OBJECTIVE: This study aimed to analyze the malignant probability of thyroid nodules diagnosed as indeterminate cytology, including atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS), and investigate the diagnostic value of combining BRAF V600E gene testing within this classification.
METHODS: We conducted a retrospective analysis of 126 patients who underwent fine-needle aspiration (FNA) examination of thyroid nodules and subsequent surgical treatment at Beijing Haidian Hospital between October 2021 and November 2022. Among them, there were 22 male and 104 female patients, aged between 18 and 75 years old. Surgical pathology results were considered the gold standard for diagnosing the nature of thyroid nodules, evaluating the malignant incidence of cytological results categorized as AUS/FLUS. Fisher\'s exact test and diagnostic test evaluation methods were used to analyze the discriminatory diagnostic efficacy of preoperative FNA combined with BRAF V600E gene testing for papillary thyroid carcinoma (PTC). Statistical analysis was performed using SPSS 22.0 software.
RESULTS: In PTC patients, the BRAF V600E gene mutation rate was 87.93% (102/116). Within the category of FNA results as AUS/FLUS, the proportion of PTC was 60.00% (15/25). The specificity, sensitivity, positive predictive value, and negative predictive value of the BRAF V600E gene mutation in diagnosing PTC within the AUS/FLUS category were 10/10, 6/15, 6/6, and 10/19, respectively. The BRAF V600E gene mutation significantly increased the detection rate of PTC in patients classified under this cytology (P = 0.028, <0.05).
CONCLUSIONS: Preoperative FNA combined with BRAF V600E gene mutation testing significantly enhances the malignant detection rate of thyroid nodules diagnosed cytologically as AUS/FLUS. This combined approach provides a potent tool to improve diagnostic accuracy in this indeterminate classification.

Oral melanomas are the most common oral malignancies in dogs and are characterized by an aggressive nature, invasiveness, and poor prognosis. With biological and genetic similarities to human oral melanomas, they serve as a valuable spontaneous comparative model. Primary cell cultures are widely used in human medicine and, more recently, in veterinary medicine to study tumorigenesis, cancer progression, and innovative therapeutic approaches. This study aims to establish two- and three-dimensional primary cell lines from oral canine melanomas using fine-needle aspiration as a minimally invasive sampling method. For this study, samples were collected from six dogs, represented by four primary oral melanomas and five lymph nodal metastases. The cells were digested to obtain single-cell suspensions, seeded in flasks, or processed with Matrigel® to form organoids. The cell cultures were characterized through flow cytometry using antibodies against Melan-A, PNL2, and Sox-10. This technique offers a minimally invasive means to obtain cell samples, particularly beneficial for patients that are ineligible for surgical procedures, and enables the establishment of in vitro models crucial for comparative studies in mucosal melanoma oncology. To the best of our knowledge, this is the first work establishing neoplastic primary cell cultures via fine-needle aspiration in dogs.

Littoral cell angioma (LCA) is a rare vascular tumor of the spleen that often requires histopathological analysis for diagnosis due to non-specific imaging features. The current approach is either splenectomy or image-guided percutaneous biopsy which carries notable procedure-associated morbidity and limited accuracy. We present a novel case of LCA successfully diagnosed with endoscopic ultrasound fine-needle aspiration biopsy (EUS-FNAB), demonstrating its potential to reduce the morbidity associated with traditional percutaneous biopsy methods. This case highlights EUS-FNAB\'s advantage in minimizing complications and its effectiveness in diagnosing vascular tumors of the spleen, supporting its inclusion in the diagnostic algorithm for splenic lesions. Further cases are encouraged to explore EUS-FNAB\'s role in diagnosing rare vascular tumors such as LCA to establish its efficacy and safety profile.

UNASSIGNED: The superiority of EUS-guided fine-needle biopsy (EUS-FNB) over fine-needle aspiration (FNA) remains controversial. This study aimed to compare the efficacy of FNB and FNA in immunohistochemistry (IHC)-required lesions, including, type 1 autoimmune pancreatitis (AIP), neuroendocrine tumor (NET), mesenchymal tumor, and lymphoma.
UNASSIGNED: In this multicenter study, specimens from all eligible patients who underwent EUS-FNB/FNA with these specific lesions were prospectively evaluated. Demographics, adequacy of specimens for IHC, diagnostic accuracy, and integrity of tissue were analyzed. Subgroup analysis and multivariate logistic regression were also performed to control confounders.
UNASSIGNED: A total of 439 patients were included for analysis. Most lesion types were type 1 AIP (41.69%), followed by NET, mesenchymal tumor, and lymphoma. FNB yielded specimens with better adequacy for IHC (82.41% vs. 66.67%, P < 0.001) and higher diagnostic accuracy (74.37% vs. 55.42%, P < 0.001). The superiority of FNB over FNA in adequacy for IHC (odds ratio, 2.786 [1.515-5.291]) and diagnostic accuracy (odds ratio, 2.793 [1.645-4.808]) remained significant after control of confounders including needle size, lesion site, lesion size, and endoscopists. In subgroup analysis, FNB showed higher diagnostic accuracy in AIP and mesenchymal tumor, whereas no statistically significant difference was observed in NET and lymphoma.
UNASSIGNED: FNB was superior to FNA needles in obtaining tissues with better adequacy and integrity. These results suggest that FNB should be considered a first-line modality in the diagnosis of IHC-required lesions, especially AIP and mesenchymal tumor. However, a randomized controlled trial with larger sample size is needed to further confirm our findings.

Branchial cleft cysts are congenital anomalies that form during fetal development and originate from the second branchial cleft. They typically manifest as painless masses on the side of the neck and can become symptomatic when infected. These cysts can create a cavity that may foster infection and, in rare instances, facilitate the spread of primary tumors. It is unusual to find ectopic thyroid tissue within a brachial cyst and it is even rarer to see papillary thyroid carcinoma developing from this tissue. Whenever physicians find a case of lateral neck cyst containing thyroid neoplasm without a known primary in the thyroid, there is always a confusion about whether it is a case of metastatic disease with an undetected primary tumor, or is a carcinoma originating from ectopic thyroid tissue. This is a case report of a papillary thyroid cancer that was unintentionally discovered inside a branchial cyst. So far, only five cases akin to this have been documented. There was no sign of an underlying primary thyroid tumor after the patient had a complete thyroidectomy and selected neck dissection, according to a comprehensive evaluation. This article touches on the development of thyroid tissue within branchial cysts and discusses the etiology of lateral neck tumors. The outcome for such patients appears to be favorable after cyst excision and total thyroidectomy. This article also emphasizes the importance of doing routine histopathological examinations on surgically removed samples that look benign.

Autoimmune pancreatitis (AIP) is a unique form of chronic pancreatitis with a multifactorial pathogenesis. Historically, it has been classified as type 1 and type 2, according to its clinical and histological features. The diagnosis of AIP is challenging and relies on a combination of clinical, histopathologic, serologic, and imaging characteristics. In the available guidelines, the imaging hallmarks of AIP are based on cross-sectional imaging and cholangiopancreatography retrograde endoscopic findings. Endoscopic ultrasound (EUS) is generally used for pancreatic tissue acquisition to rule out pancreatic cancer and diagnose AIP with limited accuracy. Several papers reported the reliability of EUS for providing informative morphologic features of AIP. Nowadays, the improvement in the resolution of EUS conventional images and the development of new ancillary technologies have further increased the diagnostic yield of EUS: contrast-enhanced EUS and EUS elastography are non-invasive and real-time techniques that strongly support the diagnosis and management of pancreatic diseases. In this review article, we will present the role of conventional EUS and ancillary diagnostic techniques in the diagnosis of AIP to support clinicians and endosonographers in managing this condition.

OBJECTIVE: Fine-needle aspiration (FNA) of ovarian cyst fluid remains useful for certain clinical circumstances despite low sensitivity and potential safety concerns. The current study aimed to reevaluate the performance of ovarian cystic fluid cytology following American College of Obstetricians and Gynecologists guidelines using a single-institution cohort.
METHODS: A total of 507 ovarian cyst FNA cases from 2013 to 2023 were reviewed. Patients\' demographics and clinical and radiologic information were collected through the electronic database. The performance was calculated using corresponding surgical pathology diagnosis as the gold standard.
RESULTS: Overall, cytologic diagnoses were nondiagnostic (ND), negative for malignancy (NFM), atypical (ATY), suspicious for malignancy (SFM), and malignant (M) in 5 (1.0%), 478 (94.3%), 14 (2.7%), 2 (0.4%), and 8 (1.6%) cases, respectively. Among 349 specimens (68.8%) that had a corresponding surgical pathology, the rate of malignancy (including borderline tumors) was 1.2% (4 of 325) in NFM, 72.7% in ATY (8 of 11), and 100% in both SFM (2 of 2) and M (8 of 8) specimens. Considering NFM and ATY as negative results and SFM and M as positive results, overall, the sensitivity of ovarian cystic fluid cytology was 45.4% and the specificity was 100%.
CONCLUSIONS: As an uncommon test, ovarian cystic fluid cytology has moderate sensitivity and high specificity. Despite limitations, ovarian cystic FNA cytology remains a valuable diagnostic tool in certain aspects.

UNASSIGNED: Ultrasound (US)-guided procedures can be used in the evaluation and treatment of neck masses. However, these procedures need to be practiced before being executed on humans. The aim of this study is to evaluate the efficacy of a training program using a gelatin phantom to practice US-guided procedures.
UNASSIGNED: This program included a lecture and practice with a gelatin phantom. We recruited doctors from different hospitals to practice US-guided procedures, including fine-needle aspiration (FNA), core needle biopsy (CNB), percutaneous ethanol injection (PEI), and radiofrequency ablation (RFA). We used a questionnaire with a 5-point scale to evaluate the effectiveness of practicing US-guided procedures under a gelatin phantom.
UNASSIGNED: Forty-four doctors participated, and 37 of them completed the questionnaires. After training, the mean (SD) scores of the doctors were 4.68 (0.47) for \"Satisfaction with this course,\" 4.54 (0.61) for \"Ease in practicing FNA&CNB using the phantom,\" 4.49 (0.61) for \"Ease in practicing PEI using the phantom,\" 4.49 (0.65) for \"Ease in practicing RFA using the phantom,\" and 4.57 (0.55) for \"The course effectively familiarizing participants with US-guided procedures.\" Participants without experience in US examination had higher scores than those with previous US experience, but the difference was not statistically significant.
UNASSIGNED: A combination of lectures and hands-on practice of US-guided procedures using a gelatin phantom is an effective educational method for doctors interested in head and neck US. After the training program, doctors gained a better understanding of the necessary steps and skills required for these procedures. They can correctly insert the instruments into the target lesion and perform different US-guided procedures.

BACKGROUND: Guidelines for thyroid surgery have evolved to reflect advances in medical knowledge and decrease the overdiagnosis of low-risk thyroid cancer. Our goal was to analyze the change made in operative thyroid management and the impact on thyroid cancer diagnosis.
BACKGROUND: Guidelines for thyroid surgery have evolved to reflect advances in medical knowledge and decrease overdiagnosis of low risk thyroid cancer. Our goal was to study the evolution, over a long period, of pre- and postoperative management and the influence on histological cancer diagnosis and, more particularly, microcancer.
METHODS: In this retrospective cohort study, we included 891 consecutive patients who underwent thyroid surgery between 2007 and 2020.
RESULTS: Respectively 305, 290 and 266 patients underwent surgery over the 3 periods of 2007-2010, 2011-2015 and 2016-2020. In all three periods, women represented approximately 70% of the population, and the mean age was 54 years old (range: 67). Most surgeries (90%) involved total thyroidectomies. Over the study period, the proportion of preoperative fine needle aspiration (FNA) increased from 13 to 55%, p < 0,01. Cancer was found in a total of 116 patients: 35 (11%) patients between 2007 and 2010, 50 (17%) between 2011 and 2015 and 32 (12%) between 2016 and 2020 (p = 0.08). For all 3 periods, papillary thyroid cancer (PTC) was the most prevalent, at approximately 80%. The proportion of thyroid cancer > T1a increased significantly from 37% (2011-2015 period) to 81% (2016-2020 period), p = 0.001. Patients treated with radioiodine remained relatively stable (approximately 60%) but were more frequently treated with a low dose of radioiodine (p < 0.01) and recombinant human TSH (p < 0.01). Operative thyroid weight decreased over time in all but the low-risk T1a PTC cases.
CONCLUSIONS: Over a period of 15 years and according to the evolution of recommendations, the care of patients who underwent thyroid surgery changed with the increased use of preoperative FNA. This change came with a decrease in low-risk T1a PTC.

Background: Artificial intelligence (AI) is increasingly being applied in pathology and cytology, showing promising results. We collected a large dataset of whole slide images (WSIs) of thyroid fine-needle aspiration cytology (FNA), incorporating z-stacking, from institutions across the nation to develop an AI model. Methods: We conducted a multicenter retrospective diagnostic accuracy study using thyroid FNA dataset from the Open AI Dataset Project that consists of digitalized images samples collected from 3 university hospitals and 215 Korean institutions through extensive quality check during the case selection, scanning, labeling, and reviewing process. Multiple z-layer images were captured using three different scanners and image patches were extracted from WSIs and resized after focus fusion and color normalization. We pretested six AI models, determining Inception ResNet v2 as the best model using a subset of dataset, and subsequently tested the final model with total datasets. Additionally, we compared the performance of AI and cytopathologists using randomly selected 1031 image patches and reevaluated the cytopathologists\' performance after reference to AI results. Results: A total of 10,332 image patches from 306 thyroid FNAs, comprising 78 malignant (papillary thyroid carcinoma) and 228 benign from 86 institutions were used for the AI training. Inception ResNet v2 achieved highest accuracy of 99.7%, 97.7%, and 94.9% for training, validation, and test dataset, respectively (sensitivity 99.9%, 99.6%, and 100% and specificity 99.6%, 96.4%, and 90.4% for training, validation, and test dataset, respectively). In the comparison between AI and human, AI model showed higher accuracy and specificity than the average expert cytopathologists beyond the two-standard deviation (accuracy 99.71% [95% confidence interval (CI), 99.38-100.00%] vs. 88.91% [95% CI, 86.99-90.83%], sensitivity 99.81% [95% CI, 99.54-100.00%] vs. 87.26% [95% CI, 85.22-89.30%], and specificity 99.61% [95% CI, 99.23-99.99%] vs. 90.58% [95% CI, 88.80-92.36%]). Moreover, after referring to the AI results, the performance of all the experts (accuracy 96%, 95%, and 96%, respectively) and the diagnostic agreement (from 0.64 to 0.84) increased. Conclusions: These results suggest that the application of AI technology to thyroid FNA cytology may improve the diagnostic accuracy as well as intra- and inter-observer variability among pathologists. Further confirmatory research is needed.