Objective To evaluate extrathyroidal extension (ETE) in papillary thyroid microcarcinoma (PTMC) with three-dimensional tomographic ultrasound imaging (3D-TUI). Methods A total of 97 thyroid nodules of 79 patients with PTMC treated in PUMC Hospital from February 2016 to January 2018 were included in this study.Two ultrasound experts performed independent blinded assessment of the relationship between thyroid nodules and thyroid capsule by two-dimensional ultrasound (2D-US) and 3D-TUI.The results of 2D-US and 3D-TUI in evaluating ETE were compared with intraoperative findings and postoperative histological and pathological results. Results Among the 97 nodules,54 (55.7%) nodules had ETE.The diagnostic sensitivity (68.5% vs.37.0%;χ²=10.737,P=0.002),accuracy (74.5% vs.56.7%;χ²=6.686,P=0.015),and area under the receiver operating characteristic curve[0.761 (95%CI=0.677-0.845) vs.0.592 (95%CI=0.504-0.680);Z=3.500,P<0.001] of 3D-TUI were higher than those of 2D-US.However,3D-TUI and 2D-US showed no significant difference in the specificity (84.1% vs.81.4%;χ²=0.081,P=0.776),negative predictive value (67.9% vs.50.7%;χ²=3.645,P=0.066),or positive predictive value (84.1% vs.71.4%;χ²=1.663,P=0.240). Conclusion Compared with 2D-US,3D-TUI demonstrates increased diagnostic efficiency for ETE of PTMC.
Humans ; Thyroid Nodule ; Thyroid Neoplasms/diagnosis* ; Carcinoma, Papillary/pathology* ; Ultrasonography/methods* ; Retrospective Studies

Thyroid nodules are the most common endocrine tumor. Ultrasonography and fine-needle aspiration (FNA) are currently accurate diagnostic tools for evaluating thyroid nodules. However, 10–30% of FNA specimens are cytologically indeterminate. Making an accurate diagnosis between benign and malignant nodules is important so that patients with malignant nodule receive proper treatment and patients with benign nodule can avoid unnecessary treatment. Several genetic changes such as point mutations of the BRAF or RAS and rearrangements of the RET/PTC1, RET/PTC3, PAX8/PPARY are used to adjust to indeterminate FNA. Such a mutational analysis has an excellent positive predictive value (PPV), but there is a weakness in the low negative predictive value (NPV). Gene-expression classifier (GEC) has been found helpful in identify nodules that are benign rather than malignant. GEC has an excellent NPV, but there is a weakness of low PPV. Multiplatform mutational and miRNA test (MPT) and next-generation sequencing assay (NGS) are being studied to compensate for these weaknesses. Molecular tests appear to be a good solution for improving the accuracy of indeterminate FNA cytology specimens and support the clinical management decisions in patients with indeterminate cytologic nodules, but further prospective multicenter trials are required for validation of reported findings and need evaluation of cost-effectiveness. This paper will review recently available molecular diagnostic tools of thyroid nodule.
Biopsy, Fine-Needle ; Diagnosis ; Humans ; MicroRNAs ; Multicenter Studies as Topic ; Pathology, Molecular ; Point Mutation ; Prospective Studies ; Thyroid Gland ; Thyroid Neoplasms ; Thyroid Nodule ; Ultrasonography

We reviewed the current status of thyroid fine-needle aspiration cytology (FNAC) in Korea. Thyroid aspiration biopsy was first introduced in Korea in 1977. Currently, radiologists aspirate the thyroid nodule under the guidance of ultrasonography, and cytologic interpretation is only legally approved when a cytopathologist makes the diagnosis. In 2008, eight thyroid-related societies came together to form the Korean Thyroid Association. The Korean Society for Cytopathology and the endocrine pathology study group of the Korean Society for Pathologists have been updating the cytologic diagnostic guidelines. The Bethesda System for Reporting Thyroid Cytopathology was first introduced in 2009, and has been used by up to 94% of institutions by 2016. The average diagnosis rates are as follows for each category: I (12.4%), II (57.9%), III (10.4%), IV (2.9%), V (3.7%), and VI (12.7%). The malignancy rates in surgical cases are as follows for each category: I (28.7%), II (27.8%), III (50.6%), IV (52.3%), V (90.7%), and VI (100.0%). Liquid-based cytology has been used since 2010, and it was utilized by 68% of institutions in 2016. The categorization of thyroid lesions into “atypia of undetermined significance” or “follicular lesion of undetermined significance” is necessary to draw consensus in our society. Immunocytochemistry for galectin-3 and BRAF is used. Additionally, a molecular test for BRAF in thyroid FNACs is actively used. Core biopsies were performed in only 44% of institutions. Even the institutions that perform core biopsies only perform them for less than 3% of all FNACs. However, only 5% of institutions performed core biopsies up to three times more than FNAC.
Biopsy ; Biopsy, Fine-Needle* ; Biopsy, Needle ; Consensus ; Diagnosis ; Galectin 3 ; Immunohistochemistry ; Korea* ; Pathology ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroid Nodule ; Ultrasonography

Core needle biopsy (CNB) was introduced as an alternative diagnostic tool to fine-needle aspiration (FNA), and is increasingly being used in the preoperative assessment of thyroid nodules. CNB provides a definitive diagnosis in most cases, but it sometimes may be inconclusive. CNB has the advantage of enabling a histologic examination in relation to the surrounding thyroid tissue, immunohistochemistry, and molecular testing that can provide a more accurate assessment than FNA in selected cases. Nevertheless, CNB should be performed only by experienced experts in thyroid interventions to prevent complications because CNB needles are larger in caliber than FNA needles. As recent evidence has accumulated, and with improvements in the technique and devices for thyroid CNB, the Korean Society of Thyroid Radiology released its 2016 thyroid CNB guidelines and the Korean Endocrine Pathology Thyroid Core Needle Biopsy Study Group published a consensus statement on the pathology reporting system for thyroid CNB in 2015. This review presents the current consensus and recommendations regarding thyroid CNB, focusing on indications, complications, and pathologic classification and reporting.
Biopsy, Fine-Needle ; Biopsy, Large-Core Needle* ; Biopsy, Needle ; Classification ; Consensus ; Diagnosis ; Immunohistochemistry ; Needles ; Pathology ; Thyroid Gland* ; Thyroid Nodule*

We report a case of a 74-year-old woman who was incidentally found to have a single thyroid nodule. Laboratory evaluation showed undetectable serum thyroid stimulating hormone and elevated free thyroxine levels. (99m)Tc thyroid scan showed a hyperfunctioning autonomous nodule in a right lobe of the thyroid. Thyroid ultrasonography showed a 2.2 cm sized nonhomogeneous spiculated nodule with microcalcification, and which was identical with the hyperfunctioning nodule confirmed in thyroid scan by (99m)Tc single photon emission computed tomography/computed tomography. Fine needle aspiration was done, and cytology reported as suspicious of malignancy. The patient underwent total thyroidectomy with central neck dissection, and pathology was consistent with papillary thyroid carcinoma. This case report demonstrates that diagnosis of a hyperfunctioning autonomous thyroid nodule does not preclude the possibility of thyroid cancer. Clinicians should consider further evaluation such as ultrasonography and fine needle aspiration in patients with hyperfunctioning autonomous nodules.
Aged ; Biopsy, Fine-Needle ; Diagnosis ; Female ; Humans ; Hyperthyroidism* ; Neck Dissection ; Pathology ; Radionuclide Imaging ; Thyroid Gland* ; Thyroid Neoplasms* ; Thyroid Nodule ; Thyroidectomy ; Thyrotropin ; Thyroxine ; Ultrasonography

BACKGROUNDSome ultrasonographic (US) signs overlap between benign and malignant nodules. The purpose of this study was to raise a special US sign of benign thyroid nodules, termed the "onion skin-liked sign."

METHODSTwenty-seven patients with 27 nodules who shrank naturally and the "onion skin-liked sign" appeared on the final US images were enrolled in the study. The ultrasound characters and risk stratifications at the start and end of observation were compared. Then, thirty goiters with fibrosis and thirty papillary thyroid carcinomas (PTC) were randomly selected from the database of our hospital, matched the sizes of 27 nodules at the end point of observation. The differences of "onion skin-liked sign" between the two groups were analyzed.

RESULTSThe average duration of follow-up of 27 nodules was 24.0 ± 12.2 months (range, 12-65 months). At the end of the follow-up, the size of the nodules decreased on average by 1.26 ± 0.82 cm (range, 0.3-3.4 cm) and calcification was found in 21 nodules, compared with only 2 nodules with calcification at the start of the follow-up. In addition, only negligible or no blood flow signal could be detected at the periphery of all the nodules and 100% (27/27) were high suspicion at the end of observation. In matched groups, all PTC showed high suspicion of malignancy, 18/30 (60%) goiters with fibrosis were high suspicion and 11/30 (37%) were intermediate suspicion. Twenty-two patients in the group of nodular fibrosis presented "onion skin-liked sign," which was not shown in any patient of PTC group. The sensitivity, specificity, positive predictive value, and negative predictive value of "onion skin-liked sign" in predicting nodular goiter with fibrosis were 73.3%, 100%, 100%, and 78.9%, respectively.

CONCLUSIONSThe "onion skin-liked sign" was a characteristic US feature of benign thyroid nodules detected in the follow-up of thyroid nodules. It is useful to differentiate PTCs and nodular goiters with fibrosis.

Adult ; Aged ; Carcinoma, Papillary ; diagnosis ; Female ; Goiter, Nodular ; diagnosis ; Humans ; Male ; Middle Aged ; Thyroid Gland ; pathology ; Thyroid Nodule ; pathology ; Ultrasonography ; methods

PURPOSE: The goal of this study was to evaluate the clinicopathological and imaging features of thyroid nodules surgically diagnosed as hyaline trabecular tumor (HTT), and to assess the role of cytology and frozen sections (FS) in the diagnosis of HTT. METHODS: This study included 21 thyroid nodules in 21 patients treated from August 2005 to March 2015 (mean age, 53.3 years) who were either diagnosed as HTT or had HTT suggested as a possible diagnosis based on cytology, FS, or the final pathology report. Patients' medical records were retrospectively reviewed for cytopathologic results and outcomes during the course of follow-up. Sonograms were reviewed and categorized. RESULTS: Twelve nodules from 12 patients were surgically confirmed as HTT. Ultrasonography (US)-guided fine needle aspiration (FNA) was performed on 11 nodules, of which six (54.5%) were papillary thyroid carcinoma (PTC) or suspicious for PTC and three (27.3%) were HTT or suspicious for HTT. Intraoperative FS suggested the possibility of HTT in seven nodules, of which four (57.1%) were confirmed as HTT. US-FNA suggested the diagnosis of HTT in 10 nodules, of which three (30.0%) were confirmed as HTT. Common US features of the 12 pathologically confirmed cases of HTT were hypoechogenicity or marked hypoechogenicity (83.4%), absence of calcifications (91.7%), parallel shape (100.0%), presence of vascularity (75.0%), and probable benignity (58.3%). CONCLUSION: HTT should be included in the differential diagnosis of solid tumors with hypoechogenicity or marked hypoechogenicity and otherwise benign US features that have been diagnosed as PTC through cytology.
Biopsy, Fine-Needle ; Diagnosis* ; Diagnosis, Differential ; Follow-Up Studies ; Frozen Sections* ; Humans ; Hyalin* ; Medical Records ; Pathology ; Retrospective Studies ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroid Nodule ; Ultrasonography*

In recent years throughout Korea, the use of ultrasound-guided core needle biopsy (CNB) has become common for the preoperative diagnosis of thyroid nodules. However, there is no consensus on the pathology reporting system for thyroid CNB. The Korean Endocrine Pathology Thyroid Core Needle Biopsy Study Group held a conference on thyroid CNB pathology and developed guidelines through contributions from the participants. This article discusses the outcome of the discussions that led to a consensus on the pathology reporting of thyroid CNB.
Biopsy, Large-Core Needle* ; Consensus ; Diagnosis ; Image-Guided Biopsy ; Korea ; Pathology* ; Preoperative Period ; Thyroid Gland* ; Thyroid Nodule

BACKGROUND: The Bethesda System for Reporting Thyroid Cytopathology (BSRTC) uses six diagnostic categories to standardize communication of thyroid fine-needle aspiration (FNA) interpretations between clinicians and cytopathologists. Since several studies have questioned the diagnostic accuracy of this system, we examined its accuracy in our hospital. METHODS: We calculated the incidences and malignancy rates of each diagnostic category in the BSRTC for 1,730 FNAs that were interpreted by four cytopathologists in Gangnam Severance Hospital between October 1, 2011, and December 31, 2011. RESULTS: The diagnostic incidences of categories I-VI were as follows: 13.3%, 40.6%, 9.1%, 0.4%, 19.3%, and 17.3%, respectively. Similarly, the malignancy rates of these categories were as follows: 35.3%, 5.6%, 69.0%, 50.0%, 98.7%, and 98.9%, respectively. In categories II, V, and VI, there were no statistically significant differences in the ranges of the malignancy rates among the four cytopathologists. However, there were significant differences in the ranges for categories I and III. CONCLUSIONS: Our findings suggest that institutions that use the BSRTC should regularly update their diagnostic criteria. We also propose that institutions issue an annual report of incidences and malignancy rates to help other clinicians improve the case management of patients with thyroid nodules.
Biopsy, Fine-Needle ; Case Management ; Diagnosis* ; Humans ; Incidence* ; Pathology ; Thyroid Gland* ; Thyroid Nodule

Metastasis to the primary thyroid carcinoma is extremely rare. We report here a case of colonic adenocarcinoma metastasis to medullary thyroid carcinoma in a 53-yr old man with a history of colon cancer. He showed a nodular lesion, suggesting malignancy in the thyroid gland, in a follow-up examination after colon cancer surgery. Fine needle aspiration biopsy (FNAB) of the thyroid gland showed tumor cell clusters, which was suspected to be medullary thyroid carcinoma (MTC). The patient underwent a total thyroidectomy. Using several specific immunohistochemical stains, the patient was diagnosed with colonic adenocarcinoma metastasis to MTC. To the best of our knowledge, the present patient is the first case of colonic adenocarcinoma metastasizing to MTC. Although tumor-tumor metastasis to primary thyroid carcinoma is very rare, we still should consider metastasis to the thyroid gland, when a patient with a history of other malignancy presents with a new thyroid finding.
Adenocarcinoma/pathology/surgery ; Biopsy, Fine-Needle ; Carcinoma, Medullary/diagnosis/radiography/*secondary ; Colonic Neoplasms/*pathology/surgery ; Humans ; Male ; Middle Aged ; Neoplasms, Second Primary/*diagnosis ; Thyroid Gland/pathology ; Thyroid Neoplasms/diagnosis/radiography/*secondary ; Thyroid Nodule/diagnosis