72% (mean, 59.3 +/- 8.2%; P<0.001).

CONCLUSION

Our data show that PLA can be a useful treatment in AFTN and particularly in single toxic nodules. Possible elective indications are patients who refuse surgical or radioiodine treatment and patients with cardiovascular comorbidity who need rapid restoration of the euthyroid state and who cannot tolerate the discontinuation of antithyroid drugs for radioiodine treatment.

Effects of percutaneous laser ablation treatment in benign solitary thyroid nodules on nodule volume, thyroglobulin and anti-thyroglobulin levels, and cytopathology of nodule in 1 yr follow-up

OBJECTIVE

To investigate the effects of ultrasound (US)-guided percutaneous laser ablation (PLA) in the treatment of benign solid hypoactive thyroid nodules on nodule volume, thyroid functions, nodule cytology and patients' complaints.

MATERIAL AND METHOD

Criteria for enrollment in the study were as follows: patients with euthyroid, benign, hypofunctional nodule who had compressive symptoms or cosmetic complaints, but considered inoperable, or who rejected surgical treatment. PLA procedure at 3-5 watts (W) was applied to 15 thyroid nodules of 12 patients (4 male and 8 female; age range 20-78 yr, mean age 47.42+/-17.05 yr), and patients were followed up for 12 months. Thyroid functions and nodule volumes (ultrasonographically) were evaluated. US-guided fine needle aspiration biopsy (FNAB) was performed before and after the procedure, and biopsy specimens were cytologically evaluated.

RESULTS

The mean nodule volume before the procedure was 11.97 ml (min-max 0.95-26.30 ml). However, 12 months after the procedure the mean nodule volume was 2.21+/-2.32 ml (min-max 0.10-7.65 ml). The mean reduction in nodule volumes was 82%. Thyroglobulin levels reached peak values at 1 month after the procedure, and anti-thyroglobulin levels at 3 months after the procedure. FNAB performed at 12th month showed neutrophil polymorphs, macrophages, abundant cell debris, colloid, multinucleated giant cells, and small fragments of fibrous stroma which indicated that PLA procedure led to degenerative changes in nodules.

CONCLUSION

US-guided PLA is a new, successful treatment method which is reliable in the long term in benign solid thyroid nodules for selected patients who are inoperable or do not prefer surgery.

A randomized controlled trial to evaluate the efficacy of ultrasound-guided laser photocoagulation for treatment of benign thyroid nodules

This randomized controlled study was designed to test the efficacy and safety of percutaneous ultrasound (US)-guided laser photocoagulation (PLP) for treatment of subjects with compressive symptoms due to benign thyroid nodules and/or at high surgical risk. Twenty six subjects were randomized to the intervention (no. 13, age 68+/-3 yr, mean+/-SEM) or observation (no. 13, age 71+/-2 yr) groups. In the control group, the volume of nodules did not significantly change over the 30 week period of observation. In the intervention group, median nodule volume at baseline was 8.2 ml (range 2.8-26.9) and was not significantly different from that of the control group. Nodules decreased significantly (p<0.0001) by 22% after 2 weeks (6.5 ml; range 2.4-16.7) and by 44% after 30 weeks (4.6 ml; range 0.69-14.2). Energy given was correlated (p<0.05) with the reduction of thyroid nodule volume. All patients tolerated the treatment well and reported relief from compressive and cosmetic complaints (p<0.05). At the time of enrolment 7/13 (54%) and 6/13 (46%) of patients in the intervention and control groups, respectively, had sub clinical hyperthyroidism. PLP normalized thyroid function at 6 and 30 weeks after treatment. In conclusion, PLP is a promising safe and effective procedure for treatment of benign thyroid nodules in patients at high surgical risk.

Effect of ultrasound-guided interstitial laser photocoagulation on benign solitary solid cold thyroid nodules: one versus three treatments

OBJECTIVE

Interstitial laser photocoagulation (ILP) is a safe and effective procedure when inducing thyroid nodule necrosis. In this prospective randomized study, we evaluated a possible dose-response relationship as well as patient satisfaction.

DESIGN

Thirty euthyroid outpatients with a cytologically benign solitary solid and scintigraphically cold thyroid nodule causing local discomfort were assigned to one session of ILP (ILP-1) (n = 15) or three monthly ILP sessions (ILP-3) (n = 15) and followed for 6 months. ILP was performed under continuous ultrasound (US)--guidance and with an output power of 2.5-3.5 W. Thyroid nodule volume was assessed by US. Pressure and cosmetic complaints were evaluated on a visual analogue scale.

MAIN OUTCOME

In the ILP- 1 group, thyroid nodule volume decreased from 10.1 +/- 4.3 mL (mean +/- standard deviation [SD]) to 5.7 +/- 3.2 mL (p = 0.0004), and in the ILP-3 group from 10.8 +/- 5.5 mL to 4.6 +/- 3.0 mL (p = 0.0005) during follow-up. The overall mean difference between the two groups was 13%, corresponding to an improved mean thyroid nodule volume reduction of 30% (p = 0.03). In both groups subjective symptoms were significantly reduced, and without difference between the two groups (p = 0.7). No major side effects were seen in either group.

CONCLUSION

As a nonsurgical therapeutic option, ILP-1 approximately halves thyroid nodule volume with concomitant symptom relief. There is little incremental effect of additional ILP treatment, which should be limited to patients with large nodules or limited nodule reduction after the first treatment.

Low-energy interstitial laser photocoagulation for treatment of nonfunctioning thyroid nodules: therapeutic outcome in relation to pretreatment and treatment parameters

OBJECTIVE

Interstitial laser photocoagulation (ILP) is a recently proposed therapeutic procedure for the ablation of benign thyroid nodules, which has already proven to be safe and effective. However, results supporting the routine use of ILP are still limited.

DESIGN

The aim of the study was to evaluate the efficacy and safety of ILP treatment in benign nonfunctioning thyroid nodules and to establish whether the therapeutic outcome may be predicted by any clinical parameter at baseline. Twenty-three patients with either a solitary nodule or a dominant nodule within a multinodular goiter underwent ILP and were evaluated 1 and 3 months later. In order to assess the efficacy of low-energy ILP, the procedure was performed with an output power of 3 W, delivering a mean energy of 33.4 +/- 12.7 Joule/mL of nodule volume, which is much lower than previously reported.

MAIN OUTCOME

Nodule volume significantly decreased after ILP as assessed after 1 and 3 months (analysis of variance; F = 5.37; p = 0.007). Patients with multinodular goiter showed a greater reduction at 3 months compared with patients bearing a solitary thyroid nodule (38.6 +/- 5.3 vs. 30.9 +/- 6.5%; p < 0.01). Age, sex, ultrasound pattern (isoechogenous/hypoechogenous), pretreatment volume, number of ILP treatments, and total energy delivered did not show any significant correlation with treatment outcome.

CONCLUSIONS

Our results demonstrate that ILP can produce a significant reduction of thyroid nodule volume even when a much lower energy than previously reported is delivered. ILP constitutes a minimally invasive technique, which can be carried out on an outpatient basis and could represent a valid nonsurgical alternative for thyroid nodule management. Dominant nodules within a multinodular goiter appear to be more responsive to ILP compared with solitary thyroid nodules.

Beneficial effect of combined aspiration and interstitial laser therapy in patients with benign cystic thyroid nodules: a pilot study

The aim of this study was to evaluate the effect of combined cyst aspiration and ultrasound-guided interstitial laser photocoagulation (ILP) on recurrence rate and the volume of benign cystic thyroid nodules. 10 euthyroid outpatients with a solitary and cytologically benign partially cystic thyroid nodule causing local discomfort were assigned to cyst aspiration followed by ultrasound-guided ILP and followed for 12 months. The ILP was performed under continuous ultrasound-guidance and with an output power of 2.5-3.5 W. The volume of the nodules was assessed by means of ultrasound and determination of the amount of aspirated cyst fluid, thereby calculating the volume of the solid part. Follow-up included ultrasound and determination of thyroid function. Pressure and cosmetic complaints were evaluated on a visual analogue scale. The median initial volume of the cystic nodule decreased from 9.6 ml [6.8;15.5 (quartiles)] to 3.5 ml [2.7;9.0 (quartiles)] (p = 0.0001), and the median cyst volume from 3.0 ml [2.0;6.0 (quartiles)] to 0 ml [0;0.5 (quartiles)] (p = 0.0001) during follow-up. Recurrence of the cystic part was defined as a cyst volume > 1 ml. In eight of 10 patients there was no recurrence of the cystic part. Both pressure symptoms and cosmetic complaints were significantly reduced. The only side effect was mild pain or tenderness for a few days. Our study suggests that complete cyst aspiration and subsequent ultrasound-guided ILP of benign cystic thyroid nodules is a feasible and safe technique, resulting in a significant reduction in the volume of both the solid and the cystic component. A large-scale prospective randomized study is warranted.

Nonsurgical approaches to the management of thyroid nodules

Epidemiologic studies have documented substantial increases in the frequency of nodular thyroid disease. This trend is largely due to the increasing detection of nodules by the routine use of sonography in clinical practice. Only a small percentage of the nodules currently being detected will prove to be malignant. The probability of malignancy is similar in nonpalpable and palpable nodules. Fine-needle aspiration cytology has a central role in identifying malignant nodules, which are generally treated with surgery. Most thyroid nodules are cytologically benign and can be managed nonsurgically. Nodules that are completely asymptomatic require follow-up without treatment. Cosmetic problems and/or compression-related symptoms may be indications for surgery. When surgery is contraindicated or refused, several nonsurgical approaches are available. These include levothyroxine therapy, radioiodine treatment, percutaneous ethanol injections, and the new technique of laser photocoagulation. Levothyroxine therapy is the most widely used approach, but its clinical efficacy and safety are controversial. Levothyroxine might, nonetheless, be appropriate in selected cases characterized by low risk for adverse effects and nodule characteristics associated with response to this type of therapy. Radioiodine is the therapy of choice for toxic nodules or for symptomatic nodular goiters when surgery is not possible. Percutaneous ethanol injection should be used, in our opinion, as the first-line therapy only for recurrent symptomatic cystic nodules. Laser therapy should be reserved for selected patients treated in experienced centers only. With these options, clinicians can personalize the management of nodular thyroid disease according to a careful cost-benefit analysis.

Radiofrequency ablation of benign cold thyroid nodules: initial clinical experience

CONTEXT AND OBJECTIVE

To evaluate the efficacy and safety of ultrasound (US)-guided percutaneous radiofrequency (RF) ablation for benign cold thyroid nodules as a nonsurgical therapeutic modality. DESIGN, INTERVENTION, AND PATIENTS: A total of 35 benign cold thyroid nodules in 30 euthyroid patients (M:F = 2:28; mean age 39.1 years) underwent percutaneous RF ablation with a 1-cm-internally cooled electrode. Seventy-seven percent (23/30) of patients required conscious sedation for discomfort. We evaluated the tumor size, cystic component, vascularity (by color Doppler US), and the severity of mass-related symptoms before treatment. We assessed the therapeutic efficacy and safety of RF ablation by clinical and US follow-up (median 6.4 months).

MAIN OUTCOME AND RESULTS

The volume of the tumors before ablation had a range of 0.6-28.2 mL (mean, 6.3 mL). The residual volume was 53.5% +/- 26.5% of original at 1.1-2.9 months (n = 32), 36.2% +/- 27.4% at 3.0-5.9 months (n = 20), 30.7% +/- 25.0% at 6.0-8.9 months (n = 15), and 11.8% +/- 10.9% at 9.0-18.5 months (n = 13). Mixed/mainly cystic tumors showed a significantly better response than mainly solid tumors (p < 0.05). Difference in vascularity did not affect the treatment response. Thyroid function after the procedure was maintained as normal in all patients. Eighty-eight percent of the patients reported an improvement of their symptoms. There was no major complication other than vocal cord palsy in one patient (3.3%).

CONCLUSION

RF ablation may be an effective and safe nonsurgical technique to treat benign cold thyroid nodules.

Effect of ultrasound-guided interstitial laser photocoagulation on benign solitary solid cold thyroid nodules - a randomised study

AIM

To evaluate the efficacy of ultrasound (US)-guided interstitial laser photocoagulation (ILP) on thyroid function, nodule size and patient satisfaction in benign solitary solid cold thyroid nodules by comparing one ILP session with no treatment in a prospective randomised study.

MATERIALS AND METHODS

Thirty euthyroid outpatients with a benign solitary solid and a scintigraphically cold thyroid nodule causing local discomfort were assigned to one session of ILP (n = 15) or observation (n = 15) and followed for 6 months. Thyroid nodule volume and total thyroid volume were assessed by US and thyroid function was determined by routine assays before and during follow-up. Pressure and cosmetic complaints before and at 6 months were evaluated on a visual analogue scale. ILP was performed under US guidance and with an output power of 2.5-3.5 W.

RESULTS

In the ILP group, the nodule volume decreased from 8.2 ml (6.1; 11.9) (median; quartiles) to 4.8 ml (3.0; 6.6) after 6 months (P = 0.001). The overall median reduction was 44% (37; 52), which correlated with a significant decrease in pressure symptoms as well as cosmetic complaints. In the control group, a non-significant increase in median nodule volume of 7% (0; 34) after 6 months was seen. No major side-effects were seen in the ILP group. There was no correlation between thermal energy deposition and nodule volume reduction. Thyroid function was unaltered throughout.

CONCLUSION

US-guided ILP, given as a single treatment, resulted in a satisfactory clinical response in the majority of patients with a benign solitary solid cold thyroid nodule, and may become a clinically relevant alternative to surgery in selected patients.