Acta Cytologica最新文献

Introduction: Fine-needle aspiration biopsy (FNAB) is a minimally invasive diagnostic method widely used in the evaluation of lymphadenopathies. However, there are few studies evaluating its applicability in different age groups, especially among the pediatric population. This study aimed to evaluate the cytological findings of lymph nodes FNAB between pediatric and adult patients using the WHO Reporting System for Cytopathology of Lymph Nodes, Spleen.

Methods: This retrospective and observational study included 366 cases of lymph node FNAB collected and analyzed by a single pathological center (the Instituto de Patologia de Araçatuba), Brazil, from January 2016 to December 2024. Cytological diagnoses were categorized using the WHO Reporting System for Cytopathology of Lymph Nodes, Spleen, and Thymus into five categories (inadequate/insufficient, benign, atypical, suspicious for malignancy, and malignant) and correlated with histopathological outcomes, when available. Ancillary techniques and rapid on-site evaluation were not available. Statistical analyses included chi-square and Fisher's exact tests. p < 0.05 was considered statistically significant.

Results: Among the 366 cases, 17 (4.6%) were pediatric and 349 (95.4%) were adult. The most frequent location of the lesions was the head and neck region (79%). Benign cytological diagnoses were significantly more common in children (94.1%), while suspicious for malignancy and malignant results were exclusive to adults (29.3% and 14%, respectively; p = 0.001). Larger lymph nodes (>2 cm) were significantly associated with malignancy (p < 0.0001). Considering the total population, the rates of risk of malignancy (ROM) were 50% for category "insufficient," 32.6% for benign, 82.8% for suspicious, and 97.5% for malignant cases. From each category, 28 (53.8%), 49 (27.7%), 35 (71.4%), and 16 (32.6%) patients were underwent histopathological follow-ups, respectively.

Conclusion: This study, despite the limited pediatric sample, demonstrates that the method is applicable to both pediatric and adult patients, including those outside cancer centers. The calculated ROM was 50% for inadequate, 32.6% for benign, 82.9% for suspicious, and 97.6% for malignant categories. Deviations from WHO reference intervals for inadequate and benign cases may be attributed to the absence of ancillary techniques. Then, two main findings emerged: (i) benign cytological diagnoses predominated in children, while suspicious and malignant results occurred exclusively in adults; and (ii) lymph nodes >2 cm were strongly associated with malignant cytological and histological outcomes.

Introduction: Urine cytology is a noninvasive and widely used approach for the early detection of urothelial carcinoma (UC), but its diagnostic accuracy is limited, particularly for low-grade lesions. This study aimed to develop a novel artificial intelligence (AI)-based framework for risk stratification of UC from whole-slide images (WSIs), offering a promising solution to enhance the diagnostic accuracy of urine cytology.

Methods: A total of 385 urine cytology slides were included and stratified into three diagnostic groups based on cytological evaluation: negative for high-grade urothelial carcinoma (NHGUC), low risk (including atypical urothelial cells and low-grade urothelial carcinoma [LGUC]), and high risk (including suspicious for high-grade urothelial carcinoma and high-grade urothelial carcinoma). Following digitization into WSIs, expert pathologists conducted detailed cell-level annotation. Cell detection and segmentation were performed using RTMDet and DuckNet, and the extracted features were aggregated into slide-level representations for training and evaluation of classification models.

Results: Support vector machine demonstrated the highest overall performance among the classifiers, with an accuracy of 79%, recall of 79%, and a specificity of 90%. The model demonstrated strong classification performance across three risk stratifications. The high-risk group achieved a sensitivity of 73.1% and specificity of 90.2%, while the low-risk group showed a sensitivity of 81.8% and specificity of 89.1%. Precision-recall curves indicated that the NHGUC group achieved the highest average precision, reaching 0.93, followed by the high-risk group at 0.85 and the low-risk group at 0.82. ROC analysis further demonstrated strong discriminative capability for three risk groups, with the area under the curve measured at 0.95 for NHGUC and 0.91 for both the low-risk and High-risk groups.

Conclusion: The proposed AI-assisted framework shows robust and interpretable performance in stratifying UC cytological categories from WSIs. It holds strong potential as a supportive tool in urine cytology, especially in assisting with the diagnosis of high-risk UC cases.

Introduction: Thyroid and salivary gland cytopathology frequently present diagnostic challenges due to complex presentations, overlapping features between benign and malignant conditions, particularly with gray-zone entities and rare pathologies. To address these issues, the 45th European Congress of Cytology (ECC) held a slide seminar focused on challenging cases. This article reviews key findings from the 6 cases discussed, emphasizing the importance of a comprehensive diagnostic approach. The objective of this article was to illustrate the diagnostic challenges of rare thyroid and salivary gland lesions through case presentations, showing the need for a comprehensive, multidisciplinary approach to accurately reach a final diagnosis and steer the patient's management.

Case presentation: The seminar presented cases involving fine-needle aspiration cytology followed by histopathological correlation, molecular and cytogenetic analyses or immunohistochemistry (IHC) markers to elucidate cytomorphological features, differential diagnoses, and final diagnoses of rare cases in thyroid and salivary gland cytopathology. Challenging thyroid cytology cases included differentiating thyroid sarcoidosis from malignancy, identifying intrathyroidal ectopic thymus versus lymphoid neoplasms, and recognizing poorly differentiated thyroid carcinoma initially misinterpreted as a benign follicular neoplasm. Complex salivary gland cases addressed the distinction of basal cell adenocarcinoma from adenoid cystic carcinoma, metastatic SMARCB1-deficient carcinoma diagnosed via IHC and a parotid mass initially identified as a Warthin tumor.

Conclusion: These cases highlight the critical role of integrating cytological, clinical, and histopathological data to navigate the diagnostic complexities of thyroid and salivary gland lesions. A multidisciplinary approach and standardized algorithms are essential for improving diagnostic accuracy and patient outcomes.

Introduction: Thyroid nodules are uncommon in the pediatric population, with a 1-1.7% prevalence. The Bethesda System of Reporting Thyroid Cytopathology (TBSTC) is a well-established thyroid fine needle aspiration (FNA) reporting system. While the TBSTC guides therapy for both adult and pediatric patients, the reported risk of malignancy (ROM) is variable in the literature. The aim of this study was to compare the ROM in pediatric age of <15 with ≥15 years old.

Methods and materials: We searched for patients aged 21 or younger who underwent FNA of thyroid nodules from 2016 to 2021. Data included patient demographics, nodule size, FNA results, molecular results, and surgical pathology follow-up. Patients were divided into two cohorts: 0-14 (<15) and 15-21 (≥15) years old.

Results: 145 nodules from 102 patients (26 cases in <15 and 94 in patients ≥15) were analyzed. Diagnoses and ROM were nondiagnostic (n = 3), benign (108, ROM 50%), atypia of unknown significance (n = 13, ROM 67%), follicular neoplasm (n = 6, ROM 33%), suspicious for malignancy (n = 1, ROM 100%), malignant (n = 14, ROM 100%). No significant differences (p ≥ 0.2) between the age groups were noted. Based on surgical follow-up results, the overall malignancy rate was 8% and 19% for <15 and ≥15 years old groups, respectively.

Conclusion: The ROM for thyroid nodules in the pediatric population is higher than in adults. There appears to be a trend toward a higher overall malignancy rate in patients aged 15-21 compared to those under 15, though this difference is not statistically significant. Further studies with larger patient numbers are required to determine if the ROM differs significantly between these age groups.

Introduction: Primary melanoma of the lung has been considered an extremely rare and highly aggressive malignancy that accounts for 0.01% of all primary lung tumors. Molecular studies, as well as pertinent clinical history, have since brought into question whether these tumors truly represent primary lesions of the lung. The current study evaluates a series of four melanomas of the lung to assess whether primary melanoma of the lung is truly a diagnostic consideration, or if these cases represent metastases of other primary sites.

Methods: The pathology archives at the University of Chicago Medical Center were searched for patients who underwent robotic or endobronchial ultrasound-guided fine needle aspiration from 2018 to 2024. Clinicopathologic data, including demographics, fine needle aspiration results, and follow-up information including molecular studies and surgical resections, were collected from patients' electronic medical record.

Results: In total 15,959 robotic-guided/endobronchial ultrasound-guided FNAs were reviewed, with 2 cases (0.0001%) being metastatic melanoma with no known cutaneous primary after immunohistochemical and molecular studies. Both patients had molecular studies performed. Notable mutations included BRAF, TERT, NRAS, CDKN2A, and NF1, which are frequently seen in cutaneous melanomas. High tumor mutational burden (UV signature with >98 mutations per megabase) was also detected by next-generation sequencing.

Conclusion: Based upon molecular signatures, clinical history, and presumed lack of precursor cell type within the bronchial epithelium, melanomas arising within the lung are most likely metastatic tumors.

Background: Primary oncocytic salivary gland tumors and oncocytic subtypes of traditionally non-oncocytic salivary gland neoplasms are occasionally encountered in fine needle aspiration specimens, biopsies, and resections. Oncocytes are cells, either non-neoplastic or neoplastic, containing increased numbers of mitochondria resulting in cells with abundant eosinophilic cytoplasm and a low N/C ratio. Summary: A broad range of salivary gland tumors can be oncocytic including oncocytoma, Warthin tumor, mucoepidermoid carcinoma, salivary duct carcinoma, and others, especially those tumors where the oncocytic pattern represents a subtype of neoplasm; the oncocytic pattern can create a diagnostic challenge due to marked similarities in the oncocytic pattern of cells. Key Messages: While their microscopic cytologic and histologic features may be similar, these tumors differ intrinsically at the molecular level. Ancillary studies such as immunologic (e.g., androgen receptor for salivary duct carcinoma) and molecular analysis, e.g., FISH for detecting the MAML2 or PLAG1/HMGA2 gene alterations in mucoepidermoid carcinoma and pleomorphic adenoma, respectively, can be used to classify these oncocytic tumors in difficult cases.

Background: This second of two parts review is devoted to the practical aspects of fine needle aspiration biopsy diagnosis of renal oncocytoma and the interesting biology underlying the morphologic transformation of oncocytes.

Summary: In the first section, we describe the most useful cytologic variables for the recognition of oncocytoma since its first cytologic description 44 years ago. The usefulness of the recently introduced cytologic diagnostic category of "low-risk oncocytic neoplasm" is discussed, as well as the known problems of differential diagnosis. The second section deals with the molecular aspects of oncocytes, with special emphasis on correlating it with the peculiar morphology of oncocytic tumors and their less aggressive behavior. First, why does this accumulation of abnormal mitochondria occur, and second, what are the consequences? Regarding oxidative phosphorylation, oncocytes show a dysfunctional respiratory complex that makes them unable to respond adequately to the hypoxia so typical of the neoplastic environment.

Key messages: The low-risk oncocytic neoplasm category is so relevant that they may limit the possibility of an accurate diagnosis in small specimens, such as FNA and core biopsies. However, this must be compatible with the possibility of making a useful diagnosis for the therapeutic management of the patient. Further, we discuss the genes and molecules responsible for mitochondrial dysfunction, and, finally, the molecular differences between sporadic oncocytomas and those associated with a hereditary context.