Correction to letter: Image­guided thermal ablation of benign thyroid nodules.

The original version of this article unfortunately was incorrect. The correct title should read: "Comment to article: "Image-guided thermal ablation of benign thyroid nodules" by A. Mainini, et al. J Ultrasound (2017) https://doi.org/10.1007/s40477-016-0221-6 ".

Image-guided thermal ablation of benign thyroid nodules.

Purpose: To clarify some relevant and significant inconsistencies and inaccuracies in review by Mainini et al. entitled "Image-guided thermal ablation of benign thyroid nodules" published in Journal of Ultrasound to avoid giving incorrect information to the reader and prevent that operators make wrong choices in the use of various devices and technologies available. Results: Total cases treated with radiofrequency would be 2388 and not 2435 as reported in Table 1 of this review. The major, minor complications, and side effects in the partial group treated with laser technique and reported in this review are actually 1.2, 3.8, and 35.4%, respectively. In series of patients treated with laser ablation, including a total of 2345 patients, major and minor complications are 0.7 and 1.4%, respectively. The major complications of laser technology are less severe than RFA. Conclusions: Several points regarding the paper by Mainini et al. need to be discussed, and I advocate authors for replying to my considerations to clarify the issues raised.

The advent of ultrasound-guided ablation techniques in nodular thyroid disease: towards a patient-tailored approach.

Surgery is the long-established therapeutic option for benign thyroid nodules, which steadily grow and become symptomatic. The cost of thyroid surgery, the risk of temporary or permanent complications, and the effect on quality of life, however, remain relevant concerns. Therefore, various minimally invasive treatments, directed towards office-based management of symptomatic nodules, without requiring general anaesthesia, and with negligible damage to the skin and cervical tissues, have been proposed during the past two decades. Today, ultrasound-guided percutaneous ethanol injection and thermal ablation with laser or radiofrequency have been thoroughly evaluated, and are accessible procedures in specialized centres. In clinical practice, relapsing thyroid cysts are effectively managed with percutaneous ethanol injection treatment, which should be considered therapy of choice. In solid non-functioning thyroid nodules that grow or become symptomatic, trained operators may safely induce, with a single session of laser ablation treatment or radiofrequency ablation, a 50% volume decrease and, in parallel, improve local symptoms. In contrast, hyperfunctioning nodules remain best treated with radioactive iodine, which results in a better control of hyperthyroidism, also in the long-term, and fewer side-effects. Currently, minimally invasive treatment is also investigated for achieving local control of small size neck recurrences of papillary thyroid carcinoma in patients who are poor candidates for repeat cervical lymph node dissection. This particular use should still be considered experimental.

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.

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.

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.

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.

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.

Percutaneous laser ablation of unresectable primary and metastatic adrenocortical carcinoma.

PURPOSE: To evaluate the feasibility, safety, and clinical benefits of percutaneous laser ablation (PLA) in patients with unresectable primary and metastatic adrenocortical carcinoma (ACC). PATIENTS AND METHODS: Four patients with hepatic metastases from ACC and a Cushing's syndrome underwent ultrasound-guided PLA. In one case the procedure was performed also on the primary tumor. RESULTS: After three sessions of PLA, the primary tumor of 15 cm was ablated by 75%. After 1-4 (median 1) sessions of PLA, five liver metastases ranging from 2 to 5 cm were completely ablated, while the sixth tumor of 12 cm was ablated by 75%. There were no major complications. Treatment resulted in an improvement of performance status and a reduction of the daily dosage of mitotane in all patients. The three patients with liver metastases presented a marked decrease of 24-h urine cortisol levels, an improved control of hypertension and a mean weight loss of 2.8 kg. After a median follow-up after PLA of 27.0 months (range, 9-48 months), two patients have died of tumor progression, while two other patients remain alive and free of disease. CONCLUSIONS: Percutaneous laser ablation is a feasible, safe and well tolerated procedure for the palliative treatment of unresectable primary and metastatic ACC. Further study is required to evaluate the impact of PLA on survival.

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 patients with isolated unresectable liver metastases from colorectal cancer: Results of a phase II study.

We prospectively evaluated the safety, local tumor control, and impact on survival parameters of percutaneous laser ablation (PLA) in patients with colorectal liver metastases not amenable to surgical resection. The study included 44 individuals with 75 unresectable liver metastases and no known extrahepatic disease. The median number of metastases treated for each patient was one, with a range of 1-4. Metastases had a median diameter of 3.4 cm (range 0.5-9 cm), and a median volume of 16.8 cm(3) (range 0.4-176.4 cm(3)). All patients also received systemic chemotherapy with modalities that differed according to the type of response to PLA. After treatment, 61% (46/75) of the tumors were ablated completely. The likelihood of achieving a complete ablation was significantly higher when metastases had a diameter <3.0 cm (p = 0.004). Overall survival was 30.0+/-12.7 months in patients with a complete ablation, and 20.2+/-10.2 months in those with a partial ablation (p = 0.002). There were no major complications during or after PLA, the most frequent side effect being abdominal pain that required analgesics. These findings indicate that PLA can be safely used as an adjunct to chemotherapy in unresectable colorectal liver metastases, and may have a positive impact on survival.

Ultrasound-guided laser thermal ablation for treatment of benign thyroid nodules.

OBJECTIVE: To evaluate the efficacy of ultrasound (US)-guided laser thermal ablation (LTA) in reducing the volume of hypofunctioning benign thyroid lesions. METHODS: The criteria for entry into the study were as follows: (1) presence of a hypofunctioning thyroid nodule with a volume exceeding 8 mL, (2) benign cytologic findings, (3) local compression symptoms or patient concern, and (4) refusal of or ineligibility for surgical treatment. Twenty patients (15 women and 5 men; mean age, 63.3 +/- 14.1 years) fulfilling the entry criteria were enrolled in the study. Under US monitoring, a 75-mm, 21-gauge spinal needle was inserted into the thyroid gland, and a flat-tipped 300-microm quartz fiberoptic guide was placed through the needle into the tissues. LTA was performed with use of a 1.064-microm continuous-wave neodymium yttrium-aluminum-garnet laser that had an output power of 3 W for 10 minutes. US scans were used to assess the decrease in nodule volume at 1 month and 6 months after LTA. RESULTS: After LTA, mean nodule volume decreased from a baseline value of 24.1 +/- 15.0 mL to 13.3 +/- 7.7 mL at 1 month and to 9.6 +/- 6.6 mL at 6 months. Mean nodule volume reduction in comparison with baseline was 43.8 +/- 8.1% at 1 month and 63.8 +/- 8.9% at 6 months. LTA induced burning cervical pain, which rapidly decreased after the laser energy was turned off. Three patients (15%) required treatment with betamethasone for 48 hours. No patient had local bruising, cutaneous burning, or dysphonia. CONCLUSION: LTA may be an effective procedure for the treatment of benign cold thyroid nodules that cause pressure symptoms in patients who are not candidates for surgical treatment or who refuse to undergo a surgical procedure.

Risk of malignancy in nonpalpable thyroid nodules: predictive value of ultrasound and color-Doppler features.

The aim of the study was to correlate the sonographic [ultrasound (US)] and color-Doppler (CFD) findings with the results of US-guided fine needle aspiration biopsy (FNA) and of pathologic staging of resected carcinomas to establish: 1) the relative importance of US features as risk factors of malignancy; and 2) a cost-effective management of nonpalpable thyroid nodules. Four hundred ninety-four consecutive patients with nonpalpable thyroid nodules (8-15 mm) were evaluated by US, CFD, and US-FNA. Ninety-two patients with inadequate cytology were excluded from the study. All patients with suspicious or malignant cytology underwent surgery, whereas subjects with benign cytology had clinical and US control 6 months later. Thyroid malignancies were observed in 18 of 195 (9.2%) solitary thyroid nodules and in 13 of 207 (6.3%) multinodular goiters. Cancer prevalence was similar in nodules greater or smaller than 10 mm (9.1 vs. 7.0%). Extracapsular growth (pT(4)) was present in 35.5%, and nodal involvement in 19.4% of neoplastic lesions, with no significant differences between tumors greater or smaller than 10 mm. At US cancers presented a solid hypoechoic appearance in 87% of cases, irregular or blurred margins in 77.4%, an intranodular vascular pattern in 74.2%, and microcalcifications in 29.0%. Irregular margins (RR 16.83), intranodular vascular spots (RR 14.29), and microcalcifications (RR 4.97) were independent risk factors of malignancy. FNA performed on hypoechoic nodules with at least one risk factor was able to identify 87% of the cancers at the expence of cytological evaluation of 38.4% of nonpalpable lesions. The majority of nonpalpable thyroid tumors can be identified by cytological evaluation of lesions presenting hypoechoic appearance in conjunction with one independent risk factor. Due to the nonnegligible prevalence of extracapsular growth and nodal metastasis, US-FNA should be performed on all 8-15 mm hypoechoic nodules with irregular margins, intranodular vascular spots or microcalcifications. Nonpalpable lesions of the thyroid without risk factors should be followed by means of clinical and US evaluation.