Avoidance of unnecessary fine-needle aspiration with the use of the Thyroid Imaging Reporting Data System classification and strain elastography based on The Bethesda System for Reporting Thyroid Cytopathology.

Thyroid fine-needle aspiration (FNA) biopsy has been widely accepted as an accurate and cost-effective tool in the management of thyroid nodules. To avoid unnecessary FNAs and provide appropriate management, patient evaluation should be based on a multidisciplinary approach. For this purpose, the Thyroid Imaging Reporting and Data System (TI-RADS) and strain elastography (SE) were proposed as tools for the risk assessment of malignancy in thyroid nodules. The aim of the present study was to analyze the utility of TI-RADS system and SE, along with FNA, and prospectively evaluate 369 consecutive patients referred for FNA of a thyroid nodule. TI-RADS was tested against The Bethesda System for Reporting Thyroid Cytopathology to determine whether there was an agreement between the two classification systems; statistically, some agreement was observed. Medians of the maximum SE values (E-max) were obtained for benign and malignant FNA results and found to be 1.97 [interquartile range (IQR): 1.87] and 2.8 (IQR: 3.42), respectively (P=0.004). The number of studies investigating the utility of TI-RADS and SE along with TBSRCT is currently limited. Our study demonstrated that a multidisciplinary approach with the use of TI-RADS and SE may mildly improve the management of thyroid nodules.

Oncocytic variant of poorly differentiated thyroid carcinoma: "Is diagnosis possible by fine-needle aspiration?"

Poorly differentiated thyroid carcinoma (PDTC) is a very rare entity, and the diagnosis can be made on histopathology specimens. However, recognition of characteristic features of PDTC is significant on fine-needle aspirations (FNAs) to differentiate this entity from well-differentiated and anaplastic thyroid carcinomas. Here, we present an FNA case concordant with "oncocytic variant of PDTC" and discuss whether definitive diagnosis can be given on FNAs to assess the prognosis in clinically inoperable patients.

New Concept of the Encapsulated Follicular Variant of Papillary Thyroid Carcinoma and Its Impact on the Bethesda System for Reporting Thyroid Cytopathology: A Single-Institute Experience.

BACKGROUND: The encapsulated follicular variant (EFV) of papillary thyroid carcinoma (PTC) is the most discussed entity in thyroid pathology. Recently, the question of whether or not EFV-PTC is a malignant entity has been the subject of renewed discussion in the light of recent molecular and clinical studies. The aim of this study was to analyze the malignancy ratios of each category of the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) if EFV-PTC is no longer considered as a malignant entity. MATERIALS AND METHODS: Data on thyroid fine-needle aspirations (n = 1,886) with surgical follow-up between 1999 and 2014 were studied. EFV-PTC cases constituted 27% (94/343) of the malignant cases. RESULTS: Malignancy ratios were determined as nondiagnostic, benign, atypia/follicular lesion of undetermined significance, suspicious for follicular neoplasm/follicular neoplasm, suspicious for malignancy, and malignant categories of the TBSRTC in 13, 7, 45, 30, 72 and 98%, respectively. If EFV-PTC was not regarded as malignant, malignancy ratios would decrease to 6.5, 6, 30, 10, 48, and 87% for each category in the same order. CONCLUSIONS: The current study showed that the most significant decrease in relative malignancy ratios was seen in the suspicious for follicular neoplasm/follicular neoplasm category (66% relative decrease), but all categories represented a considerable decrease.

Is DOG1 really useful in the diagnosis of salivary gland acinic cell carcinoma? - A DOG1 (clone K9) analysis in fine needle aspiration cell blocks and the review of the literature.

INTRODUCTION: DOG1 is a transmembrane protein originally "discovered on gastrointestinal stromal tumors," works as a calcium-activated chloride channel protein. There is a limited number of studies on the potential usage of this antibody in the diagnosis of salivary gland tumors on routine practice in cell blocks. The aim of this study was to search for the usefulness of K9 clone in oncocytic type tumors and review of the literature. MATERIALS AND METHODS: Sixty-nine fine needle aspiration (FNA) cytologic materials of predominantly oncocytic morphology salivary gland tumors; acinic cell carcinoma (AciCC) (n = 8), adenoid cystic carcinoma (n = 2), pleomorphic adenoma (PA) (n = 22), Warthin tumor (WT) (n = 20), myoepithelioma (ME) (n = 5), benign oncocytoma (BeO) (n = 3), mucoepidermoid carcinoma (MEC) (n = 7), mammary analog salivary gland carcinoma (n = 2) were immunostained with DOG1 (clone K9) stain. RESULTS: Of the 8 AciCCs, 7 were observed apical-luminal positive staining, demonstrating 1-3 + intensity, and involving 40-70% of the tumor cells. One MEC of 7 (14%), 1 ME of 5 (20%), and 4 PA of 22 (18%) showed weak (1+) cytoplasmic granular staining in 5-10% of the tumor cells. Pure oncocytic neoplasms (WT, BeO) showed no expression with DOG1-K9. CONCLUSIONS: FNA is a common tool in the diagnosis and management of salivary gland tumors. DOG1-K9 clone was very useful with a unique staining pattern of apical-luminal positivity in the differential diagnosis of AciCC from other oncocytic salivary gland tumors.