Blood leukocytes as a non-invasive diagnostic tool for thyroid nodules: a prospective cohort study.

BACKGROUND: Thyroid nodule (TN) patients in China are subject to overdiagnosis and overtreatment. The implementation of existing technologies such as thyroid ultrasonography has indeed contributed to the improved diagnostic accuracy of TNs. However, a significant issue persists, where many patients undergo unnecessary biopsies, and patients with malignant thyroid nodules (MTNs) are advised to undergo surgery therapy. METHODS: This study included a total of 293 patients diagnosed with TNs. Differential methylation haplotype blocks (MHBs) in blood leukocytes between MTNs and benign thyroid nodules (BTNs) were detected using reduced representation bisulfite sequencing (RRBS). Subsequently, an artificial intelligence blood leukocyte DNA methylation (BLDM) model was designed to optimize the management and treatment of patients with TNs for more effective outcomes. RESULTS: The DNA methylation profiles of peripheral blood leukocytes exhibited distinctions between MTNs and BTNs. The BLDM model we developed for diagnosing TNs achieved an area under the curve (AUC) of 0.858 in the validation cohort and 0.863 in the independent test cohort. Its specificity reached 90.91% and 88.68% in the validation and independent test cohorts, respectively, outperforming the specificity of ultrasonography (43.64% in the validation cohort and 47.17% in the independent test cohort), albeit with a slightly lower sensitivity (83.33% in the validation cohort and 82.86% in the independent test cohort) compared to ultrasonography (97.62% in the validation cohort and 100.00% in the independent test cohort). The BLDM model could correctly identify 89.83% patients whose nodules were suspected malignant by ultrasonography but finally histological benign. In micronodules, the model displayed higher specificity (93.33% in the validation cohort and 92.00% in the independent test cohort) and accuracy (88.24% in the validation cohort and 87.50% in the independent test cohort) for diagnosing TNs. This performance surpassed the specificity and accuracy observed with ultrasonography. A TN diagnostic and treatment framework that prioritizes patients is provided, with fine-needle aspiration (FNA) biopsy performed only on patients with indications of MTNs in both BLDM and ultrasonography results, thus avoiding unnecessary biopsies. CONCLUSIONS: This is the first study to demonstrate the potential of non-invasive blood leukocytes in diagnosing TNs, thereby making TN diagnosis and treatment more efficient in China.

Investigating the optimal maximum diameter of benign thyroid nodules for thermal ablation on the basis of complete disappearance rate.

OBJECTIVE: Thermal ablation (TA) is a safe and effective treatment for benign thyroid nodules (BTNs). However, there has been no consensus on the optimal maximum diameter (MD) of BTNs for TA. This study aimed to identify the optimal MD of BTNs for TA based on complete disappearance rate after TA. MATERIALS AND METHODS: This retrospective study included 639 BTNs treated with TA from June 2014 to January 2022. The complete disappearance rate of BTNs after TA was summarized, related influencing factors were explored, and the optimal MD of BTNs for TA was identified. RESULTS: At the final follow-up (median: 40 months, range: 24-95 months), the overall volume reduction rate was 95.4 ± 9.0%, and 50.5% of the BTNs (323/639) completely disappeared. The MD was significantly negatively correlated with complete disappearance (odds ratio 0.89, 95% confidence interval 0.87-0.92; p < 0.001). Calcification, comet-tail artifacts, multilocular cysts, and composition of BTNs, as well as diabetes were negatively correlated with complete disappearance. Restricted cubic spline indicated that an MD of 25.0 mm was the optimal threshold of BTNs for TA, which was confirmed by subgroup logistic regression analysis. Compared with BTNs with MD ≤ 25.0 mm, those with MD > 25.0 mm had a greater complication rate (6.5% vs. 2.4%, p = 0.012). CONCLUSIONS: The MD of BTNs was negatively correlated with complete disappearance after TA; an MD > 25.0 mm indicated a reduced likelihood of complete disappearance compared with an MD ≤ 25.0 mm. An MD of 25.0 mm is an appropriate threshold of BTNs for TA on the basis of complete disappearance rate.

Influence factors and nomogram for volume reduction rate in benign thyroid nodule after thermal ablation.

BACKGROUND: Thermal ablation is a minimally invasive and safe treatment for benign thyroid nodules, and the volume reduction rate (VRR) of nodule is a primary clinical efficacy indicator. PURPOSE: To screen factors influencing VRR in benign thyroid nodules after thermal ablation and establish a predictable nomogram. MATERIALS AND METHODS: This retrospective study enrolled 238 patients with benign thyroid nodules who underwent thermal ablation between January 2016 and September 2021. Clinical information and imaging characteristics in routine ultrasound (US) and contrast-enhanced ultrasound (CEUS) were evaluated. Factors influencing the VRR ≥75% were screened using multivariate logistic regression, and a predictable nomogram was established. RESULTS: At the 12-month follow-up, the VRR of nodule was 77.0 ± 20.6% (18.4-100%). Seven factors influencing the VRR ≥75.0% were identified: echogenicity, component, calcification, enhancement degree, enhancement defect, ring enhancement, and energy of ablation. A nomogram was established based on the above factors, and the predictive ability of the model was confirmed by internal validation with 1000 bootstrap repetitions. The area under the receiver-operating characteristic curve (AUC) of the model was 0.926, and the calibration curve and decision curve analysis (DCA) revealed that this model demonstrated predictive ability. CONCLUSION: Seven factors influencing VRR in benign thyroid nodules after thermal ablation were screened out in the present study and used to establish a nomogram to predict the probability of VRR ≥75% at the 12-month follow-up. It would be beneficial to make personalized medical decisions to trigger thermal ablation in patients with benign thyroid nodules.

High-intensity focused ultrasound for benign thyroid nodules: Systemic review and meta-analysis.

BACKGROUND: High-intensity focused ultrasound (HIFU) is a less invasive option offered for the treatment of large, compressive, benign thyroid nodules. METHODS: Observational studies of more than five participants using HIFU in the management of benign thyroid nodules from 2000 to 2021 were identified using predefined inclusion criteria. The primary outcome was an estimate of the effectiveness of HIFU. RESULTS: Out of 158 studies reviewed, 8 articles were included with 297 patients and 300 nodules. HIFU significantly reduced nodule volume from 1 to 24 months following therapy (weighted mean difference [WMD], 47.68, 95 % confidence interval [CI], 34.13-59.66, p < 0.0001) and achieved favorable success rates (risk ratio [RR], 1.49, 95 % CI, 1.15-1.84, p < 0.001) for 50 % volume reduction. CONCLUSIONS: HIFU appears to be a feasible, safe, and effective treatment modality for patients with benign thyroid nodules. Future research, including randomized controlled trials, is needed to determine therapy optimization, and patient selection to identify the potential role of this new therapy.

Factors related to the absorption rate of benign thyroid nodules after image-guided microwave ablation: a 3-year follow-up.

PURPOSE: To assess the absorption rate and factors related to the development of benign thyroid nodules (BTNs) following image-guided microwave ablation (MWA). MATERIALS AND METHODS: This retrospective study reviewed nodule efficacy in patients who underwent MWA of BTNs between January 2016 and January 2018. The endpoint was a third-year follow-up. Nodules were categorized into those showing complete absorption (volumes with less than 100% volume reduction ratio (VRR) and those showing partial absorption (100% VRR)). Univariable and multivariable regression analyses were carried out to identify variables that were associated with nodule absorption rates. RESULTS: A total of 173 BTNs (median volume= 4.23 ml; 25-75 percentiles= 2.27-9.00 ml) from 173 patients were evaluated. 49.7% (86/173) of patients had nodules that became completely absorbed. The mean VRRs of all BTNs were 18.0%, 78.7%, 89.0%, 94.5%, and 97.1% at the 1-, 6-,12-, 24- and 36- month follow-ups. At the 3-year follow-up time point, nodule characteristics related to nodule VRR included nodule volume (adjusted odds ratio [AOR], 1.1 [95% CI: 1.0, 1.2]; p = 0.03) and nodule margin (AOR, 5.3 [95% CI: 1.8, 16.0]; p < 0.01). Treatment-related characteristics included energy per ml in nodular volume (AOR, 1.0 [95% CI: 1.0, 1.0]; p < 0.01) and blockage of peripheral flow (AOR, 3.3 [95% CI: 1.3 8.3]; p = 0.01). CONCLUSIONS: US-guided image-guided MWA results in satisfactory long-term outcomes for the patients with BTNs. Factors related to nodule absorption rate were the volume and margin of the nodule, energy per ml in nodular volume and blockage of peripheral flow.

Efficacy and safety of radiofrequency ablation for calcified benign thyroid nodules: results of over 5 years' follow-up.

PURPOSE: To evaluate the efficacy and safety of radiofrequency ablation (RFA) for treating calcified benign thyroid nodules (CBTNs). METHODS: Fifty-two patients with 52 CBTNs who underwent RFA in our hospital were included in this retrospective study. According to the size of calcifications, CBTNs were divided into two groups: the punctate echogenic foci (PEF) group and macrocalcification group. Moreover, the macrocalcification group was further subdivided into two groups, the strong group and the weak group, based on their morphologic characteristics. After the RFA procedure, routine ultrasound (US) and clinical evaluation were performed at 1, 3, 6 and 12 months postoperatively and every 12 months thereafter. RESULTS: The mean follow-up time was 68.98 ± 7.68 months (60-87 months), and the 5-year mean volume reduction rate (VRR) after RFA was 92.95%, with a complication rate of 0.6% (3/52). The mean initial volume of the macrocalcification group was significantly larger than that of the PEF group (9.94 ± 24.60 ml vs. 0.23 ± 0.22 ml, respectively; P = 0.011). Thus, their VRRs were not comparable between the two groups. However, baseline characteristics did not show statistically significant differences between the strong and weak macrocalcification subgroups. The VRRs of the strong subgroup were significantly lower than those of the weak subgroup at the 3-year, 4-year, and 5-year follow-ups. CONCLUSION: RFA was effective and safe for treating CBTNs. Strong macrocalcification was related to the VRR of CBTNs after the RFA procedure.

Preoperative platelet distribution width-to-platelet ratio combined with serum thyroglobulin may be objective and popularizable indicators in predicting papillary thyroid carcinoma.

OBJECTIVES: The incidence of papillary thyroid carcinoma (PTC) has increased more rapidly than that of any other cancer type in China. Early indicators with high sensitivity and specificity during diagnosis are required. To date, there has been a paucity of studies investigating the relationship between preoperative platelet distribution width-to-platelet count ratio (PPR) and PTC. This study thus aimed to assess the diagnostic value of PPR combined with serum thyroglobulin (Tg) in patients with PTC. METHODS: A total of 1001 participants were included in our study. 876 patients who underwent surgery for nodular goiter were divided into the PTC group or benign thyroid nodule (BTN) group according to pathology reports, and 125 healthy controls (HCs) were included. Preoperative hemogram parameters and serum Tg levels were compared among three groups. Receiver operating characteristic (ROC) curve was used to evaluate the value of PPR combined with serum Tg for diagnosing PTC. RESULTS: Platelet distribution width (PDW) and PPR levels were higher in the PTC group than in the BTN and HC groups (both p < 0.05) but did not significantly differ between the BTN and HC groups. PDW and PPR levels significantly differed in the presence/absence of lymph node metastasis, the presence/absence of capsule invasion (p = 0.005), and TNM stages (p < 0.001). Multivariable analyses indicated that high serum Tg levels [adjusted odds ratio (OR), 1.007; 95% confidence interval (CI), 1.004-1.009; p < 0.001], high neutrophil-to-lymphocyte ratio (NLR,adjusted OR, 1.928; 95% CI, 1.619-2.295; p < 0.001), and high PPR (adjusted OR, 1.378; 95% CI, 1.268-1.497; p < 0.001) were independent risk factors for PTC. In ROC analysis, the areas under the curves (AUCs) of serum Tg, PDW, PPR, and NLR for predicting PTC were 0.603, 0.610, 0.706, and 0.685, respectively. PPR combined with serum Tg (PPR + Tg) had a higher diagnostic value (AUC, 0.738; sensitivity, 60%; specificity, 74.7%) compared with PDW + Tg (AUC, 0.656; sensitivity, 64.4%; specificity, 59.9%) and NLR + Tg (AUC, 0.714; sensitivity, 61.6%; specificity, 71.1%). CONCLUSIONS: Preoperative PPR combined with serum Tg may be objective and popularizable indicators for effective predicting PTC.

Radiofrequency ablation versus reoperation for benign thyroid nodules that developed after previous thyroid surgery.

PURPOSE: To compare the clinical outcomes of radiofrequency ablation (RFA) versus reoperation for benign thyroid nodules that developed after previous thyroid surgery. METHODS: A total of 53 patients with 53 benign nodules developed after previous thyroid surgery were evaluated in this retrospective study. Eighteen patients were treated by RFA (RFA group) and 35 patients underwent reoperation (reoperation group). The efficacy, safety, thyroid function, blood loss, hospitalization, total treatment time, and cost were compared between the two groups. RESULTS: In the RFA group, the mean volume decreased significantly from 12.78 ± 17.57 ml to 0.94 ± 1.01 ml (p = 0.043) with a volume reduction rate of 85.27 ± 14.35% and significant improvement in symptom and cosmetic scores (all p = 0.001). Therapeutic efficacy was achieved with a single session in all thyroid nodules. The total treatment time (6.12 ± 3.17 min vs. 110.26 ± 44.41 min, p < 0.001), blood loss (0 ml vs. 82.58 ± 105.55 ml, p < 0.001) and hospitalization(0 days vs. 9.66 ± 4.28 days, p < 0.001) were significantly lower in the RFA group than those in reoperation group, but the costs of treatment were similar(2262.12 ± 221.54 USD vs. 2638.04 ± 1062.90 USD, p = 0.081). The incidence of complications was significantly higher in the reoperation group than in the RFA group(31.43 vs. 0%, p < 0.001). Furthermorre, 65.17% of patients developed hypothyroidism after reoperation, whereas the thyroid function of the patients in the RFA group was unaffected. CONCLUSION: For patients with benign thyroid nodules developed after previous thyroid surgery, RFA can be considered as a safe and effective alternative to reoperation with advantages of maintenance of intact thyroid function and low incidence of complications.

Efficacy and safety of radiofrequency ablation for benign thyroid nodules in patients with previous thyroid lobectomy.

BACKGROUND: Radiofrequency ablation (RFA) is recommended for the treatment of benign thyroid nodules. However, data on the clinical role of RFA for benign thyroid nodules in patients with history of thyroid lobectomy are insufficient. The purpose of this study was to evaluate the efficacy and safety of radiofrequency ablation (RFA) for benign thyroid nodules in patients who had previously undergoing thyroid lobectomy. METHODS: From May 2015 to October 2018, a total of 20 patients (19 females, 1 male, mean age 49.50 ± 14.26 years, range 22-74 years) with 20 benign thyroid nodules (mean volume 15.04 ± 21.17 ml, range 0.40-69.67 ml) who had undergone previous thyroid lobectomy were included in this retrospective study. Patients were followed up at 3, 6, 12 months after RFA and every 12 months thereafter by ultrasound, clinical evaluation and thyroid function. Volume, volume reduction rate (VRR), symptom score and cosmetic score were evaluated. RESULTS: During the mean follow-up time of 21.24 ± 16.41 months, the mean nodule volume decreased significantly from 15.04 ± 21.17 ml to 1.29 ± 1.17 ml (P = 0.018) with a mean VRR of 85.41 ± 12.17%. Therapeutic success was achieved in a single session for all thyroid nodules. The symptom score (P = 0.001) and cosmetic score (P = 0.001) were both significantly reduced at the last follow-up. The levels of free triiodothyronine (fT3), free thyroxine (fT4) and thyroid stimulating hormone were not significantly different at the last follow-up from those prior to treatment (all P > 0.05). No life-threatening complications or sequelae occurred after RFA. CONCLUSIONS: As a minimally invasive modality, RFA was a safe, effective, and thyroid function-preserving option for patients with symptomatic benign thyroid nodules after a previous lobectomy.

Effects of energy-based ablation on thyroid function in treating benign thyroid nodules: a systematic review and meta-analysis.

BACKGROUND: Whether thyroid function would be affected by ablation remains controversial. This systematic review and meta-analysis aimed to investigate the effects of energy-based ablation on thyroid function in treating benign thyroid nodules. METHODS: EMBASE, PubMed, Cochrane Library, and Web of Science databases were searched. The mean difference (MD) or standard MD (SMD) was applied to assess changes in thyroid function, thyroglobulin (Tg), and antibodies after ablation. RevMan version 5.3 was used for data synthesis. RESULTS: Forty-two studies involving 6380 patients were eligible. The pooled results revealed significant decrease of 1-day thyroid-stimulating hormone (95% CI, -0.67 to -0.14), significant increase of 1-day, 1-week, and 1-month free thyroxine (95% CI, 1.57 to 5.28; 95% CI, 0.61 to 2.42; 95% CI, -0.76 to -0.15), 1-day and 1-week Tg level (95% CI, 0.40 to 0.81; 95% CI, 0.21 to 1.29), 6-month anti-thyroglobulin antibodies (95% CI, 0.02 to 0.26), 1- and 3-month thyroperoxidase antibody (95% CI, 0.02 to 0.22; 95% CI, 0.17 to 0.43), and 1-day, 1-, and 3-month thyrotrophin receptor antibody (95% CI, 0.10 to 0.43; 95% CI, 0.00 to 0.30; 95% CI, 0.13 to 0.36) after ablation. No statistically significant differences were found in these six indicators in the longer term. The results of subgroup analysis were similar to the pooled results. No significant publication bias was found. CONCLUSIONS: Energy-based ablation was more likely to have negative effects on thyroid function and antibodies and led to transient increase in Tg level in the short term. However, most of the patients would not develop any thyroid dysfunction in the long-term follow-up.

High-intensity focused ultrasound (HIFU) therapy for benign thyroid nodules: a 3-year retrospective multicenter follow-up study.

BACKGROUND: Outcomes of high-intensity focused ultrasound (HIFU), as a non-surgical treatment option for benign symptomatic thyroid nodules, has mainly been based on single-center studies and short-term follow-up. Therefore, we assessed the safety, and long-term efficacy of HIFU in benign thyroid nodules among four centers with expertise in thyroid mini-invasive procedures. PATIENTS AND METHODS: Retrospective three year follow-up study in four European centers, treating solid benign thyroid nodules causing pressure symptoms and/or cosmetic concerns. Nodule volume reduction was assessed at 1, 3, 6, 12, 24, and 36 months post-treatment. Technical efficacy, defined as a volume reduction rate (VVR) >50% was evaluated at 6, 12, 24 and 36 months. Predictive factors of efficacy were assessed using logistic models. Complications and side effects were classified according to the Interventional Radiology Guidelines and changes in local symptoms were scored on a visual-analog scale. RESULTS: Sixty-five patients (mean age 51.1 ± 14.0 years; 86.2% women) with a single thyroid nodule and a mean baseline nodule volume of 9.8 ± 10.3 mL were treated with a mean energy of 7.1 ± 3.1 kJ (range: 2.0 to 15.5 kJ). Median nodule volume reduction was 31.5% (IQR: -38.6% to -23.1%) at 12 months and 31.9% (IQR: -36.4% to -16.1%) at 36 months. Technical efficacy was obtained in 17.2% of cases at 6 months, 17.8% at 12 months, 3.4% at 24 months, and 7.4% at 36 months. The number of treated pixels and the mean energy delivered were positively correlated to VRR at 1, 6 and 12 months. The risk of treatment failure decreased by 4.3% for each additional unit of energy delivered. The procedure duration was inversely correlated with treatment failure (OR 1.043, 95% CI: 1.011-1.083; p = 0.014). Improvement of cervical pressure symptoms or cosmetic complaints were observed in less than 15% of the cases at 12, 24 and 36 months. Horner's syndrome occurred in one case (1.5%) and minor complications, not requiring treatment, in three (4.6%) patients. No change in thyroid function was registered. CONCLUSIONS: HIFU carried a low risk of complications. A single treatment resulted in a 30-35% thyroid nodule volume decrease within one year, reduction that remained stable for 2 years. Outcomes varied significantly between centers with different HIFU expertise. Focus on improved HIFU technology, adequate training, and appropriate selection of patients is needed to achieve efficacy comparable to other thermal ablation procedures.

Roles of contrast-enhanced ultrasonography in identifying volume change of benign thyroid nodule and optical time of secondary radiofrequency ablation.

BACKGROUND: Ultrasonography-guided radiofrequency ablation (RFA) was was proved to be an effective and safe treatment with few complications for benign thyroid nodule. In cases of incompletely treated nodule margin, secondary RFAs are necessary. The present study was designed to analyze the dynamic change of nodular volume of benign thyroid tumors accessed using contrast-enhanced ultrasonography (CEUS) after RFA, and hopefully to offer evidence for time decision of secondary RFA. METHODS: A total of 105 patients who received ultrasonography-guided RFA in the Department of Ultrasound, Chinese PLA General Hospital between April 2014 and August 2018 for benign thyroid nodule were enrolled in this retrospective study. Vt increase (regrowth) and vital volume (Vv) of thyroid nodule were followed up at 0, 1, 3, 6, 12, 24 and 36 months after RFA. RESULTS: A total of 105 nodules of 105 patients were enrolled in the present study, with a mean age of 46.70 ± 13.05 years, and 87 of them (82.9%) were female. The median follow up time was 25.1 months (12 months to 36 months). During the follow up, regrowth occurred in 43 cases, 95.35% of nodular regrowth occurred in 12 months after RFA, and the rate showed substantial consistency with that on the 36th month postoperatively (Kappa = 0.656). CONCLUSIONS: CEUS was an effective and safe tool to monitor volume change of benign thyroid nodules after RFA. The majority cases of regrowth occurred in 12 months after RFA, thus, the 12th month after RFA might be the optimal time for volume assessment to make the decision of secondary RFAs.

Safety and efficacy of thermal ablation (radiofrequency and laser): should we treat all types of thyroid nodules? †.

Background: Thermal ablation is a minimally invasive technique that is gradually acknowledged as an effective alternative to surgery to treat thyroid nodules. Two main techniques have been described: radiofrequency (RFA) and laser ablation. Objective: To evaluate the safety and efficacy of the two main techniques (RFA and laser ablation) for the treatment of benign thyroid nodules. Patients: This bicentric retrospective study included 166 consecutive patients, who received clinical, biological and ultrasound evaluations for thyroid nodules, from October 2013 to November 2017. Methods: One of the two techniques was proposed if a nodule was proven to be benign after fine needle aspiration cytology or micro-biopsy. Adverse events and outcomes (symptoms, nodule reduction) were assessed at 6 weeks and 6, 12, and 18 months after treatment. Results: One hundred and eighty-nine nodules (mean size 17.5 ± 16.9 mL, 86.1% palpable) were treated by RFA (n = 108 (57.1%)) or laser ablation (n = 81 (42.9%)) in 166 patients (80.1% women, mean age 51.7 years). Two cases of transient recurrent laryngeal nerve palsy, one hematoma, and two successfully drained abscesses (5/166 = 3%) were observed. Clinical symptoms improved significantly in the two groups (anterior cervical discomfort -83.6%, esthetic complaints -84.9% and dysphagia -86.4%). Nodule volume (mL) decreased significantly (baseline vs. 18 months) from 20.4 ± 18.6 to 5.8 ± 6.6 (-75%) in the RFA, and from 13.6 ± 13.3 to 3.4 ± 4.1 (-83.9%) in the laser ablation groups. Conclusions: Transient but potentially serious adverse events were reported in 3% of patients. A significant volumetric reduction was achieved with both techniques, regardless of nodule's characteristics, at 18 months.

Microwave ablation compared to thyroidectomy to treat benign thyroid nodules.

OBJECTIVE: Benign thyroid nodules occur commonly but only require treatment when symptomatic. Surgical treatment, once routine, has been replaced by newer technologies, such as microwave ablation (MWA). The aim of this study was to assess the efficacy, tolerability and cost of MWA compared to surgery to treat benign thyroid nodules. METHODS: After obtaining ethical approval and informed consent, a prospective trial was conducted with 52 patients who had symptomatic benign thyroid nodules. Patients were randomly assigned to receive MWA or surgical treatment. The volume reduction ratio (VRR), thyroid function, complications, HRQoL, costs and some parameters were compared. RESULTS: MWA reduced mean nodule volume by 72.3% at 3 months, 84.5% at 6 months and 92.4% at 12 months as effective as surgery in inactivating nodules, and thyroid dysfunction did not occur during 12-month follow-up for those receiving MWA. Although both MWA and surgery were safe, patients undergoing MWA had fewer cases of complications and rarely reported pain. The MWA group was superior to the surgery group in length of stay, postoperative scar length and the operation time. Compared to patients who underwent surgery, those who underwent MWA had better general health and mental health scores at 6 months and 12 months. The mean total cost of the MWA group was lower than that of the surgery group. CONCLUSION: MWA can significantly reduce nodule volume and nodule-related symptoms with more rapid recovery, more pleasing esthetic outcomes, less physiologic disruption and less expense compared to the surgery.

Microwave ablation induces a lower systemic stress response in patients than open surgery for treatment of benign thyroid nodules.

OBJECTIVE: In this study, we compared the systemic stress response induced by microwave ablation with that induced by conventional open surgery for treatment of benign thyroid nodules. METHODS: A total of 108 patients with benign thyroid nodules were randomly assigned to receive ultrasound-guided thyroid microwave ablation (microwave group, n = 57) and conventional open thyroid surgery (open group, n = 51). Body temperature, white blood cell (WBC) counts, visual analogue scale (VAS) scores for pain, and serum levels of high sensitive C-reactive protein (hs-CRP), interleukin 6 (IL-6) and cortisol were measured at 24 h before operation and at 8 h, 24 h and 48 h after operation. RESULTS: No significant between-group differences were observed with respect to preoperative body temperature, VAS scores, WBC counts, serum hs-CRP, IL-6 and cortisol levels. Patients in the open group exhibited higher body temperature at 24 h after operation and higher WBC counts at both 24 h and 48 h after operation, as compared to those in the microwave group. As compared with microwave ablation, open surgery was associated with significantly higher VAS scores, and significantly higher serum levels of hs-CRP, IL-6 and cortisol at all postoperative time-points (8 h, 24 h and 48 h). CONCLUSION: Microwave ablation induces a lower systemic stress response than open surgery for treatment of benign thyroid nodules.

Changes in serum thyroglobulin and antithyroglobulin shortly following high-intensity focused ablation of benign thyroid nodules in patients with positive antithyroglobulin status.

BACKGROUND: We aimed to describe changes in serum thyroglobulin (Tg) and anti-Tg autoantibody shortly following high-intensity focused ultrasound (HIFU) ablation in patients with positive anti-Tg status by comparing them with patients with negative anti-Tg and to correlate them with 6-month nodule shrinkage and treatment success. METHODS: From 2015 to 2017, patients who underwent HIFU ablation of a benign thyroid nodule were analysed. Serum Tg and anti-Tg were checked on treatment day (baseline) and 4 days after treatment. Anti-Tg >99 IU/ml were considered positivity. Percentage Tg or anti-Tg change = [Level on Day-4 - baseline level]/[Baseline level] × 100 while nodule shrinkage was measured by volume reduction ratio (VRR) = [Baseline volume - volume at 6 month]/[Baseline volume] × 100. Treatment success was defined as VRR >50%. RESULTS: Among the 276 eligible patients, 85 (30.8%) patients were positive for anti-Tg (Group I) while the others (n = 191, 69.2%) were negative (Group II). Relative to group II, Group I had a less significant Tg rise on Day 4 (4121.78 ± 9321.90% vs. 5711.53 ± 23487.20%, p = .013). There was a fall in anti-Tg on day 4 for group I (-11.56 ± 139.69%). This percentage anti-Tg drop significantly correlated with the 6-month VRR (ρ = -0.602, p = .030) but was not a significant factor of treatment success. CONCLUSIONS: Given the fact that the percentage anti-Tg drop correlated significantly with 6-month nodule shrinkage in group I, monitoring early anti-Tg change may help to predict the 6-month nodule shrinkage in patients with positive anti-Tg.

Complications encountered in ultrasonography-guided radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers.

OBJECTIVES: To evaluate the complication rates and describe the possible complications of ultrasonography-guided radiofrequency ablation (RFA) of benign thyroid nodules (BTN) and recurrent thyroid cancers (RTC), and to compare the complication rates between BTN and RTC. METHODS: This retrospective study reviewed 875 patients who underwent RFA for BTN (746 patients; 83.5%) or RTC (129 patients; 14.7%). Medical records were reviewed for all types of complications occurring during and after the RFA procedure. The baseline characteristics and the complication rates of BTN and RTC were compared. RESULTS: The overall complication rate was 3.5% (31/875), and the major complication rate was 1.6% (14/875). The major complication rate of RTC was significantly higher than that of BTN (5.4% vs. 0.9%, P = 0.002), while there were no significant differences in the minor complications rate. New complications, such as Horner syndrome, spinal accessory nerve injury, and complications due to lidocaine toxicity, were also revealed. CONCLUSIONS: Various complications of RFA may occur in both BTN and RTC, although the complication rate is low. To understand the broad spectrum of complications and minimise the complications and sequela, the suggested technical tips and cervical anatomy are essential. KEY POINTS: • The overall complication rate was 3.5% (31/875). • The major complication rate was 1.6% (14/875). • The major complication rate of RTC was significantly higher than BTN. • There were only four patients showing persistent symptoms (0.5%). • Unreported new complications were also demonstrated.

The percentage of serum thyroglobulin rise in the first-week did not predict the eventual success of high-intensity focussed ablation (HIFU) for benign thyroid nodules.

BACKGROUND: Given that high-intensity focussed ultrasound (HIFU) of benign thyroid nodules often causes a massive release of thyroglobulin (Tg) into the circulation, we hypothesised a greater initial Tg rise may result in a greater nodule shrinkage 6 months after ablation. METHODS: One hundred and five patients who underwent HIFU for symptomatic benign thyroid nodule from 2015 to 2016 were analysed. Serum Tg and anti-Tg autoantibody were checked on treatment day (baseline) and 4 d after treatment. The % of Tg rise = [serum Tg on day-4 - baseline serum Tg]/[baseline serum Tg] * 100 while the nodule shrinkage as measured by volume reduction ratio (VRR) = [baseline volume - volume at 6-month]/[baseline volume] * 100. Treatment success was defined as VRR >50%. RESULTS: At 6-month, the mean VRR was 62.2 ± 25.0% and 59 (76.6%) patients had treatment success. The mean baseline Tg level increased from 292.8 ± 672.7 ng/mL to 2022.7 ± 1759.8 ng/mL in the first-week. The % of Tg rise did not significantly correlate with either 3-month or 6-month VRR (p = 0.920 and p = 0.699, respectively). The mean % of Tg rise in the first week was not different between those with and without 6-month treatment success (368.2% vs. 1068.7%, p = 0.381). No clinical factors significantly correlated with treatment success. CONCLUSIONS: There was an almost seven-fold increase in the mean Tg level 4 d after HIFU ablation. The % of Tg rise in the first week did not appear to correlate with the 6-month nodule shrinkage or treatment success.

Radiofrequency ablation of benign thyroid nodules: depicting early sign of regrowth by calculating vital volume.

OBJECTIVE: We evaluated long-term follow-up results of radiofrequency ablation of benign thyroid nodules to analyse the role of marginal vital tissue on nodule regrowth. MATERIALS AND METHODS: We reviewed the medical records of 54 patients who underwent radiofrequency ablation between June 2008 and November 2013 with pressure symptoms, and/or cosmetic problems. All patients were followed up at least 12 months on three occasions. To evaluate an early sign of regrowth, three types of nodule volumes (total volume, ablated volume and vital volume) were measured and calculated using ultrasonography. Regrowth was defined as a more than a 50% increase in the total volume and vital volume increase was defined as a more than 50% increase compared to the previously reported smallest volume on ultrasonography. RESULTS: The mean follow-up period was 39.4 ± 21.7 (range, 13-87) months. Vital volume increases occurred in 31 nodules (57.4%) and there was regrowth in 13 nodules (24.1%). The mean timing of the vital volume increase was 27.5 ± 18.5 months, and for regrowth it was 39.9 ± 17.5 months. Vital volume increase tended to precede regrowth. CONCLUSION: Vital volume increase tended to occur earlier than regrowth and might be an early sign of regrowth in following-up after the radiofrequency ablation of benign thyroid nodules.

Safety of radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: a systematic review and meta-analysis.

OBJECTIVE: We performed a systematic review and meta-analysis to evaluate the safety of radiofrequency ablation (RFA) for the treatment of benign thyroid nodules and recurrent thyroid cancers. MATERIALS AND METHODS: Ovid-MEDLINE, EMBASE, and Library of Cochrane databases were searched up to 12 July 2016 for studies on the safety of RFA for treating benign thyroid nodules or recurrent thyroid cancers. Pooled proportions of overall and major complications were assessed using random-effects modelling. Heterogeneity among studies was determined using the χ2 statistic for the pooled estimates and the inconsistency index I2. RESULTS: A total of 24 eligible studies were included, giving a sample size of 2421 patients and 2786 thyroid nodules. 41 major complications and 48 minor complications of RFA were reported, giving a pooled proportion of 2.38% for overall RFA complications [95% confidence interval (CI): 1.42%-3.34%] and 1.35% for major RFA complications (95% CI: 0.89%-1.81%). There were no heterogeneities in either overall or major complications (I2 = 1.24%-21.79%). On subgroup analysis, the overall and major complication rates were significantly higher for malignant thyroid nodules than for benign thyroid nodules (p = 0.0011 and 0.0038, respectively). CONCLUSIONS: RFA was found to be safe for the treatment of benign thyroid nodules and recurrent thyroid cancers.