Fine Needle Aspiration Research Articles

A Novel Training Model to Improve Diagnostic Accuracy of Cervical Fine-Needle Aspiration.

This study aims to improve the diagnostic yield of cervical fine-needle aspiration (FNA) through training on a novel liver model. Ultrasonography-guided fine-needle aspiration (US-FNA) is crucial for diagnosing head and neck lumps but requires meticulous execution. Limited resources often hinder systematic teaching, making practical models essential for training. Fifteen otorhinolaryngology residents trained using a liver model with inserted Sensorium spheres to simulate cervical masses. The training involved viewing an instructional video, performing US-FNA on the model, and completing pre- and posttraining self-assessments. Performance was evaluated using visual analog scales (VAS), an adapted version of objective structured assessment of ultrasound skills (adapted OSAUS), and timing of procedures. Clinical impact was assessed by comparing diagnostic rates of US-FNA before and after training. Participants reported increased comfort and proficiency in US-FNA techniques posttraining. Adapted OSAUS scores improved significantly for image recognition and both in-plane and out-of-plane techniques. The diagnostic yield of US-FNA in clinical practice increased from 71% to 85%. No significant influence of gender, preferred ultrasound orientation, age, or experience on the learning curve was found. However, male participants showed a more substantial benefit from the training. The liver model effectively enhances US-FNA skills, reflected in improved clinical diagnostic rates. Training on such models should be incorporated into medical education to reduce inconclusive punctures and enhance patient satisfaction. This study demonstrates the feasibility and effectiveness of a cost-efficient, reproducible model for US-FNA training, emphasizing the importance of practical training in medical education.

Description of a New miRNA Signature for the Surgical Management of Thyroid Nodules

Background: The diagnosis of malignant thyroid nodules is mainly based on the fine-needle aspiration biopsy (FNAB). To improve the detection of malignant nodules, different molecular tests have been developed. We present a new molecular signature based on altered miRNA expressions and specific mutations. Methods: This is a prospective non-interventional study, including all Bethesda categories, carried out on an FNAB sampled in suspicious nodule(s) during thyroidectomy. miRNA quantification and mutations detection were performed. The reference diagnosis was the pathological assessment of the surgical specimen. Different classification algorithms were trained with molecular data to correctly classify the samples. Results: A total of 294 samples were recorded and randomly divided in two equal groups. The random forest algorithm showed the highest accuracy and used mostly miRNAs to classify the nodules. The sensitivity and the specificity of our signature were, respectively, 76% and 96%, and the positive and negative predictive values were both 90% (disease prevalence of 30%). Conclusions: We have identified a molecular classifier that combines miRNA expressions with mutations detection. This signature could potentially help clinicians, as complementary to the Bethesda classification, to discriminate indeterminate FNABs.

Modern Thyroid Cancer Diagnosis: A Review of AI-Powered Algorithms for Detection and Classification

Thyroid nodules are one of the most common abnormalities in the thyroid gland, which are often harmless in nature (benign), but in a few unfortunate instances, they may be fatal (malignant). This review explores recent advancements in artificial intelligence (AI) applied to thyroid cancer detection and classification, with a focus on machine learning, deep learning, and image processing techniques. We provide a comprehensive evaluation of AI applications across key imaging modalities—Ultrasonography (USG), Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Single-Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET/CT)—as well as cytopathological analysis using Fine Needle Aspiration Biopsy (FNAB). By critically examining studies on AI-driven preoperative assessments, we highlight improvements in diagnostic accuracy, sensitivity, specificity and efficiency. This review also identifies current limitations in AI applications, including technical challenges and unresolved issues that hinder widespread clinical adoption. Although significant progress has been achieved, the integration of AI in clinical settings remains limited, as AI-based outputs currently serve as supportive tools rather than definitive diagnostic evidence. We discuss the potential of AI to transform thyroid cancer diagnostics by enhancing reliability and accessibility, while addressing the need for further research to develop a unified, robust and clinically trustworthy AI framework for thyroid cancer diagnosis.

Evaluation of Benign and Malignant Cervical Lymphadenopathy: A Comparative Study of Shear Wave Elastography and Grayscale Ultrasound

Abstract Objectives The aim of the study was to evaluate role of shear wave elastography (SWE) using a novel methodology for differentiation of benign and malignant cervical lymph nodes. Methods SWE was performed on 38 patients who presented with cervical lymph adenopathy. Color-coded elasticity maps were obtained, from which the stiffest region of interest (ROI) with a diameter of 2 mm was chosen. Maximum and mean Young's modulus values (Kpa) were calculated in selected 2-mm ROI. Finally, the results were correlated with the fine needle aspiration cytology findings in all patients to assess the diagnostic accuracy, sensitivity, and specificity at a defined cutoff value for distinguishing between benign and malignant lymphadenopathies. Results There were 20 malignant cervical lymph nodes and 18 benign cervical lymph nodes. Malignant nodes showed significantly higher mean Young's modulus value (154.2 ± 46.19 kPa) compared with benign nodes (70.39 ± 30.76 kPa), with a p-value of less than 0.0001. Our findings indicate that the mean Young modulus value within a standardized 2-mm ROI outperformed grayscale ultrasound in terms of diagnostic accuracy (92.1 vs. 78.9%), sensitivity (100 vs. 80%), and specificity (83.3 vs. 77.7%), with the established cutoff values for high diagnostic accuracy indicating malignancy as greater than 92 for mean Young's modulus with an area under the curve of 0.964. Conclusion SWE using a standardized 2-mm ROI provides improved sensitivity and diagnostic accuracy for differentiation of benign and malignant lymph node lesions.

Adequacy of EUS–guided fine-needle aspiration and fine-needle biopsy for next-generation sequencing in pancreatic malignancies: A systematic review and meta-analysis

ABSTRACT Background and Objectives A majority of pancreatic malignancies are unresectable at the time of presentation and require EUS–guided fine-needle aspiration or fine-needle biopsy (EUS-FNA/FNB) for diagnosis. With the advent of precision therapy, there is an increasing need to use EUS-FNA/FNB sample for genetic analysis. Next-generation sequencing (NGS) is a preferred technology to detect genetic mutations with high sensitivity in small specimens. We performed a meta-analysis to evaluate the adequacy of EUS-FNA/FNB for NGS in pancreatic malignancies. Methods PubMed, Embase, Cochrane Library, and Web of Science were searched from database inception to November 11, 2023. The primary outcome was the proportion of sufficient sample acquired by EUS-FNA/FNB in pancreatic malignancies for NGS. Secondary outcomes were the proportion of sufficient sample for NGS in pancreatic ductal adenocarcinoma (PDAC) and the detection rates of mutations in KRAS, TP53, CDKN2A, and SMAD4 and actionable mutations in PDAC. The pooled proportions were calculated using a random-effects model. Potential sources of heterogeneity were investigated with subgroup analyses and meta-regression. Results Twenty studies with 881 samples were included. The pooled adequacy of EUS-FNA/FNB sample for NGS was 89.9% (95% CI, 80.8%–96.7%) in pancreatic malignancies and 92.0% (95% CI, 81.3%–98.8%) in PDAC. Screening sample suitability before NGS testing was associated with lower adequacy in subgroup analysis (79.7% vs. 98.4%, P = 0.001). The pooled prevalences of mutations in KRAS, TP53, CDKN2A, and SMAD4 in PDAC were 87.4% (95% CI, 83.2%–91.2%), 62.6% (95% CI, 53.2%–71.7%), 20.6% (95% CI, 11.9%–30.8%), and 19.4% (95% CI, 11.2%–29.1%), respectively. The pooled prevalence of potentially actionable mutations in PDAC was 14.5% (95% CI, 8.2%–22.0%). Conclusions In the majority of cases, EUS-FNA/FNB can acquire adequate sample for NGS and identify tumor-specific mutations in patients with pancreatic malignancies. Strict pre-analysis screening criteria may negatively impact the sample adequacy and the success rate for NGS.

Intracystic Glucose Measurement for On-Site Differentiation Between Mucinous and Non-Mucinous Pancreatic Cystic Lesions

Background: Pancreatic cystic lesions (PCLs) are frequently detected incidentally and vary from benign to malignant. Accurate differentiation between mucinous (M-PCLs) and non-mucinous PCLs (NM-PCLs) is essential for appropriate management. This study aims to validate the accuracy of on-site glucose measurement using a glucometer with a cut-off of 50 mg/dL for distinguishing M-PCLs from NM-PCLs. Methods: In this prospective multicenter study, conducted at three European academic hospitals, patients who underwent endoscopic ultrasound-guided fine-needle aspiration for PCLs between 2019 and 2020 were included. On-site glucose measurement was performed using a conventional glucometer. Data on demographics, clinical features, EUS findings, and histopathology were collected. Results: Fifty patients were enrolled, with 37 having glucose levels < 50 mg/dL and 13 ≥ 50 mg/dL. M-PCLs were more common in the <50 mg/dL group (81%) compared to the ≥50 mg/dL group (23%, p < 0.001). The median CEA was higher in the <50 mg/dL group (146 ng/mL) than in the ≥50 mg/dL group (3 ng/mL, p = 0.047). On-site glucose testing < 50 mg/dl demonstrated a sensitivity of 93.2%, a specificity of 76.5%, and an accuracy of 89% for detecting M-PCLs with an AUC of 0.74 and an OR of 14.29 (p < 0.001). In comparison, CEA > 192 ng/mL had a sensitivity of 55.6%, a specificity of 87.5%, and an accuracy of 75.8% for M-PCLs, with an AUC of 0.65 and an OR of 4.44. Conclusions: On-site glucose measurement using a glucometer with a cut-off of <50 mg/dL is a highly accurate, rapid, and cost-effective method for differentiating M-PCLs from NM-PCLs. Our results validate the glucose cut-off in a multicentric prospective cohort supporting its integration into standard diagnostic protocols for PCLs.

Unveiling the Malignancy Risk of Surgically Treated Bethesda III Thyroid Nodules: A 10-Year Retrospective Study Comparing Fine-Needle Aspiration Cytology (FNAC) and Histopathology

Unveiling the Malignancy Risk of Surgically Treated Bethesda III Thyroid Nodules: A 10-Year Retrospective Study Comparing Fine-Needle Aspiration Cytology (FNAC) and Histopathology

EUS-guided fine-needle biopsy versus fine-needle aspiration for histopathological evidence for type 1 autoimmune pancreatitis: A single-center retrospective study in China

ABSTRACT Background and Objectives EUS is recommended for guiding pancreatic tissue acquisition in suspected autoimmune pancreatitis (AIP) cases. However, there is a lack of comparative research on the effectiveness between EUS-guided fine-needle aspiration (EUS-FNA) and EUS-guided fine-needle biopsy (EUS-FNB) for diagnosing AIP in China. This study aimed to evaluate the diagnostic accuracy of EUS-guided tissue acquisition (EUS-TA) specifically for type 1 AIP. Methods Between 2010 and 2023, individuals with AIP who received EUS-TA at Changhai Hospital were included in the study. Results A total of 173 patients diagnosed with AIP who underwent EUS-TA were included in the final analysis. Of these, 104 patients (60.1%) received EUS-FNA, and 69 patients (39.9%) underwent EUS-FNB. Sufficient pancreatic tissue samples (>5 cells/high-power field) were obtained in 164 of 173 patients (94.8%), with success rates of 94.2% for EUS-FNA and 95.7% for EUS-FNB (P > 0.05). EUS-FNB exhibited higher rates of reliable level 1 histopathological findings (40.9% vs. 16.3%, P < 0.001) and reliable level 2 histopathological findings (33.3% vs. 12.2%, P < 0.001) compared with EUS-FNA. Furthermore, a higher occurrence of IgG4-positive plasma cell infiltration (>10 cells/high-power field) was observed with EUS-FNB compared with EUS-FNA (74.2% vs. 27.9%, P < 0.001). The multivariate logistic analysis also revealed that EUS-FNA was less effective in obtaining reliable evidence compared with EUS-FNB, as evident in both level 2 (P = 0.002; odds ratio, 0.21; 95% confidence interval, 0.08–0.56) and level 1 (P = 0.001; odds ratio, 0.19; 95% confidence interval, 0.08–0.49) histopathological evidence. Conclusions EUS-FNB demonstrates higher rates of level 1 and level 2 histopathological findings, as well as more abundant IgG4-positive plasma cell infiltration, compared with EUS-FNA.

Bilateral Cystic Endosalpingiosis in Cervical Lymph Nodes Mimicking Metastatic Papillary Thyroid Carcinoma Morphologically on Cytology: A Case Report and Literature Review of Diagnostic Challenges.

The presence of cystic lymph nodes in the neck can present a challenging differential diagnosis, with considerations often including metastatic papillary thyroid carcinoma (PTC), cystic squamous cell carcinoma, and congenital cysts. The cytologic overlap between benign Müllerian inclusions and PTC features adds complexity, especially in unusual locations. A 45-year-old woman with a history of ovarian serous borderline tumor (SBT) and non-invasive Müllerian implants presented with cystic lymphadenopathy in the neck. Imaging revealed multiple suspicious, partially cystic lymph nodes. Fine-needle aspirations (FNA) from two nodes showed moderate cellularity, monolayered epithelial sheets, and nuclear features suggestive of PTC. FNA cytology, thyroglobulin level, and immunocytochemical profile revealed benign Müllerian cells within lymph nodes. Subsequent histologic evaluation of the excised lymph nodes confirmed cystic endosalpingiosis. This case emphasizes the value of comprehensive clinical-pathologic correlation and appropriate ancillary studies in the evaluation of cystic lymphadenopathy. Awareness of benign Müllerian inclusions and their mimicry of metastatic disease is essential for accurate diagnosis and optimal patient management.

Application of Human Papillomavirus-DNA Test on Salivary Gland Fine Needle Aspiration Cytology Samples Confirms the Absence of the Virus in Primary Neoplasms and Demonstrates for the First Time Its Presence in Salivary Intraglandular Cysts.

The correlation between Human Papillomavirus (HPV) and salivary gland neoplasms is still controversial. Data in the literature are conflicting, reporting the presence of the HPV-DNA in a significant percentage of cases or none. We investigated the presence of HPV in a series of salivary gland neoplasms using fine needle aspiration cytology (FNAC) samples to explore its potential oncogenic role in salivary gland tumor development. The study included 66 salivary gland lesions from 65 patients. For all cases, residual cytological material in the needle hub, once direct smears were obtained, was fixed by rinsing the needle in Cytolyt hemolytic and preservative solution (Hologic Inc. Marlborough, MA 01752 USA). The samples fixed in the Cytolyt hemolytic and preservative solution (Hologic Inc. Marlborough, MA 01752 USA) were centrifuged at 252 g, then the sediment was transferred to the Preservcyt solution and used for the detection of HPV-DNA. We found evidence of the presence of HPV in two salivary intraglandular cysts lined by squamous cell epithelium. Furthermore, we also found HPV in three metastatic oropharyngeal squamous cell carcinomas (SCC) located in the parotid gland. Regarding primary salivary gland tumors, the HPV test produced negative results in all cases. HPV testing produced negative results in all primary salivary gland tumors, failing to confirm the potential involvement of HPV infection in the pathogenesis of salivary gland tumors. Instead, the presence of HPV DNA in samples of salivary intraglandular cysts, never reported before, may be an interesting fact, which however requires further evaluation.

Fine Needle Aspiration Cytology of Palpable Head and Neck Masses: A Descriptive Cross-sectional Study

Introduction: Fine needle aspiration cytology is a quick and safe technique done for the initial diagnosis of head and neck region masses. This study aims to assess the utility of fine needle aspiration cytology in head and neck palpable masses. Materials & Methods: A descriptive cross-sectional study was done in the Pathology Department of Kathmandu Medical College from 1st February 2023 to 31st December 2023. All the patients with palpable head and neck lumps were included in the study. A convenience sampling method was used. The data was entered and analyzed using the Statistical Package for Social Science (SPSS) version 22.0 Results: Among 650 fine needle aspiration cytology done during the study period, 184 were from head and neck lesions (28.30%). The mean age of the patient was 35.4 years with female predominance. The most common site was lymph node 85 (46.19%) followed by thyroid 39 (21.19%). Reactive lymphadenitis was the most common cause of lymphadenopathy seen in 41(22.2%) patients and colloid goitre was the most common cause of thyroid swelling seen in 26(14.13%) patients. Conclusions: Fine needle aspiration cytology is a useful and reliable technique for the diagnosis of head and neck mass. It helps to avoid unnecessary surgeries and is recommended and guides the clinician in general clinical management.

Reporting Bone Cytopathology-A Proposal Based on a Single Tertiary Centre Experience.

Fine-needle aspiration cytology (FNAC) from bone lesions has been proven to be a useful diagnostic tool but lacks standardisation. The aim of the study was to evaluate the diagnostic utility of FNAC as a basis to propose and test a reporting system for bone reporting cytopathology. This retrospective study is based on patients with bone lesions, that were approached by cytology at Skåne University Hospital, Sweden between 2015 and 2023. The diagnostic performance was measured by sensitivity, specificity and accuracy analyses. All diagnoses were then distributed in six categories: (I) Non-diagnostic, (II) Benign, (III) Atypia, (IV) Bone neoplasm of uncertain significance, (V) Suspicious for malignancy and (VI) Malignant. The risk of malignancy (ROM) in each category was calculated. The final cohort consisted of 721 cases. Bone cytology was able to differentiate between benign and malignant lesion with a sensitivity of 89% and a specificity of 99%. The overall diagnostic accuracy was 65% but varied significantly among different types of lesions. Within the tested diagnostic categories, the ROM was (I) 48%, (II) 6.7%, (III) 69%, (IV) 28%, (V) 93% and (VI) 100%. FNAC from bone lesions is a sensitive and specific diagnostic tool with high diagnostic accuracy among various tumour types. This study provides valuable insights for the development of a standardised reporting system for bone cytopathology.

TRPS1 Immunohistochemistry in Salivary Gland Neoplasms: Analysis on Cytology Cell Blocks and Surgical Follow-Up Correlation.

In this study we aim to analyze the TRPS1 immunostaining of salivary gland tumors (SGT) on cytology cell blocks and compare the staining pattern on subsequent surgical resections. Malignant SGTs, oncocytomas and basal cell adenomas diagnosed on fine needle aspiration were retrieved from 2019 to 2021 database. Cases with surgical follow-up were selected. TRPS1 staining was performed on cytology cell blocks and surgical specimens. Scoring was interpreted by two pathologists independently. Our cohort comprised of 58 cases: 45 malignant and 13 benign. TRPS1 scoring was interpreted for 44 cytology and 51 surgical cases. 14 cytology cases lacked tumor cells on deeper levels. For 7 cases, surgical blocks were not retrievable. TRPS1 positivity for cytology and surgical cases were 52% and 47% respectively. In the malignant cohort, TRPS1 was positive in 21/32 (66%) cytology cases and 21/43 (56%) surgical cases. All cases of basal cell adenocarcinoma, carcinoma ex pleomorphic adenoma and salivary duct carcinoma were TRPS1 positive on cytology. All cases of adenoid cystic carcinoma and acinic cell carcinoma were TRPS1 positive on surgical resections. In the benign cohort, TRPS1 was positive in 2/12 (17%) cytology cases; however, none of the surgically resected benign cases showed reactivity (0/8). Cytology-surgical correlation of TRPS1 staining was done in 37 cases. We found 21 concordant and 16 discordant cases. Discordance was highest in mucoepidermoid carcinoma. TRPS1 is not an entirely specific marker for breast carcinoma. TRPS1 positivity was noted in a substantial number of salivary gland malignant neoplasms. Cases demonstrating discordance in TRPS1 staining pattern on cytology-surgical correlation warrant further exploration.

Endoscopic Ultrasound-Guided Pancreatic Tissue Sampling: Lesion Assessment, Needles, and Techniques

Endoscopic ultrasound (EUS)-guided tissue sampling includes the techniques of fine needle aspiration (FNA) and fine needle biopsy (FNB), and both procedures have revolutionized specimen collection from the gastrointestinal tract, especially from remote/inaccessible organs. EUS-FNB has replaced FNA as the procedure of choice for tissue acquisition in solid pancreatic lesions (SPLs) across various society guidelines. FNB specimens provide a larger histological tissue core (preserving tissue architecture) with fewer needle passes, and this is extremely relevant in today’s era of precision and personalized molecular medicine. Innovations in needle tip design are constantly under development to maximize diagnostic accuracy by enhancing histological sampling capabilities. But, apart from the basic framework of the needle, various other factors play a role that influence diagnostic outcomes, namely, sampling techniques (fanning, aspiration or suction, and number of passes), collection methods, on-site evaluation (rapid, macroscopic, or visual), and specimen processing. The choice taken depends strongly on the endoscopist’s preference, available resources at the disposal, and procedure objectives. Hence, in this review, we explicate in detail the concepts and available literature at our disposal on the topic of EUS-guided pancreatic tissue sampling to best guide any practicing gastroenterologist/endoscopist in a not-to-ideal set-up, which EUS-guided tissue acquisition technique is the “best” for their case to augment their diagnostic outcomes.

Comparing needle types and aspiration techniques in EUS-TA to optimize diagnostic efficacy and specimen quality in patients with pancreatic lesions

PurposeIn solid pancreatic lesions (SPLs), we compared the diagnostic efficacy of a 19G fine-needle aspiration (FNA) needle and a 22G ProCore fine-needle biopsy (FNB) needle, We also compared the specimen quality between the standard suction (SS) technique and heparinized wet-suction (HWS) technique.MethodsAll cases of endoscopic ultrasound-guided tissue acquisition (EUS-TA) by 19G FNA or 22G FNB for SPLs in a single-centre hospital were retrospectively reviewed. The diagnostic yield was compared between the 19G and 22G groups. Univariate and multivariate logistic regression analyses were used to identify optimal factors for a correct histological diagnosis. We also examined tissue integrity, the length of the tissue cores, and the rate of blood cell contamination between the SS and HWS groups.ResultsOne hundred seventy-one and sixty-three patients were included in the comparisons of needle types and suction techniques, respectively. The 19G group had higher histological diagnosis rates compared to the 22G group for the first pass (87.8% vs. 70.4%, p = 0.005), the second pass (82.2% vs. 65.4%, p = 0.012), the first two passes (90.0% vs. 72.8%, p = 0.004), and the final diagnosis (91.1% vs. 79%, p = 0.025). Through macroscopic on-site evaluation, a significantly higher proportion of patients in the 22G group required a third needle pass compared to the 19G group (88.9% vs. 67.8%, p = 0.002). The total procedure time was shorter in the 19G group than in the 22G group (p < 0.001). The HWS group showed superiority over the SS group in terms of the total length of tissue cores (p < 0.001) and the total length of white tissue cores (p = 0.005). The HWS group, compared to the SS group, can enhance the tissue integrity (p = 0.024) and reduce blood cell contamination (p = 0.040) during the first needle pass. There was no significant difference in complication rates between the needle puncture groups (p = 0.770) or the aspiration technique groups (p = 0.654).ConclusionCompared to the 22G FNB needle, endoscopists should consider using the 19G FNA needle when appropriate. Furthermore, the use of the HWS technique for the first pass is recommended to improve specimen quality.

Primary Thyroid Diffuse Large B-Cell Lymphoma: A Case Report.

Primary thyroid lymphoma is rare. Hashimoto's disease is usually found as a risk factor. Among thyroid lymphoma, diffuse large B-cell lymphoma (DLBCL) is the most aggressive and frequent one. A 56-year-old man with a medical history of Hashimoto's disease presented with a neck mass and dysphonia. A computed tomography scan revealed a large thyroid mass. Fine-needle aspiration cytology (FNAC) was consistent with lymphoma, confirmed by a core needle as a DLBCL. The patient was transferred to the Department of Hematology and Oncology for chemotherapy with good results. Primary thyroid lymphoma accounts for less than 5% of all thyroid gland malignancies and less than 2% of extranodal lymphomas. It frequently affects women in the sixth or seventh decade. Hashimoto's disease is a major risk factor. DLBCL is the most common histological subtype with aggressive evolution. Radiology and FNAC are not usually very precise and a biopsy is needed. Treatment includes surgery, radiotherapy, chemotherapy, and targeted therapy.

Fine Needle Aspiration Cytological Diagnosis of Primary Breast Large-Cell Neuroendocrine Carcinoma/Squamous Cell Carcinoma.

Primary breast large-cell neuroendocrine carcinoma (LCNEC)/squamous cell carcinoma (SCC), also referred to as mixed neuroendocrine/non-neuroendocrine neoplasms of the breast (Br-MiNENs), represents an exceedingly rare malignancy. We report the first case of primary breast LCNEC/SCC diagnosed via ultrasound-guided fine-needle aspiration (FNA) biopsy of the left supraclavicular and left internal mammary lymph nodes. The patient, a 40-year-old female, underwent a lumpectomy followed by breast-conserving surgery and was diagnosed with primary breast LCNEC. Notably, within merely four months following the breast-conserving surgery, PET-CT revealed lymph node enlargement, prompting the performance of FNA. FNA cytology of metastatic lymph nodes revealed two distinct tumor components, allowing for clear differentiation between LCNEC and SCC in the smear. The diagnosis was further corroborated by immunocytochemical (ICC) staining of the cell blocks. Subsequently, histopathological re-examination of the breast mass revealed occult SCC components comprising less than 1% of the tumor cells. Additionally, the case exhibited triple-negative breast cancer, with PIK3CA, TP53, RB1, and BCL2L11 mutations identified through next-generation sequencing (NGS). Br-MiNEN is exceedingly rare, and its cytological diagnosis poses significant challenges. It is recommended that a detailed and objective description of each tumor component and its proportion be provided. This report provides the first detailed description of the FNA cytology of LCNEC/SCC, thereby enhancing cytopathologists' comprehension of this tumor. Auxiliary studies, including ICC staining and molecular biology assays, are crucial for accurate diagnosis, therapy, and prognosis.

A Prospective Clinical Study to Evaluate the Accuracy of Axillary Lymph Node Staging Using Ultrasound Guided Fine Needle Aspiration Cytology in Breast Cancer Patients

A Prospective Clinical Study to Evaluate the Accuracy of Axillary Lymph Node Staging Using Ultrasound Guided Fine Needle Aspiration Cytology in Breast Cancer Patients

A suspected case of hepatic reactive lymphoid hyperplasia in which EUS–fine needle aspiration contributed to the diagnosis

A suspected case of hepatic reactive lymphoid hyperplasia in which EUS–fine needle aspiration contributed to the diagnosis

The Potential Utility of RAS Q61R Immunohistochemistry as a Screening Tool in Pre-operative Fine Needle Aspirates of Medullary Thyroid Carcinoma.

Medullary thyroid carcinoma (MTC) can either be sporadic, often via mutually exclusive RET or RAS alterations, or inherited via a RET germline alteration. Germline testing is recommended for all patients diagnosed with MTC. RAS p.Q61R immunohistochemistry (RASQ61R-IHC) can identify a subset of RAS-mutated MTCs on resections, but whether this could be applied pre-operatively to cytology specimens remains unclear. Herein, we assessed RASQ61R-IHC in a tri-institutional cohort of cytologic and histologic MTC specimens with available molecular and germline data. Thirty-four fine needle aspirates with cell blocks were identified between three institutions from 2009 to 2024 with corresponding histology. Tumor sequencing and germline data were recorded, if available. RASQ61R-IHC was scored on staining intensity with documentation of membranous accentuation. Sensitivity, specificity, positive predictive (PPV), and negative predictive values (NPV) were calculated. Of the MTCs, 29% were germline-mutated, and 71% were sporadic. Among all sporadic MTCs (n = 22), 41% were RET-altered, 27% were RAS-altered, and 31.8% did not have available data. With any RASQ61R-IHC staining considered positive, sensitivity, specificity, PPV, and NPV for detecting RAS p.Q61R-mutated MTCs were 100%, 72.7%, 45.4%, and 100%, respectively. Requiring a stain score of > 1 and/or membranous accentuation for a true positive changed sensitivity, specificity, PPV, and NPV to 100%, 100%, 100%, and 100%, respectively. RASQ61R-IHC membranous staining was 100% predictive of RET-negative germline testing. RASQ61R-IHC, when requiring a score > 1 and/or membranous stain accentuation for true positive, had high sensitivity and specificity for RAS p.Q61R mutation in cytologic and surgical MTC specimens. Moreover, RASQ61R-IHC is a rapid and inexpensive modality that could potentially tailor which MTC patients undergo germline testing.