Ultrasound-guided fine-needle aspiration biopsy in the management of thyroid disease

Discrimination of Benign and Malignant Thyroid Nodules through Comparative Analyses of Human Saliva Samples via Metabolomics and Deep-Learning-Guided Label-free SERS

Thyroid nodules are a very common entity. The overall prevalence in the populace is estimated to be around 65-68%, among which a small portion (less than 5%) is malignant (cancerous). Therefore, it is important to discriminate benign thyroid nodules from malignant thyroid nodules. In this study, an equal number of participants with benign and malignant thyroid nodules (N = 10/group) were recruited. Saliva samples were collected from each participant, and SERS spectra were acquired, followed by validation using a metabolomics approach. An additional equal number of patients (N = 40/group) were recruited to construct diagnostic models. The performance of various machine learning (ML) algorithms was assessed using multiple evaluation metrics. Finally, the reliability of the optimal model was tested using blind test data (N = 10/group for benign and malignant thyroid nodules). The results showed a consistent trend between the SERS metabolic profile and the metabolites identified through MS analysis. The Multi-ResNet algorithm was optimal, achieving a 95% accuracy in sample discrimination. Additionally, blind test data sets yielded an overall accuracy of 83%. In summary, the deep-learning-guided SERS technique holds great potential in the accurate discrimination of benign and malignant thyroid nodules via human saliva samples, which facilitates the noninvasive diagnosis of malignant thyroid nodules in clinical settings.

Lateral lymph node metastasis in papillary thyroid microcarcinoma: a study of 5241 follow-up patients

PURPOSE

To investigate the impact of lateral lymph node metastasis in papillary thyroid microcarcinoma (PTMC).

METHODS

5241 PTMC patients with follow-up information were enrolled in the current study. These patients underwent primary surgery in our situation from January 1997 to December 2016. Additionally, a validation cohort consisting of 274 PTMC patients who underwent primary surgery between January 2020 and December 2021 was also included. Univariable and multivariate logistic analyses were conducted to identify the association between clinicopathologic features and lateral lymph node metastasis (LLNM). Kaplan-Meier survival curve analysis was used to calculate the disease-free survival (DFS) rate. The fitting curve was generated to identify the quantitative relationship between central lymph node metastases (CLNM) and LLNM.

RESULTS

Of 5241 PTMC patients, cervical lymph node metastasis was detected in 1494 (28.5%) cases, including 1364 (26.0%) with CLNM only and 130 (2.5%) with LLNM. With a median follow-up time of 60 months (interquartile range [IQR], 44-81), recurrence was detected in 114 patients (2.2%). Multivariate Cox regression analyses showed that LNM was the only independent risk factor for recurrence, with HR values of 3.03 in CLNM and 11.14 in LLNM, respectively. Tumor diameter >0.5 cm (hazard ratio [HR]:1.80), multifocality (HR:2.59), bilaterality (HR:2.13), extrathyroidal invasion (HR:2.13), and CLNM (HR:5.11) were independent risk factors for LLNM. The prevalence of LLNM escalated significantly with increasing number of lymph node involvement in CLNM when stratified by the number of metastatic lymph nodes and trend was observed similarly in the validation cohort. The fitting curve showed that the incidence of LLNM could be as high as 20.7% when the number of CLNM ≥ 5.

CONCLUSIONS

By analyzing a large database with follow-up information, our study provides evidence that LLNM is significantly correlated with tumor recurrence in patients with PTMC. Tumor size (>0.5 cm), multifocality, bilaterality, extrathyroidal extension (ETE) and CLNM are independent risk factors for LLNM.

Usefulness of Ultrasound-Guided Fine-Needle Aspiration Cytology in the Diagnosis of Non-Palpable Small Thyroid Nodules

Aims and background

Diverse and contradictory approaches have been suggested for the management of non-palpable thyroid nodules. The aim of our study was to evaluate the indications and limits of ultrasound-guided fine-needle aspiration cytology (US-FNAC) in non-palpable infracentimetric thyroid nodules.

Methods and study design

From September 2003 to December 2004 we observed 325 patients with non-palpable thyroid nodules. We divided our series into three groups according to the diameter of the lesion in order to verify the effectiveness of US-FNAC for lesions of less than 1 cm.

Results

We assessed the cases with satisfactory and unsatisfactory results in the three groups into which the sample was divided (4 mm to 1 cm; 10.1 mm to 15 mm, and 15.1 mm to 25.5 mm). Our statistical analysis by means of the z-test showed there was no significant (5%) difference in the percentage distribution of the unsatisfactory results in the three groups.

Conclusions

Fine-needle cytology appears to be a useful diagnostic tool also for nodules of less than one cm because the percentage of unsatisfactory results is not related to the size of the nodule.

Diagnostic accuracy of ultrasound-guided fine needle aspiration biopsy for thyroid malignancy: systematic review and meta-analysis

PURPOSE

To systematically appraise and summarize the available evidence about the diagnostic accuracy of ultrasound-guided fine needle aspiration biopsy (USFNA) for thyroid malignancy, and to explore the integration of these estimates with the probability of thyroid malignancy before USFNA.

METHODS

A comprehensive search of multiple databases from each database's inception to August 2014 was performed. Eligible studies included those that evaluated patients with thyroid nodules who underwent USFNA and subsequent evaluation by histopathology or long-term follow-up.

RESULTS

We identified 32 studies at moderate risk of bias evaluating the USFNA diagnostic characteristics for the diagnosis of thyroid malignancy. Results were imprecise and inconsistent across trials. The pooled likelihood ratio (LR) of thyroid malignancy for a benign USFNA result was 0.09 (95 % CI 0.06, 0.14; I (2) = 33 %), whereas the pooled LR for a malignant result was 197 (95 % CI, 68, 569; I (2) = 77 %). In the case of a suspicious for follicular neoplasm result, the pooled LR for malignancy was 0.6 (95 % CI, 0.4, 1.0; I (2) = 84 %) and 8.3 (95 % CI, 3.6, 19.2; I (2) = 89) for a result of suspicious for malignancy.

CONCLUSION

The available evidence regarding the diagnostic accuracy of USFNA warrants only limited confidence due to risk of bias, imprecision, and inconsistency. However, some USFNA results (benign, malignant) are likely very helpful, by significantly changing the pre-test probability of thyroid cancer.

Potential causes for obtaining non-diagnostic results from fine needle aspiration biopsy of thyroid nodules

PURPOSE

The aim of this prospective study was to evaluate factors that could affect the diagnostic result success ratio of fine needle aspiration biopsy of thyroid nodules.

MATERIALS AND METHODS

664 patients and 696 nodules were included in this study. Demographic features of age and gender and nodule features of macrocalcification (MC) and internal content (cystic or solid predominance) were evaluated. All biopsies were performed from 1 cm or larger nodules. Three different size needles were used for comparison (22, 23 and 25 G). The patients in each group had a similar number of nodules with MC, and cystic predominance to obtain comparable results. All procedures were performed by the same radiologist, who had 4 years of experience. Histologically adequate material criteria were identified. All pathological specimens were evaluated as diagnostic or non-diagnostic by the same pathology technician. Chi-square, student's t test and univariate analysis were used for statistical analysis.

RESULTS

There were no statistically significant differences in demographic features and nodule properties from diagnostic results of fine needle aspiration biopsy of thyroid nodules. On the other hand, 23 G needles offered a better potential for obtaining adequate samples with a statistically significant difference.

CONCLUSION

Obtaining adequate material in fine needle aspiration biopsy from thyroid nodules is a challenging issue and the results are controversial. Since we obtained the best ratio with 23 G needles, we recommend interventional radiologists to use 23 G needles as far as possible and not to consider needles thicker needles than 22 G or thinner than 25 G. Nodule features and demographic features did not have an effect on obtaining adequate cytological material.

Thyroid Imaging Reporting and Data System and Ultrasound Elastography: Diagnostic Accuracy as a Tool in Recommending Repeat Fine-Needle Aspiration for Solid Thyroid Nodules with Non-Diagnostic Fine-Needle Aspiration Cytology

The Thyroid Imaging Reporting and Data System (TIRADS) has been found to be accurate in the stratification of malignancy risk, and elastography has been found to have a high negative predictive value in non-diagnostic thyroid nodules. Through assessment of 104 solid non-diagnostic thyroid nodules, this study investigated the role of both in recommending repeat ultrasonography-guided fine-needle aspiration for solid thyroid nodules with non-diagnostic cytology. All nodules were classified by TIRADS (categories 4a, 4b, 4c and 5), and elastography scores were assigned according to the Rago and Asteria criteria. The malignancy risks for TIRADS categories 4a, 4b, 4c and 5 were 12.5%, 25.0%, 25.8% and 16.7%, respectively. Elastography revealed the highest diagnostic performance for TIRADS category 4a, with a sensitivity, specificity, negative predictive value, positive predictive value and accuracy of 100%, 85.7%, 100%, 50% and 87.5% for the Asteria criteria. Observation may be considered for non-diagnostic solid nodules that have no other suspicious ultrasonographic features and are also benign on real-time strain elastography using the Asteria criteria.

Thyroid cancers with benign-looking sonographic features have different lymph node metastatic risk and histologic subtypes according to nodule size

A decision to perform fine needle aspiration (FNA) on thyroid nodules mainly depends on sonographic features. We investigated if lymph node metastasis (LNM) risk differed by tumor size of thyroid cancers without suspicious sonographic features. Three hundred sixty patients with thyroid cancers with benign looking sonographic features were grouped by nodule size on ultrasonography (US) (≤ or >1 cm). The clinicopathologic parameters were compared between the groups. A multivariate analysis was performed to discover the independent factors predicting the presence of LNM. The nodules greater than 10 mm on US (n = 157) demonstrated a larger tumor size on histology (17.9 ± 14.5 vs. 5.6 ± 2.4 mm, P < 0.001), a lower frequency of classical papillary thyroid carcinoma (PTC) (58.6 vs. 87.2 %, P < 0.001), and a higher frequency of follicular variant PTC and follicular thyroid carcinoma (19.7 and 17.8 % vs. 9.4 and 1.5 %, respectively, P < 0.01). In subgroup analysis of 269 patients with classical PTC, the larger nodule size on US was associated with a higher prevalence of LNM (28.3 vs. 14.7 %, P = 0.007). A multivariate analysis revealed that classical PTC, extrathyroidal extension, and the US nodule size >10 mm were independent predictive factors of LNM after adjusting for age, sex, TSH level, and multifocality. Thyroid cancers larger than 10 mm with benign US features are more likely to be nonclassical PTC than those with smaller diameters. The larger ones also have an increased risk of LNM in classical PTC. These cases require a more aggressive approach to FNA.

A systematic review of ultrasound-guided FNA of lesions in the head and neck--focusing on operator, sample inadequacy and presence of on-spot cytology service

The objective of this review is to perform a systematic review of ultrasound-guided fine-needle aspiration (FNA) services for head and neck lesions with assessment of inadequacy rates and related variables such as the presence of immediate cytological assessment. A computer-based systematic search of articles in English language was performed using MEDLINE (1950 to date) from National Health Service evidence healthcare database and PubMed. Full texts of all relevant articles were obtained and scrutinized independently by two authors according to the stated inclusion and exclusion criteria. The primary search identified 932 articles, but only 78 met all the study criteria. The overall inadequacy rate was 9.3%, 16 studies had on-site evaluation by a cytopathologist/specialist clinician with a rate of 6.0%. In seven studies, a cytotechnician was available to either assess the sample or prepare the slides with an average inadequacy rate of 11.4%. In 1 study, the assessment was unclear, but the inadequacy rate for the remaining 54 studies, without immediate assessment, was 10.3%. The rate for the cytopathologist/specialist clinicians was significantly different to no on-site assessment but this was not found for assessment by cytotechnicians. The review suggests that the best results are obtained with a cytopathologist-led FNA service, where the pathologist reviews the specimen immediately, in relation to the clinical context, thereby deciding on adequacy and need for further biopsies. A systematic review looking at ultrasound-guided FNA of head and neck lesions has not been published previously.

Thyroid ultrasonography: pitfalls and techniques

Thyroid ultrasonography (US) plays a key role in the diagnosis and management of thyroid-related diseases. The aim of this article was to illustrate various pitfalls that can occur in utilizing thyroid US and techniques to prevent them. In this article, we present cases demonstrating the common pitfalls associated with US equipment, performance, normal thyroid structures, misinterpretations, and surrounding structures. Knowledge of these areas is essential to avoid misdiagnosis or improper disease management.

Malignancy risk stratification in thyroid nodules with benign results on cytology: combination of thyroid imaging reporting and data system and Bethesda system

BACKGROUND

The indications of repeat fine-needle aspiration (FNA) for thyroid nodules with benign results of the Bethesda system were investigated.

METHODS

A total of 1,398 nodules were classified according to the Thyroid Imaging Reporting and Data System (TIRADS). TIRADS category 3 included nodules without solidity, hypoechogenicity or marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape on ultrasonography (US). Categories 4a, 4b, 4c, and 5 included nodules with one, two, three or four, or five suspicious US features, respectively. The malignancy risks, and odds ratio (OR) with 95 % confidence interval (CI) were calculated. Analyses were performed for all nodules, nodules >10 mm, and nodules ≤10 mm.

RESULTS

Of 1.398 nodules, 43 (3.1 %) were malignanct. The malignancy risks of benign nodules with categories 3, 4a, and 4b were 0.7, 1.2, and 0.7 %, respectively, whereas those for nodules with categories 4c and 5 were 9.8 and 22.2 %, respectively. The ORs of nodules with categories 4c and 5 were 19.4 (95 % CI 5.0-76.2) and 50.6 (95 % CI 10.4-245.0), respectively. In nodules >10 mm, the malignancy risks of categories 4c and 5 were 2.7 and 20 %, respectively, and the ORs were 10.7 (95 % CI 1.2-93.7) and 236.1 (95 % CI 12.6-4426.4), respectively. In nodules ≤ 10 mm, the malignancy risks of categories 4c and 5 were 12.6 and 22.6 %, respectively, and the ORs were 10.1 (95 % CI 1.3-78.0) and 18.9 (95 % CI 2.1-168.9), respectively.

CONCLUSIONS

Repeat US-guided FNA should be considered in benign thyroid nodules with three or more suspicious US features regardless of size.

Thyroid nodule with benign cytology: is clinical follow-up enough?

Objective

In this multicenter study, we investigated the management algorithm for thyroid nodules with benign cytology using US features from data collected from 7 institutions.

Materials and Methods

The institutional review board approved this retrospective study. Data on 700 focal thyroid nodules in 673 consecutive patients were collected from 7 university-affiliated hospitals. This study included nodules that were diagnosed as benign at initial cytologic evaluation and that underwent pathologic or follow-up study. The risk of malignancy was compared according to the US assessments of each institution as well as looking at all the nodules together as a whole.

Results

Of the 700 nodules, 688 (98.3%) were benign and 12 (1.7%) were malignant. If initial cytologic results were benign, the likelihood of the nodule actually being malignant was from 1 to 3%, varying by institution. The likelihood of a cytologically benign nodule with positive US being malignant (4.7%, 8/169) was higher than that of one without positive US (0.8%, 4/531) (P = .002).

Conclusion

Based on our multicenter study, repeat FNA should be performed in thyroid nodules with initial benign cytology showing suspicious US features in order to decrease the number of false negative cases.

The effects of sonographic and demographic features and needle size on obtaining adequate cytological material in sonography-guided fine-needle aspiration biopsy of thyroid nodules

The aim of this study is to investigate the effects of the sonographic characteristics of the nodule, demographic features of patient, and nodule size and needle size used for sampling, on obtaining adequate cytological material (CM) in thyroid fine-needle aspiration biopsy (FNAB). We performed 270 FNAB between September 2010 and June 2012. Size, echogenicity, and localization of all nodules were evaluated by ultrasonography (US) before the biopsy. Nodules were grouped as <1, 1-3, and >3 cm according to their size and as hypoechoic, isoechoic, hyperechoic, or heterogeneous according to their US characteristics. 20-, 22-, and 24-G needles were used for the biopsies. Different sonographic characteristics of the nodules did not affect the needle selection. All specimens were classified as adequate or inadequate CM by a cytopathologist. A total of 270 nodules were biopsied, 184 (68.1 %) specimens were considered as adequate CM and 86 (31.9 %) specimens were considered as inadequate CM. Patient age and the presence of heterogeneous echogenicity were found to have prognostic significance in univariate analysis (p < 0.05). In a multivariate logistic regression model with forward stepwise method, advanced age (p = 0.001, OR = 1.042, 95CI 1.018-1.068) and heterogeneous echogenicity (p = 0.017, OR = 1.955, 95CI 1.129-3.385) remained associated with an increased risk of inadequate CM obtainment after adjustment for other potential confounders (nodule size >3 cm and needle size 20-G usage) and variables found to be statistically significant in univariate analysis. Non-diagnostic FNAB remains a significant problem in the evaluation of thyroid nodules and can be as high as 30 %. Inadequate CM rates for elderly patients and heterogeneous nodules were significantly higher than that for other factors. The nodule size and needle size used for sampling did not affect the adequacy of FNAB.

Prevalence and Prediction for Malignancy of Additional Thyroid Nodules Coexisting with Proven Papillary Thyroid Microcarcinoma

Objective

To investigate the clinical efficacy of ultrasonographic (US) classification of additional thyroid nodules coexisting with proven papillary thyroid microcarcinoma (PTMC).

Study Design

Historical cohort study.

Setting

Tertiary care institution.

Subjects and Methods

In addition to the prevalence of additional thyroid nodules based on an US classification, the diagnostic accuracy and predictive factors for malignancy were assessed in 300 nodules randomly selected from 300 patients with cytologically proven PTMC who underwent total thyroidectomy.

Results

The most common thyroid nodules were “indeterminate nodules,” 68.0%, followed by “probably benign nodules,” 20.7%, and “suspicious malignant nodules,” 11.3%. For indeterminate nodules, the malignancy rate was 16.6% (34/204) with disregard to its location, either on the contralateral (15.1%, 16/106) or ipsilateral side (18.4%, 18/98) of the known PTMC ( P = .53). According to univariate and multivariate analyses of clinical and US findings for predictive variables of malignancy in indeterminate nodules, hypoechogenicity was proven to be the sole predictive factor for malignancy (odds ratio 5.62, 95% CI, 2.29-13.72).

Conclusion

US-based classification of additional thyroid nodules is a useful tool for decision making of the surgical extent in patients with a single PTMC.

Is follow-up BRAF(V600E) mutation analysis helpful in the differential diagnosis of thyroid nodules with negative results on initial analysis?

Background

We evaluated the usefulness of follow-up BRAF^V600E mutation analysis using ultrasonography-guided fine-needle aspiration (US-FNA) in diagnosis of thyroid nodules showing negative BRAFV600E mutation on prior analysis.

Methodology/Principal Finding

A total of 49 patients (men: 6, women: 43, mean age: 50.4 years) with 49 thyroid nodules were included. Patients had undergone initial and follow-up US-FNA and subsequent BRAF^V600E mutation analysis from US-FNA aspirates. All patients had negative results on initial BRAF^V600E mutation analysis. Clinicopathologic findings, US assessment, and BRAF^V600E mutation results were analyzed according to the final pathology. Of the 49 nodules, 12 (24.5%) were malignant and 37 (75.5%) were benign. Seven (58.3%) of the 12 malignant nodules were positive for BRAF^V600E mutation on follow-up, all showing suspicious US features. Initial US-FNA cytology of the 7 nodules were non-diagnostic (n = 2), benign (n = 2), or atypia (n = 3), while follow-up were benign (n = 1), indeterminate (n = 1), suspicious for malignancy (n = 4), and malignancy (n = 1).

Conclusions/Significance

Follow-up BRAF^V600E mutation analysis may be helpful in the diagnosis of selected thyroid nodules negative for BRAF^V600E mutation on initial analysis, which are assessed as suspicious malignant on US, diagnosed as non-diagnostic, benign or atypia on follow-up US-FNA.

Ultrasound-guided fine-needle aspiration biopsy in unselected consecutive patients with thyroid nodules

The objective was to analyze the results of UG-FNAB, performed in unselected consecutive patients with thyroid nodules. Methods. The UG-FNAB records were analyzed in this retrospective study. Indication for biopsy was the presence of at least one nodule detected by ultrasound. Results. 330 patients at mean age ± SD 48.4 ± 11.2 years; women/men = 12.8/1 were analyzed. From the total 596 nodules found 546 (91.6%) were investigated with 1231 punctures (2.3 per nodule and 3.7 per patient). Benign solitary nodules had 42.7%, multinodular goiter (MNG) 44.8%, inconclusive 4.8%, and others 2.1% and malignant nodules 5.5% of the patients (6.6% of solitary and 5.1% of MNG patients). The risk for a separate nodule in MNG to be malignant was 2.7%. Conclusions. UG-FNAB is a safe and reliable diagnostic approach for thyroid nodules. It is the method of choice for hypo- and isoechoic not purely cystic solitary nodules, regardless of the nodule size. In MNG, its positive predictive value and diagnostic accuracy are lower. The final decision for regular US monitoring, UG-FNAB of the dominant nodule, multipuncture UG-FNAB or surgical exploration is one of complex appraisal. We consider UG-FNAB appropriate for most nodules in MNG, according to the above mentioned criteria.

Ultrasonographic characteristics predictive of nondiagnostic results for fine-needle aspiration biopsies of thyroid nodules

The objective of this study was to identify clinical and ultrasonographic (US) characteristics predictive of nondiagnostic results. An experienced radiologist performed an US-guided fine-needle aspiration biopsy (US-FNA) for 1493 thyroid nodules in 1419 patients. Cytological results were classified as nondiagnostic (<6 groups of cells containing more than 10 cells) or diagnostic. The clinical characteristics of patients and the US features of thyroid nodules were compared according to nondiagnostic or diagnostic results. Age and sex were not associated with nondiagnostic results. A cystic portion >50% and hypoechogenicity were independent factors for predicting nondiagnostic results in all nodules (odds ratios [OR] = 2.82 and 1.88, respectively). In 534 nodules with more than 50% of cystic portion, the size of more than 10 mm and in 813 solid nodules, the size of 5 mm or smaller increased the likelihood of nondiagnostic results (ORs = 3.61 and 1.88, respectively).

Predictive factors related to the recurrence at US-guided fine needle aspiration in postoperative patients with differentiated thyroid cancer

OBJECTIVES

The recent American Thyroid Association management guidelines suggest cervical ultrasonography (US) surveillance in patients with differentiated thyroid cancer (DTC). This study was conducted to identify predictive factors that can determine whether subsequent fine needle aspiration guided by ultrasound (US-FNA) is indicated in patients with lesions detected by US after surgery for DTC.

DESIGN

Retrospective analysis at a university-based tertiary hospital.

PATIENTS AND MEASUREMENTS

We reviewed 207 cases of postoperative US-FNA in 180 patients diagnosed with DTC. We examined the relationship between US-FNA histology and clinical factors, imaging abnormalities found by US and with other modalities and pathological staging.

RESULTS

US-FNA recurrence was positive in 56 (27%) cases and negative in 151 (73%) cases. The mean lesion size for FNA was 0·83 cm (range 0·2-2·9 cm). Univariate analysis indicated that tumour recurrence on US-FNA is associated with elevated stimulated thyroglobulin (sTg) levels, with the initial size of the primary tumour, with abnormal US findings, including the ipsilateral site, level III or IV location and extrathyroidal extension, and with other imaging abnormalities. However, multivariate analysis revealed an independent association between recurrence on FNA and suspicious US findings (OR 9·410; 95% CI 3·322-26·654; P<0·001) and elevated serum sTg (OR 5·001; 95% CI 1·067-23·485; P =0·041). Findings on US that were discriminating for recurrent nodules at the thyroidectomy site were abnormalities that were not oval shape or which had an irregular margin. Calcifications or cystic change showed a low sensitivity of 14%.

CONCLUSIONS

US-FNA for diagnosis of recurrence after surgery for DTC may be limited to patients with elevated sTg or with lesions that have specific suspicious US findings.

Malignancy rate in sonographically suspicious thyroid nodules of less than a centimeter in size does not decrease with decreasing size

We evaluated the malignancy and nondiagnostic rates using fine needle aspiration cytology (FNAC) results in thyroid nodules smaller than 1 cm according to the subdivided size. We retrospectively reviewed the medical records of all subjects underwent FNAC from 2003 to 2009 in our hospital, and 2,756 patients of subcentimeter thyroid nodules with one or more suspicious sonographic features and 7,105 with nodule sized 1 cm or more were included. The malignancy rate was higher in those subcentimeter nodules with suspicious sonographic findings than the nodule sized 1cm or more (19.7% vs 7.8%, P < 0.001). We grouped the nodules based on size with mm interval and observed that the malignancy rate did not decrease but the nondiagnostic results increased its size decrement. When we divided the subjects arbitrarily into a 5 mm or smaller and a 6-9 mm sized group, nondiagnostic cytology findings were reported more frequently in the smaller group (24.3% vs 18.1%, P = 0.001), while the rate of "malignant" was similar (18.3% vs 15.5%, P = 0.123) and the rate of "suspicious for malignancy" was higher (6.8% vs 2.9%, P < 0.001). Therefore when we decide to perform FNAC or not in subcentimeter-sized nodules, we should consider sonographic findings and other clinical risk factors but not the nodular size itself.

Enlarged benign-appearing cervical lymph nodes by ultrasonography are associated with increased likelihood of cancer somewhere within the thyroid in patients undergoing thyroid nodule evaluation

BACKGROUND

Benign-appearing cervical lymph nodes (CLN) are easy to assess during an ultrasonography (US) evaluation for a guided fine-needle aspiration biopsy of a suspicious thyroid nodule, but their clinical significance regarding thyroid cancer risk is not known. Non-malignant-appearing nodes may be an indicator of early malignancy in the thyroid. We hypothesize that there is an increased prediction of thyroid cancer when benign-appearing enlarged CLN (ECLN) > 1 cm in any dimension are present during an US evaluation of thyroid nodules.

METHOD

A review of 269 consecutive patients' charts sent for thyroid nodule assessment that underwent thyroidectomy was conducted to compare ECLN, with the presence of thyroid cancer during an ultrasound-guided fine-needle aspiration biopsy of the thyroid nodule. Surgical excision pathology confirmed all abnormal cytology reports.

RESULTS

From the final 265 charts reviewed, 213 had benign thyroid pathology and 52 had thyroid cancer. Sex, number, and size of the biggest thyroid nodule were not different between groups. Patients with cancer were on average 10 years younger and had higher thyroid-stimulating hormone (TSH) values (p < 0.003) as well as a 10-fold increase in enlarged non-malignant-appearing lymph nodes than their peers without cancer. The presence of ECLN had an 82% sensitivity, 90% specificity, and a 68% positive predictive value for thyroid cancer. There was also an 80% negative predictive value when enlarged lymph nodes were not present. In 8 of the 37 (21.6%) patients with malignancy and ECLN, the primary dominant thyroid nodule was negative on cytologic evaluation, but malignancies were confirmed on surgical specimen, in contralateral nodules on the same side as the ECLN. These nodules were mostly subcentimeric, ranging from 0.2 to 1.14 cm and were not biopsied due to their inconspicuous appearance. After multiple logistic regression analysis, enlarged lymph nodes had a 53.8 odds ratio for cancer (20.49-141.33, p < 0.01).

CONCLUSION

Discovering the presence of ECLN in routine assessment of thyroid nodules is an easy and fast surveillance technique that increases the predictive value in diagnosing thyroid cancer, especially when the enlarged lymph nodes are on the same side as the thyroid nodule.

Prospective evaluation of solitary thyroid nodule on 18F-FDG PET/CT and high-resolution ultrasonography

PURPOSE

The utility of 18F-FDG PET/CT in the assessment of thyroid nodules is unclear as there are several conflicting reports on the usefulness of SUV as an indicator to distinguish benign from malignant thyroid lesions. This study incorporated an additional parameter, namely dual time point imaging, to determine the diagnostic accuracy of PET/CT imaging. The performance of 18F-FDG PET/CT was compared to that of high-resolution ultrasound which is routinely used for the evaluation of thyroid nodules.

METHODS

Two hundred patients with incidentally detected solitary thyroid nodules were included in the study. Each patient underwent ultrasound and PET/CT evaluation within 7 days of each other, reported by an experienced radiologist and nuclear medicine specialist, respectively, in a blinded manner. The PET/CT criteria employed were maximum SUV (SUV(max)) at 60 min and change in SUV(max) at delayed (120 min) imaging. Final diagnosis was based on pathological evaluation and follow-up.

RESULTS

Of the 200 patients, 26 had malignant and 174 had benign nodules. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of ultrasound were 80.8, 81.6, 39.6, 96.6 and 81.5%, respectively. Using SUV(max) at 60 min as the diagnostic criterion, the above indices were 80.8, 84.5, 43.8, 96.7 and 84%, respectively, for PET/CT. The SUV(max) of malignant thyroid lesions was significantly higher than benign lesions (16.2 +/- 10.6 vs. 4.5 +/- 3.1, respectively; p = 0.0001). Incorporation of percentage change in SUV(max) at delayed imaging as the diagnostic criterion yielded a slightly improved sensitivity, specificity, PPV, NPV and accuracy of 84.6, 85.6, 46.8, 97.4 and 85.5%, respectively. There was a significant difference in percentage change in SUV(max) between malignant and benign thyroid lesions (14.9 +/- 11.4 vs. -1.6 +/- 13.7, respectively; p = 0.0001). However, there was no statistically significant difference (95% confidence interval) between the diagnostic performance of PET/CT and ultrasound.

CONCLUSIONS

Routine use of 18F-FDG PET/CT with SUV(max) at 60 min as the sole diagnostic criterion does not appear to have a significant advantage over high-resolution ultrasound in the evaluation of thyroid nodules. Incorporation of dual time point imaging enhances image interpretation, and yields a higher diagnostic performance, yet it is not statistically significant. Bearing in mind the cost, limited availability and radiation exposure, routine use of 18F-FDG PET/CT for distinguishing benign from malignant thyroid nodules cannot be recommended.

Histopathologic findings related to the indeterminate or inadequate results of fine-needle aspiration biopsy and correlation with ultrasonographic findings in papillary thyroid carcinomas

OBJECTIVE

To determine histopathologic findings related to the indeterminate or inadequate result of fine-needle aspiration biopsy (FNAB) in papillary thyroid carcinomas (PTCs) and to correlate histopathological findings with ultrasonographic features of tumors.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of FNAB, histopathologic characteristics, and sonographic findings of the solid portion of 95 PTCs in 95 patients. All cases were pathologically confirmed by surgery. Histopathologic characteristics were analyzed for tumor distribution, microcystic changes, fibrosis, and tumor component. We assumed several histopathologic conditions to be the cause of indeterminate or inadequate results of FNAB, including: 1) an uneven tumor distribution, 2) > 30% microcystic changes, 3) > 30% fibrosis, and 4) < 30% tumor component. Ultrasonographic findings of each PTC were evaluated for echotexture (homogeneous or heterogeneous), echogenicity (markedly hypoechoic, hypoechoic, isoechoic, or hyperechoic), and volume of the nodule. We correlated histopathologic characteristics of the PTC with results of the FNAB and ultrasonographic findings.

RESULTS

From 95 FNABs, 71 cases (74%) were confirmed with malignancy or suspicious malignancy (PTCs), 21 (22%) had indeterminate results (atypical cells), and three (4%) were negative for malignancy. None of the assumed variables influenced the diagnostic accuracy of FNAB. Tumor distribution and fibrosis were statistically correlated with ultrasonographic findings of the PTCs (p < 0.05). Uneven tumor distribution was related with small tumor volume, and fibrosis over 30% was correlated with homogeneous echotexture, markedly hypoechoic and hypoechoic echogenicity, and small tumor volume (p < 0.05).

CONCLUSION

No histopathologic component was found to correlate with improper results of FNAB in PTCs. In contrast, two histopathologic characteristics, uneven distribution and fibrosis, were correlated with ultrasonographic findings.

A proposal for a thyroid imaging reporting and data system for ultrasound features of thyroid carcinoma

BACKGROUND

Several thyroid ultrasound (TUS) findings have been associated with an increased risk for thyroid cancer; however, there is no consensus as to the format and style for reporting the results of TUS. The objective of this study was to discover the features indicative of malignancy in thyroid nodules based on TUS, generate an equation using these features that would be predictive of malignancy in thyroid nodules, and stratify the results of this equation into TUS categories reflecting the probability of malignancy.

METHODS

We obtained odds ratios of TUS findings indicative of malignancy and probability of malignancy for each nodule as determined by logistic regression analysis of ultrasound (US) findings in 1694 patients who had US-guided fine-needle aspiration biopsy. We then generated an equation to predict the probability of malignancy based on TUS and developed categories ranging from lowest to highest probability of malignancy. We evaluated the reliability of this equation and the categories using cytology and histopathology information regarding malignancy in the thyroid nodules.

RESULTS

We characterized 12 aspects of thyroid nodules as seen on TUS and developed an equation to predict P(us), the probability of a nodule being malignant based on these US findings. The equation was P(us) = 1/(1 + e(-z)), where e is the mathematical constant 2.71828 and z is the logit of malignant thyroid nodule. P(us) was stratified into five categories based on the probability of a nodule being malignant as indicated by the findings (TUS 1, benign; TUS 2, probably benign; TUS 3, indeterminate; TUS 4, probably malignant; TUS 5, malignant). There was a significant correlation between the cytological category and the TUS 1 through TUS 5 categories (r = 0.491, p < 0.001).

CONCLUSIONS

We propose an equation to predict the probability of malignancy in thyroid nodules based on 12 features of thyroid nodules as noted on TUS. This equation, and the stratification of its results into categories, should be useful in reporting the findings of US for thyroid nodules and in guiding management decisions.

The role of BRAFV600E mutation and ultrasonography for the surgical management of a thyroid nodule suspicious for papillary thyroid carcinoma on cytology

BACKGROUND

This study was designed to investigate the role of BRAFV600E mutation status in cytology specimens and ultrasonography (US) when planning surgery for thyroid nodules with cytologic results suspicious for papillary thyroid carcinoma (PTC).

METHODS

From July 2008 to November 2008, 91 consecutive patients with cytologic results of suspicious for PTC underwent thyroidectomy. Before surgery, all patients received US-guided fine needle aspiration biopsy (US-FNAB) solely for the purpose of BRAFV600E mutation analysis of thyroid nodules suspicious for PTC on cytology. BRAFV600E mutations were tested by direct sequencing. We investigated the role of BRAFV600E mutation and US in planning the thyroid surgery.

RESULTS

Of 91 nodules suspicious for PTC, 42 (46.2%) were positive for the BRAFV600E mutation and confirmed to be PTC by histopathology. The positive predictive values of BRAFV600E mutation was 100%. Of the 49 nodules without the BRAFV600E mutation, 42 (85.7%) proved to be PTC. Thirty-nine of 42 (92.9%) PTCs were suspicious for malignant features on US. Two of seven (28.6%) benign lesions showed probably benign features. The sensitivity, positive predictive value, and accuracy of US in thyroid nodules without BRAFV600E mutations was 92.9% (39/42), 88.6% (39/44), and 83.7% (41/49), respectively.

CONCLUSIONS

The BRAFV600E mutation is a useful molecular marker for preoperative diagnosis of PTC and an indicator for therapeutic thyroid surgery in the nodule with cytologic results suspicious for PTC. In thyroid nodules without the BRAFV600E mutation, suspicious malignant features on US may help in planning the extent of thyroid surgery.

Usefulness of ultrasound-guided fine-needle aspiration cytology in the diagnosis of non-palpable small thyroid nodules: our growing experience

AIMS AND BACKGROUND

Contradictory approaches have been suggested for the management of non-palpable thyroid nodules. The aim of our study is to evaluate indications and limits of ultrasound-guided fine-needle aspiration cytology (US-FNAC) in the management of non-palpable infracentimetric thyroid nodules.

METHODS AND STUDY DESIGN

From September 2003 to June 2007 we studied 1043 patients with non-palpable thyroid nodules. We divided our series into three groups according to the diameter of the lesion in order to verify the effectiveness of US-FNAC for lesions <1 cm.

RESULTS

We assessed the cases with satisfactory and unsatisfactory results in the 3 groups into which the sample was divided. Our statistical analysis using the z-test showed there was no significant (p=0.05) difference in the percentage distribution of the unsatisfactory results in the 3 groups.

CONCLUSIONS

FNAC appears to be a useful diagnostic tool also for nodules <1 cm because the percentage of unsatisfactory results is not related to the size of the nodule.

US-guided fine-needle aspiration of thyroid nodules: indications, techniques, results

Fine-needle aspiration (FNA) biopsy of thyroid nodules is minimally invasive and safe and is usually performed on an outpatient basis. However, the optimal application of FNA requires not only technical skill but also an awareness of the limitations of the procedure, the indications for its use, the factors that affect the adequacy of the biopsy specimen, and the postprocedural management strategy. Ultrasonographic (US) features that are considered indications for FNA include single and multiple thyroid nodules. The results of FNA biopsy are operator dependent. In addition, the results may be affected by the lesion characteristics, the accuracy of lesion and needle localization, the method of guidance, the number of aspirated samples, the needle gauge, the aspiration technique, and the presence or absence of on-site facilities for immediate cytologic examination. With regard to postprocedural management, nodules that are diagnosed as benign on the basis of an adequate FNA specimen should be monitored with follow-up US. Circumstances that necessitate repeat FNA include sample inadequacy, nodule enlargement, cyst recurrence, or clinical or imaging findings that arouse suspicion about the presence of a malignancy even when cytologic findings in the biopsy specimen indicate benignity. Supplemental material available at radiographics.rsnajnls.org/cgi/content/full/28/7/1869/DC1.

Ultrasound-guided fine-needle aspiration biopsy of thyroid nodules: comparison in efficacy according to nodule size

BACKGROUND

The objective of this study was to compare the efficacy and procedure time of ultrasound-guided fine-needle aspiration biopsy (US-FNAB) of thyroid nodules, according to the nodule size.

METHODS

US-FNABs of thyroid nodules performed between June 2007 and December 2007 were studied. We divided these patients into three groups according to the largest diameter of their nodules. Group A consisted of patients with thyroid nodules less than or equal to 5 mm, group B of patients with thyroid nodules greater than 5 mm and less than or equal to 10 mm, and group C of patients with thyroid nodules greater than 10 mm. We retrospectively reviewed the cytopathology results and complications in all three patient groups and measured the separate, total US-FNAB procedure time for each of 20 randomly selected thyroid nodules.

RESULTS

US-FNAB was performed on 438 thyroid nodules in 253 patients. In groups A, B, and C, the adequacy rates from the first US-FNAB were 79.6% (90/113), 90.6% (125/138), and 95.2% (178/187), respectively. In groups A, B, and C, 113, 138, and 187 thyroid nodules in 100, 120, and 169 patients, respectively, revealed 59, 75, and 126 benign; 12, 11, and 9 suspicious for malignancy; 9, 32, and 29 malignant; 10, 7, and 14 inderminate for malignancy; and 23, 13, and 9 inadequate on the first US-FNAB. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were determined to be 85.7%, 100%, 100%, 94.9%, and 96.1% in group A; 97.7%, 100%, 100%, 98.7%, and 99.1% in group B; and 100%, 99.2%, 97.1%, 100%, and 99.4% in group C. The mean procedure times in groups A, B, and C were 2 minutes 33 seconds, 1 minute 50 seconds, and 1 minute 32 seconds, respectively. There were no significant patient complications in any of the three patient groups.

CONCLUSIONS

US-FNAB of thyroid nodules smaller than 5 mm in maximum diameter was less successful, and the sensitivity was lower than those of nodules larger than 5 mm. We considered, however, that the sampling adequacy and efficacy of US-FNAB of thyroid nodules less than 5 mm in maximum diameter was satisfactory in our series and should be similar in other centers with similar characteristics to ours.

Fine-needle aspiration biopsy versus ultrasound-guided fine-needle aspiration biopsy: cost-effectiveness as a frontline diagnostic modality for solitary thyroid nodules

BACKGROUND

Ultrasound-guided fine-needle aspiration biopsy (ultrasound-guided FNAB) is considered the diagnostic test of choice when a fine-needle aspiration biopsy (FNAB) returns an inconclusive diagnosis because of cytologic ambiguity or paucity of specimen.

METHODS

Cost-effectiveness analysis utilizing a decision tree was used to model the diagnostic strategies. The decision analysis model was parameterized using costs from a large, academic medical center and probabilities from existing literature. Outcomes included the incremental cost per additional case correctly diagnosed.

RESULTS

All data are reported as frontline ultrasound-guided FNAB strategy versus FNAB strategy-expected cost: $1329 versus $1312; expected number of cases correctly diagnosed (per 1000 biopsies): 980 versus 920; incremental cost per additional correctly diagnosed case: $289.

CONCLUSION

The use of ultrasound-guided FNAB as the initial modality for tissue biopsy of a thyroid nodule is more effective than traditional FNAB at an additional cost of $289 per additional correct diagnosis.

Increased expression of transketolase-like-1 in papillary thyroid carcinomas smaller than 1.5 cm in diameter is associated with lymph-node metastases

BACKGROUND

Patients with small papillary thyroid carcinoma (PTC) may have a high incidence of regional lymph-node (LN) metastases at presentation, and these are considered to be an independent risk factor for tumor recurrence. A mutated transketolase transcript (TKTL1) has been found up-regulated in different human malignancies, and strong TKTL1 protein expression has been associated with aggressiveness and poor patient survival in several epithelial cancers.

METHODS

TKTL1 protein expression was analyzed in 256 consecutive cases of PTCs <or=1.5 cm by immunohistochemistry with a specific anti-TKTL1 antibody. RNA analysis was performed by real-time polymerase chain reaction (PCR) in all cases for which frozen material was available, which resulted in 55 fragments of PTC.

RESULTS

Increased levels of TKTL1 transcript were detected in 50 of 55 analyzed tumors compared with their corresponding normal tissues. Significant differences in TKTL1 transcript levels were found between cases of PTC with and without LN metastases. In primary tumors, immunoreactivity for TKTL1 was detected in the majority of cases, ranging from 0% to 95.0% (mean, 50.11% +/- 27.75%). A significant association was found between TKTL1 protein expression and the presence of multifocality, bilaterality, extrathyroidal extension, vascular invasion, sclerosis, and LN metastases. In cases with LN metastases, a positive correlation was found between the TKTL1 protein expression in primary tumors and the number of metastatic LNs as well as the diameter of the largest metastatic area in LNs.

CONCLUSIONS

These findings suggest that TKTL1 overexpression in PTC <or=1.5 cm may be considered a factor that facilitates tumor growth and progression.

The role of ultrasound in thyroid nodules with a cytology reading of "suspicious for papillary thyroid carcinoma"

BACKGROUND

Irrespective of ultrasound (US) features, surgery is usually recommended for patients who have a fine-needle aspiration biopsy (FNAB) read as suspicious for papillary carcinoma (PTC). The aim of the present study was to evaluate the role of US in the management of thyroid nodules with a FNAB reading suspicious for PTC.

METHODS

Between August 2002 and May 2006, 303 patients who had thyroid nodules with a FNAB reading suspicious for PTC underwent surgery. The sonographic findings in the patients were classified as suspicious for malignancy or probably benign based on the US reading. The US readings and final pathological diagnoses of thyroid nodules were analyzed in these patients.

RESULTS

The malignancy rate was 84.2% in patients with a FNAB specimen suspicious for PTC. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the US were 96.4%, 74.5%, 92.7%, 94.9%, and 80.9%, respectively, in nodules read as suspicious for PTC on FNAB. Whereas 243 (96.4%) lesions were found to be malignant at surgery, in the 252 lesions that had ultrasound findings suspicious for malignancy, only 13 (25.5%) lesions were malignant out of the 51 that had US readings of probably benign (p < 0.05).

CONCLUSIONS

The probability of malignancy is much lower in thyroid nodules with benign US findings even if the FNAB is read as suspicious for PTC. Therefore, US may be useful in planning the extent of surgery in patients with a FNAB reading of suspicious for PTC. As thyroid malignancy occurs in approximately 26% of patients with cytology readings suspicious for PTC and benign-appearing US, the US reading alone is not sufficient to determine the need for surgery. The US and FNAB are complementary to each other and should be useful when providing informed consent before thyroid surgery.

High prevalence of carcinoma in ultrasonography-guided fine needle aspiration cytology of thyroid nodules

OBJECTIVE

The purpose of this study was to assess the rate of malignancy in thyroid nodules incidentally detected at sonography and to determine the diagnostic value of ultrasonography-guided fine needle aspiration cytology (USgFNAC) in thyroid nodules.

METHODS

Five hundred patients (84 men and 416 women) who had thyroid incidentalomas underwent USgFNAC at Konkuk University Hospital between August 2005 and July 2006. Thyroid sonography and guided aspiration was performed on all single nodules and on dominant nodules with suspected malignancy in cases of multinodular goiter.

RESULTS

Five hundred fifty-eight nodules from 500 patients were aspirated using ultrasonography guidance. The USgFNAC results for all patients were as follows: 307 (61.4%) benign, 108 (21.6%) suggestive of malignancy, 56 (11.2%) indeterminate, and 29 (5.8%) inadequate for cytologic diagnosis. The rate of malignancy was significantly higher in women than in men (23.6% in women vs 11.9% in men, p<0.01). Ultrasonographic characteristics that had a significant association with thyroid malignancy included solid echocomponent, hypoechogenecity, ill defined margin, and presence of microcalcifications (p<0.05). Eighty-eight patients underwent surgical resection. The positive predictive value of USgFNAC was 90.2% (74/82), and the accuracy index was 84.1% (74/88). In 80 patients with well-differentiated thyroid carcinoma after surgery, 49% (39/80) had lesions smaller than 1 cm.

CONCLUSION

The rate of malignancy in incidental thyroid nodules on USgFNAC was 21.6%. Ultrasonographic features could be useful in differentiating between benign and malignant nodules.

The radiologist and the cytologist in diagnosing thyroid nodules: results of cooperation

PURPOSE

This study was done to evaluate the effectiveness of cooperation between the radiologist and the cytopathologist in ultrasound-guided fine-needle aspiration biopsy (FNAB) of thyroid nodules.

MATERIALS AND METHODS

Since 1995, FNAB of thyroid nodules at our department has been performed under ultrasound guidance by the radiologist with a cytopathologist present on-site. The results of ultrasound-guided FNAB procedures performed at our department in 1995, 1999, and 2005 were retrospectively evaluated and compared with those of other departments in the Trieste Province where thyroid nodules are sampled by palpation-guided FNAB performed by a clinician.

RESULTS

From 1995 to 2005, the number of ultrasound-guided FNAB procedures performed at our department rose steadily, whereas the number of inadequate samples fell progressively. In patients who underwent surgery, the number of discrepancies between the cytological findings and the final histological diagnoses decreased progressively.

CONCLUSIONS

Ultrasound-guided FNAB performed by the radiologist with a cytopathologist present on-site is superior to palpation-guided FNAB. The results are optimised by cooperation between the radiologist and cytologist.

Sonographically guided fine-needle biopsy of thyroid nodules: the effects of nodule characteristics, sampling technique, and needle size on the adequacy of cytological material

AIM

To evaluate the effects of sonographic characteristics of thyroid nodules, the diameter of needle used for sampling, and sampling technique on obtaining sufficient cytological material (SCM).

MATERIALS AND METHODS

We performed sonography-guided fine-needle biopsy (FNB) in 232 solid thyroid nodules. Size-, echogenicity, vascularity, and localization of all nodules were evaluated by Doppler sonography before the biopsy. Needles of size 20, 22, and 24 G were used for biopsy. The biopsy specimen was acquired using two different methods after localisation. In first method, the needle tip was advanced into the nodule in various positions using a to-and-fro motion whilst in the nodule, along with concurrent aspiration. In the second method, the needle was advanced vigorously using a to-and-fro motion within the nodule whilst being rotated on its axis (capillary-action technique).

RESULTS

The mean nodule size was 2.1+/-1.3 cm (range 0.4-7.2 cm). SCM was acquired from 154 (66.4%) nodules by sonography-guided FNB. In 78 (33.6%) nodules, SCM could not be collected. There was no significant difference between nodules with different echogenicity and vascularity for SCM. Regarding the needle size, the lowest rate of SCM was obtained using 20 G needles (56.6%) and the highest rate of adequate material was obtained using 24 G needles (82.5%; p=0.001). The SCM rate was 76.9% with the capillary-action technique versus 49.4% with the aspiration technique (p<0.001).

CONCLUSION

Selecting finer needles (24-25 G) for sonography-guided FNB of thyroid nodules and using the capillary-action technique decreased the rate of inadequate material in cytological examination.

Treatment for microcarcinoma of the thyroid--clinical experience

AIMS AND BACKGROUND

Papillary microcarcinoma of the thyroid is a specific subgroup of papillary thyroid carcinoma (PTC) and account for up to 30% of all PTC. According to the World Health Organization, papillary microcarcinoma of the thyroid (PMC) is defined as a papillary thyroid carcinoma measuring <or=10 mm in the greatest dimension. The relative rate of PMC is increasing in patients with differentiated thyroid carcinoma (DTC) mainly due to more frequent use and improvement of ultrasonography and fine-needle aspiration biopsy, and also more accurate histopathological examination of surgical specimens. The high incidence of PMC found in autopsy studies (up to 35%) suggests that most of them have a benign behavior. The locoregional recurrence has been reported in up to 20% of PMC patients and several cases of distant metastases have also been described. The 'ideal' therapeutic approach in PMC patients remains a subject of debate among endocrinologists and surgeons. Treatment of PMC in different departments varies from partial thyroidectomy to total thyroidectomy and radioiodine treatment. The main question in this group of patients is "How should PMC patients be treated?" The aim of this study was to investigate retrospectively the frequency and clinical behavior of PMC of the thyroid gland in our department and also to identify the optimal treatment of this group of patients.

MATERIALS AND METHODS

For this retrospective study, we evaluated 120 patients with PMC in our department (between 1997 and 2005). The mean age of patients at diagnosis was 43 +/- 13 years (range 17-67 years). The female to male ratio was 87.5% (105 females, 15 males). The mean follow-up period of patients in this study was 45 months (16-84 months). Surgical treatment of patients with PMC in our department consisted of a bilateral total thyroidectomy in 25 patients (21%), and a bilateral near total thyroidectomy in 95 patients (79%). In the evaluation of our patients, multifocal PMC had a relative frequency of 15% (18/120 patients). The patients were informed about the different therapeutic strategies and the possible necessity for more frequent radioiodine treatment to eliminate thyroid remnants. All of the patients in our retrospective study had radioiodine (RAI) ablation therapy for residual thyroid tissue.

RESULTS

All patients received an RAI treatment dose which ranged from 75-150 mCi (2.7-5.5 GBq). Our criteria for ablation are as follows: negative I-131 WBS and very low serum Tg levels (<1 ng/mL). In 112/120 patients (93.3%), the thyroid remnant was ablated with a single dose of I-131 75-150 mCi (2.7-5.5 GBq). A second radioiodine treatment was necessary in 8 patients (7%), because of locoregional recurrence (required mean cumulative doses of 8.2-11 GBq I-131). Locoregional reccurence occurred in 2 patients with unifocal tumor, without capsular invasion or lymph node metastases and in 6 patients with multifocal tumor and/or in patients with capsular invasion or lymph node metastases. After a second radioiodine treatment, all of these 8 patients were ablated. All 120 patients remained free from disease (negative I-131 whole body scan, unmeasurable thyroglobulin levels) after a median follow-up period of 45 months and there was no recorded disease-related mortality.

CONCLUSION

The treatment of patients with PMC should be no different from the treatment of patients with PTC, and thyroidectomy followed by radioiodine therapy may be a possible option for treatment of papillary microcarcinoma.

Over-expression of c-kit in a primary leiomyosarcoma of the thyroid gland

Primary leiomyosarcoma of the thyroid gland is rare. In this paper, we report a case of high-grade leiomyosarcoma of the thyroid gland in a 43-year-old man. Lung metastasis was also noted in this patient. Despite of aggressive surgical treatment, the patient died of uncontrolled local recurrent disease 6 months after the initial operation. Immunohistochemical studies showed the tumor cells were positive for c-kit proto-oncogene product. Imatinib mesylate was used as a post-operative adjuvant treatment but the response was poor. The role of tyrosine kinase inhibitors on the treatment of thyroid leiomyosarcomas is still unclear because this is the first report of c-kit over-expression in such tumors. Nevertheless, our results show that c-kit over-expression might not be an indicator of good response to imatinib mesylate treatment in thyroid leiomyosarcomas.

Comparison of palpation-guided fine-needle aspiration biopsy to ultrasound-guided fine-needle aspiration biopsy in the evaluation of thyroid nodules

OBJECTIVE

Although fine-needle aspiration biopsy (FNAB) of thyroid nodules is a reliable and simple method, the diagnostic value may be limited by inadequate and false-negative results. In this prospective study, we compared palpation-guided FNAB (PGFNAB) with ultrasound-guided FNAB (UGFNAB) to establish the rates of inadequate material and cost-effectiveness.

DESIGN

A total of 285 thyroid nodules in 215 patients were included in the study. Palpable nodules with the greatest diameter between 1 and 2.5 cm were included in the study. PGFNAB and UGFNAB techniques were applied to the same nodule by the same operator. Cytologic evaluations were performed by the same cytologist in a blinded fashion. To provide cost analysis, the prices obtained from different hospitals were evaluated.

MAIN OUTCOME

The rates of inadequate material for PGFNAB and UGFNAB were significantly different as 32.3% and 21.4%, respectively (p = 0.004). There was significantly higher inadequate material rate in PGFNAB group for small-sized nodules (greatest nodule diameter between 10 and 15 mm) (p = 0.009), despite inadequate material rate was not significant for both procedures for larger sized nodules. False-negative results were 15.8% for PGFNAB and 5.6% for UGFNAB. Regarding cost analysis, the difference between the two methods was 20 dollars on average for each patient.

CONCLUSIONS

We consider UGFNAB to be superior to PGFNAB for obtaining adequate material especially for small-sized nodules, as well as providing more accurate cytologic evaluation. Indeed, the difference between the costs of two procedures might be acceptable.

Ultrasound guidance improves the adequacy of our preoperative thyroid cytology but not its accuracy

AIMS

Our thyroid cytology audit results of 1990-1995 showed an unsatisfactory rate of 43.1% and prediction of neoplasia with a sensitivity of 86.8%. Increasingly, ultrasound scan (USS)-guided core sampling for cytology is proving a valuable tool instead of freehand fine needle aspiration (FNA) or following unsatisfactory freehand FNA. We present the results of freehand FNA and USS-guided core samples for cytology in two separate patient groups in our centre.

METHODS

Patients who had a thyroid resection and preoperative thyroid cytology in our institution between 1996 and 2002 were included. The histological diagnoses were correlated with the preceding cytology results.

RESULTS

A total of 450 FNAs were performed on 394 patients. Freehand FNAs were performed for 348 (77.3%) samples and USS-guided core for 102 (22.7%) samples; 121 (26.8%) were repeat aspirates performed on 45 patients. Using aspiration cytology (AC) grading, freehand FNA was cytologically inadequate (AC0 or AC1) in 34.8% cases whereas USS-guided core was inadequate in 17.6% cases (P = 0.001). Freehand FNA (AC3, AC4, AC5) predicted neoplasia with a sensitivity of 83.2%, specificity of 46.6%, accuracy of 63.0%, positive predictive value of 56.0% and negative predictive value of 77.1%. USS-guided core sample for cytology (AC3, AC4, AC5) predicted neoplasia with a sensitivity of 93.5%, specificity of 26.0%, accuracy of 51.9%, positive predictive value of 43.9% and negative predictive value of 86.7%.

CONCLUSIONS

Although USS-guided core provides more satisfactory specimens than freehand FNA, in our centre it does not provide increased accuracy.

Diagnostic Accuracy of Palpation-Guided and Image-Guided Fine-Needle Aspiration Biopsy of the Thyroid

We conducted a retrospective study to compare the sensitivity and specificity of traditional palpation-guided fine-needle aspiration biopsy (FNAB) performed by clinicians and pathologists with that of image-guided FNAB performed by radiologists for the evaluation of thyroid nodules. We reviewed the medical records of 89 patients who had undergone thyroid FNAB and subsequent surgical excision and pathology. Of this group, 58 patients had undergone palpation-guided FNAB performed by a clinician, 20 had undergone palpation-guided FNAB performed by a pathologist, and 11 had undergone image-guided FNAB performed by a radiologist. The sensitivity of the three techniques was 86, 100, and 100%, respectively, and the specificity was 78, 94, and 44%; there were no statistically significant differences in sensitivity or specificity among the three groups. Our data indicate that FNAB of the thyroid can be performed with equal reliability by clinicians, pathologists, and radiologists.

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.