Precision Medicine with 3D Ultrasound.

Introduction: A 56-year-old woman was referred for thyroid nodules (TNs) found on a carotid ultrasonography (US). Her laboratories showed a normal thyroid stimulation hormone of 1.530 µIU/mL, normal thyroid hormone levels, and her thyroid antibodies were not elevated. Thyroid 2D US showed an isoechoic solid TN with regular margins measuring 12 × 8 × 10 mm (TR3) in the left thyroid lobe. 3D US demonstrated markedly irregular margins. The nodule volume was 0.52 cm3. Based on current American Thyroid Association and American College of Radiology-Thyroid Imaging, Reporting and Data System (ACR-TIRADS) guidelines, her nodule size would not fit the criteria for fine needle aspiration biopsy (FNAB).1,2 However, because of the irregular margins seen on 3D US, FNAB was offered along with repeat US after 6 months. After considering her options, she requested FNAB. She underwent effective US guided FNAB of the left TN and the cytopathology report indicated follicular neoplasm Bethesda category IV. Subsequently, she had follow-up US guided FNAB for molecular testing with the Afirma's gene sequencing classifier (GSC). The report showed GSC suspicious with an NRAS mutation, indicating a 50% malignancy risk. She elected to have left hemithyroidectomy. The final surgical pathology report demonstrated a 12-mm follicular carcinoma. Materials and Methods: In our thyroid clinic, we utilize conventional 2D US and 3D US to evaluate TN for possible FNAB. Laboratory measurements were performed at Labcorp. Informed consent was given by the patient. The 3D image acquisition follows 2D US examination. The first step in 3D US image acquisition is identifying the target nodule utilizing 2D US. Next, the 3D sweep of the target nodule produces a 3D volume data set and observation of 3D-rendered images generated simultaneously from longitudinal, transverse, and coronal views. A 2D US image displays a TN only on one plane in two dimensions, longitudinal or transverse. The saved 3D volume data set can be viewed and manipulated later. We can reconstruct new images from different angles after the study is completed. The 3D image acquisition direction (front to back versus up to down) will create a different display image and volume slice. The examiner can choose the direction of 3D acquisition before 3D sweep. A 2D US image or machine lacks these qualities. Discussion: This case illuminates recent advances in 3D US imaging and demonstrates that this technology may enhance the value of 2D US in diagnosing malignancy. This technology allows the user to create sequential cross-sectional images through the target nodule. The addition of coronal view to the existing 2D US has been an important contributing factor. Several recent publications have reported that 3D US can improve nodule selection criteria for FNAB.3-5 Our clinic has routinely utilized 3D US technology for the past 4 years. We have learned that this new technology can delineate TN borders more clearly. It not only enhances the observation of structures within but also those attached to the thyroid gland. The target nodule can be rotated and viewed from different angles. The margin irregularities of TNs can be viewed with 3D US in small and large nodules equally. We have found that the 3D US shows the irregular margins of malignant TNs to be more pronounced when compared with high-end 2D US systems. In our experience, the vast majority of benign TNs have regular margins on 3D US. Finally, the 3D volume measurement may provide additional information about the size of TNs for longitudinal follow-up of nodules with benign FNAB. The limitations or challenges of using 3D US in general practice include the cost of the ultrasound machine, lack of reimbursement, and the provider's learning curve. Adding 3D/4D technology to current 2D US does provide more detailed information; however, it requires additional time to complete a thyroid US study. 3D US technology might be more suitable for thyroid clinics or endocrine practices with high patient volumes. Conclusion: We conclude that 3D US can enhance observation of TN margin irregularities and potentially improve nodule selection for FNAB.No competing financial interests exist.Runtime of video: 2 hrs 25 mins 12 secs.

A Blinded Randomized Trial Comparing 2 Needle Gauges for Fine-Needle Biopsy of Thyroid Nodules.

OBJECTIVE: To compare diagnostic capability and patient pain between 25-gauge (25G) and 27G needles for ultrasound-guided fine-needle biopsy of thyroid nodules. STUDY DESIGN: Prospective blinded randomized trial. SETTING: Thyroid clinic in otolaryngology practice in a community. METHODS: A prospective randomized blinded trial was conducted on 148 thyroid nodules in 107 patients undergoing ultrasound-guided fine-needle biopsy. Needle gauge was randomized to individual nodule. Patients were blinded to the needle size used. All specimens were assessed via the Bethesda System for Reporting Thyroid Cytopathology and assigned a morphologic quantitative score based on number of thyroid cells and lymphocytes, amount of colloid, and degree of blood/fibrin artifact in each sample. Patient pain experience was scored. A chi-square test was used to compare nondiagnostic rates, and differences in cytologic morphology and pain scores were compared with 2-sample Student t tests. RESULTS: Of the 148 nodules, 77 were biopsied with 25G needles and 71 with 27G needles. Twenty-five percent (19/77) of the samples obtained with 25G needles yielded a nondiagnostic cytology result (Bethesda category 1) as compared with 11% (8/70) in the 27G group (P = .0282; 95% CI, 1.47%-25.97%). On average, samples from 25G needles had a higher blood/fibrin quantitative score (P = .043; 95% CI, -0.64 to -0.010). There were no differences in pain between groups. CONCLUSION: Use of a 27G needle for fine-needle biopsies is not only safe and feasible but desirable and highly recommended, as it yields better diagnostic information.

Pharyngoesophageal diverticula simulating thyroid nodules: An unusual occurrence with unique features.

Pharyngoesophageal diverticula (PED) of the Zenker's and Killian-Jamieson types arise in close proximity to the thyroid gland, and may rarely be confused with a thyroid nodule on ultrasonography. In this brief report, we detail the cytologic, clinical, and radiologic findings of three PED that were thought to be thyroid nodules, and were subjected to fine-needle aspiration (FNA). The patients were females with an age range of 51-64 years. All three patients had multiple thyroid nodules, and two patients reported symptoms attributable to the diverticulum. Nodule sizes ranged from 1.0 to 2.7 cm, and either the right or left thyroid lobe could be involved. Microcalcifications were present by ultrasonography in all three cases. FNA of these thyroid nodule mimics showed squamous cells with granular or amorphous debris, bacterial and/or fungal colonies, inflammation, and food particles. These cytologic features, particularly the presence of vegetable or meat fragments, are characteristic, and have also been reported in the few previous reports of PED. The presence of a diverticulum was confirmed with imaging studies in all our patients. Although a rare occurrence, the inadvertent FNA of a PED masquerading as a thyroid nodule is important to recognize, as a recommendation for appropriate radiologic studies could potentially avoid inappropriate therapy for thyroid disease.

Identification of parathyroid tissue in thyroid fine-needle aspiration: A combined approach using cytology, immunohistochemical, and molecular methods.

OBJECTIVES: Parathyroid (PT) lesions can be difficult to recognize in thyroid fine needle aspirations (FNAs), and when not identified correctly, PT cells may be mistaken for potentially abnormal thyroid cells. We therefore studied the utility of combining cytology, immunohistochemistry, and a molecular classifier to identify PT cells in thyroid FNAs. METHODS: Thyroid FNAs were received in CytoLyt, and were evaluated initially using The Bethesda System for Reporting Thyroid Cytology (TBSRTC). The PT molecular classifier was performed along with the Afirma Gene Expression Classifier (GEC) on samples with indeterminate cytology. Immunohistochemistry (IHC) for PT was performed on all samples using Cellient cell block sections. Clinical and ultrasound information was collected, when available. RESULTS: PT tissue was identified in 60 thyroid FNAs. Forty-seven (47) samples had cytologic features that were suggestive of PT cells, and were subsequently confirmed with IHC. Thirteen (13) samples were not recognized as PT, and were considered to be either Bethesda III or IV indeterminate thyroid nodules; a PT gene expression signature was subsequently detected by the GEC. These samples were also confirmed as PT by IHC. Clinical and ultrasound features were suggestive of a PT lesion in only a third of cases. CONCLUSIONS: Cytologic features, coupled with IHC, can identify intrathyroidal PT cells in the majority of CytoLyt samples. However, a significant minority (22%) of these FNAs may be misclassified as indeterminate by TBSRTC criteria, and molecular detection of the PT tissue can be helpful to potentially avoid an additional biopsy or diagnostic surgery. Diagn. Cytopathol. 2017;45:526-532. © 2017 Wiley Periodicals, Inc.