We compared the diagnostic performances and unnecessary fnA rates of several guidelines and modified versions using the size threshold of the ACR TIRADS. Our Institutional Review Board approved this retrospective study and waived the requirement for informed consent and all methods were performed in accordance with the Declaration of Helsinki. A total of 1,384 thyroid nodules in 1,301 patients with definitive cytopathologic findings were included. US categories were assigned according to each guideline. We applied the size threshold suggested by the ACR TIRADS for FNA to the Kwak, ATA and EU guidelines and defined these modified guidelines as the modified Kwak (mKwak), modified ATA (mATA) and modified EU (mEU) guidelines. Diagnostic performances and unnecessary FNA rates of all guidelines were evaluated. Of 1,384 thyroid nodules, 291 (21%) were malignant. Among the original guidelines, the ACR TIRADS had the highest specificity, accuracy, LR and AUC (62.2%, 66%, 2.128 and 0.713). The mKwak, mATA and mEU guidelines had higher specificity, accuracy, LR and AUC (P < 0.001 for all), and fewer unnecessary FNAs, compared with their original guidelines. Among all original and modified guidelines, the mKwak guideline had the highest specificity, accuracy, LR and AUC (64%, 68.6%, 2.389 and 0.75). The unnecessary FNA rate was the lowest with the mKwak guideline (61.1%). The highest sensitivity was observed with the ATA guideline (98.6%). After incorporating the size threshold of the ACR TIRADS to other TIRADS, all guidelines showed higher diagnostic accuracy and lower unnecessary FNA rates than their original versions. The mKwak guideline showed the best diagnostic performances. Thyroid ultrasonography (US) is now regularly performed in clinical practice and thyroid nodules are exceedingly common on US with as many as 68% of adults having one, leading to issues of overdiagnosis and overtreatment 1,2. Many guidelines recommend fine-needle aspiration (FNA) based on several risk stratification systems which use different US features and even different size thresholds 3-7. Current risk stratification systems using US features can be broadly divided into two types: the point-scale Thyroid Imaging Reporting and Data System (TIRADS) suggested by Kwak et al. 8 , Park et al. 9 and the American College of Radiology (ACR) 3 and the pattern-recognition TIRADS suggested by Horvath et al. 10 , the 2015 American Thyroid Association (ATA) 7 , and European Thyroid Association (EU) 11. Different size criteria have been suggested by the ATA guideline, ACR and EU TIRADS 3,7,11. Although there are many guidelines for recommending FNA for thyroid nodules on US, a worldwide communicable system does not presently exist. Recently, Grani et al. 12 demonstrated that the ACR TIRADS reduced unnecessary FNAs more than other international guidelines with a very low false-negative rate (2.2%, 6/268). The ACR TIRADS suggests a higher size threshold for FNA than other guidelines while still recommending similar malignancy risks for each final assessment ca...

No abstract

No abstract

No abstract

Metaplastic carcinoma is a rare subtype of breast cancer that comprises histologically diverse malignancies. Metaplastic carcinoma tends to have an aggressive clinical presentation, high metastatic potential, and more chances of local recurrence, as compared with intraductal carcinoma. Although many clinical and pathologic finding have been reported, to our knowledge, there are few reports of imaging findings for this type of tumor.In this study, we reviewed data of 5 patients with histopathologically proven metaplastic breast carcinoma. Multimodality imaging findings including those from mammography, ultrasonography, magnetic resonance imaging, and positron emission tomography–computed tomography were recorded.The results indicated that metaplastic carcinomas tend to show more benign imaging features such as round or oval shape with circumscribed margins and less axillary lymph node metastasis compared with invasive ductal carcinoma. High signal intensity on T2-weighted magnetic resonance imaging due to its cystic or necrotic component may be useful for diagnosis of metaplastic carcinoma.