Cystic Thyroid Nodules Research Articles

Ultrasound characteristics of partially cystic thyroid nodules and their relationship with differential diagnosis of the lesions

To explore the ultrasound (US) findings of partially cystic thyroid nodules (PCTNs) and to analyze their relationship with differential diagnosis of benign and malignant lesions. 265 cases of PCTNs confirmed by needle biopsy or surgical pathology were included in this study. Their ultrasound characteristics were reviewed and their significance in differential diagnosis was analyzed. In the 265 PTCNs, 53 cases were malignant and 212 cases were benign lesions. According to the comparison of ultrasound and pathology results, there were 51 true-positive cases, 208 true negative cases, four false-positive cases and two false negative cases;the sensitivity was 96.2% (51/53), specificity was 98.1% (208/212), positive predictive value (PPV) was 92.7% (51/55), negative predictive values (NPV) was 99.0% (208/210), and accuracy rate was 97.7% (259/265). In terms of the PTCNs, internal structure, shape and margin were significantly associated with malignant or benign nature (P < 0.001); the aspect ratio ≥ 1, spiculated or micro-lobulated margin were significantly associated with malignancy; while the smooth margin, spongiform structure were significantly associated with benign nature. In terms of the internal solid portion of the nodules, the configuration, free margin, echogenecity, and calcification were significantly associated with malignant or benign nature (P < 0.001). The eccentric configuration with an acute angle, non-smooth free margin, hypoechogenecity, marked hypoechogenecity and micro-calcification were significantly associated with malignancy; while concentric configuration, smooth free margin, hyper/isoechogenicity, free margin of the solid component, and macro-calcifications were significantly associated with benign nature (P < 0.01). The results of logistic regression analysis showed that the echogenicity, free margin, configuration and calcification of the solid component were important predictive factors of malignant lesions (P < 0.05), that the hypoechogenecity, marked hypoechogenecity, eccentric configuration with an acute angle, non-smooth free margin and micro-calcification of the internal solid portion of the nodules were predictors for malignant PTCNs (P < 0.01). Understanding the characteristics of US findings of partially cystic thyroid nodules is of great importance to make an accurate diagnosis of malignant nodules.

Usefulness of Two-Stage Ethanol Ablation in the Treatment of Benign Predominantly Cystic Thyroid Nodules

The management of benign predominantly cystic thyroid nodules (PCTNs) differs depending on the institution or practitioner. This study aimed to assess the efficacy of two-stage ultrasound (US)-guided ethanol ablation (EA) in treating PCTNs. Over a 1-year period, two-stage EA was performed on benign PCTNs for 25 patients. After EA, each patient was followed up with thyroid US. The two-stage EA treatment consisted of an initial EA for the cystic component of the PCTN and subsequent treatment for the remaining solid component, if needed. All 25 patients underwent EA for the cystic component of a PCTN and showed complete collapse of the cystic component on the follow-up US. Twenty patients were subsequently treated with one or more EA sessions because of the presence of a vascularized solid component, whereas 5 patients underwent no additional EA sessions because no vascularized solid component was detected on follow-up US. Of the 20 patients who underwent additional EA for a remaining solid component, complete ablation (n = 9), incomplete ablation (n = 7), and no response (n = 4) were observed on follow-up US. Of the 7 patients with incomplete ablation despite repeated EA, only 4 underwent radiofrequency ablation, and they showed complete ablation on follow-up US. Two-stage EA may be useful for the treatment of benign PCTNs.

Advances in nonsurgical treatment of benign thyroid nodules.

Ethanol ablation has traditionally been used for treatment of cystic thyroid nodules. Laser ablation and radiofrequency ablation were introduced later and used for treatment of solid thyroid nodules. However, how to select the best treatment modality among the different techniques has, so far, not been determined and causes confusion in clinical practice. Therefore, the necessity for a proper guideline regarding the choice of the preferable treatment modality has been suggested as the use of nonsurgical treatment for benign thyroid nodules has been increasing. This article provides an up-to-date review of nonsurgical treatment of benign thyroid nodules focusing on how to select the best treatment modality according to the composition of thyroid nodules based on the clinical evidence.

Efficacy Assessment of Newly Developed Open-Window Intervention Needles for the Treatment of Cystic Thyroid Nodules That Cannot Be Aspirated

The purpose of this study was to develop a novel open-window needle aspiration method and evaluate its efficacy in drainage and sclerotherapy of cystic thyroid nodules that cannot be aspirated with an 18-gauge needle. Two rectangular windows 5.0 mm in length and 1.0 mm wide were placed at the end of the percutaneous transhepatic cholangiography (PTCA) needle trocar to develop a new open-window intervention needle. The efficiency of the open-window intervention needle was compared either to a porous interventional needle or to an ordinary PTCA needle by assessing the aspiration efficiency. The efficacy of the modified open-window approach was tested by carrying out sclerotherapy and drainage on 21 thyroid cystic nodules that could not be aspirated with an 18-gauge needle and comparing it to aspiration with an 18-gauge PTCA needle of 50 cystic thyroid nodules. The efficacy of aspirating coupling agents of various specifications using the new open-window intervention was superior to aspiration using the PTCA trocar needle or a porous needle (p<0.05). Ethanol ablation efficacy in the treatment of 21 cystic thyroid nodules that could not be aspirated with an 18-gauge needle and the aspiration efficacy of 50 cystic thyroid nodules with an 18-gauge PTCA needle were not significantly different (p>0.05). The new open-window intervention needle approach was highly effective in conducting ethanol ablation of cystic thyroid nodules that could not be aspirated using conventional methodologies.

Risk prediction model of malignant partially cystic thyroid nodules

Objective A multivariate logistic regression model was built to estimate the risk of malignant partially cystic thyroid nodules.Methods Data of ultrasonographic morphology,microcalcifications,margin,colloid crystals and echogenicity of 766 thyroid nodules (of 506 patients) were analyzed retrospectively.All patients underwent surgery and the diagnosis were confirmed by pathology.The model was built to calculate the individual risk and evaluate the predictive index.Results The regression model was Z =-2.30 + 1.42X2 + 2.39X3 + 1.17X4-1.35 X7 + 0.62X9 ; P =eZ/1 + ez (P represents probability of malignancy,e represents natural constant 2.72).The largest area under the receiver-operating characteristics curve (AUC) was 0.86.When apply the model to the verification group(266 nodules),the accuracy,sensitivity,specificity,misdiagnosis rate,missed diagnosis rate,negative likelihood ratio and positive likelihood ratio were 93.61％,83.33％,94.63％,5.37％,16.67％、0.18 and 15.52 respectively.Conclusions This model based on the ultrasonographic variables increases the diagnostic accuracy of malignancy in patients with partially cystic thyroid nodules. Key words: Ultrasonography; Thyroid nodule; Logistic models

Intralesional saline injection for effective ultrasound-guided aspiration of benign viscous cystic thyroid nodules.

Purpose:We aimed to evaluate the efficacy and safety of vigorous saline injection for viscous cystic thyroid nodules.Methods:Eighteen patients who underwent ultrasound-guided aspiration for viscous cystic thyroid nodules using a saline injection were included in our study. After failing to aspirate the cyst by the usual method, we vigorously injected saline into the cyst in multiple directions to break up and liquefy the viscous cystic contents to enable aspiration. The initial and the residual volume of the nodule were calculated, and the volume reduction rate and the time taken to perform the aspiration were recorded.Results:The mean volume of the cystic nodules before aspiration was 11.0 mL (range, 1.2 to 26.0 mL), while the postaspiration volume was 4.2 mL (range, 0.2 to 14.5 mL). The mean aspirated volume was 63.7% of the initial volume. The mean procedure time was 12.4 minutes (range, 5 to 26 minutes). There were no significant complications related to the procedure. Conclusion:A vigorous saline injection followed by aspiration can be a useful method to aspirate viscous cystic thyroid nodules as a prestep for further intervention or simple management.

Percutaneous ethanol ablation in managing predominantly cystic thyroid nodules: An eastern India perspective.

Aims:Percutaneous aspiration and ethanol injection (PEI) is effective in managing predominantly cystic (>50% cystic) thyroid nodules with efficacy ranging from 38-85%. We aimed to evaluate efficacy, safety, and factors determining outcomes of PEI in managing simple cystic (purely cystic) vs. complex cystic (having both cystic and solid components) thyroid nodules.Materials and Methods:Predominantly cystic thyroid nodules, without any ultrasonography and/or fine needle aspiration, evidence of malignancy were aspirated ultrasonography guided. Sterile 100% ethanol (50-100% volume aspirated) was injected and reviewed monthly for 3 months and thereafter 3 monthly. Responders were defined as ≥ 50% reduction in nodule volume.Results:Sixty-five patients out of 152 considered underwent PEI. Sixty patients [simple cystic (42) and complex cystic (18)] with mean follow-up of 12.3 ± 2.88 months were analyzed. Response rate of PEI was 78.33% [simple cystic (92.86%) and complex cystic (44.44%) nodules; P < 0.001]. Also, 31.67% patients achieved remission at 1st month. And, 46.67% patients achieved remission between 1-6-months follow-up. Kaplan Meier analysis showed significantly improved outcomes in patients with simple cystic nodules (P < 0.001). Cox-regression revealed type of nodule (simple cystic vs. complex cystic) to be predictive of outcome (P = 0.034). Complex cystic nodules were 67.6% less likely to go into remission, compared to simple cystic nodules. Baseline nodule size, aspirate, or volume of ethanol injected did not predict outcome.Conclusions:PEI is safe and should be treatment of choice for simple cystic thyroid nodules. PEI for complex cystic thyroid nodules are associated with lower response, increased recurrence, and need for repeated PEI.

Characteristics of thyroid nodules in infant with congenital hypothyroidism

PurposeThis study aimed to assess the characteristics of thyroid nodules among infants diagnosed with congenital hypothyroidism.MethodsA retrospective study of 660 infants (374 males, 286 females) diagnosed with congenital hypothyroidism was carried out at the Pediatric Endocrine Clinic in Soonchunhyang University Hospital, Korea, between May 2003 and February 2013. The average age at diagnosis was 1.16±1.68 months.ResultsOf the 28 patients (4.2%) with thyroid nodules, 17 (2.6%) had cystic thyroid nodules and 11 (1.6%) had solid thyroid nodules. There were no significant differences in gender or age between congenital hypothyroidism patients who hadthyroid nodules and those who did not. All nodules were asymptomatic. The average age at diagnosis of congenital hypothyroidism with nodules was 1.42±1.39 months. All detected nodules measured less than 1 cm in diameter. Twenty-two of the 28 infants (78.6%) had only one nodule, while multiple nodules were found in 6 infants (21.4%). Of the 28 infants diagnosed with nodules, 16 underwent thyroid ultrasonography during follow-up and 8 of them (50%) showed no signs of nodules at thyroid ultrasonography.ConclusionThe prevalence of thyroid nodules in infants with congenital hypothyroidism was 4.2%. Most thyroid nodules were small in size and benign, disappearing during follow-up observation. We therefore conclude that thyroid nodules in infants with congenital hypothyroidism can simply be observed and do not require direct treatment.

A Case of Primary Hyperparathyroidism due to Intrathyroidal Parathyroid Cyst.

Parathyroid cysts constitute 0.08–3.41% of all parathyroid masses. Intrathyroidal parathyroid cysts, however, are rare conditions with only a few cases being reported. Most of the parathyroid cysts are found to be nonfunctional and functional cysts are generally thought to be due to cystic degeneration of parathyroid adenomas. A cystic, smooth contoured lesion of 24 × 19 × 16 mm was observed in left thyroid lobe of a 76-year-old woman during ultrasonography which was performed as routine workup for primary hyperparathyroidism. It was defined as a cystic thyroid nodule at first. Tc99m sestamibi scintigraphy was performed to see any parathyroid lesions, but no radioactive uptake was observed. Intact parathormone (iPTH) level was found to be >600 pg/mL in cyst aspiration fluid. Left lobectomy was performed, with a diagnosis of primary hyperparathyroidism due to functional parathyroid cyst. Serum iPTH level was decreased >50% postoperatively and histopathological evaluation was consistent with an encapsulated parathyroid adenoma with a cystic center. Parathyroid cysts are among rare causes of primary hyperparathyroidism. Diagnosis is made by markedly increased iPTH level in cyst fluid and observation of parathyroid epithelium lining the cyst wall.

Minimally invasive surgery colloidal cystic thyroid nodules

An analysis of the use of minimally invasive interventions - laser-induced thermotherapy (LITT), ethanol destruction (ED) under ultrasound guidance, a combination of these methods in the treatment of сystic-col- loidal nodes (CCN) of thyroid nodules in 120 patients. ED carried out in 31 patients with cystic destruction of a site of more than 70%. Marked decrease in the average volume with 4.68 ± 2.25 cm3 to 1.15 ± 0.9 cm3. In 4 patients remained cystic cavity of small size, which required a combination of LITT (CombiLITT). Nine patients underwent LITT solid residue of more than 1 cm3. The average size of nodules within 6 months after the primary surgery was 0.9 ± 0.3 cm3. СombiLITT performed in 42 patients with cystic cavity from 20 to 70%. The volume of units decreased from 7.98 ± 4.56 to 1.87 ± 0.9 cm3. After 3 months, 11 patients with the size of a solid residue of more than 1 cm3 held LITT. All of them when viewed after 3 months observed decrease of more than 50%. LITT performed 23 patients with major nodes and cystic cavities less than 20% of the node. Marked decrease in the amount of nodes with 2.89 ± 1.25 cm3 to 1.42 ± 0.8 cm3. Retesting LITT took 2 patients. After 6 months, the average amount of units was 0.7 ± 0.2 cm3 LITT conducted in 24 patients with small cystic nodes to 1 cm3. Marked decrease in size from 0.69 ± 0.23 cm3 to 0.29 ± 0.12 cm3. Varied selection of minimally inva- sive treatment of CCN is effective and in most cases, to achieve reduction of the size of nodes.

Tiroid kistlerine perkütan etanol enjeksiyonu

Objective: To present the results of 28 patients who were treated by Doppler ultrasound guided percutaneous ethanol injection (PEI) into benign cystic thyroid nodules. Methods: Before percutaneous injection of ethanol, malignancies were excluded with fine needle aspiration biopsy. Volume of the nodule was calculated according to length χ width χ depth χ π/6 formula. During the application, 95% ethanol solution was injected about half of the initial cystic volume. At follow-up nodule diameter, formation of fibrosclerosis and nodule vascularization were evaluated. More than 50% reduction in nodule volume relative to the initial volume was defined success. Results: The success rate with single application of PEI was found 88.5 percent. With administration of the second application of PEI on unsuccessful cases success rate increased to 92.9 percent. Conclusion: Doppler ultrasound-guided PEI injection is a reliable, effective and inexpensive method in the treatment of thyroid cysts with high success rates.

Combination Therapy Consisting of Ethanol and Radiofrequency Ablation for Predominantly Cystic Thyroid Nodules

Predominantly cystic thyroid nodules are often aspirated before radiofrequency ablation to enhance its efficacy; however internal bleeding during the aspiration is a problem. We evaluated the feasibility and safety of ethanol ablation to control internal bleeding that occurred during preparatory aspiration. Between September 2010 and August 2011, 11 of 40 predominantly cystic nodules bled internally during fluid aspiration before radiofrequency ablation. To control the bleeding, 99% ethanol was injected. The efficacy of ethanol in controlling bleeding, final nodule volume and complications were assessed. Control of the bleeding by ethanol ablation and subsequent radiofrequency ablation was feasible in all patients. Ninety-one percent (10/11) could be treated in 1 session. The mean nodule volume dropped from 17.1 to 4.3 mL (P < .018). There were no major complications. Ethanol ablation and radiofrequency ablation combination therapy is a feasible and safe technique for treating predominantly cystic thyroid nodules that exhibit internal bleeding during preparatory aspiration.

Ethanol ablation of benign thyroid cysts and predominantly cystic thyroid nodules: factors that predict outcome

No study has so far investigated the relationship between aspirate color or degree of aspiration on the success of ethanol ablation (EA) of cystic thyroid nodules. We aimed to evaluate the efficacy of EA of benign cystic thyroid nodules and assess the relevant factors influencing the outcome. Over a 2-year period, 64 benign cystic thyroid nodules in 62 patients were treated with EA. Several factors related to EA efficacy were evaluated, including the cystic component volume, volume and color of aspirates, degree of aspiration, and volume of injected ethanol. In all cases, we performed ultrasound follow-up for at least 12 months after the last EA session to evaluate the collapsed cystic component. The 64 treated nodules had aspirate colors that were red bloody (n = 3), dark bloody (n = 31), brownish (n = 15), greenish-yellow (n = 13), and colorless (n = 2). The degrees of aspiration were scant (n = 8), mild (n = 3), moderate (n = 8), and complete (n = 45). There was successful collapse of the cystic component after initial EA in 52 cases, but a repeat EA was employed in 12 failed cases. Statistical analysis showed that the degree of aspiration and color of aspirates correlated significantly with the success of EA. The results of this study suggest that complete aspiration of cystic contents was the most important factor in the efficacy of EA of benign cystic thyroid nodules, and greenish-yellow contents were closely related to scant or mild aspiration.

Novel mechanisms of tube-size regulation revealed by the Drosophila trachea

The size of various tubes within tubular organs such as the lung, vascular system and kidney must be finely tuned for the optimal delivery of gases, nutrients, waste and cells within the entire organism. Aberrant tube sizes lead to devastating human illnesses, such as polycystic kidney disease, fibrocystic breast disease, pancreatic cystic neoplasm and thyroid nodules. However, the underlying mechanisms that are responsible for tube-size regulation have yet to be fully understood. Therefore, no effective treatments are available for disorders caused by tube-size defects. Recently, the Drosophila tracheal system has emerged as an excellent in vivo model to explore the fundamental mechanisms of tube-size regulation. Here, we discuss the role of the apical luminal matrix, cell polarity and signaling pathways in regulating tube size in Drosophila trachea. Previous studies of the Drosophila tracheal system have provided general insights into epithelial tube morphogenesis. Mechanisms that regulate tube size in Drosophila trachea could be well conserved in mammalian tubular organs. This knowledge should greatly aid our understanding of tubular organogenesis in vertebrates and potentially lead to new avenues for the treatment of human disease caused by tube-size defects.

Interstitial Laser Photocoagulation (ILP) of Benign Cystic Thyroid Nodules—A Prospective Randomized Trial

Recurrence rate, after aspiration, in cystic thyroid nodules is very high. Interstitial laser photocoagulation (ILP) is a minimally invasive procedure that reduces the need for surgery in patients with a benign solid thyroid nodule. The aim of the study was to evaluate the efficacy of ILP on remission rates in recurrent, predominantly cystic thyroid nodules. Forty-four consecutive outpatients with a symptomatic, recurrent, and cytologically benign cystic (cyst volume ≥ 2 mL) thyroid nodule were randomized to a single aspiration with (n = 22) or without (n = 22) subsequent ILP and followed up after 1, 3, and 6 months. Successful outcome (cyst volume ≤ 1 mL) was obtained in 15 of 22 (68%) patients in the ILP group, compared to 4 of 22 (18%) in the aspiration group (P = .002). In the ILP group, the solid part of the nodule was reduced from a median of 1.8 to 1.0 mL (P = .02). In the aspiration-alone group, neither the cyst volume nor the solid nodule volume was significantly reduced. The reduction in median visual analog score (0-10 cm) for pressure symptoms was significantly higher in the ILP group (from 3.0 to 0.0 cm) than in the aspiration-alone group (from 4.0 to 3.5 cm) (P = .006, between groups). No major side effects occurred, and thyroid function was unaffected throughout. US-guided aspiration and subsequent ILP of benign recurrent predominantly cystic thyroid nodules is safe. It significantly reduces recurrence rate, the volume of the solid nodule component, and pressure symptoms. ILP constitutes an important alternative to surgery in such patients.

Single-Session Treatment of Benign Cystic Thyroid Nodules with Ethanol versus Radiofrequency Ablation: A Prospective Randomized Study

To compare volume reduction of single-session ethanol ablation (EA) and radiofrequency (RF) ablation for cystic thyroid nodule treatment. All patients gave written informed consent to participate in this prospective institutional review board-approved study. From May 6, 2010, to August 8, 2011, in this single-institutional, noninferiority trial, 50 patients, each with a single cystic thyroid nodule, were randomly assigned to EA (25 patients; mean age for women, 45.7 years, and for men, 37.5 years) or RF ablation (25 patients; mean age for women, 45.1 years, and for men, 43.7 years) treatment. Internal fluid was aspirated prior to EA or RF ablation. Primary end point was the volume reduction ratio (percentage) at 6-month follow-up; the noninferiority margin was chosen as -8% (EA minus RF ablation). Secondary end points included therapeutic success rate, improvement of symptoms and cosmetic problems, and number of major complications. Analysis was performed primarily in intention-to-treat manner. A one-sided 95% confidence interval (CI) for the mean difference in volume reduction ratio 6 months after treatment was calculated to test for noninferiority. Subsequent superiority comparison of EA with RF ablation on a condition of establishment of the noninferiority of EA to RF ablation was preplanned and used two-sided 95% CI of the outcome difference. The mean volume reduction was 96.9% in EA and 93.3% in RF ablation (n = 21 for each) (difference, 3.6%; lower bound of the one-sided 95% CI of the difference, 1.2%), thus demonstrating the noninferiority of EA to RF ablation. Two-sided 95% CI of the outcome difference was 0.7% to 6.5%, demonstrating significant superiority of EA to RF ablation. All patients demonstrated therapeutic success (P > .99). Mean symptom and cosmetic scores showed no significant difference in either group (P = .806 and P = .682, respectively). There were no major complications (P > .99). EA may be the first-line treatment modality for cystic thyroid nodules, which has comparable therapeutic efficacy to, but is less expensive than, RF ablation.

Ultrasound-guided fine-needle aspiration of benign thyroid cysts or partially cystic thyroid nodules: a preliminary study for factors predicting successful collapse

No published study has evaluated factors that predict successful collapse of the cystic component of benign cystic thyroid nodules after ultrasound (US)-guided fine-needle aspiration (US-FNA). This study aimed to assess the collapse rate of the cystic component of benign cystic thyroid nodules after US-FNA and to evaluate the factors related to successful collapse of cystic component. Over a 2-year period, US-FNAs of fluid from the cystic components of 97 thyroid nodules with measured volume of >1 mL were performed, and for 80 nodules at least 1 follow-up US exam was performed. Each thyroid nodule was classified according to the largest diameter, percentage of cystic component, volume and colors of aspirate, degree of aspiration, and the time to the last US follow-up. The rate of complete collapse of the cystic component was 18.8 % (15/80). The success rate increased as the degree of aspiration increased (p = 0.0328), and there was a statistically significant difference between bloody and non-bloody aspirates (p = 0.0019). The time to the last US follow-up had statistically significant correlation with complete collapse rate (p < 0.0001), but largest diameter of thyroid nodule, percentage of cystic component, and volume of aspirate showed no significant correlation. Only 32 nodules were reexamined by US after more than 3 months, of which 11 showed complete collapse (34.4 %). In this study, rates of successful collapse of the cystic component after US-FNA of benign cystic thyroid nodules were higher in cases of complete aspiration and in those with bloody aspirates.

Conventional Ultrasonography and Real Time Ultrasound Elastography in the Differential Diagnosis of Degenerating Cystic Thyroid Nodules Mimicking Malignancy and Papillary Thyroid Carcinomas

To evaluate the diagnostic utility of conventional ultrasonography and real time ultrasound elastography in differentiating degenerating cystic thyroid nodules mimicking malignancy from papillary thyroid carcinoma. We retrospectively analyzed conventional ultrasonographic and elastographic characteristics of 19 degenerating cystic thyroid nodules mimicking malignancy in 19 patients, with 30 surgically confirmed PTCs as controls. Based on size, the nodules had been grouped into less than 10mm (group A) and greater than 10 mm (group B). We evaluated conventional parameters and elasticity pattern. Color-scaled elastograms were graded as to stiffness of nodules using an elasticity pattern from I (soft) to IV (stiff). Degenerating cystic thyroid nodules were similar to PTCs in conventional ultrasonographic findings, but the former frequently showed oval to round in shape (group A, 69.2% vs 18.8%, P=0.017; group B, 66.7% vs 7.14%, P=0.017) and punctuate hyperechoic foci (group A, 61.5% vs 0, P<0.001; group B, 50% vs 0, P<0.001). On real time ultrasound elastography, 7 of 13 degenerating cystic thyroid nodules in group A were pattern I, 5 were pattern II, 1 was pattern III. One degenerating cystic thyroid nodule in group B was pattern II, 5 were pattern III. The area under the curve for elastography was 0.98 in group A (sensitivity 92.3%, specificity 100%, P = 0.002), and 0.88 in group B (sensitivity 16.7%, specificity 100%, P = 0.014). As a dependable imaging technique, elastography helps increase the performance in differential diagnosis of degenerating cystic thyroid nodule and malignancy.

The Effect of Ethanol Ablation for the Treatment of Benign Cystic Thyroid Nodules

Simple aspiration is the initial therapy in patients with the symptomatic benign thyroid cystic nodule, but treatment failure is very common. In patients with recurrent cystic thyroid nodules, ethanol ablation (EA), radiofrequency ablation, or laser ablation can be used to prevent reaccumulation of cystic fluid. EA is simple, cheap and needs no specialized equipment. Kim et al. reported the long-term efficacy and safety of ultrasound-guided percutaneous EA for cystic or predominantly cystic thyroid nodules. They also evaluated the clinical factors associated with treatment failure. Successful ablation was obtained in 31 of 40 (77.5%) patients, and initial large cystic volume was the factor associated with therapeutic failure. The side effect was negligible except transient local pain immediately after the procedure. Although this study had retrospective design and irregular follow-up, it is plausible that EA is a safe and effective therapy for treating cystic or predominantly cystic thyroid nodule. (Korean J Med 2013;85:589-591)

甲状腺・頸部&amp;#22218;胞性疾患に対する経皮的エタノール注入術

甲状腺囊胞などの頸部囊胞性疾患に対し経皮的エタノール注入術（Percutaneous Ethanol Injection Therapy，PEIT）を施行し，その効果について報告する。2005年より2012年までに当科でPEITを施行した症例は13例であった。男性4例，女性9例で年齢は33歳から95歳，平均55歳であった。臨床診断は甲状腺囊胞が11例，頸部リンパ管腫が2例であった。PEIT前の囊胞の大きさは体積換算で3mLから160mLで平均44mL，PEITは1回から4回，中央値で1回施行し，施行後22%から100%，平均89%縮小した。PEITの合併症は針抜去時の局所痛以外に認められなかった。甲状腺囊胞や頸部リンパ管腫に対するPEITは治療効果と合併症の頻度の点で有用な治療法であると考えられた。