Recommendations for management of cystic thyroid disease

Comparison of the effectiveness of lauromacrogol injection for ablation and microwave ablation in the treatment of predominantly cystic thyroid nodules: a multicentre study

PURPOSE

To compare the therapeutic efficacy and safety of microwave ablation (MWA) and lauromacrogol injection for ablation (LIA) for benign predominantly cystic thyroid nodules.

MATERIALS AND METHODS

In this retrospective study, 85 patients with predominantly cystic thyroid nodules (PCTNs) who underwent microwave ablation (MWA) or lauromacrogol injection for ablation (LIA) between June 2019 and August 2022 at three hospitals were included in our research. Forty-six patients were treated with microwave ablation, and thirty-nine patients were treated with lauromacrogol injection for ablation. The baseline characteristics, nodal volume, volume reduction rate (VRR), and incidence of postoperative complications were compared between these two groups.

RESULTS

After treatment, there were significant differences in the thyroid nodule volume and the volume reduction rate (VRR) at different follow-up times between the groups (p < 0.001). There were no significant differences in the nodal volume or the volume reduction rate (VRR) between the MWA group and the LIA group at 1, 3, 6, and 12 months (p > 0.05). Of note, no serious intraoperative or postoperative complications occurred in the corresponding group.

CONCLUSION

MWA and LIA are very effective and safe strategies for the treatment of predominantly cystic thyroid nodules. However, LIA is more advantageous in that it is less expensive and has a shorter length of hospital stay than MWA.

Ultrasound grayscale ratio: a reliable parameter for differentiating between papillary thyroid microcarcinoma and micronodular goiter

BACKGROUND

The present study aimed to quantify and differentiate the echo levels of papillary thyroid microcarcinomas (PTMCs) and micronodular goiters (MNGs) using the ultrasound grayscale ratio (UGSR) and to investigate the repeatability of UGSR.

METHODS

The ultrasound (US) data of 241 patients with 265 PTMCs and 141 patients with 168 MNGs confirmed by surgery and pathology were retrospectively analyzed. All patients had received outpatient ultrasonic examination and preoperative ultrasonic positioning. The RADinfo radiograph reading system was used to measure the grayscales of PTMC, MNG, and thyroid tissues at the same gain level, and the UGSR values of the PTMC, MNG, and thyroid tissue were calculated. The patients were divided into outpatient examination, preoperative positioning, and mean value groups, and the receiver operating characteristic (ROC) curves were calculated to obtain the optimal UGSR threshold to distinguish PTMC from MNG. The interclass correlation coefficient (ICC) was used to assess the consistency of UGSR measured in three groups.

RESULTS

The UGSR values of the PTMC and MNG were 0.56 ± 0.14 and 0.80 ± 0.19 (t = 5.84, P < 0.001) in the outpatient examination group, 0.55 ± 0.14 and 0.80 ± 0.19 (t = 18.74, P < 0.001) in the preoperative positioning group, and 0.56 ± 0.12 and 0.80 ± 0.18 (t = 16.49, P < 0.001) in the mean value group. The areas under the ROC curves in the three groups were 0.860, 0.856, and 0.875, respectively. When the UGSR values for the outpatient examination, preoperative positioning, and mean value groups were 0.649, 0.646, and 0.657, respectively, each group obtained its largest Youden index. A reliable UGSR value was obtained between the outpatient examination and preoperative positioning groups (ICC = 0.79, P = 0.68).

CONCLUSION

UGSR is a simple and repeatable method to distinguish PTMC from MNG, and hence, can be widely applicable.

Not All Bethesda 1 Thyroid Nodules Were Created Equal: Different B1 Subgroups

OBJECTIVE

The Bethesda System for Reporting Thyroid Cytopathology is a uniform method used worldwide to report thyroid fine-needle aspiration (FNA) outcomes. This study focuses on the Nondiagnostic/Unsatisfactory category, designated as Bethesda1 (B1). The documented risk of malignancy for B1 nodules can vary significantly, implying this category is not homogenous and might be composed of different subtypes. Our hypothesis was that B1 subgroups (blood only, insufficient thyrocytes, cyst content) will vary in their malignancy rate.

METHODS

The study design was observational and retrospective. The study population included 154 patients in the Galilee Medical Center who underwent FNA examination of the thyroid gland from 2013-2018 and had a B1 result. We looked at the final diagnosis of malignant or benign for patients who underwent surgery and calculated the malignancy rate for each subgroup.

RESULTS

Malignancy rates were higher in the Blood subgroup than in the other subgroups, and higher in the Thyrocytes subgroup than in the Cyst subgroup (P < .05). All malignancies were papillary thyroid carcinomas. There was no significant difference in the malignancy rate when we further divided the B1 samples into 2 groups based on the presence of epithelial cells. Many repeat FNA tests resulted in a different B1 subgroup.

CONCLUSION

The different malignancy rates suggest that individual management approaches should be considered for each B1 subgroup.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Sequential treatment by polidocanol and radiofrequency ablation of large benign partially cystic thyroid nodules with solid components: Efficacy and safety

PURPOSE

The purpose of this study was to retrospectively evaluate the efficacy and safety of a sequential treatment including percutaneous polidocanol sclerotherapy and radiofrequency ablation (RFA) in terms of volume reduction and complication rate in large, benign, partially cystic thyroid nodules with solid components.

MATERIALS AND METHOD

From April 2017 to April 2019, 46 patients with 47 large benign partially cystic thyroid nodules underwent sequential treatment. There were 14 men and 32 women with a mean age of 49.9±11.5 (SD) years (range: 18-75 years). The volume of initial nodules was 12.7±12.3 (SD) mL (range: 2.16-75.62mL). Volume reduction after percutaneous polidocanol sclerotherapy and further RFA was evaluated respectively. Patients had clinical and ultrasound evaluations at a follow-up time of 12.1±5.3 (SD) months (range: 1.5-23.9 months). Technical success and complications were accessed retrospectively.

RESULTS

After unsatisfying results with polidocanol sclerotherapy alone the 46 patients with 47 large benign partially cystic thyroid nodules had further RFA. Mean volume reduction of 47 nodules was 90.5±11.3 (SD) % (range: 43.9-99.3%) one month after RFA, 94.9±6.2 (SD) % (range: 66.9-99.5%) three months after RFA, and 95.8±5.5 (SD) % (range: 71.0-99.8%) six months after RFA. No recurrence or nodule enlargement after RFA was observed at the last follow-up. The complication rate of RFA was 12.5% (8/46 patients), with minor complications only.

CONCLUSIONS

The sequential treatment regimen, including percutaneous polidocanol sclerotherapy and RFA, is an appropriate and safe treatment strategy for large benign partially cystic thyroid nodules with solid components.

Non-functional thyroid cystadenoma in three boxer dogs

Background

Thyroid neoplasia is a common endocrine neoplasm in dogs. The boxer is one of the reported breeds predisposed to malignant thyroid neoplasia. However, the association between thyroid neoplasia, malignancy and breed should be considered with caution.

Cases presentation

This article describes the presentation, clinical pathological findings, computed tomographic (CT) imaging findings and histopathological features of benign cystic thyroid tumour (cystadenoma) diagnosed in three boxers. These three dogs were presented for investigation of unilateral (n = 2) or bilateral (n = 1) cervical masses with no associated clinical signs of thyroid dysfunction. In each case, post-contrast CT scan identified a large, lateralised, non-invasive, well-defined homogeneous cystic structure with a hyperattenuating contrast-enhancing capsule of suspected thyroid origin displacing the surrounding cervical tissues. Ultrasound-guided fine needle aspiration of the cysts yielded fluid with a high thyroxine concentration in each case. Histopathology was consistent with thyroid cystadenoma in all cases. One dog was concurrently diagnosed with oral melanoma and euthanased. Two dogs underwent surgical excision with one lost to follow-up after 36 months and the other euthanased after 16 months following diagnosis of mast cell tumour.

Conclusions

To the authors’ knowledge, this is the first detailed report of non-functional benign thyroid cystadenoma in dogs and provides relevant information about case management for this type of tumour. The presence of a large cystic structure associated with benign non-functional thyroid neoplasia may be a condition to which boxer dogs are predisposed.

Thyroid FNAC: Causes of false-positive results

In this paper, we aim to focus on false positive results in the evaluation of thyroid aspirations, covering cystic, inflammatory, follicular and oncocytic lesions, papillary carcinoma, and medullary carcinoma of thyroid. The recently described entity noninvasive follicular thyroid neoplasm with papillary-like nuclear features is also discussed detailing the impact of its introduction on the sensitivity and specificity of thyroid FNA, as well as the use of molecular tests for diagnostics. Medicolegal issues in relation to current practice in English law are also described.

Comparison of Ultrasound-Guided Percutaneous Polidocanol Injection Versus Percutaneous Ethanol Injection for Treatment of Benign Cystic Thyroid Nodules

OBJECTIVES

We compared the efficacy, safety, and cost-effectiveness of ultrasound-guided percutaneous polidocanol injection and percutaneous ethanol injection for the treatment of benign cystic and predominantly cystic thyroid nodules.

METHODS

A total of 135 cystic thyroid nodules treated by percutaneous ethanol injection and 136 cystic thyroid nodules treated by percutaneous polidocanol injection were enrolled retrospectively in this study from May 2010 to March 2016. The nodules were followed after 1, 3, 6, and 12 months. Nodule volumes, symptoms scores, and cosmetic scores were assessed before treatment and at follow-up. The therapeutic success rate, safety, and cost-effectiveness between the groups were also compared.

RESULTS

No significant differences in the reduction of the nodule volume, volume reduction rate, and therapeutic success were observed between the groups with cystic and predominantly cystic thyroid nodules during follow-up (P > .05). Neither the cosmetic scores (P = .59; P = .42) nor the symptom scores (P = .32; P = .73) in the cystic and predominantly cystic nodules were significantly different between the groups at the last follow-up. The complication rates for ethanol were higher than those for polidocanol (P < .05). However, the cost of polidocanol injection was higher than that of ethanol injection for cystic thyroid nodules (mean ± SD, US$97.18 ± US$22.17 versus US$43.36 ± US$5.51; P < .01).

CONCLUSIONS

Ultrasound-guided percutaneous polidocanol injection can be an alternative for sclerotherapy of cystic or predominantly cystic thyroid nodules. However, its cost was higher than that of percutaneous ethanol injection.

Partially cystic thyroid nodules in ultrasound-guided fine needle aspiration: Prevalence of thyroid carcinoma and ultrasound features

Partially cystic thyroid nodules (PCTNs) are common on ultrasound (US). However, there are insufficient data on the prevalence of thyroid carcinoma among such nodules. The purpose of this study was thus to evaluate the prevalence and differentiation of partially cystic thyroid cancers in US-guided fine needle aspiration (FNA).A total of 1342 consecutive patients with 1360 thyroid nodules underwent prospective US diagnosis and FNA biopsy. In total, 281 nodules (20.7%) were partially cystic lesions. The nodules were prospectively analyzed based on US features (ie, solid portion positions, shapes, margins, and microcalcifications) and US diagnosis (benign, suspicious, or malignant).Of the 281 partially cystic lesions, 22 nodules (8%) had inadequate FNA results, 14 nodules were diagnosed as malignant, 9 were suspicious for malignancy, and 236 were benign on FNA. Thirteen cancers were confirmed upon surgical histopathology examination or FNA, yielding a 4.6% rate of malignancy. Twelve of these cancers were papillary carcinomas, and 1 was an anaplastic carcinoma. The following individual sonographic characteristics had a statistically significant association with thyroid cancer: nodule composition (solid portion ≥50%, P = .000), eccentric solid portion (P = .001), irregular nodule shape (P = .000), microcalcification (P = .000), and intranodular vascularity (P = .001). The sensitivity, specificity, and accuracy of the US-based diagnoses were 84.6%, 84.0%, and 84.0%, respectively.Fewer than 5% of the partially cystic nodules in this FNA series were malignant. Sonographic characteristics can be used to prioritize nodules for FNA biopsy.

Reappraisal of "cyst fluid only" on thyroid fine-needle aspiration cytology

According to the Bethesda System for Reporting Thyroid Cytopathology (BSRTC), cyst fluid only (CFO) cases are classified in the non-diagnostic category. To date, no large study focusing on CFO has been conducted. To reassess the diagnostic significance of CFO, we compared CFO nodules with non-diagnostic nodules excluding CFO (ND-other). We reviewed the conventional thyroid smears of 715 CFO and 766 ND-other nodules. We compared the timing of and findings at re-aspiration, the histology of resected specimens, and the proportion of malignant nodules between the two groups. Re-aspiration was performed in 9.0% of CFO and 23.8% of ND-other cases. In 12.5% of CFO and 49.4% of ND-other cases, the interval between the first and second aspirations was <3 months. Despite this, there were no cases in which cytological interpretation was complicated by the first aspiration. Overall, 77 CFO nodules (10.8%) were surgically resected; 14 were malignant. In all cases in which re-aspiration cytology revealed malignancy, the initial ultrasound interpretation was a high or intermediate suspicion pattern. The proportion of malignancies subsequently diagnosed in nodules initially classified as CFO and ND-other was 2.0% and 5.6%, respectively (p<0.01). As CFO and ND-other thyroid nodules have different clinical management and malignancy rates, we would like to assert that CFO and ND-other nodules should be separated, and that the former should be considered diagnostic. In terms of clinical management, we recommend that only CFO cases with concerning features on ultrasound undergo re-aspiration.

Efficacy and safety of ultrasound-guided percutaneous polidocanol sclerotherapy in benign predominantly cystic thyroid nodules: a prospective study

OBJECTIVE

To evaluate the efficacy and safety of percutaneous polidocanol injection (PPI) in treatment of predominantly cystic thyroid nodules.

MATERIALS AND METHODS

This prospective study included 111 patients with 122 benign predominantly cystic thyroid nodules inducing pressure symptoms or cosmetic problems. The nodules were randomized to a single aspiration with (n = 61) or without (n = 61) subsequent PPI and followed up after 1, 3, 6, and 12 months. Ten patients (12 nodules) declined to follow up after aspiration in group 2. Nodule volumes, symptoms scores, and cosmetic scores were evaluated before and after treatment. The therapeutic success rate and safety of PPI for treatment of predominantly cystic thyroid nodules were also evaluated.

RESULTS

In the PPI group, the nodule volumes were reduced from 13.67 ± 9.90 to 2.60 ± 2.66 (p < .001). Therapeutic success rate (nodule volume reduction >50%) was obtained in 57 of 61 (93.44%) nodules in the PPI group, compared to seven of 49 (14.29%) in the aspiration group (p < .001). In the aspiration group, the nodule volume was not significantly reduced. The reduction in symptom scores was significantly higher in the PPI group (from 3.60 ± 1.65 to 1.60 ± 1.19) than in the aspiration group (from 3.62 ± 1.89 to 3.30 ± 1.06) (p < .001, between groups). The reduction in cosmetic scores showed a significant difference between groups (p < .001). In total, 4.92% of patients (3/61) in the PPI group and 85.71% (42/49) in the aspiration group showed recurrence during the follow-up period. There was a significant difference in the recurrence rate between groups (p < .001). No major side-effects occurred.

CONCLUSIONS

US-guided PPI of benign recurrent predominantly cystic thyroid nodules is effective and safe. PPI is an important alternative to benign recurrent predominantly cystic thyroid nodules.

Efficacy and Safety of Ultrasound-Guided Percutaneous Polidocanol Sclerotherapy in Benign Cystic Thyroid Nodules: Preliminary Results

OBJECTIVE

To evaluate the efficacy and safety of percutaneous polidocanol injection (PPI) in treating cystic thyroid nodules.

MATERIALS AND METHODS

A total of 158 cystic or predominantly cystic thyroid nodules (>80% cystic component) in 143 patients were evaluated. 114 patients with compressive symptoms or aesthetic complaints were offered PPI. 44 individuals without compressive symptoms and aesthetic complaints who were only followed up clinically were used as the control group. The efficacy and safety of PPI were evaluated for 1 month, 3 months, 6 months, 9 months, and 12 months of follow-up.

RESULTS

In the PPI group, the mean baseline volume of 15.6 ± 18.9 cm³ reduced at the 1-month follow-up to 5.1 ± 5.6 cm³ (p < 0.001) and 0.6 ± 0.9 (p < 0.001), and nodules shrunk according to the time after PPI (p < 0.001). A complete response (if ≥70% decrease) to PPI at the 12-month follow-up occurred in 100% of the cystic or predominant cystic nodules. None of the nodules recurred at the 12-month follow-up after PPI. The side effects were mild. Twenty patients (17.5%) developed mild localized pain, and fourteen cases (12.3%) experienced mild or moderate fever after PPI.

CONCLUSIONS

PPI is a safe and effective alternative to treat benign cystic or predominant cystic thyroid nodules.

Predictive factors for occult contralateral carcinoma in patients with unilateral papillary thyroid microcarcinoma by preoperative ultrasonographic and pathological features

BACKGROUND

The surgical extent and indication for treatment in patients with papillary thyroid microcarcinoma (PTMC) remain a controversial issue. The aim of this study was to investigate the predictive factor for contralateral occult carcinoma in patients with unilateral PTMC by preoperative ultrasonographic and pathological features.

METHODS

Of the total patients who underwent thyroidectomy, 455 patients with PTMC confined to one unilateral lobe as diagnosed using preoperative ultrasonography (US) were enrolled in the study. Occult contralateral carcinoma was defined as tumor foci in the contralateral lobe that was not detected preoperatively, but was detected pathologically. All patients underwent preoperative US review to investigate the US features of PTMC such as laterality, location, size, internal component, echogenicity, margin, calcification shape, multifocality, bilaterality, extrathyroidal extension, and location with respect to the trachea. Clinicopathological data were also analyzed.

RESULTS

Of the total of 455 patients who underwent total thyroidectomy for preoperatively detected unilateral PTMC, 71 patients (15.6 %) had contralateral occult carcinoma. Clinicopathological characteristics did not significantly differ between patients with and without contralateral occult carcinoma. Multivariate analysis showed that the absence of a well-defined margin and the presence of a probably benign nodule in the contralateral lobe were independent predictive factors for contralateral occult carcinoma in patients with unilateral PTMC in preoperative US images.

CONCLUSION

We demonstrated that an absence of a well-defined margin and the presence of a probably benign nodule in the contralateral lobe were independent predictive factors for contralateral occult carcinoma in patients with unilateral PTMC in preoperative US. The prediction of contralateral occult carcinoma in unilateral PTMC using preoperative US features could be useful for determining the optical extent of surgery.

Differential profile of ultrasound findings associated with malignancy in mixed and solid thyroid nodules in an elderly female population

Objective. Ultrasonographic characteristics are associated with thyroid malignancy. Our aim was to compare the diagnostic value of ultrasound features in the detection of thyroid malignancy in both solid and mixed nodules. Methods. We prospectively studied female patients (≥50 years) referred to ultrasound-guided fine needle aspiration biopsy. Ultrasound features considered suspicious were hypoechogenicity, microcalcifications, irregular margins, high anteroposterior (AP)/axial-ratio, and absent halo. Associations were separately assessed in mixed and solid nodules. Results. In a group of 504 elderly female patients (age = 69 ± 8 years), the frequency of malignant cytology was 6%. Thirty-one percent of nodules were mixed and 60% were solid. The rate of malignant cytology was similar for mixed and solid nodules (7.4 versus 5.8%, P: 0.56). While in mixed nodules none of the ultrasound characteristics were associated with malignant cytology, in solid nodules irregular margins and microcalcifications were significant (all P < 0.05). The combination of irregular margins and/or microcalcifications significantly increased the association with malignant cytology only in solid nodules (OR: 2.76 (95% CI: 1.25–6.10), P: 0.012). Conclusions. Ultrasound features were of poor diagnostic value in mixed nodules, which harbored malignant lesions as often as solid nodules. Our findings challenge the recommended minimal size for ultrasound-guided fine needle aspiration biopsy in mixed nodules.

Characteristics of thyroid nodules in infant with congenital hypothyroidism

Purpose

This study aimed to assess the characteristics of thyroid nodules among infants diagnosed with congenital hypothyroidism.

Methods

A 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.

Results

Of 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.

Conclusion

The 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.

Role of cytological characteristics of benign thyroid nodules on effectiveness of their treatment with levothyroxine

INTRODUCTION

Levothyroxine (LT4) therapy has been used for the treatment of euthyroid nodular goiter, but there are controversial results about its usefulness. We aimed to evaluate the possible role of benign nodules' cytological characteristics in response to LT4 therapy.

MATERIAL AND METHODS

In total, 93 patients with 128 nodules were included in the study; 74 of the nodules were treated with LT4 (group 1), and 54 of them had no medication (group 2). The subgroups consisted of adenomatous nodules, colloid nodules and cystic nodules.

RESULTS

In group 1, mean thyroid volume and mean nodule volume were reduced significantly (p = 0.002 and p = 0.022, respectively) with low-normal level thyrotropin (TSH) suppression (between 0.3 mIU/ml and 1.0 mIU/ml), while there were no significant changes in group 2. When we evaluated changes of the initial and last nodule volumes in cytological subgroups, only colloid nodules in group 1 had significant reduction (p = 0.040) and the others had no significant changes. By omitting the colloid nodules, when the other nodules were revaluated, there were no significant changes in either group.

CONCLUSIONS

On the basis of these results, obtained from a large sample of Anatolian patients, it is possible that LT4 therapy leads to significant reductions of both thyroid volume and nodule size in colloid nodules, but not in other kinds of benign nodules.

Partially cystic thyroid nodules: ultrasound findings of malignancy

Objective

To seek for the ultrasound (US) findings of partially cystic thyroid nodules that are associated with malignancy.

Materials and Methods

We reviewed the US characteristics of 22 surgically confirmed partially cystic papillary carcinomas, and compared them with those of 80 benign partially cystic nodules. The review cases were selected in a random order from a total of 1029 partially cystic nodules that were diagnosed with an US-guided fine needle aspiration biopsy over a period of 8 years (June 2003 to October 2010) at our institution.

Results

In partially cystic thyroid nodules, a taller-than-wide shape (100%, p < 0.001) and spiculated or microlobulated margin (58.3%, p = 0.003) were significantly associated with malignancy. In terms of internal solid portion of the nodule, eccentric configuration (68.0%, p < 0.001), non-smooth margin (81.3%, p < 0.001), hypoechogenecity (30.0%, p < 0.042), and microcalcification (89.5%, p < 0.001) were more frequently demonstrated in malignant nodules than benign ones.

Conclusion

In partially cystic thyroid nodules, understanding the characteristics of US findings is important to make a precise diagnosis of malignant nodules.

Mixed echoic thyroid nodules on ultrasound: approach to management

PURPOSE

To evaluate malignancy risk according to ultrasound (US) features and size change on follow-up US in mixed echoic thyroid nodules and to suggest management guidelines thereof.

MATERIALS AND METHODS

Among patients who underwent US-guided fine needle aspiration biopsy, 316 mixed echoic nodules in 303 patients were included after excluding the patients with pure solid or cystic nodules or without further cytopathologic evaluation. We evaluated malignancy risk according to US features and changes in size and shape on follow-up US.

RESULTS

The malignancy rate was 31.6% (6 of 19) for nodules with suspicious US features and 2.7% (8 of 297) for nodules without suspicious US features (p<0.001). Among 265 nodules with no suspicious US features and initial benign cytology, 15 nodules with suspicious US change and decreased size, 25 nodules with no suspicious US change and increased size, and 225 nodules with no suspicious US change and no change in size were observed on follow-up USs. The malignancy risk thereof was 0%, 0% and 0.4%, respectively (p=1.000).

CONCLUSION

Mixed echoic nodules with no suspicious US features and benign cytology can be followed up using US, as they revealed very low malignancy rates, even if they showed growth on follow-up US.

Thyroid nodules: risk stratification for malignancy with ultrasound and guided biopsy

Replacing palpating fingers with an ultrasound (US) probe has resulted in an epidemic of thyroid nodules. Despite the high prevalence of thyroid nodules in the general population, thyroid malignancy is rare. Although no imaging modality can accurately predict the nature of every nodule, high-resolution US is the most sensitive, easily available and cost-effective diagnostic test available to detect thyroid nodules, measure their dimensions and identify their structure. The presence of calcifications, irregular spiculated outline, hypoechogenicity in a solid nodule, chaotic intranodular vascularity and an elongated shape are well-known US features of malignancy in thyroid nodules. Cervical lymph node metastasis and extrathyroidal extension of a thyroid nodule are highly specific for malignancy but seen infrequently. Spongiform nodules, purely or predominantly cystic nodules, nodules with well-defined hypoechoic halo and echogenic as well as isoechoic nodules are usually benign. None of the US characteristics have 100% accuracy in detecting or excluding malignancy. Fine-needle biopsy is currently the best triage test for pre-operative evaluation of a thyroid nodule. There is no significant difference in the risk for malignancy between palpable and non-palpable nodules and size is not a reliable indicator for their malignant potential. The best tool for risk stratification for malignancy in thyroid nodules is US and guided biopsy of nodules with suspicious imaging features. This is especially relevant in patients with multinodular goitre.

Efficacy and safety of USG-guided ethanol sclerotherapy in cystic thyroid nodules

OBJECTIVE

To study the effectiveness and safety of USG-guided ethanol sclerotherapy in cystic thyroid nodules.

MATERIALS AND METHODS

USG of the thyroid gland was performed in 54 patients suspected to have a thyroid nodule on clinical examination. All patients with a predominantly cystic nodule (i.e., when> 2/3 rd of the nodule was cystic) were included in the study. Ethanol was injected into the cyst under USG guidance. The amount of ethanol injected was about 50% of the amount of aspirated fluid. Follow-up USG was done every month for 3 months; ethanol was re-injected when there was no significant reduction in the cyst volume. The initial cyst volume was compared with the final volume; statistical significance was assessed using the paired t-test.

RESULTS

USG revealed predominant cystic nodules in 16 of the 54 patients. Fifteen patients were selected for the study. Following ethanol sclerotherapy, four out of the 15 patients (26.6%) showed complete disappearance of the cyst and nine (60%) showed significant reduction in the cyst volume (i.e., reduction of cyst volume by >/=50% of initial volume). Only two patients did not show significant reduction in cyst volume; both these patients had nodules with an initial volume of >/=20 cc. There were no complications attributable to ethanol injection during follow-up.

CONCLUSION

Ethanol sclerotherapy is an effective and safe treatment for benign cystic thyroid nodules with volumes of < 20 cc. Cystic nodules with volume> 20 cc may need more number of alcohol injections and longer follow-up.

Comparison of ultrasound-guided biopsy technique for thyroid nodules with respect to adequacy of cytological material

BACKGROUND

Ultrasound-guided fine-needle aspiration cytology (FNAC) sampling of the thyroid represents a standard diagnostic procedure in the evaluation of thyroid nodules. The specimen can be acquired using either of two different techniques. In the first, the short axis is used with observation only of the tip of the needle whilst in the nodule. In the second technique, the long axis is used with the observation of the entire length of the needle. The decision to sample utilizing either technique was done randomly. This study is a retrospective review performed to compare these two techniques with regard to specimen adequacy.

METHODS

Ultrasound-guided FNACs were performed in 80 thyroid nodules between May 2008 and February 2009. One physician acquired the cytology specimens using one of these two methods after localization. Data on the type of technique and its diagnostic accuracy were collected.

RESULTS

Forty-nine of 80 thyroid nodules were sampled using the long-axis technique. The overall and deep-lesion diagnostic adequacies of specimens were significantly higher using this technique (93.9 and 95.1%, respectively, p < 0.01) than the short-axis technique. When comparing the long and short axes for superficial lesions, there was no significant difference in adequacy of the samples (p = 0.92).

CONCLUSIONS

This is the first study to compare long- and short-axis techniques with regard to specimen adequacy for thyroid nodules. The long-axis technique decreased the rate of inadequate material and provided more accurate cytological evaluation for deeper lesions.

Sonographic differentiation of partially cystic thyroid nodules: a prospective study

BACKGROUND AND PURPOSE

There is no prospective study related to the sonographic differentiation of malignant PCTN from benign PCTN. This prospective study was designed to evaluate differentiation of benign from malignant PCTNs with thyroid sonography.

MATERIALS AND METHODS

Two hundred thirteen PCTNs in 196 patients who had consecutively undergone prospective sonographic diagnosis and US-FNAB were included. The PCTNs were evaluated according to their configuration and the presence of calcification, a free margin, vascularity, spongiform appearance or daughter cysts, colloid crystal, nodule shape, and echogenicity. Each PCTN was prospectively classified into 1 of 4 diagnostic categories: benign features, probably benign, suspicious for malignancy, and malignant features. We calculated the diagnostic efficacy of a prospective sonographic diagnosis for PCTNs by comparing it with cytopathologic results.

RESULTS

Among the 213 PCTNs, 53 underwent thyroid surgery. The sonographic classifications for 213 PCTNs included benign features (n = 182), probably benign (n = 19), suspicious for malignancy (n = 7), and malignant features (n = 5). When nonsurgical PCTNs (n = 160) with benign sonographic findings and benign cytology were considered negative, the sensitivity, specificity, PPV, NPV, and accuracy of the prospective diagnosis of PCTNs were 72.7%, 98.0%, 66.7%, 98.5%, and 96.7%, respectively. On the basis of individual analysis, eccentric configuration with an acute angle and microcalcifications were significantly associated with malignancy, but a concentric configuration, a smooth free margin, peripheral vascularity, spongiform appearance or daughter cysts, and intranodular colloid crystals showed a statistically significant association with benignity.

CONCLUSIONS

Our prospective sonographic diagnoses of PCTNs, especially those >2 cm, were highly reliable.

Partially cystic thyroid nodules on ultrasound: probability of malignancy and sonographic differentiation

BACKGROUND

Thyroid nodules are very common and a large portion are mixed echoic, with both solid and cystic areas. There are few studies regarding the reliability of ultrasonographic criteria for evaluating solid nodules as they apply to mixed echoic nodules. The object of this study was to evaluate the frequency of malignancy in mixed echoic thyroid nodules and ascertain the ultrasound findings that help distinguish benign from malignant nodules.

METHODS

Among 1056 thyroid nodules undergoing ultrasound with fine-needle aspiration (FNA) biopsy, 392 nodules (37.1%) were mixed echoic. From this group of 392, the nodules that were read as benign or malignant on histopathology examination after surgery and the nodules that were not resected but were considered to be benign or malignant on cytology were analyzed for their ultrasonographic features. The nodules were divided into the following three groups. Group 1 (n = 93) included nodules in which the solid portion was <50%; group 2 (n = 216) comprised nodules in which the solid portion was >or=50%; and group 3 (n = 26) included mixed echoic (spongy) nodules. We also analyzed features of the solid portion of the nodule, namely, its position (eccentric or not), shape, margin, and echogenicity, and whether there were micro/macrocalcifications.

RESULTS

In the FNA sample, 52 nodules were inadequate for cytological diagnosis, but the remaining 340 (86.7%) were adequate. Eighteen of the nodules were malignant and 317 were benign, yielding a malignancy rate of 5.4%. By group, the malignancy rate was 2.2% (2/93) in group 1, 7.4% (16/216) in group 2, and 0% (0/26) in group 3. There were more malignancies in group 2 than the other groups (p = 0.040). Among sonographic findings, eccentric placement (p = 0.007) and the presence of microcalcifications (p < 0.001) were significantly correlated with malignancy.

CONCLUSIONS

About 5% of partially cystic nodules in our series were malignant. When more than 50% of the nodule is solid and the solid portion of the nodule is eccentric, the risk of malignancy is greater. As has been noted for completely solid nodules, microcalcifications are associated with an increased risk of malignancy.

Feasibility, Accuracy, and Clinical Relevance of a Rapid Thyroid Evaluation During Carotid Duplex Ultrasonography in Hypertensive Patients

Carotid ultrasonography can detect thyroid nodules without increasing examination duration. The authors analyzed whether management is influenced by reporting such findings during routine carotid ultrasonography in hypertensive patients vs waiting for 6 months to repeat them. This is a population-based study of 1216 hypertensive patients. During carotid ultrasonography, nodule cystic/solid characteristics and size of thyroid changes were recorded. Patients with nodules were divided into those with nodules reported at the moment of diagnosis (group A) and those reported 6 months after diagnosis (group B). The authors monitored patients who underwent thyroid treatment 12 months after carotid ultrasonography. A total of 255 participants had thyroid nodules detected on screening and 99 patients started therapy after discovery. Six months later, as expected, there were more patients undergoing thyroid treatment in the group with nodules reported at time of diagnosis. This difference between groups was not significant, however, 6 months after reporting the nodules, in group B, because the number of patients on therapy significantly increased. Thyroid nodules cannot be ignored during carotid ultrasonography, and reporting their presence is valuable to general practitioners. Thyroid screening during carotid ultrasonography is cost-effective, rapid, sensitive, and specific and may affect the patient's diagnostic and therapeutic management.

Evaluation of the thyroid nodule

BACKGROUND

Thyroid nodules are common, yet treatment modalities range from observation to surgical resection. Because thyroid nodules are frequently found incidentally during routine physical examination or imaging performed for another reason, physicians from a diverse range of specialties encounter thyroid nodules. Clinical decision making depends on proper evaluation of the thyroid nodule.

METHODS

The current literature was reviewed and synthesized.

RESULTS

Current evidence allows the formulation of recommendations and a general algorithm for evaluating the incidental thyroid nodule.

CONCLUSIONS

Only a small percentage of thyroid nodules require surgical management. Diagnosis and treatment selection require a risk stratification by history, physical examination, and ancillary tests. Nodules causing airway compression or those at high risk for carcinoma should prompt evaluation for surgical treatment. In nodules larger than 1 cm, fine-needle aspiration biopsy is central to the evaluation as it is accurate, low risk, and cost effective. Subcentimeter nodules, often found incidentally on imaging obtained for another purpose, can usually be evaluated by ultrasonography. Other laboratory and imaging evaluations have specific and more limited roles. An algorithm for the evaluation of the thyroid nodule is presented.

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.

[Approach to cytologically-benign recurrent thyroid cysts]

INTRODUCTION

The aim of this study was to determine the incidence of carcinoma in cytologically-benign recurrent thyroid cysts and to evaluate the surgical indications in these patients.

PATIENTS AND METHOD

We reviewed all patients undergoing thyroid surgery between January 1992 and December 2002 for cytologically-benign solitary or dominant cystic nodules in multinodular goiter that recurred after aspiration. Mixed nodules were excluded.

RESULTS

Thirty-four patients (29 women and five men) with a mean age of 43 years (18-76) underwent surgery. Seventy-five percent were solitary nodules and 25% were dominant nodules within a multinodular goiter. The mean number of fine needle aspirations with complete drainage was 2.3 (2-3) per patient with hemorrhagic aspirate in 35%. Total thyroidectomy was performed in multinodular goiters and lobectomy with isthmectomy in solitary nodules. Intraoperative biopsy revealed benign lesions in 91% and was inconclusive in the remainder; no cases of carcinoma were identified. Definitive pathologic findings revealed the nodule to be a papillary carcinoma in 3 patients (8.8%) and occult papillary carcinoma separate from the cyst in 4 patients (11.8%). In all these patients intraoperative biopsy showed benign disease. The risk of malignancy was higher in cysts larger than 3 cm (23% vs 0%; p<0.05).

CONCLUSIONS

Given the incidence of carcinoma, surgical resection should be considered in recurrent cystic thyroid nodules, especially in those larger than 3 cm, regardless cytological study.

Detection of Thyroid Carcinoma in Wall of a Cystic Lesion by FDG PET

PURPOSE

Three cases are described, in which positron emission tomography (PET) led to the diagnosis of carcinoma in solitary thyroid nodules (STN), which were considered benign by clinical assessment, ultrasonography, and fine needle aspiration cytology (FNAC).

MATERIALS AND METHODS

These 3 cases were from a group of 51 patients with solitary thyroid nodules that were nonfunctioning or "cold" on pertechnetate scans that were later studied with FDG PET scanning.

RESULTS

Of the entire group, 28 patients showed the nodule to be nonfunctioning on FDG scans. Of these, 3 showed one or more small foci of intense FDG uptake in the periphery. On histopathology, these sites were found to harbor carcinoma, papillary carcinoma in 2 patients and a follicular variant of papillary carcinoma in one.

CONCLUSIONS

These cases demonstrate the usefulness of FDG PET in detection of cancer that may lurk in the wall of a cystic thyroid nodule, often misinterpreted as benign by conventional methods.

Modified percutaneous ethanol injection in the treatment of viscous cystic thyroid nodules

Here we describe a prospective 2-year evaluation of the efficiency of a new procedure of percutaneous ethanol injection (PEI) treatment of viscous thyroid cystic nodules (VTCN). Three patients with VCTN were selected from a group of 22 patients with solitary thyroid cystic nodules. A modified two-stage ethanol injection procedure was planned for these patients. Stage 1 was performed through the injection of a small dose of ethanol into the nodule. The viscosity of the content was reduced within 2 weeks after the injection. In the second stage the nodule was decompressed and an established dose of sterile 95% ethanol was injected. Patients were followed up for 2 years. In all cases a reduction in nodule volume was found. In the following 18 months further reduction was observed, with an average of 91.7%. The effect was stable throughout the follow-up period. No complications were observed. Therefore, our new two-stage PEI procedure appears all efficient alternative approach for the treatment of VCTNs even if further investigations on a larger series are required.

Recommendations for the management of cystic thyroid nodules

BACKGROUND

The management of cystic thyroid nodules has not been standardized with respect to an initial fine-needle aspiration cytology (FNAC) cystic change result, which is defined as fluid aspiration and a smear with numerous macrophages but scant or no follicular cells. In the present study the physical characteristics of cystic thyroid nodules predictive of the pathology were investigated, and recommendations made on their management.

METHODS

The aspiration results of 1436 thyroid nodules managed between 1998 and 2000 were investigated. A total of 157 patients who had a subsequent operation or follow-up data with reaspiration were the subjects of the present study. Age, sex, nodule characteristics and others were examined as possible predictors of cancer risk.

RESULTS

The malignancy rate was 8.9%. Ten cases (71%) of malignancy were not cytologically diagnosed. Male sex and a nodule size of > or = 4 cm were found to be statistically significant predictors of malignancy. The malignancy rate was highest (100%) when a cystic lesion had malignant cytology on reaspiration and local invasion on radiology.

CONCLUSIONS

When a cystic change is observed by initial FNAC of thyroid nodules, nodules of > or = 4 cm must be reaspirated and a firm cytologic diagnosis made to rule out malignancy. Nodules should be considered for surgery having taken into account other characteristics, in particular male sex and radiologic findings of local invasion.

Ultrasound scan-guided core sampling for diagnosis versus freehand FNAC of the thyroid gland

BACKGROUND AND AIM

Freehand fine needle aspiration cytology (FNAC) is an obligatory investigation of the thyroid nodule. Between 5.0-43.1% of FNAC samples are reported as being initially unsatisfactory. In our unit, thyroid freehand FNAs are performed with a small needle (21 or 23G). Non-dominant nodules as part of multinodular goitres, difficult to palpate nodules or nodules with previously unsatisfactory freehand FNACs are sampled under ultrasound scan (USS) guidance with the larger 20G cutting core sampling technique. We aimed to compare the satisfactory sampling rate and safety of the two different methods.

PATIENTS AND METHODS

Cytology forms were reviewed for 262 freehand FNACs and USS-guided core samples, performed in our unit over a two-year interval (1 July 1999 to 30 June 2001).

RESULTS

Ultrasound-guided core samples for cytology were unsatisfactory (AC0-1) in 19/121 (15.6%) of the cases, compared with 66/141 (46.8%) of freehand FNACs (p value = < 0.0001). Ten out of eleven patients (91%) had a satisfactory USS-guided core after an unsatisfactory freehand FNA; 7/15 patients (46.7%) had satisfactory repeat freehand FNACs following an initial unsatisfactory freehand FNAC (p value = 0.0191). There were no complications as a result of either freehand FNAC or USS-guided core sampling.

CONCLUSION

USS-guided cores provided more satisfactory samples for assessment than freehand FNACs. The USS-guided technique is safe despite the use of the larger cuffing needle. The USS-guided core sampling was also a useful tool for repeat thyroid nodule sampling after an unsatisfactory freehand FNAC.

Management of cystic or predominantly cystic thyroid nodules: the role of ultrasound-guided fine-needle aspiration biopsy

OBJECTIVE

Conventional fine-needle aspiration biopsy (FNAB) for cystic thyroid nodules (CTNs) has a high rate of nondiagnostic and false-negative results. Ultrasound-guided FNAB (UG-FNAB) permits direct sampling of the wall and/or the solid portion of CTNs, increasing the possibility of a representative sample. In this study we evaluated the role of UG-FNAB in CTNs management.

METHODS

Five-hundred-seventy-five UG-FNAB of CTNs were performed. Thyroidectomy was carried out in 119 of these cases. The medical records of these 119 patients were reviewed and form the basis of this report.

RESULTS

The nondiagnostic smear rate was 9.2%. Cytological diagnosis was benign nodule in 42 cases, predominantly follicular lesion in 50 cases, and suspicious or malignant lesion in 16 cases. The final pathology revealed a benign nodule in 98 cases (82.4%) and a carcinoma in 21 (17.6%). The overall accuracy of UG-FNAB was 88.0%. No significant differences were found in age, sex, lesion size, or echographic pattern (p = NS) comparing patients with benign CTNs to patients with malignant CTNs.

CONCLUSION

UG-FNAB has a low rate of nondiagnostic smears and a high overall accuracy in CTNs. All CTNs should undergo UG-FNAB to select patients for surgery, since the malignancy rate is not negligible and no clinical parameter can reliably predict it.

Treatment of recurrent thyroid cysts with ethanol: a randomized double-blind controlled trial

Thyroid nodules are prevalent; when evaluated by ultrasonography (US), 15-25% of solitary thyroid nodules are cystic or predominantly cystic, and most are benign. Simple aspiration is the treatment of choice, but the recurrence rate is 10-80% depending on the number of aspirations and the cyst volume. The aim of this study was to evaluate the effect on recurrence rate of benign recurrent thyroid cysts in a double-blind randomized study comparing ethanol instillation with instillation of isotonic saline and subsequent complete emptying. Sixty-six consecutive patients with recurrent and benign (based on US-guided biopsy) thyroid cysts (>or=2 ml) were randomly assigned to either subtotal cyst aspiration, flushing with 99% ethanol, and subsequent complete fluid aspiration (n = 33), or to subtotal cyst aspiration, flushing with isotonic saline, and subsequent complete fluid aspiration (n = 33). In case of recurrence (defined as cyst volume >1 ml) at the monthly evaluations, the treatment was repeated but limited to a maximum of three treatments. Procedures were US-guided, and patients were followed for 6 months. Age, sex, number of previous aspirations, pretreatment cyst volume, and serum TSH did not differ in the two groups. Cure (defined as a cyst volume <or=1 ml at the end of follow-up) was obtained in 27 of 33 [82%; confidence interval (CI), 65-93] patients treated with ethanol and in 16 of 33 (48%; CI, 31-66) patients treated with saline (P = 0.006). In the ethanol group, 21 of 33 (64%) patients were cured after one session only, compared with six of 33 (18%) in the saline group (P = 0.002). The number of previous aspirations (P = 0.005) and baseline cyst volume (P = 0.005) had influence on outcome, i.e. the chance of success decreased with the number of previous aspirations and with increasing cyst volume. Seven patients (21%) treated with ethanol had moderate to severe pain (median duration, 5 min; CI, 2-10), and one had transient dysphonia. Indirect laryngoscopy was performed before and after the last session and was normal in all patients. We concluded that treatment of recurrent thyroid cysts with ethanol is superior to simple aspiration and flushing with saline and devoid of serious side effects. Our study demonstrates that flushing with ethanol is a clinically significant nonsurgical alternative for thyroid cysts that recur despite repeat aspirations.

Fine needle aspiration in the management of benign thyroid cysts

BACKGROUND

Resolution of cystic thyroid lesions after aspiration occurs in 8-45% of cases, the remainder require treatment for residual tumour or recurrent cysts. The aim of this study was to identify patient characteristics that predict cyst recurrence to enable these patients to undergo early surgery.

METHODS

A retrospective analysis of 123 patients with benign thyroid cysts that were suitable for conservative management was undertaken. Demographic, clinical, ultrasound and fine needle aspiration cytology data were collated for patients who underwent surgery or were managed conservatively. Univariate and multivariate analyses were performed to identify factors predictive of cyst recurrence.

RESULTS

Of the 123 patients, 43 underwent surgery consequent on cyst recurrence or persistent symptoms after aspiration, and 80 were treated by aspiration alone. There were 17 males and 106 females, of mean age 45.5 years. The mean cyst size was 27 mm. Those undergoing surgery had a significantly greater mean cyst size (P = 0.001). The only factor predicting cyst recurrence on univariate analysis was absence of follicular cells on initial aspiration (P = 0.005). Multivariate analysis confirmed absence of follicular cells as an independent characteristic predicting recurrence, the odds ratios for recurrence was 3.18 (95%CI 1.39-7.29).

CONCLUSION

The present study suggests consideration of early surgery for patients with thyroid cysts with absence of follicular cells on initial cytology.

Cystic thyroid and parathyroid lesions in cats

Reports of cystic thyroid and parathyroid masses in cats are uncommon. Herein, the authors describe a series of four cats with cystic ventral cervical lesions, among them thyroid cyst (n=1), thyroid cystadenoma (n=2), and parathyroid adenocarcinoma (n=1). Presentations ranged from completely asymptomatic cervical swellings to signs related to local compression of adjacent structures (e.g., trachea). Ultrasonographic evaluation was helpful in localization of the mass in two cases. Hormone analysis and concentration of cystic fluid were performed in one cat. Surgical excision was performed successfully in three cases. Histopathological examination was performed in all four cases. Long-term prognosis was excellent for those cases in which follow-up was available.

Management of simple nodular goiter: current status and future perspectives

The simple nodular goiter, the etiology of which is multifactorial, encompasses the spectrum from the incidental asymptomatic small solitary nodule to the large intrathoracic goiter, causing pressure symptoms as well as cosmetic complaints. Its management is still the cause of considerable controversy. The mainstay in the diagnostic evaluation is related to functional and morphological characterization with serum TSH and (some kind of) imaging. Because malignancy is just as common in patients with a multinodular goiter as patients with a solitary nodule, we support the increasing use of fine-needle aspiration biopsy (cytology). Most patients need no treatment after malignancy is ruled out. In case of cosmetic or pressure symptoms, the choice in multinodular goiter stands between surgery, which is still the first choice, and radioiodine if uptake is adequate. In addition to surgery, the solitary nodule, whether hot or cold, can be treated with percutaneous ethanol injection therapy. If hot, radioiodine is the therapy of choice. Randomized studies are scarce, and the side effects of nonsurgical therapy are coming into focus. Therefore, the use of the optimum option in the individual patient cannot at present be based on evidence. However, we are of the view that levothyroxine, although widely used, should no longer be recommended routinely for this condition. Within a few years, the introduction of recombinant human TSH and laser therapy may profoundly alter the nonsurgical treatment of simple nodular goiter.

Assessment of nondiagnostic ultrasound-guided fine needle aspirations of thyroid nodules

Thyroid nodules are common. Evaluation of patients with thyroid nodules typically includes fine needle aspiration biopsy (FNA), an approach that has proven to be accurate for the detection of thyroid cancer. Although the majority of biopsies are adequate for a cytological diagnosis, up to 20% will be insufficient or nondiagnostic. Current opinion suggests that such aspirates should be repeated, although no systematic study has investigated the usefulness of this approach, especially when ultrasound guidance is used to direct the initial FNA. We sought to define the predictors and optimal follow-up strategy for initial nondiagnostic ultrasound-guided FNAs of thyroid nodules. Data were collected for all patients at the Brigham and Women's Hospital Thyroid Nodule Clinic between 1995-2000 who underwent ultrasound-guided FNA of a thyroid nodule. All patients with nondiagnostic cytology were advised to return for a repeat ultrasound-guided FNA. Patient age, gender, nodule size, cystic content, solitary vs. multinodular thyroid, and nodule location were documented and evaluated as possible predictors of a nondiagnostic biopsy in a multivariable model. The rate of diagnostic cytology obtained on repeat ultrasound-guided FNA was calculated. A total of 1128 patients with 1458 nodules were biopsied over a 6-yr period. A total of 1269 aspirations (950 patients) were diagnostic, and 189 (178 patients) were nondiagnostic. The cystic content of each nodule was the only significant independent predictor of nondiagnostic cytology (P < 0.001). The fraction of specimens with initial nondiagnostic cytology increased with greater cystic content (P < 0.001 for trend). A diagnostic ultrasound-guided FNA was obtained on the first repeat biopsy in 63% of nodules and was inversely related to increasing cystic content of each nodule (P = 0.03). One hundred and nineteen patients with 127 nodules returned for follow-up as advised, and malignancy was documented in 5%. Despite ultrasound-guided FNA, there remains a significant risk of initial nondiagnostic cytology, largely predicted by the cystic content of each nodule. Repeat aspiration is often successful and should be the standard approach to such nodules, given their risk of malignancy.

The results of ultrasound-guided fine-needle aspiration biopsy for evaluation of nodular thyroid disease

BACKGROUND

The purpose of this study was to determine whether ultrasonography (US) improves the accuracy and reduces the rate of nondiagnostic fine-needle aspiration biopsy (FNAB) of thyroid nodules.

METHODS

A review of 536 consecutive patients evaluated for nodular thyroid disease from 1990 to 2001 was completed to determine the results for US vs palpation-guided FNAB.

RESULTS

FNAB was used to evaluate 458 patients. US-guided FNAB was performed in 66 (12%) patients: 48 with a nonpalpable nodule, 14 with nondiagnostic standard FNAB, and 4 with a palpable nodule. US-guided FNAB was nondiagnostic in 15 (23%) patients. There were no false-positive or false-negative results. Standard FNAB was performed in 407 patients, 57 (14%) of whom had a nondiagnostic result. There were 2 (3%) false-positive and 3 (1.6%) false-negative results. In 14 patients with a nondiagnostic standard FNAB, US-guided FNAB yielded an adequate specimen in 7 (50%). Nodules evaluated by standard FNAB were 4.1 +/- 0.1 cm (mean +/- SEM) in size compared with 2.5 +/- 0.1 cm for nodules evaluated by US-guided FNAB (P <.05).

CONCLUSIONS

US improves the diagnostic yield in selected patients with nondiagnostic standard FNAB. The higher frequency of nondiagnostic US-guided FNAB was related to its selective use in patients with smaller nodules.

The incidence of carcinoma in cytologically benign thyroid cysts

BACKGROUND

The management of cytologically benign thyroid cysts is controversial. Treatment options include observation, chemical sclerosis, and surgery. This study was undertaken to determine the incidence of carcinoma in cytologically benign thyroid cysts that recur after complete aspiration and to determine the indications for surgery in these patients.

METHODS

The medical records of 1189 consecutive patients undergoing thyroid surgery between July 1995 and November 2000 were reviewed. In 34 patients the indication for surgery was a thyroid cyst with benign cytologic findings that refilled at least once after complete aspiration. These patients were selected for further study.

RESULTS

The 26 women and 8 men had a median age of 42 years. Fine-needle aspiration cytology was consistent with a benign cyst in all these cases. Final pathologic findings revealed the nodule to be a papillary carcinoma in 4 patients (12%). In another 4 patients (12%) an incidental microscopic papillary carcinoma, separate from the cyst, was identified on final pathologic findings. In all 4 patients with papillary carcinoma the cyst size was greater than 3 cm (range, 3.4 to 5.0 cm).

CONCLUSIONS

The incidence of malignancy in cytologically benign thyroid cysts that recur after aspiration is high enough to warrant surgical excision, especially if the cyst is greater than 3 cm in size.

Fine-needle aspiration biopsy of the thyroid

The routine use of thyroid FNAB caused profound changes in the management of thyroid nodules. FNAB allows a prompt identification and treatment of thyroid malignancies and avoids unnecessary surgery in patients with benign lesions, improving quality of life in patients with thyroid nodules. Furthermore, FNAB provides guidance for the type of surgery and reduces costs of care. On average, standard FNAB is nondiagnostic in 25% to 40% of cases, which include inadequate specimens and indeterminate (suspicious) diagnoses. In addition, a small percentage of false-negative diagnoses occur, which are unavoidable and raise concern of a late diagnosis of cancer. To minimize the limitations of FNAB, every center should reach and maintain a high standard of expertise in all of the steps of smear preparation and interpretation. Alternative modes of sampling or sample preparation may result in a reduction of nondiagnostic samples and better accuracy. Every center should set up clinical guidelines tailored to their own FNAB results and including the evaluation of clinical data. More work is needed to increase the accuracy of FNAB in suspicious cases. Toward this goal a variety of molecular markers have been evaluated; although none of them are ideal, some are promising. More studies need to be carried out in larger series to further evaluate the accuracy of these markers in identifying specific cancer histotypes within the group of suspicious lesions. It is hoped that, in the near future, the routine use of a combination of these markers will cost-effectively improve the diagnosis of malignant nodules classified as suspicious on traditional cytology. Statistical methods such as bayesian analysis or neural networks can be advantageously used to integrate different relevant information derived from family and personal history, clinical data, cytologic results, and evaluation of molecular markers.