Comparison of EUS-FNA and EUS-FNB for diagnosis of solid pancreatic mass lesions: a meta-analysis of prospective studies.

Objective: To quantitatively compare the diagnostic value of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) in solid pancreatic mass lesions using a systematic evaluation method.Methods: A systematic literature search was conducted on public databases to include studies comparing the diagnostic value of EUS-FNA and EUS-FNB in solid pancreatic mass lesions. The combined effect size was estimated using mean difference (MD) and risk difference (RD) respectively, and the corresponding 95% confidence interval (CI) was calculated.Results: The 12 articles (7 RCTs and 5 cohort studies) met the inclusion criteria of this study. The meta-analysis showed that compared with EUS-FNB, EUS-FNA had lower diagnostic accuracy (RD: -0.08, 95% CI: -0.15, -0.01) and specimen adequacy (RD: -0.08, 95% CI: -0.15, -0.02), while higher required number of needle passes (MD: 0.42, 95% CI: 0.12, 0.73). However, EUS-FNB and EUS-FNA presented similar overall complications (RD: 0.00, 95% CI: -0.01, 0.02) and technical failures (RD: -0.01, 95% CI: -0.02, 0.00), without statistically significant differences.Conclusions: Compared with EUS-FNA, EUS-FNB seems to be a better choice for diagnosing suspected pancreatic lesions.

Performance and safety of diagnostic EUS FNA/FNB and therapeutic ERCP in patients with borderline resectable and locally advanced pancreatic cancer - results from a population-based, prospective cohort study.

Objective: Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS FNA/FNB) and potential endoscopic retrograde cholangiopancreatography (ERCP) for biliary decompression are indicated in patients with pancreatic cancer before initation of primary chemotherapy. This study aims to investigate the performance and safety of these two procedures in patients with borderline resectable (BRPC) or locally advanced pancreatic cancer (LAPC). Methods: Endoscopy and pathology reports, and hospital records of consecutive patients with a radiological diagnosis of BRPC/LAPC included in a population based, protocol-driven study (NORPACT-2) were reviewed. Results: Of 251 patients, 223 (88.9%) underwent EUS-FNA/FNB, and 133 (53%) underwent ERCP. Repeated EUS attempts were performed in 33 (14.8%), eight (3.6%), and four (1.8%) patients. FNA was performed in 155 procedures, FNB in 30, and combined EUS-FNA/FNB in 83. Diagnostic accuracy was 86.1% for first EUS-FNA/FNB. The cumulative diagnostic accuracy for all attempts was 96%. False positive rate for malignancy was 0.9%. Of a total of 149 ERCP procedures, 122 (81.9%) were successful, and 27 (18.1%) were unsuccessful. Success rate of first ERCP attempt was 80.5% (107/133). Sixteen patients (12%) underwent a second attempt with a success rate of 93.8% (15 of 16). Combined EUS and ERCP was performed in 41 patients. Complications occurred in eight procedures (3%) after EUS-FNA/FNB, 23 procedures (15.3%) after ERCP, and four (9.8%) patients after combined EUS-FNA/FNB and ERCP. Conclusion: EUS-FNA/FNB and ERCP with biliary stenting in patients with BRPC/LAPC demonstrated acceptable performance and safety. Repeat procedures were performed with high success rates. Same session EUS-FNA/FNB and ERCP for biliary decompression is safe.

The advent of the first electric driven EUS-guided 17 gauge core needle biopsy - A pilot study on subepithelial lesions.

BACKGROUND AND AIMS: This pilot study aimed to evaluate safety and tissue sampling from subepithelial lesions (SEL) in the upper gastrointestinal tract with a novel electric motor driven endoscopic ultrasonography (EUS)-guided 17-gauge (G) size core needle biopsy (CNB) instrument. METHODS: An investigator-led prospective open label, performance and safety control study, including seven patients (female n = 4, median 71 y, range 28-75) with a determined SEL (median size 30 mm, range 17-150 mm) in the upper digestive tract (stomach n = 6, duodenum n = 1) were eligible and later followed up 14 days after index procedure. All investigations were completed according to protocol with three FNB 22-G passes with four fanning strokes and two EndoDrill® 17-G passes with three fanning strokes. RESULTS: Quality of samples as 'visible pieces' (>5 mm): FNB (n = 5/7) (fragmented/blood imbibed n = 1, poor tissue quantity n = 1) compared with 17-G CNB (n = 7/7). Histological result which led to final diagnosis (leiomyoma n = 2, adenocarcinoma n = 1, schwannoma n = 1, neuroendocrine tumour n = 1, desmoid tumour n = 1 and gastrointestinal stromal tumour (GIST) n = 1) could be obtained with the 17-G CNB instrument in all seven patients. FNB technique reached correct diagnosis in six patients. No serious adverse event were recorded. CONCLUSIONS: By using an electric driven 17-G biopsy device, a true cylinder of core tissue can be obtained in one single puncture from the area of interest reducing the need for a second sampling. The absolute benefit of EUS-guided CNB is that the sample can be handled and histologically prepared in the same manner as standard percutaneous core needle sample, e.g., breast and prostate cancer.

The yield of cytology and histology obtained by endoscopic ultrasound-guided fine needle aspiration and biopsy needles in the diagnosis of pancreatic adenocarcinoma.

INTRODUCTION: Endoscopic ultrasound-guided fine needle aspiration and biopsy (EUS-FNA, -FNB) are the mainstay for tissue diagnosis of pancreatic lesions. Traditionally, FNA was performed for obtaining cytology and also histology if available from the puncture. Since their advent, however, FNB needles have been intended mainly to obtain core biopsies for histological specimens. AIMS: We aimed to assess the yield of cytology obtained via both FNA and FNB needles. METHODS: A retrospective study was performed including all patients who were diagnosed with pancreatic adenocarcinoma obtained via EUS-FNA/FNB needles. RESULTS: Overall, 227 patients were included. Of them, 85 patients underwent FNB, versus 142 patients who had FNA. The average age in the FNB group was 70.46 ± 11.29 years, versus 71.44 ± 11.80 in the FNA group, P = 0.57. Notably, cytological analysis diagnosed malignancy equally in both groups (69.4% in the FNB group, vs. 65.5% in the FNA group). The compatibility rate of cytology with histology was 76.5% in the FNB group, versus 76.1% in the FNA group (P = 0.69). The agreement level between cytology obtained by FNA and FNB, versus histology obtained by both needles, was moderate (kappa = 0.48, 95% CI 0.39-0.57). Similarly, the agreement level between cytology and histology in the FNB group was moderate as well (kappa = 0.5, 95% CI 0.36-0.64). CONCLUSION: Cytological assessment yielded an equal performance as compared to histological assessment with both needles. We recommend obtaining cytology specimens in pancreatic solid lesion puncture by FNB needle.

Diagnostic significance and cytological features of NUT carcinoma by EBUS-FNA, a case report and literature review.

Cytomorphological features of NUT carcinoma include sheets or discrete nests of primitive, monotonous, round to oval shaped tumour cells with high N/C ratio and brisk mitotic figures. Abrupt squamous differentiation might be a diagnostic hint. More than 50% positivity of NUT immunohistochemistry staining is diagnostic. NUT carcinoma represents a poorly differentiated malignancy by extremely aggressive clinical course and poor prognosis. It frequently manifests in midline organs, notably in the mediastinum and lung. The rising preferences for utilizing the EBUS-FNA procedure in diagnosing thoracic and lung lesions stems from its high diagnostic yield. Hence, recognizing the cytomorphological features of NUT carcinoma is crucial for timely treatment and improved patient survival.

Small biopsies for pancreatic lesions: Is there still room for fine needle aspiration?

Pancreatic carcinoma is an aggressive tumour with increasing incidence in both sexes worldwide. Early detection is, therefore, essential for patient management. A recent advancement involves the utilization of larger, thicker gauge needles, which enable the collection of core-type biopsies (FNB). Here, we investigated the role of fine needle aspiration and cytopathology in the diagnostic workflow of pancreatic lesions. A search query was designed to search for articles in the PubMed database comparing FNA and FNB for biopsy of pancreatic lesions, and detailed data were extracted from selected studies. Statistical analyses were performed using the R package meta version 6.2. Twenty-one studies made the final cut for data extraction. Overall, median age was 64.3 years (±6.1; 47.6-71.5), male: female proportion 53.9 (±11.3; 27.6-67.4), lesion size 3.1 cm (±0.5; 1.9-4.2 cm) and percentage of malignant cases 78.3% (±26.8; 2.1-100). FNA and FNB diagnostic yield was 85.8% (±10.3; 70.0-100.0) and 89.2% (±7.7; 70.0-98.6), respectively. Average accuracy was 89.5% (±11.7; 63.0-100.0) for FNA and 90.8% (±7.1; 77.0-100.0) for FNB. Adverse effects rate was 1.0% (±1.3; 0-4.3) for FNA and 2.2% (±4.4; 0-16.1) for FNB. None of the selected variables had a significant statistical difference between both methods. FNA and FNB perform similarly for diagnostic material acquisition in pancreatic lesions. The best outcome comes from the association of both techniques, emphasizing the value of combining cytological and histological morphology for the most accurate analysis.

Molecular testing in salivary gland cytopathology: A practical overview in conjunction with the Milan system.

Recently, significant advances in the molecular characterization of salivary gland neoplasms have facilitated the classification and diagnosis of specific diagnostic entities. In the highly challenging diagnostic scenario of salivary malignancies, molecular testing is increasingly being adopted in routine practice to refine the cytological diagnosis of salivary lesions. Here, we reviewed the most recent evidence in the field of salivary glands molecular cytopathology.

The evolving role of interventional cytopathology from thyroid FNA to NGS: Lessons learned at Federico II University of Naples.

Fine-needle aspiration (FNA) guided by ultrasound (US) has emerged as a highly precise diagnostic method for managing thyroid nodules, significantly diminishing unnecessary surgeries. The effectiveness of US-guided FNA is high when a single specialist performs the FNA procedure and the microscopy. This paradigm has paved the way for the evolution of interventional cytopathology, a specialist with a pivotal role in the preoperative diagnostic process, encompassing patient history review, clinical examination, FNA execution under US guidance, preparation, and microscopic interpretation of cytological samples. As the landscape of precision medicine unfolds, molecular testing assumes greater importance in thyroid cytopathology, particularly in refining the risk of malignancy for indeterminate nodules. The updated Bethesda classification system underscores the clinical significance of molecular tests, emphasizing their role in refining diagnostic accuracy. With this evolving landscape, interventional cytopathologists must adapt by acquiring expertise in molecular technologies and addressing ongoing challenges in workflow harmonization and optimization. This paper delves into our decade-long experience as interventional cytopathologists, focusing on recent endeavours to ensure adequate samples not only for microscopic diagnosis but also for molecular testing. Additionally, here we review the challenges of integrating next-generation sequencing (NGS) technology into clinical practice, highlighting the importance of integrating clinically meaningful molecular data into comprehensive molecular cytology reports.

Rapid molecular profiling utilising minimal quantities of endobronchial ultrasound-guided aspirates for the detection of Epidermal Growth Factor Receptor, KRAS, ALK, ROS1, RET, NTRK and MET gene alterations from patients with non-small-cell lung carcinomas on the Biocartis Idylla™ platform.

OBJECTIVES: Comprehensive molecular analysis for patients with non-small-cell lung carcinoma (NSCLC) is essential for managing modern targeted therapies. This study sought to establish the feasibility of utilising real-time PCR to perform rapid and comprehensive profiling on minimal amounts of endobronchial ultrasound-guided (EBUS) aspirates as a fast, tissue-sparing route of predictive profiling. METHODS: A volume of 500 µL of EBUS aspirate and fixative from patients with NSCLC was decanted, and 80 µL (<1% of total specimen received) was utilised for analysis. Biocartis Idylla™ cartridges for epidermal growth factor receptor (EGFR) mutations, KRAS mutations and a GeneFusion cartridge (ALK, ROS1, RET, NTRK1/2/3 rearrangements & MET 14 exon skipping) were analysed for each case to provide molecular data on the main clinically relevant targets as per UK guidelines. RESULTS: A total of 62 cases were included; all of which had successful DNA analysis (EGFR and KRAS cartridges). RNA analysis (GeneFusion cartridge) was successful for 42 of 51 (82%) with initial approach, with 11 of 11 (100%) achieving a successful result with modified protocol. In all, 23 KRAS mutations (37%), 5 EGFR mutations (8%) and 1 ROS fusion (2%) were identified. Average time from specimen receipt to molecular read-out was 5 h. CONCLUSION: Real-time PCR utilising the Idylla™ platform is rapid, utilises minimal amounts of tissue and provides accurate results. We propose this is a useful ancillary method to utilise alongside next-generation sequencing (NGS) in cases of urgent clinical requirement or EBUS aspirates with inadequate quantities of tissue for NGS.

Oncocytic/Hürthle cell lesions have the same implied risk of neoplasm/malignancy as their follicular counterparts.

INTRODUCTION: There are conflicting results on whether the presence of oncocytes modifies the risk of neoplasm (RON) or malignancy (ROM) for thyroid fine-needle aspirates (FNAs): Atypia of undetermined significance AUS and Follicular Neoplasm, FN, or Oncocytic Neoplasm, ON. To our knowledge, the effect of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) has not yet been studied. We compared RON and ROM between follicular type AUS (AUS-FT) and oncocytic type AUS (AUS-OT) and between FN and ON. MATERIALS AND METHODS: We retrospectively analysed all thyroid FNAs with the diagnostic category of AUS-other or Neoplasm (2005-2015). AUS-FT had predominance of microfollicles and AUS-OT had predominance of oncocytes. Histology follow-up was then reviewed and RON, ROM was then calculated and compared (significant at p < 0.05). We repeated the search for 2018 to evaluate for NIFTP effect. RESULTS: Pre-NIFTP, 859/5063 cases (17%) were AUS-FT, AUS-OT, FN, and ON. Histology follow-up was available for 297 cases (35%). RON was 83/183 (45%) for AUS-FT, 35/76 (46%) for AUS-OT, 15/25 (60%) for FN and 11/13 (85%) for ON. Post-NIFTP, RON was 11/31 (35%) for AUS-FT, 5/8 (63%) for AUS-OT, 1/2 (50%) for FN and 4/5 (80%) for ON. For both periods, RON, ROM of AUS-FT was not significantly different than AUS-OT, and no significant differences were observed comparing FN and ON. CONCLUSION: The predominance of oncocytes does not modify the implied RON, ROM for categories of AUS or FN\ON, even after the adoption of NIFTP.

Endoscopic ultrasound-guided bite-on-bite biopsy and endoscopic ultrasound-guided fine-needle aspiration in the diagnosis of gastric tumors with negative malignant endoscopy biopsies: a retrospective cohort study.

BACKGROUND: Specific types of gastric tumors, including gastric linitis plastica and lymphoma, may cause extensive deep-layer infiltration, impeding an accurate diagnosis with endoscopic biopsy. This study aims to evaluate the efficacy of endoscopic ultrasound (EUS)-guided bite-on-bite biopsy and EUS-guided fine-needle aspiration (EUS-FNA) in diagnosing gastric malignancies with negative endoscopic biopsies. METHODS: We retrospectively analyzed suspicious malignant gastric lesion cases in our hospital from October 2017 to August 2023. Clinical manifestations, radiographical examinations, endoscopic examinations, histopathological results, and therapeutic strategies were recorded and analyzed. RESULTS: Forty malignant gastric tumor cases with negative endoscopic biopsies were incorporated into our study. EUS-guided bite-on-bite biopsy was performed in 16 cases exclusively, whereas 17 patients received EUS-FNA exclusively, and seven patients underwent both simultaneously. Among the 23 patients who received the EUS-guided bite-on-bite biopsy, 22 (95.7%) were diagnosed with malignancies. Among the 24 patients who received EUS-FNA, a total of 19 cases with malignancies (79.2%) were confirmed by EUS-FNA (p = 0.11): 13 gastric adenocarcinomas, five metastatic malignancies, and one malignant stromal tumor. No adverse events were observed in any of the cases. CONCLUSIONS: EUS-guided bite-on-bite biopsy and EUS-FNA possess their advantages and disadvantages. EUS-guided bite-on-bite biopsy could serve as a reliable diagnostic method for shallow lesions with negative malignant endoscopic biopsies.

NETosis-Inspired Cell Surface-Constrained Framework Nucleic Acids Traps (FNATs) for Cascaded Extracellular Recognition and Cellular Behavior Modulation.

Upon pathogenic stimulation, activated neutrophils release nuclear DNA into the extracellular environment, forming web-like DNA structures known as neutrophil extracellular traps (NETs), which capture and kill bacteria, fungi, and cancer cells. This phenomenon is commonly referred to as NETosis. Inspired by this, we introduce a cell surface-constrained web-like framework nucleic acids traps (FNATs) with programmable extracellular recognition capability and cellular behavior modulation. This approach facilitates dynamic key chemical signaling molecule recognition such as adenosine triphosphate (ATP), which is elevated in the extracellular microenvironment, and triggers FNA self-assembly. This, in turn, leads to in situ tightly interwoven FNAs formation on the cell surface, thereby inhibiting target cell migration. Furthermore, it activates a photosensitizer-capturing switch, chlorin e6 (Ce6), and induces cell self-destruction. This cascade platform provides new potential tools for visualizing dynamic extracellular activities and manipulating cellular behaviors using programmable in situ self-assembling DNA molecular devices.

Assessment of the diagnostic usefulness of liquid-based cytology. The impact of modifications.

The technique of liquid-based cytology (LBC) is of increasing diagnostic value in non-gynecological cytology. The purpose of the present study was to validate modifications to stages of the LBC process and to assess the diagnostic usefulness of the LBC technique. Between May 2021 and January 2022, a total of 484 samples were prepared from routine cytology tests carried out in the Department of Tumor Pathology of The Greater Poland Cancer Center. The material was obtained from fine-needle aspiration biopsies and fluid samples. One hundred cases were selected for the research described in the article. The slides were prepared using the Becton Dickinson Totalys SlidePrep device. Based on the research, it was concluded that predominantly the LBC technique gives better results than a conventional smear because the background, which would otherwise make it difficult to assess preparations, was eliminated. Additionally, in LBC preparations the cellularity was increased, and the cells were arranged in a monolayer system, which improves the image quality. The introduction of modifications to the LBC method facilitated the process of sample preparation, without adversely affecting the quality of the obtained material.

Gross Appearance of Fine Needle Aspiration Smears: Can Adequacy of the Sample be Assessed and Correlated with their Microscopic Cytological Yield.

Background: Fine needle aspiration cytology (FNAC) is a simple procedure that is widely accepted as a first-line investigation. It should ideally be performed near the patient with microscopic assessment for evaluation of adequacy of aspirate. Since this is not always possible, a worthwhile substitute is to assess the gross appearance of the material obtained. This study was aimed to determine the value of this alternative rapid, bed-side approach. Method: This study was carried out in a tertiary care hospital for a duration of 1 year, where 50 cases undergoing FNAC in the out-patient department (OPD) were included. Unstained smears of commonly encountered lesions were photographed and assessed by three independent observers, who graded them into four grades, viz. Grade 1: unlikely to contain diagnostic material. Grade 2: possibly contains diagnostic material. Grade 3: probably contains diagnostic material. Grade 4: material suggesting a specific diagnosis. Results were subsequently compared with the microscopic findings of stained smears. Results: Distribution of the 50 cases between grades 1, 2, 3, and 4 were 5, 6, 17, and 22, respectively. Conclusion: Gross appearances of FNA smears are helpful in predicting the adequacy of the sample and sometimes the final microscopic diagnosis. The cellularity of a sample can be gauged by inspection and sometimes a likely diagnosis can be made. Some lesions show typical gross appearance easily detected by the experienced eye so a likely diagnosis can be predicted prior to microscopic examination. However, near-patient microscopic assessment of FNA specimens for rapid onsite evaluation, if available, should be the preferred mode.

AIns (insulin) type amyloidoma of the extremity diagnosed by fine-needle aspiration.

Amyloid is an extracellular deposition of Congo red positive material which shows apple green birefringence under polarized light. A cytopathologist can uncommonly encounter such cases. Among the reported cases, a fine-needle aspiration (FNA) of amyloid is frequently misinterpreted as acellular nondiagnostic material. We report a case of amyloidoma of the right upper arm in a 68-year-old man with history of renal transplantation for diabetic nephropathy who presented with loss of appetite and weight loss. Physical exam showed a 7 cm hard nodular subcutaneous mass in the right upper arm. FNA yielded abundant acellular, irregular fragments of dense material, which was Congo red positive with apple green birefringence by polarized light, consistent with amyloid. Further subtyping of the amyloid by mass spectrometry, showed AIns (insulin)-type amyloid deposition. After further questioning, the patient admitted to injecting insulin at the same site for many years. Awareness of the cytological features is important for diagnosis. This is especially important when dealing with uncommon sites and without adequate clinical information.

A Cytohistologic Correlation Study of Thyroid Lesions: Evaluation of Diagnostic Accuracy and Pitfalls of Fine Needle Aspiration Cytology.

Background Only about 5% of palpable thyroid nodules are malignant; the rest are entirely benign. In order to reduce the number of unnecessary treatments and properly identify situations that need surgical intervention, it is essential to distinguish between benign and malignant lesions prior to surgery. There exists a "grey zone" in thyroid cytology characterized by a significant decrease in diagnostic accuracy, making it difficult to precisely classify the lesion and leading to discrepancies. Aims and objectives The study aims to accomplish the following objectives: (1) assess the prevalence of thyroid lesions according to age and sex; (2) evaluate the accuracy of the fine needle aspiration cytology (FNAC) in diagnosing thyroid conditions; and (3) investigate the causes of cytohistological discordance within the context of this study. Materials and methods In our five-year study of thyroid lesions, 125 cases were studied for cytohistological correlation. Discrepant and likened FNAs were classified according to the diagnostic findings. A review of the cytological smears and histological sections was conducted. Results The cytological diagnoses were correlated with histopathology in 109 cases (90.83%). A total of 11 cases (09.16%) were discrepant. There were no false positives (FPs). The causes of false negative (FN) diagnoses in our study can be attributed to geographic misses and failure to recognize dual pathologies. Conclusion FNA is a very precise and time-saving technique for the diagnosis and subsequent management of palpable thyroid nodules. Patients having thyroidectomies have a much higher malignant yield, and the frequency of procedures performed on the thyroid is decreased. When FNA interpretation based on strict specimen sufficiency standards is considered along with clinical and imaging findings, the occurrence of FN and FP diagnoses is expected to decrease.

FNA of Meningioma with Rhabdoid Features Presenting as a Lateral Neck Mass.

Primary meningioma at extracranial head and neck sites is uncommon. Since fine needle aspiration (FNA) is often the first line diagnostic modality for the evaluation of masses in the head and neck, extracranial meningiomas can create a significant diagnostic pitfall for FNA. We report a case of meningioma with rhabdoid features and BAP1 loss in a 26-year-old woman, presenting as a large neck mass along the carotid sheath. FNA biopsy of the mass demonstrated a highly cellular specimen with clusters of uniform, epithelioid cells with round to ovoid nuclei and moderate nuclear to cytoplasmic ratio. An extensive immunohistochemical panel performed on cell block sections showed that the tumor cells were weakly EMA positive, progesterone receptor was focally positive, and SSTR2A was diffuse and strongly positive. BAP1 immunohistochemistry showed a diffuse loss of expression in the tumor cells. After the cytologic diagnosis of meningioma, a tissue biopsy was performed, and the diagnosis of meningioma with rhabdoid features and BAP1 loss was confirmed. We also perform a literature review of meningioma cases presenting as a neck mass and evaluated by FNA. Our case highlights the significant diagnostic challenges that can be caused by extracranial meningiomas on FNA and the importance of ancillary studies to avoid diagnostic pitfalls.

Diffuse C-Cells Hyperplasia Is the Source of False Positive Calcitonin Measurement in FNA Washout Fluids of Thyroid Nodules: A Rational Clinical Approach to Avoiding Unnecessary Surgery.

PURPOSE: The FNA-CT is useful for the diagnosis of MTC. The aim of this study was to evaluate the performance of FNA-CT in TNs coexisting with CCH. METHODS: This study retrospectively reviewed the records of 11 patients with TNs submitted to thyroidectomy on the basis of elevated basal and/or stimulated serum CT values, which at histology were not confirmed to be MTC. The results obtained in this group were compared with those of a previously reported group of histologically proven MTC patients submitted to an identical presurgical evaluation. All patients, negative for known mutations in the RET proto-oncogene, were preoperatively submitted to neck ultrasound, FNA-cytology, and FNA-CT. RESULTS: Approximately 6 of 11 patients showed increased (>36 ng/mL, as established in previous studies not involving patients with CCH) FNA-CT. All these patients showed diffuse CCH at histology in the thyroid lobe submitted to FNA; 5 of them were benign at histology, while only one was malignant (papillary thyroid carcinoma, PTC). The remaining 5 of 11 patients had low FNA-CT (<36 ng/mL), and all of them showed only focal CCH in the lobe submitted to FNA; three of them were malignant (2 PTC, 1 follicular carcinoma), while two were benign. CONCLUSIONS: Employing the currently proposed cut-off values, false-positive FNA-CT results may be observed in benign/malignant TNs with coexisting diffuse CCH. FNA-CT must therefore be cautiously used in the diagnostic approach for patients with TNs and a slightly increased basal or stimulated serum CT concentration in order to avoid unnecessary surgery.

Langerhans cell histiocytosis of the suprasellar region: diagnosis based on thyroid cytology.

Langerhans cell histiocytosis (LCH) may present as unifocal disease of the suprasellar region, with symptoms and signs of hypopituitarism, arginine vasopressin deficiency (AVP-D), and weight gain. Transcranial biopsy is necessary to define diagnosis and guide treatment decisions, but it is associated with significant morbidity. We describe a patient with Hashimoto thyroiditis and a single hypothalamic mass in whom LCH diagnosis was made by thyroid fine-needle aspiration cytology (FNAC) performed despite nonspecific findings in thyroid imaging, on the basis of a slightly elevated [18F]-fluorodeoxyglucose (FDG) avidity on PET/CT and volume increase during follow-up.