Thyroid nodule update on diagnosis and management

The Keap1/Nrf2 Signaling Pathway in the Thyroid-2020 Update

The thyroid gland has a special relationship with oxidative stress. On the one hand, like all other tissues, it must defend itself against reactive oxygen species (ROS). On the other hand, unlike most other tissues, it must also produce reactive oxygen species in order to synthesize its hormones that contribute to the homeostasis of other tissues. The thyroid must therefore also rely on antioxidant defense systems to maintain its own homeostasis in the face of continuous self-exposure to ROS. One of the main endogenous antioxidant systems is the pathway centered on the transcription factor Nuclear factor erythroid 2-related factor 2 (Nrf2) and its cytoplasmic inhibitor Kelch-like ECH-associated protein 1 (Keap1). Over the last few years, multiple links have emerged between the Keap1/Nrf2 pathway and thyroid physiology, as well as various thyroid pathologies, including autoimmunity, goiter, hypothyroidism, hyperthyroidism, and cancer. In the present mini-review, we summarize recent studies shedding new light into the roles of Keap1/Nrf2 signaling in the thyroid.

Contrast-enhanced ultrasound for the differential diagnosis of thyroid nodules: An updated meta-analysis with comprehensive heterogeneity analysis

The diagnostic accuracy of contrast-enhanced ultrasound (CEUS) for distinguishing malignant thyroid nodules from benign thyroid nodules remains controversial. This meta-analysis was performed to evaluate the overall diagnostic value of CEUS for the characterization of thyroid nodules. Relevant studies were identified by searching PubMed, Embase and the Cochrane Library until August 1th 2019 to assess the overall diagnostic accuracy of CEUS. 37 eligible studies were included in the present meta-analysis. The pooled sensitivity, specificity, positive likelihood rate, negative likelihood rate and diagnostic odds ratio of CEUS were 0.87, 0.83, 5.38, 0.17 and 38.94, respectively, with the AUC of 0.9263. Subgroup analysis showed the heterogeneity was greatly reduced in small nodules group (≤ 1 cm) (I2 = 0.0%), while heterogeneity was still observed in the group of variable sizes group (I2 = 69.5%). However, meta-regression analysis revealed that only diagnostic criterion was the major source of heterogeneity (p = 0.0259). The risk of publication bias was negligible (p = 0.35). CEUS exhibited high accuracy for the identification of thyroid nodules and might provide additional perfusion information for the current US imaging reporting systems.

Diagnostic accuracy of preoperative palpation- versus ultrasound-guided thyroid fine needle aspiration cytology: an observational study

BACKGROUND

Thyroid fine needle aspiration (FNA) is the mainstay for diagnosis of malignancy, and is an integral part of current thyroid nodule assessment. The present study analyzes the diagnostic accuracy of palpation-directed versus ultrasound guided fine-needle aspiration in patients who underwent surgery for thyroid nodules.

METHODS

A retrospective chart review of all consecutive patients who had FNA biopsy (palpation or ultrasound guided) of thyroid nodules and underwent thyroid gland surgery between 1998 and 2014 was conducted. The FNA findings of the palpation-guided and ultrasound-guided groups were compared for baseline characteristics. Moreover, the diagnostic accuracy of FNA findings and surgical histopathology results were analyzed.

RESULTS

A total of 1174 patients were included in the study with a mean age of 46.3 ± 11.7 years and the majority were females (75.5%). Among the study population, 392 (33.4%) patients underwent US-guided FNA; 570 (48.6%) had palpation-guided FNA in clinic and no FNA was done in 212 (18%) cases. Patients underwent US-guided FNA were more likely to have suspicion of malignancy (p = 0.001), and had indeterminate findings (p = 0.001). On the other hand, palpation-guided FNA group had significantly higher frequency of benign cytology (p = 0.001). With respect to the suspicion for malignancy as well as malignancy, the US-guided group had a similar diagnostic accuracy in comparison to the palpation group. The proportion of malignancy finding on US-guided FNA (8.9%) was higher than the palpation-guided FNA (6.4%) that had been confirmed on postoperative histopathological examination (p = 0.95).

CONCLUSION

The present study demonstrates higher sensitivity of US-guided thyroid FNA biopsies over palpation-guided FNA for the suspicion of malignancy; however, the accuracy is comparable. Moreover, both groups showed more postoperative malignancy in the benign and unsatisfactory categories than predicted in the Bethesda system. Further prospective studies are needed to underpin a realistic correlation between FNA and final histopathology reports.

Data-Driven Analysis of Radiologists' Behavior for Diagnosing Thyroid Nodules

Thyroid nodule has been a common and serious threaten to human health. With the identification and diagnosis of thyroid nodules in the general population, large volumes of examination reports in clinical practice have been accumulated. They provide data basics of analyzing radiologists' behavior of diagnosing thyroid nodules. To conduct data-driven analysis of radiologists' behavior, an experimental framework is designed based on belief rule base, which is essentially a white box for knowledge representation and uncertain reasoning. Under the framework, with 2744 examination reports of thyroid nodules in the period from January 2012 to February 2019 that have been collected from a tertiary hospital located in Hefei, Anhui, China, experimental results are obtained from conducting missing validation, self-validation, and mutual validation. Three principles are then concluded from the results and corresponding analysis. The first is that missing features on some criteria are considered as benign ones by default, the second is that there is generally inconsistency between the recorded features on criteria and the overall diagnosis, and the third is that different radiologists have different diagnostic preferences. These three principles reflect three diagnostic behavioral characteristics of radiologists, namely reliability, inconsistency, and independence. Based on the three principles and radiologists' behavioral characteristics, managerial insights in a general case are concluded to make the findings in this study available in other situations.

Application of a machine learning algorithm to predict malignancy in thyroid cytopathology

BACKGROUND

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) comprises 6 categories used for the diagnosis of thyroid fine-needle aspiration biopsy (FNAB). Each category has an associated risk of malignancy, which is important in the management of a thyroid nodule. More accurate predictions of malignancy may help to reduce unnecessary surgery. A machine learning algorithm (MLA) was developed to evaluate thyroid FNAB via whole slide images (WSIs) to predict malignancy.

METHODS

Files were searched for all thyroidectomy specimens with preceding FNAB over 8 years. All cytologic and surgical pathology diagnoses were recorded and correlated for each nodule. One representative slide from each case was scanned to create a WSI. An MLA was designed to identify follicular cells and predict the malignancy of the final pathology. The test set comprised cases blindly reviewed by a cytopathologist who assigned a TBSRTC category. The area under the receiver operating characteristic curve was used to assess the MLA performance.

RESULTS

Nine hundred eight FNABs met the criteria. The MLA predicted malignancy with a sensitivity and specificity of 92.0% and 90.5%, respectively. The areas under the curve for the prediction of malignancy by the cytopathologist and the MLA were 0.931 and 0.932, respectively.

CONCLUSIONS

The performance of the MLA in predicting thyroid malignancy from FNAB WSIs is comparable to the performance of an expert cytopathologist. When the MLA and electronic medical record diagnoses are combined, the performance is superior to the performance of either alone. An MLA may be used as an adjunct to FNAB to assist in refining the indeterminate categories.

Causes of misdiagnoses by thyroid fine-needle aspiration cytology (FNAC): our experience and a systematic review

Objective

FNA is a simple, safe, cost-effective and accurate diagnostic tool for the initial screening of patients with thyroid nodules. The aims of this study were to determine the diagnostic utility of FNAC performed in our institution, assess the cytomorphologic features that contribute to diagnostic errors and propose improvement measures.

Methods

A total of 2781 FNACs were included in the study, and 1122 cases were compared with their histological diagnoses. We retrospectively reexamined our discordant (both false-negative and false-positive) cases and performed a systematic review of previous studies on causes of misdiagnoses.

Results

When DC V and DC VI were both considered cytologic-positive, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were 98.3, 30.9, 94.9, 58.3 and 93.5%, respectively. If DC VI was considered cytologic-positive, the sensitivity, specificity, PPV, NPV and diagnostic accuracy of FNAC were 98.0, 84.0, 99.4, 58.3, and 97.5% respectively. The main cause of false-negative diagnoses was sampling error (13/15, 86.7%), while interpretation error led to the majority of the false-positive diagnoses (38/47, 80.9%). Overlapping cytological features in adenomatous hyperplasia, thyroiditis and cystic lesions were the major factors contributing to interpretation errors, while the size and number of nodules may have led to false-negative diagnoses because of heterogeneity and unsampled areas.

Conclusions

The sensitivity and PPV of thyroid FNAC in our institution were higher than those in the published data, while the specificity and NPV were lower. Regarding the FNA category DC V, a frozen section analysis during diagnostic lobectomy is necessary. Multiple passes should be performed in various parts of a large nodule or from different nodules to reduce the risk of false-negative findings. Cytopathologists should strengthen their criteria for the identification of adenomatous hyperplasia, thyroiditis and cystic lesions to avoid false-positive diagnoses. NIFTP has little effect on diagnostic accuracy and the distribution of diagnostic errors.

Value of CT Features in the Diagnosis of Papillary Thyroid Tumors in Incidental Thyroid Nodules

The present work has investigated the value of computed tomography (CT) features in the diagnosis of papillary thyroid tumors in the incidental thyroid nodules (ITNs). In the 82 enrolled patients, 101 thyroid nodules were incidentally found by the neck CT scanning, among which 49 were histologically confirmed to be papillary thyroid carcinoma (PTC) while the other 52 were nodular goiter (NG). The tumor location, size, shape, tiny calcification, cystic change, and signs of an irregular ring, marginal defects, and enhanced blurring were all depicted by CT features. Both univariate and multivariate analyses were employed to identify independent predictors of PTC. The univariate analysis of PTC and NG showed that four CT features were statistically significant, including tiny calcification and signs of an irregular ring, marginal defects, and enhanced blurring. Furthermore, the multivariate logistic regression model indicated that signs of an irregular ring, marginal defects, and enhanced blurring were strongly correlated with PTC, of which the odds ratio (OR) was 27.374 (95% CI: 5.871∼127.636), 28.587 (95% CI: 4.139∼197.460), and 4.315 (95% CI: 0.858∼21.694), respectively. In the predictive model of PTC, the value of sensitivity, specificity, accuracy, and Youden index was 87.8%, 94.2%, 91.1%, and 0.82 with a likelihood ratio of 15.1. Therefore, the signs of an irregular ring, marginal defects, and enhanced blurring may be helpful in the diagnosis of PTC in incidentally found thyroid nodules.

High-Score US-Suspicious Subcentimeter Thyroid Nodules: What Factors Affect Adequate Sampling of US-Guided Fine-Needle Aspiration Biopsy?

BACKGROUND

Fine-needle aspiration biopsy (FNAB) is diagnostic standard for thyroid nodules. However, the influence of adequate sample rate of US-guided FNAB for subcentimeter thyroid nodules is not known well.

OBJECTIVES

To assess the factors affecting adequate sample rate of US-guided FNAB for subcentimeter thyroid nodules.

METHODS

Three hundred and forty-nine consecutive US-guided FNAB procedures were performed in 344 patients with subcentimeter thyroid nodules. The adequate sample rate was analyzed for all nodules on the basis of nodule-related and technical factors. The factors affecting adequate sample rate of US-guided FNAB for subcentimeter thyroid nodules were determined by multivariate logistic regression.

RESULTS

The adequate sample rate increased with larger nodules (72.7% for 3-6 mm nodules and 84.9% for 7-10 mm nodules (P=0.007)). The adequate sample rate was 63.9%, 81.3%, and 90.6% in nodules with macrocalcifcation, microcalcification, and no calcification, respectively (P < 0.001). The adequate sample rate was 71.8% for biopsies performed with a perpendicular needle path and 85.0% with a parallel needle path (P=0.004). The significant factors affecting adequate sample rate of US-guided FNAB for subcentimeter thyroid nodules were nodule size (P < 0.001; odds ratio (OR) for 7-10 mm nodules was approximately 3.0 times higher than that for 3-6 mm nodules), calcification (P < 0.001; OR for nodules without calcification was approximately 5.3 times higher than that for the nodules with macrocalcification), and needle path (P=0.044; OR for the use of the parallel needle path was about 1.8 times higher than that for the perpendicular needle path).

CONCLUSION

Nodule size, calcification, and needle path were the determinants of sample adequacy. The adequate sample rate was higher in larger nodules, in nodules without calcification, and upon using a parallel needle path for biopsy.

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC): A report of 2,781 cases in a Chinese population

Objective

To evaluate the diagnostic utility of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) at Peking University Cancer Hospital, the incidence of noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), and the impact of reclassification on cytopathological outcomes.

Methods

We performed a retrospective study of thyroid fine-needle aspiration (FNA) cases between April 2014 and March 2019. The FNA results were classified according to TBSRTC. Post-surgery histological findings were followed up.

Results

A total of 2,781 thyroid FNAs were performed. The incidences of the 6 diagnostic categories (DCs I-VI) were 14.8%, 17.1%, 15.8%, 2.3%, 11.6% and 38.5%, respectively. A total of 1,122 patients (40.3%) had corresponding histological results. NIFTP accounted for 0.4% of papillary thyroid carcinoma (PTC) cases, and there was no significant difference in the risk of malignancy (ROM) for each TBSRTC DC between "NIFTP=carcinoma (Ca)" and "NIFTP≠Ca". When "NIFTP=Ca", the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of TBSRTC were 98.0%, 84.0%, 99.4%, 58.3%, and 97.5%, respectively. When "NIFTP≠Ca", the sensitivity, specificity, PPV, NPV and accuracy of the TBSRTC were 98.1%, 81.5%, 99.3%, 61.1%, and 97.5%, respectively.

Conclusions

TBSRTC is effective in the preoperative diagnosis of thyroid nodules in Peking University Cancer Hospital. The impact of the reclassification of NIFTP on cytopathological outcomes is limited because of its low incidence, and the revised ROMs are not suitable for Asian patients.

Anterior Cervical Discectomy and Fusion combined with thyroid gland surgery, a tailored case and literature review

Background

Nowadays, Anterior Cervical Discectomy and Fusion (ACDF) is considered a routine procedure. However, unexpected difficulties do occasionally arise, especially when anterior neck pathologies or anatomical variations are encountered. In such cases, proactive thinking will allow surgeons to tailor appropriately their approach and eliminate surgical risks.

Case presentation

We present the case of a 50-year-old male patient suffering from left upper limb radiculopathy that underwent a C7-T1 ACDF combined with a hemithyroidectomy. Excision of the right thyroid lobe was offered to the patient because of a goiter found during the preoperative work-up. Furthermore, the hemithyroidectomy provided a wide surgical field so the ACDF performed without excreting excessive traction to the adjacent neck structures.

Conclusions

The patient had an uncomplicated post-operative. To our knowledge this is the first report of a planned hemithyroidectomy being carried out as the first step towards an ACDF procedure.

Impact of ultrasound angiography combined with fine needle aspiration for the diagnosis of thyroid nodules

BACKGROUND

This study aims to systematically investigate the impact of ultrasound angiography (UA) combined with fine needle aspiration (FNA) for the diagnosis of thyroid nodules (TNs).

METHODS

The following electronic databases will be searched: MEDLINE, EMBASE, Cochrane Library, PsycINFO, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. We will search them from their inceptions to the present without language limitations. We will consider all case-controlled studies on investigating the impact of diagnosis UA combined FNA for TNs. We will apply Quality Assessment of Diagnostic Accuracy Studies tool to assess methodological quality for all eligible studies.

RESULTS

In this study, outcomes consist of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio. All these outcomes will be analyzed to evaluate the diagnostic accuracy of UA combined with FNA for TNs.

CONCLUSION

This study will provide evidence of the diagnostic accuracy of UA combined with FNA for TNs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019138884.

Thyroid nodules: diagnosis and management

Thyroid nodules are common. Their importance lies in the need to assess thyroid function, degree of and future risk of mass effect, and exclude thyroid cancer, which occurs in 7-15% of thyroid nodules. There are four key components to thyroid nodule assessment: clinical history and examination, serum thyroid stimulating hormone (TSH) measurement, ultrasound and, if indicated, fine-needle aspiration (FNA). If the serum TSH is suppressed, a thyroid scan with ⁹⁹Tc can distinguish between a solitary hot nodule, a toxic multinodular goitre or, less commonly, thyroiditis or Graves' disease within a coexisting nodular thyroid. Scintigraphically cold nodules are evaluated in the same way as in the setting of normal or elevated serum TSH levels. Thyroid ultrasonography should be performed only for palpable goitre and thyroid nodules and by specialists with expertise in thyroid sonography. Routine thyroid cancer screening is not recommended, except in high risk individuals, as the detection of early thyroid cancer has not been shown to improve survival. FNA may be performed for nodules ≥ 1.0 cm depending on clinical and sonographic risk factors for thyroid cancer. FNA specimens should be read by an experienced cytopathologist and be reported according to the Bethesda Classification System. Molecular analysis of indeterminate FNA samples has potential to better discriminate benign from malignant nodules and thus guide management. Surgery is indicated for FNA findings of malignancy or indeterminate cytology when there is a high risk clinical context. Surgery may also be indicated for suspicion of malignancy; larger nodules, especially with symptoms of mass effect; and in some patients with thyrotoxicosis.

What is the Appropriate Nodular Diameter in Thyroid Cancer for Extraction by Transoral Endoscopic Thyroidectomy Vestibular Approach Without Breaking the Specimens? A Surgicopathologic Study

Transoral Endoscopic Thyroidectomy Vestibular Approach (TOETVA) is a novel technique with better cosmetic results. However, extraction of a large malignant thyroid nodule from the central incision of TOETVA necessitates breaking it into pieces to avoid mental nerve injury, a situation that may violate a proper oncological surgery. In this study, we sought the appropriate nodular diameter in thyroid cancer to be removed in an intact status through the central incision of the TOETVA technique. A total of 27 cases of thyroid nodules were operated using the TOETVA technique from Aug 2016 to July 2017. Excluding 10 benign goiters, the specimens of 17 thyroid cancer cases were divided into intact (group T, n=7) and fragmented (group F, n=10), with a median nodular diameter of 18.35 and 30.30 mm, respectively. Receiver operating characteristic (ROC) curve analysis revealed that the safest nodular diameter is 20 mm, with 100% sensitivity and 87.5% specificity.

Ultrasound-guided fine needle aspiration of thyroid nodules with on-site cytological examination: Diagnostic efficacy, prevalence, and factors predicting for Bethesda category I results

BACKGROUND AND OBJECTIVE

Ultrasound-guided fine needle aspiration of thyroid nodules with on-site cytological examination may decrease the number of Bethesda categoryI cytologies. The study objective was to evaluate our second-year experience with this procedure to analyze diagnostic efficacy, prevalence, and factors predicting for Bethesda categoryI results.

PATIENTS AND METHOD

A retrospective study was conducted of 279 nodules from 233 patients. Ultrasound -guided fine needle aspiration was performed according to the 2015 criteria of the American Thyroid Association. A specimen of each aspiration was air-fixed on site before Diff-Quik staining and microscopic examination to assess its suitability; otherwise, nodule aspiration was repeated up to 5times. Diagnostic efficacy was assessed based on sensitivity and specificity on the cytological categories BethesdaII and BethesdaVI.

RESULTS

Diagnostic sensitivity and specificity were both 100%, 5.4% Bethesda categoryI results were obtained, and variables independently associated were age (4.7% increase per year of life) and nodule volume (2.3% increase per each 1mL of volume).

CONCLUSIONS

Ultrasound-guided fine needle aspiration of thyroid nodules with on-site cytological examination allows for a high diagnostic efficacy and has been shown to be a highly relevant procedure because it has a very low rate of cytological results of Bethesda categoryI, whose risk has been higher in older subjects and with larger nodules.

Diagnosis of thyroid cancer using deep convolutional neural network models applied to sonographic images: a retrospective, multicohort, diagnostic study

BACKGROUND

The incidence of thyroid cancer is rising steadily because of overdiagnosis and overtreatment conferred by widespread use of sensitive imaging techniques for screening. This overall incidence growth is especially driven by increased diagnosis of indolent and well-differentiated papillary subtype and early-stage thyroid cancer, whereas the incidence of advanced-stage thyroid cancer has increased marginally. Thyroid ultrasound is frequently used to diagnose thyroid cancer. The aim of this study was to use deep convolutional neural network (DCNN) models to improve the diagnostic accuracy of thyroid cancer by analysing sonographic imaging data from clinical ultrasounds.

METHODS

We did a retrospective, multicohort, diagnostic study using ultrasound images sets from three hospitals in China. We developed and trained the DCNN model on the training set, 131 731 ultrasound images from 17 627 patients with thyroid cancer and 180 668 images from 25 325 controls from the thyroid imaging database at Tianjin Cancer Hospital. Clinical diagnosis of the training set was made by 16 radiologists from Tianjin Cancer Hospital. Images from anatomical sites that were judged as not having cancer were excluded from the training set and only individuals with suspected thyroid cancer underwent pathological examination to confirm diagnosis. The model's diagnostic performance was validated in an internal validation set from Tianjin Cancer Hospital (8606 images from 1118 patients) and two external datasets in China (the Integrated Traditional Chinese and Western Medicine Hospital, Jilin, 741 images from 154 patients; and the Weihai Municipal Hospital, Shandong, 11 039 images from 1420 patients). All individuals with suspected thyroid cancer after clinical examination in the validation sets had pathological examination. We also compared the specificity and sensitivity of the DCNN model with the performance of six skilled thyroid ultrasound radiologists on the three validation sets.

FINDINGS

Between Jan 1, 2012, and March 28, 2018, ultrasound images for the four study cohorts were obtained. The model achieved high performance in identifying thyroid cancer patients in the validation sets tested, with area under the curve values of 0·947 (95% CI 0·935-0·959) for the Tianjin internal validation set, 0·912 (95% CI 0·865-0·958) for the Jilin external validation set, and 0·908 (95% CI 0·891-0·925) for the Weihai external validation set. The DCNN model also showed improved performance in identifying thyroid cancer patients versus skilled radiologists. For the Tianjin internal validation set, sensitivity was 93·4% (95% CI 89·6-96·1) versus 96·9% (93·9-98·6; p=0·003) and specificity was 86·1% (81·1-90·2) versus 59·4% (53·0-65·6; p<0·0001). For the Jilin external validation set, sensitivity was 84·3% (95% CI 73·6-91·9) versus 92·9% (84·1-97·6; p=0·048) and specificity was 86·9% (95% CI 77·8-93·3) versus 57·1% (45·9-67·9; p<0·0001). For the Weihai external validation set, sensitivity was 84·7% (95% CI 77·0-90·7) versus 89·0% (81·9-94·0; p=0·25) and specificity was 87·8% (95% CI 81·6-92·5) versus 68·6% (60·7-75·8; p<0·0001).

INTERPRETATION

The DCNN model showed similar sensitivity and improved specificity in identifying patients with thyroid cancer compared with a group of skilled radiologists. The improved technical performance of the DCNN model warrants further investigation as part of randomised clinical trials.

FUNDING

The Program for Changjiang Scholars and Innovative Research Team in University in China, and National Natural Science Foundation of China.

American Head and Neck Society Endocrine Section clinical consensus statement: North American quality statements and evidence-based multidisciplinary workflow algorithms for the evaluation and management of thyroid nodules

BACKGROUND

Care for patients with thyroid nodules is complex and multidisciplinary, and research demonstrates variation in care. The objective was to develop clinical guidelines and quality metrics to reduce unwarranted variation and improve quality.

METHODS

Multidisciplinary expert consensus and modified Delphi approach. Source documents were workflow algorithms from Kaiser Permanente Northern California and Cancer Care of Ontario based on the 2015 American Thyroid Association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer.

RESULTS

A consensus-based, unified preoperative, perioperative, and postoperative workflow was developed for North American use. Twenty-one panelists achieved consensus on 16 statements about workflow-embedded process and outcomes metrics addressing safety, access, appropriateness, efficiency, effectiveness, and patient centeredness of care.

CONCLUSION

A panel of Canadian and United States experts achieved consensus on workflows and quality metric statements to help reduce unwarranted variation in care, improving overall quality of care for patients diagnosed with thyroid nodules.

THYROID NODULE LOCATION ON ULTRASONOGRAPHY AS A PREDICTOR OF MALIGNANCY

OBJECTIVE

The diagnostic capacity of ultrasonography (US) for differentiating between malignant and benign thyroid nodules is crucial in preventing unnecessary invasive procedures. This is the first study to evaluate whether thyroid nodule location on US has predictive value for malignancy.

METHODS

We retrospectively reviewed data from 219 patients with thyroid nodules who underwent fine-needle aspiration biopsy in 1 year. Patients' demographics as well as nodule's laterality, polarity, morphology, and multinodularity were analyzed. All malignant lesions were confirmed by surgical pathology.

RESULTS

The majority of the patients were female (86.2%). Nodules were evenly distributed between the right lobe (46.3%) and left lobe (49.5%). Eight nodules (4.2%) were located in the isthmus. Most nodules (79.3%) were located in the lower pole, while 9.6% were located in the upper pole and 6.9% in the middle pole. Seventy-five patients (39.9%) had multiple nodules. Fourteen nodules were malignant, representing a prevalence of 7.4%. A significantly higher frequency of malignancy was observed in upper pole (22.2%) compared to lower pole (4.7%) and middle pole (15.4%). A multiple logistic regression model confirmed such association after adjusting for age, body mass index, multinodularity, and laterality. The odds of malignancy in the upper pole were 4 times higher than other locations (odds ratio, 4.6; P = .03).

CONCLUSION

Our study is the first showing that thyroid nodules located in the upper pole can be considered as having higher risk for malignancy. It may enhance the predictive value of malignancy if it is included in thyroid nodule ultrasound classification guidelines.

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists; ATA = American Thyroid Association; BMI = body mass index; FNA = fine-needle aspiration; TMS = total malignancy score; TTW = taller than wide; US = ultrasonography.

Prevalence and associated malignancy of Bethesda category III cytologies of thyroid nodules assigned to the "cytological atypia" or "architectural atypia" groups

OBJECTIVE

To ascertain the prevalence of Bethesda category III cytologies and their malignancy rate, and to analyze differences in the second cytology, malignancy rate, type of carcinoma, and TNM stage between the cytological atypia (CA) and architectural atypia (AA) groups.

PATIENTS AND METHOD

A retrospective study of 973 biopsies. Bethesda category III cytologies were classified as CA when nuclear atypia was seen but they were not diagnostic or suspicious of malignancy, and as AA when smears had few cells but had a predominantly microfollicular pattern and minimal or absent colloid. The cytological and pathological results were correlated.

RESULTS

There were 87 (8.9%) Bethesda category III cytologies (34 CC, 53 AA). Second cytologies were performed in 23 patients (16 with CA, 7 with AA), and a benign result was found in 68.7% of CA and 71.4% of the AA group. Sixty-four patients (23 CA, 41 AA) underwent surgery and 15 of these (23.4%) had a malignant disease: 39.1% CA vs 14.6% AA (P=.029). There was a false negative result in the CA group. The follicular variant of papillary thyroid carcinoma was the most common malignancy (60%). There were no differences in type of carcinoma or TNM stage between CA and AA patients.

CONCLUSIONS

The reported prevalence of Bethesda category III cytologies was as expected. The malignancy rate was significantly higher in the CA group, but there were no differences in the result of the second cytology, type of carcinoma found, or TNM stage. The division of Bethesda category III cytologies is useful to provide a better stratification of the risk of malignancy.

Percutaneous laser ablation for benign and malignant thyroid diseases

Minimally invasive image-guided thermal ablation is becoming increasingly common as an alternative to surgery for the treatment of benign thyroid nodules. Among the various techniques for thermal ablation, laser ablation (LA) is the least invasive, using the smallest applicators available on the market and enabling extremely precise energy deposition. However, in some cases, multiple laser fibers must be used simultaneously for the treatment of large nodules. In this review, the LA technique is described, and its main clinical applications and results are discussed and illustrated.

The risk of thyroid carcinoma in multinodular goiter compared to solitary thyroid nodules: A retrospective analysis of 600 patients

Background

It is generally believed that multinodular goiter (MNG) is associated with a lower risk of malignancy compared to solitary thyroid nodules (STN). This will be the null hypothesis in this retrospective study and we aim to prove or reject it.

Methods

Medical files and histopathology reports of 600 patients who underwent thyroidectomy over 4-year period were reviewed. Data including patient' age, gender, presentation, ultrasonography, FNAC, surgical procedures, final histopathologic diagnosis and stage of malignant tumors were collected and analyzed. The primary end point was assessment of risk of thyroid carcinoma in patients with MNG compared to those with STN. Secondary endpoints included demographic differences and prognosis.

Results

There were 459 females (76.5%). Mean age was 44.3 ± 14.5 years (range 14-85). After exclusion of 33 patients, 224 (39.5%) had STN and 343 (60.5%) had MNG. The prevalence of thyroid cancer was 41.1% (92/224) in STN compared to 29.2% (100/343) in MNG (Chi-Square = 8.593, p < 0.01). However, on multiple logistic regression analysis this correlation was found insignificant (p = 0.640). Only male gender (p = <0.000005) and preoperative impression of malignancy (p = 0.000082) were significantly associated with thyroid carcinoma.

Conclusion

The risk of thyroid carcinoma in STN and MNG was similar. Male gender was identified as a risk factor for thyroid cancer while age, number and size of nodules were not.

Evaluation and management of thyroid incidentalomas detected prior to the parathyroid surgery

BACKGROUND

We investigated the management of thyroid incidentalomas associated with cases of parathyroid lesions in order to suggest a practical approach to their management from a surgical point of view.

METHODS

639 patients underwent radiological and ultrasound investigation of the thyroid area because of parathyroid disorders and parathyroidectomy and had at least three years of follow-up. All follow-up data for these cases were investigated from the moment the lesion was detected and up to the last report.

RESULTS

Out of 639 cases, incidental or asymptomatic thyroid nodules were found in 179 patients (28%), of which, 22 patients were operated (parathyroidectomy + thyroidectomy) and 157 remained with the nodules. For these patients, the average period of follow-up was 7 years 5 mo. Following the results of the follow-up, 52 patients (33%) were suggested to have surgery of the thyroid gland and 49 were operated (16 total thyroidectomies and 33 hemithyroidectomies). The complications after the second surgery included recurrent laryngeal nerve palsy (n = 3), superior laryngeal nerve palsy (n = 1), permanent hypocalcaemia (n = 8), and surgical damage to the internal jugular vein (n = 1). All complications occurred at the previously operated side of the neck.

CONCLUSION

While surgery remains the management of choice for malignant thyroid incidentalomas, for benign cases, if an asymptomatic thyroid nodule was detected inside the thyroid lobe on the side of planned parathyroidectomy and if the size of the nodule is ˃1.5 cm we suggest combined parathyroidectomy + hemithyroidectomy.

The Bethesda System for Reporting Thyroid Cytopathology Explained for Practitioners: Frequently Asked Questions

BACKGROUND

The recent update of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) is a very important development in the evaluation of thyroid nodules. Clinical experience and scientific literature both show that practitioners performing thyroid fine-needle aspiration are accustomed to basing the clinical management of patients on reports using TBSRTC. Specifically, clinicians are familiar with the percent risk of malignancy corresponding to each TBSRTC diagnostic category (DC), as well as with the respective recommendation for clinical management. However, most clinicians are much less familiar with the specific considerations that lie between a given DC, on the one end, and the respective risk of malignancy and associated management recommendation, on the other end.

SUMMARY

A deeper understanding of the system can enlighten the clinician's thinking about the specific nodule under examination and can guide the decision-making process in a more meaningful way. Such an understanding can only be developed via close two-way communication between cytopathologists and clinicians. Through this type of interaction in the authors' tertiary medical center, recurring issues of particular importance for clinical practice were identified, which are reported here in the form of 16 frequently asked questions posed by the clinician to the cytopathologist.

CONCLUSIONS

For each frequently asked question, an answer is provided based on the literature, the authors' experience, the new version of TBSRTC, and the new World Health Organization classification of tumors of endocrine organs.