Acta CytologicaPub Date : 2026-10-17DOI: 10.1159/acy/abjag015
Isabella Sorice, Mariantonia Nacchio, Domenica Di Giovanni, Anna Maria Carillo, Gennaro Acanfora, Maria Salatiello, Pasquale Pisapia, Cristina Luongo, Dario Lanzuise, Domenico Salvatore, Elena Vigliar, Giancarlo Troncone, Claudio Bellevicine
{"title":"Does oncocytic morphology affect the performance of a 7-gene mutation panel in Bethesda IV thyroid nodules? A retrospective single-institution study.","authors":"Isabella Sorice, Mariantonia Nacchio, Domenica Di Giovanni, Anna Maria Carillo, Gennaro Acanfora, Maria Salatiello, Pasquale Pisapia, Cristina Luongo, Dario Lanzuise, Domenico Salvatore, Elena Vigliar, Giancarlo Troncone, Claudio Bellevicine","doi":"10.1159/acy/abjag015","DOIUrl":"https://doi.org/10.1159/acy/abjag015","url":null,"abstract":"<p><strong>Background: </strong>Bethesda category IV includes oncocytic (OFN) and non-oncocytic follicular neoplasms (FN). We evaluated whether a 7-gene mutation panel performs differently across these cytomorphologic phenotypes.</p><p><strong>Methods: </strong>We retrospectively reviewed 319 Bethesda IV fine-needle aspirations (2020-2025); cytomorphologic features were assessed in the 285 cases with evaluable 7-gene testing results. Risk of malignancy (ROM) and other diagnostic metrics, including mutation rates and mutation-malignancy association were calculated for FN and OFN.</p><p><strong>Results: </strong>In both FN and OFN we observed RAS-like alterations only. Mutation prevalence was higher in FN (32/112, 28.6%) than in OFN (27/173, 15.6%; OR 2.16, 95% CI 1.21-3.86; p=0.011). In FN, mutation-positive nodules showed a ROM of 50.0% (7/14) vs 14.7% (5/34) in mutation-negative cases (OR 5.80, 95% CI 1.41-23.8; p=0.024). In OFN, ROM was 42.9% (3/7) vs 34.2% (13/38) in mutation-negative cases (OR 1.44, 95% CI 0.28-7.44; p=0.686).</p><p><strong>Conclusions: </strong>A positive 7-gene result was associated with significant risk enrichment in FN, while the association in OFN did not reach significance. The lower mutation prevalence in OFN, together with available evidence that oncocytic tumors are associated with chromosome instability, supports the incorporation of copy number variation analysis as a part of broader panel testing strategy.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149214875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta CytologicaPub Date : 2026-10-13DOI: 10.1159/acy/abjag014
{"title":"Erratum.","authors":"","doi":"10.1159/acy/abjag014","DOIUrl":"https://doi.org/10.1159/acy/abjag014","url":null,"abstract":"<p><p>In the article \"Cytological Features That Improve the Diagnostic Accuracy of Human Papillomavirus-Associated Glandular Lesions in Uterine Cervical Cytology\" [Acta Cytologica. 2026:403-411; https://doi.org/10.1159/000550479] by Atsushi Minoshima et al., reproduced Figure 4 without permission of the copyright holder.The article has therefore been republished with Figure 4 removed.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Prevalence and Diagnostic Performance of the BRAF V600E Mutation in Papillary Thyroid Carcinoma: A Cross-Sectional Study in Uruguay.","authors":"Emilia Moreira, Carolina Sian, Federico Farias, Eugenia Fernández Armúa, Eduardo Osinaga, Nora Berois","doi":"10.1159/acy/abjag013","DOIUrl":"https://doi.org/10.1159/acy/abjag013","url":null,"abstract":"<p><p>Thyroid cancer is the most common endocrine malignancy, and the detection of thyroid nodules has increased with the widespread use of ultrasound. In this context, the BRAF V600E mutation has emerged as an important molecular marker in papillary thyroid carcinoma; however, its prevalence varies geographically and local data remain limited. This study aimed to determine the prevalence of the BRAF V600E mutation in a Uruguayan population and to evaluate its potential role as a complementary diagnostic tool. A cross-sectional analytical study was conducted including 155 patients who underwent fine-needle aspiration (FNA) for thyroid nodules at Maciel Hospital between October 2020 and September 2022). Archived formalin-fixed paraffin-embedded (FFPE) tumor samples were also analyzed to increase the number of histologically confirmed cases. Detection of the BRAF V600E mutation was performed using allele-specific PCR. Clinical, ultrasonographic, cytological (Bethesda classification), and histopathological data were collected from medical records. The prevalence of the BRAF V600E mutation was 75.9% among 29 papillary thyroid carcinomas and only 4/151 benign lesions (2.6%). The assay showed a sensitivity of 73.3% (CI 55.6% - 85.8) and a specificity of 95.4% (IC 90.7% - 97.7%), with a positive predictive value of 75.9% (CI 57.9% - 87.8%) and a negative predictive value of 94.7 (CI 90.0% - 97.3%) Significant associations were observed between the mutation and Bethesda categories V-VI (p < 0.001), hypoechogenicity (p = 0.01) and malignant histopathology (p < 0.001). These findings support the use of BRAF mutation testing may serve as a complementary tool in the diagnostic assessment of thyroid nodules.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149163974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta CytologicaPub Date : 2026-10-10DOI: 10.1159/acy/abjag006
Olivia J Leung, Serena M Walker, Stefen Andrianus, Zubair Baloch
{"title":"Diagnosing Squamous Lesions of Head and Neck: Categorization, Risk of Malignancy, and Follow-Up: An Institutional Experience.","authors":"Olivia J Leung, Serena M Walker, Stefen Andrianus, Zubair Baloch","doi":"10.1159/acy/abjag006","DOIUrl":"10.1159/acy/abjag006","url":null,"abstract":"<p><strong>Introduction: </strong>Fine-needle aspiration (FNA) is essential for evaluating the wide range of squamous lesions that present in the head and neck. In this retrospective study, we reviewed cytology cases from our institution involving squamous lesions of the head and neck region to characterize their diagnostic categorization and evaluate concordance between cytological assessments and corresponding surgical pathology diagnoses.</p><p><strong>Methods: </strong>All in-house and consult head and neck FNA cases containing the term \"squamous\" from September 2021 to September 2024 were reviewed. Electronic medical records were reviewed to extract patient demographics and lesion characteristics, including anatomic site, size, and solid versus cystic composition. Radiological findings and follow-up surgical pathology were also obtained when available.</p><p><strong>Results: </strong>In this study, cytology demonstrated a sensitivity of 99.3%, specificity of 81.8%, positive predictive value of 97.4%, and negative predictive value of 94.7% yielding an overall accuracy of 97.1%. The risk of malignancy (ROM) by cytological category was 66.7% for nondiagnostic/scant, 5.3% for benign, 76.4% for atypical, 100% for suspicious for malignancy, and 96.9% for malignant. Both benign and malignant entities were diagnosed across all anatomic sites and lesion size categories.</p><p><strong>Conclusion: </strong>FNA is a highly effective and reliable method for evaluating squamous lesions of the head and neck with high sensitivity and accuracy. The progressive increase in ROM across diagnostic categories supports the utility of a stratified diagnostic system. Radiological-pathological concordance highlights the strength of a multidisciplinary diagnostic approach, though discrepancies show the limitations of relying on imaging or clinical features alone.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149164091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cytomorphology of Hematolymphoid Neoplasms in Body Cavity Effusions: Diagnostic Value and Prognostic Implications- A case Series.","authors":"Preeti Agarwal, Mamta Dwivedi, Geeta Yadav, Madhu Kumar, Rashmi Kushwaha, Debarati Mitra, Himanshu Mohan, Mitali Rawat, Shailendra Prasad Verma","doi":"10.1159/acy/abjag009","DOIUrl":"https://doi.org/10.1159/acy/abjag009","url":null,"abstract":"<p><strong>Background & objectives: </strong>Involvement of the pleural and peritoneal cavities by hematolymphoid malignancies is relatively infrequent compared to epithelial malignancies, though reported rates vary widely depending on institutional and demographic factors. When present, they may or may not be the first manifestation of disease; however, they usually indicate an advanced stage. Cytological recognition is often challenging due to morphological overlap with reactive processes, yet it remains a valuable, minimally invasive diagnostic tool. This study describes the cytomorphological spectrum, diagnostic contribution, and clinical outcomes of hematolymphoid malignancies detected in effusion cytology, and contextualises findings with published literature.</p><p><strong>Case presentations: </strong>A retrospective review was conducted of all effusion cytology samples reported between August 2024 and August 2025 at a tertiary care centre. Cases demonstrating atypical hematolymphoid cells were analysed for clinical presentation, cytomorphology, and follow-up. A review of published English literature was also undertaken. Four hematolymphoid malignancies were identified, comprising 12.9% (4/31) of malignant effusions and 0.22% (4/1807) of all effusion samples. Cytology was the initial diagnostic clue in two patients: a 16-year-old male with gastric myeloid sarcoma (alive and stable post-chemotherapy) and a 41-year-old male with ileocecal diffuse large B-cell lymphoma (died before treatment). Two additional cases represented follow-up effusions: a 60-year-old female with acute myeloid leukaemia and a 62-year-old male with chronic myeloid leukaemia on imatinib therapy, both of whom died shortly after effusion development. Morphological hallmarks included blasts, atypical lymphoid cells, hand-mirror forms, and immature myeloid elements.</p><p><strong>Conclusion: </strong>Though infrequently positive in hematolymphoid malignancies, effusion cytology can provide pivotal early diagnostic information and guide clinical management. Recognition of subtle cytomorphological features is essential, as effusion involvement typically reflects aggressive disease and adverse outcomes.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149147276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta CytologicaPub Date : 2026-09-30DOI: 10.1159/acy/abjag010
Andrew S Field, Martha B Pitman, Bharat Rekhi, Ian A Cree, Dilani Lokuhetty, Fernando Schmitt
{"title":"WHO Reporting Systems in Cytopathology: a review of Current Status and the Future.","authors":"Andrew S Field, Martha B Pitman, Bharat Rekhi, Ian A Cree, Dilani Lokuhetty, Fernando Schmitt","doi":"10.1159/acy/abjag010","DOIUrl":"https://doi.org/10.1159/acy/abjag010","url":null,"abstract":"<p><p>A joint project of the International Academy of Cytology (IAC), the International Academy for Research into Cancer (IARC) and the World Health Organisation (WHO) has developed eight reporting systems in cytopathology with the WHO Reporting Systems in Lung, Pancreaticobiliary, Lymph node, Thymus and Spleen, and Soft Tissue published between 2022 and 2025, and four further Systems in Breast, Liver, Kidney and Adrenal, and Head and Neck nearing completion. The systems are designed to improve communication between cytopathologists and clinicians by integrating clinical and imaging context with a diagnostic category, cytopathological criteria and ancillary testing. The internationally standardized categories are linked to a hierarchial risk of malignancy, and practical diagnostic management recommendations for cytopathology specimens across organ systems. Key diagnostic cytopathological features for entities have been developed through consensus by the expert editorial boards with global representation, and the Systems emphasize the importance of specific diagnoses and differential diagnoses based on these features. In addition, detailed standardized information is provided on the use whenever available of ancillary testing including pre-analytical handling and preparation of specimens. Practical information on the role of cytopathology and on specimen procurement is provided. The new reporting systems have generated research on their usefulness and accuracy leading to a beneficial focus on cytopathology in various medical resource settings. The development process has highlighted several unresolved challenges, including the role of FNAB versus core needle biopsy, the definition of adequacy, the use of ancillary testing, and the need for standardized cytopathological language. Further research should focus on assessment of the reporting systems through prospective studies in a variety of resource settings to ensure international applicability, utilizing standardized data collection and statistical analysis. The Reporting Systems will need to continue their close correlation with the developing 6th edition of the WHO Tumour Classifications. Key words: fine needle aspiration biopsy cytopathology, WHO Reporting Systems, risk of malignancy, structured reporting.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149102691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta CytologicaPub Date : 2026-09-29DOI: 10.1159/acy/abjag011
Joanna K M Ng, Billy H C Cheung, Esther K C Cheung, Logan T S Tao, Ava Kwong, Joshua Li
{"title":"Cytology of axillary breast carcinoma metastasis with squamous features - a morphological spectrum of diagnostically problematic aspirates.","authors":"Joanna K M Ng, Billy H C Cheung, Esther K C Cheung, Logan T S Tao, Ava Kwong, Joshua Li","doi":"10.1159/acy/abjag011","DOIUrl":"https://doi.org/10.1159/acy/abjag011","url":null,"abstract":"<p><p>Background Fine-needle aspiration cytology of axillary lymph nodes plays an established role in the staging and management of breast cancer. Squamous differentiation in breast carcinomas can be seen in metaplastic carcinomas, primary squamous cell carcinomas and treatment effects. This study reviews a cohort of metastatic breast carcinomas with squamous features in axillary lymph node aspirates. Methods A computerized search of the department pathology archives from 2016 to 2026 was performed for breast specimens with histologic evidence of squamous features matched to axillary lymph node aspirates, and malignant axillary lymph node aspirates with cytologic evidence of squamous features. Slides, reports and clinical information were reviewed. Results A total of 13 axillary lymph node aspirates were retrieved from 12 patients aged 42 to 79 years. Cellularity was variable and glandular clusters were seen in only 1 case. Keratin pearls were present in 6 cases. The majority of histologic correlates were invasive ductal carcinomas (n = 8/12), with histologic squamous differentiation in 6. There were 2 metaplastic carcinomas, 1 mixed ductal/lobular carcinoma with squamous differentiation, and 1 case with complete pathological response. Of 10 cases with biomarker status, 5 were triple-negative, 4 hormone-positive and 1 HER2-overexpressed. Conclusion Squamous morphology in axillary node aspirates should raise suspicion for metastatic breast carcinoma with squamous differentiation. This scenario is prone to gaps across clinical, histological, cytological, and immunocytochemical layers. Careful observation of subtle glandular components, accompanied by review of histological findings and immunocytochemistry, is important for accurate diagnosis.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149079342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta CytologicaPub Date : 2026-09-07DOI: 10.1159/acy/abjag008
Bharat Rekhi, Xiaohua Qian, Andrew S Field
{"title":"Updates on Soft Tissue Cytopathology: Focusing on New and Provisional Entities, Distinct Types, New Diagnostic Tools, and Evolving Concepts.","authors":"Bharat Rekhi, Xiaohua Qian, Andrew S Field","doi":"10.1159/acy/abjag008","DOIUrl":"10.1159/acy/abjag008","url":null,"abstract":"<p><strong>Background: </strong>The first edition of the World Health Organization (WHO) reporting system for soft tissue cytopathology (WHO system) has been released recently, providing a framework of 6 categories with their individual risk of malignancies. The 6th edition of the WHO tumours of soft tissue and bone is in the pipeline, including \"provisional\" tumour entities, reflecting developments in the identification of new entities, particularly based on high-throughput molecular techniques and immunohistochemical stains, including surrogates to the underlying molecular signatures, along with an evolution of tumour concepts.</p><p><strong>Summary: </strong>This review focuses on some of these recently identified and provisional soft tissue tumours; newly described immunohistochemical stains and concepts. The cytopathological features of various soft tissue tumours discussed in this include sarcomas with BCOR alterations, CIC rearranged sarcomas, pseudoendocrine sarcoma, MYOD1-positive spindle cell/sclerosing rhabdomyosarcoma, superficial CD34-positive pleomorphic fibroblastic tumour, pseudomyogenic haemangioendothelioma, chondroid synoviocytic neoplasm, and others.</p><p><strong>Key messages: </strong>This would contribute to the expanding and evolving cytopathological spectrum of soft tissue tumours, including sarcomas, including the value addition of certain more specific immunostains and molecular tests.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta CytologicaPub Date : 2026-09-05DOI: 10.1159/acy/abjag007
Jumpei Kashima, Magdalena M Brune, Nikolaus Deigendesch, Spasenija Savic Prince, Obinna Chijioke, Eva Darai-Ramqvist, Lukas Bubendorf
{"title":"Pulmonary Cytology in Transformation.","authors":"Jumpei Kashima, Magdalena M Brune, Nikolaus Deigendesch, Spasenija Savic Prince, Obinna Chijioke, Eva Darai-Ramqvist, Lukas Bubendorf","doi":"10.1159/acy/abjag007","DOIUrl":"10.1159/acy/abjag007","url":null,"abstract":"<p><strong>Background: </strong>Traditionally, pulmonary cytology has been used to diagnose and screen for a variety of respiratory diseases, including lung cancer. Owing to its rapid turnaround time compared with histological diagnosis, therapeutic decisions may occasionally need to be made based on cytological findings alone. In the era of precision medicine, however, biomarker assessment and molecular testing have become increasingly important, particularly in the management of lung cancer. In addition, the digitalization of pathological slides has facilitated the development of artificial intelligence (AI)-based diagnostic tools. The utility of these emerging technologies in pulmonary cytology is currently being actively investigated and continues to evolve, overcoming challenges including low input of tumor cells and the three-dimensional nature of cytological specimens.</p><p><strong>Summary: </strong>This review summarizes recent advances in pulmonary cytology, focusing on immunocytochemistry (ICC), proteomic analysis, and AI-assisted diagnostics. ICC provides crucial information not only for subclassification but also for the assessment of relevant therapeutic biomarkers. Proteomic analysis enables comprehensive characterization of thousands of protein expression profiles simultaneously, using limited cytology materials. But its future use in routine diagnostics must be established and tested in clinical trials. Furthermore, digitalized cytological slides can be utilized for AI-based analyses, potentially reducing diagnostic workload and providing additional predictive information. Despite these advances, challenges remain regarding specimen preparation, standardization, and validation.</p><p><strong>Key messages: </strong>The integration of morphology with appropriately validated molecular and computational methods has the potential to transform the framework of pulmonary cytology, extending its role from morphological diagnosis toward comprehensive and clinically significant characterization of pulmonary tumors.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148896302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Diagnostic Significance of Cell Clusters in Voided Urine in SurePath and ThinPrep Liquid-Based Cytology.","authors":"Yumiko Higuchi, Toshihiko Kato, Mei Oshima, Fuki Endo, Tomonari Toyama, Shiro Sugihara, Sotaro Kayano, Yasuo Imai","doi":"10.1159/acy/abjag005","DOIUrl":"10.1159/acy/abjag005","url":null,"abstract":"<p><strong>Introduction: </strong>Diagnostic significance of cell clusters (CCs) appearing in voided urine cytology remains unclear. Epithelial malignancy tends to form large clusters, but tumor cells get discohesive and clusters become smaller with disease progression. We investigated the diagnostic significance of CCs in the differentiation between low-grade urothelial carcinoma (LGUC) and high-grade urothelial carcinoma (HGUC) and then HGUC detection.</p><p><strong>Methods: </strong>In this study, voided urine samples, suspected of new-onset bladder cancer, with corresponding pathological diagnosis were analyzed. Malignancy other than urothelial carcinoma was excluded. Specimens prepared by the SurePath and ThinPrep liquid-based cytology methods were analyzed separately. Cytological diagnosis was based on The Paris System 2.0, and maximal CC size was measured. These data were subject to statistical analysis.</p><p><strong>Results: </strong>123 SurePath and 168 ThinPrep cases were analyzed in this study. Cytological diagnosis was significantly associated with pathological diagnosis in both SurePath and ThinPrep specimens. Then, CC was found to be present in approximately 60% of specimens prepared by both methods. There was no significant difference in CC size among benign lesions, LGUC, and HGUC in both SurePath and ThinPrep specimens. Meanwhile, high-risk cytology which consists of suspicious for HGUC and HGUC based on TPS 2.0 demonstrated similarly high specificity and positive-predictive value for HGUC detection irrespective of CC presence/absence, but sensitivity was significantly higher when CC was present in both SurePath and ThinPrep specimens.</p><p><strong>Conclusion: </strong>Size of CC was not useful for differentiating LGUC from HGUC, but CC presence was advantageous for detecting HGUC possibly due to a sufficient amount of collected cells for diagnosis.</p>","PeriodicalId":6959,"journal":{"name":"Acta Cytologica","volume":" ","pages":"1"},"PeriodicalIF":1.5,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148872454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}