Cancer Cytopathology最新文献

{"title":"Correction to \"The fascinating history of papillary thyroid carcinoma nuclei: revelation of two nuclear morphologies-\"Classical papillary\" and \"papillary-like\", with different pathobiologic characteristics\".","authors":"","doi":"10.1002/cncy.70115","DOIUrl":"10.1002/cncy.70115","url":null,"abstract":"","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70115"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13484187/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147940181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to \"Evaluating the role of metaplasia in the cytologic diagnosis of pleomorphic adenoma: A multi-institutional study of 253 cases\".","authors":"","doi":"10.1002/cncy.70119","DOIUrl":"10.1002/cncy.70119","url":null,"abstract":"","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70119"},"PeriodicalIF":3.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148013642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Practical exploration of real-time visual interactive artificial intelligence technology in cytopathology education.","authors":"Wenhao Ren, Lulu Rong, Qian Wang, Jie Wang, Chunhua Cheng, Yanli Zhu, Jun Lu","doi":"10.1002/cncy.70097","DOIUrl":"10.1002/cncy.70097","url":null,"abstract":"<p><strong>Background: </strong>Proficiency in cytopathologic diagnosis depends heavily on extensive hands-on practice and immediate error correction. Traditional teaching models, however, are constrained by limited practice opportunities and delayed feedback, which fails to meet the core skill-development needs of residents.</p><p><strong>Methods: </strong>In total, 45 pathology residents were enrolled and assigned to two groups. The experimental group (n = 20) adopted a tripartite teacher-artificial intelligence-resident collaborative teaching model, whereas the control group (n = 25) received conventional instruction. Both groups underwent an identical 8-week teaching cycle.</p><p><strong>Results: </strong>The questionnaire results from the experimental group indicated that 19 of 20 residents (9%) deemed the new model highly necessary, and 15 of 20 (75%) believed it significantly improved their diagnostic competence. Semistructured interviews further revealed that the model enhanced diagnostic ability, facilitated personalized learning, and alleviated learning anxiety. For objective metrics, the experimental group demonstrated a significantly higher postintervention concordance rate for gray-zone cell identification (78.65%) compared with both their preintervention baseline (64.38%) and the contemporaneous control group (66.84%; t = 8.962; p < .001). In addition, the experimental group exhibited a markedly faster diagnostic speed (mean ± standard deviation, 3.05 ± 0.52 minutes per case) compared with their preintervention performance (5.92 ± 0.85 minutes per case) and the control group (5.63 ± 0.79 minutes per case; t = 14.821; p < .001). No statistically significant changes were observed in the control group (p > .05).</p><p><strong>Conclusions: </strong>This study demonstrates that artificial intelligence technology integrated with real-time visual interaction effectively improves the cytopathologic diagnostic skills of residents and merits wider promotion in pathology education.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70097"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147962212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk of malignancy for biliary cytology based on World Health Organization (WHO) reporting system for pancreaticobiliary cytopathology.","authors":"Annie Elizabeth Abraham, Xinjun Wang, Imani Hargett, Zaynab Pharaa, Camille Sears, Mithat Gonen, Rajmohan Murali, Oscar Lin, Alice Wei, Adrian Gonzalez-Aguirre, Pari Shah, Carlie Sigel","doi":"10.1002/cncy.70109","DOIUrl":"10.1002/cncy.70109","url":null,"abstract":"<p><strong>Background: </strong>The World Health Organization (WHO) classification for pancreaticobiliary cytopathology stratifies risk of malignancy (ROM) and outcome for pancreatic fine-needle aspirations (FNAs). ROM for biliary cytology, particularly for WHO categories Pan-low (IV) and Pan-high (V), has not been well examined.</p><p><strong>Methods: </strong>Retrospective data of biliary cytology diagnosed from 2016 to 2019 were collected. WHO classification was assigned. Malignant outcome was determined by histologic correlation or clinical progression/death. Excluding clinical follow-up <3 months (if no histology), the ROM, odds ratio, performance characteristics, and overall survival were calculated.</p><p><strong>Results: </strong>A total of 1056 biliary cytology cases (from 789 patients) were included. Sample types were: 757 (72%) biliary brush/wash, 115 (11%) FNA, and 184 (17%) other. Same-site histologic correlation was 292 (28%) and histology of metastasis in 124 (12%). The median follow-up (for benign) was 1431 days. Malignant outcome occurred in 704 (n = 789, 89%) of patients. Absolute ROM (%) for WHO I to VII by biliary brush/wash and FNA were: 92, 72, 87, 0, 100, 94, 100, and 50, 46, 73, N/A, 100, 80, 100, respectively. A high-tier (V-VII) category had significantly higher odds of malignancy regardless of biopsy modality, presence of stent, or autoimmune cholangitis.</p><p><strong>Conclusion: </strong>Absolute ROM for biliary lesions is high for WHO I through III and is at least partly because of difficulty in sampling cancers, particularly those extrinsically obstructing the bile duct. The rarity of low-grade biliary lesions impedes AROM assessment for Pan-low (WHO IV). The clinical value of biliary Pan-high (WHO V) remains uncertain because of rarity of high-grade noninvasive lesions and difficulty in cytology diagnosis.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70109"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147959583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lung adenocarcinoma with malignant serous effusions: A comprehensive clinicopathologic, molecular, and outcome analysis.","authors":"Weijie Ma, Jiannan Li, A Aziz Ould Ismail, Tianhong Li, Darcy A Kerr, Laura J Tafe, Xiaoying Liu","doi":"10.1002/cncy.70108","DOIUrl":"10.1002/cncy.70108","url":null,"abstract":"<p><strong>Background: </strong>Malignant serous effusions (MSEs), including pleural, pericardial, and peritoneal effusions, are common in advanced lung adenocarcinoma (LUAD). However, integrated clinicopathologic, molecular, treatment, and outcome data across effusion sites remain incompletely defined.</p><p><strong>Methods: </strong>This study retrospectively analyzed 120 cytology-confirmed LUAD-associated MSE cases from a single academic center by integrating gross fluid features, cytopathology, immunohistochemistry, targeted next-generation sequencing (NGS), systemic therapy, and clinical outcomes, including survival from first malignant effusion (SME) and overall survival (OS).</p><p><strong>Results: </strong>Effusions were pleural (85 of 120; 70.8%), pericardial (28 of 120; 23.3%), and peritoneal (7 of 120; 5.8%). Median SME was 3.8 months, and was shortest in the small peritoneal effusion subgroup (1.0 months). OS differed by site, with pericardial involvement showing the shortest OS (6.1 months). Thyroid transcription factor 1 (TTF-1) was positive in 72.5% of cases. Programmed death ligand 1 (PD-L1) testing (n = 85) showed a tumor proportion score (TPS) of ≥1% in 80% of cases and TPS of ≥50% in 36.5% of cases. Molecular profiling was completed in 111 of 120 cases (92.5%) by identifying TP53 mutations in 47 of 111 (42.3%) and actionable driver alterations in 42.3% of cases, most commonly involving EGFR, KRAS, BRAF, ALK, and ROS1. TTF-1 positivity was associated with higher rates of actionable driver alterations and higher PD-L1 expression. PD-L1 negativity, TTF-1 negativity, and an absence of actionable driver alterations were associated with shorter SME and OS. Dual TTF-1/PD-L1 negativity defined the poorest risk subgroup (median SME, 1.2 months; median OS, 1.4 months). Multivariable analysis confirmed that TTF-1 negativity and a lack of actionable drivers remained independently adverse. Among treated patients, immunotherapy-based regimens were associated with the longest SME (6.7 months), whereas tyrosine kinase inhibitor-based therapy was associated with the longest OS (26.0 months).</p><p><strong>Conclusions: </strong>Integration of cytology, immunophenotype, genomics, and treatment delineates distinct prognostic subsets in LUAD with MSE. The absence of actionable driver alterations and TTF-1 negativity remains an independent adverse prognostic factor, with dual TTF-1/PD-L1-negative MSE showing particularly poor SME and OS.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70108"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147962232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of lymphocyte-predominant breast cancer using microRNA expression in cytology specimens.","authors":"Azusa Kai, Koji Arihiro, Hideo Shigematsu, Yukari Ohue-Uchihata, Momoko Nakamura, Ai Amioka, Shinsuke Sasada, Morihito Okada","doi":"10.1002/cncy.70114","DOIUrl":"10.1002/cncy.70114","url":null,"abstract":"<p><strong>Background: </strong>Tumor-infiltrating lymphocytes are prognostic and predictive biomarkers of breast cancer; however, conventional assessment is hindered by invasiveness and subjective evaluation, limiting clinical reproducibility. This study investigated the utility of microRNA (miRNA) profiles in predicting lymphocyte-predominant breast cancer (LPBC).</p><p><strong>Methods: </strong>This study included 56 patients with breast cancer who underwent fine-needle aspiration cytology at the time of diagnosis (28 LPBC and 28 non-LPBC cases). Total RNA was extracted from cytology smear specimens, and the expression levels of six candidate miRNAs (miR-30a-3p, miR-187, miR-196b, miR-1247, miR-4485, and miR-6510) were quantified using reverse-transcriptase polymerase chain reaction. The performance in identifying LPBC was evaluated using receiver operating characteristic curve analysis and logistic regression models.</p><p><strong>Results: </strong>All six miRNAs showed significantly lower expression levels in the LPBC group than in the non-LPBC group (all p < .05). Receiver operating characteristic curve analysis demonstrated moderate to high diagnostic accuracy, with an area under the curve of 0.708 for miR-30a-3p, 0.739 for miR-187, 0.783 for miR-196b, 0.777 for miR-1247, 0.790 for miR-4485, and 0.673 for miR-6510. Multivariate analysis further identified each miRNA as an independent diagnostic predictor for LPBC.</p><p><strong>Conclusions: </strong>miRNA profiling of cytologic samples enabled the objective identification of LPBC. These findings suggest that specific miRNA expression patterns reflect the tumor immune microenvironment and can be used to evaluate the status of tumor-infiltrating lymphocytes in breast cancer.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70114"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13177170/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147940164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial intelligence–assisted urine cytology based on the Paris System for Reporting Urothelial Carcinoma","authors":"Lan Chen MD, PhD,&nbsp;Xinyi Cao BS,&nbsp;Zongyue Lu BS,&nbsp;Longteng Liu MSc,&nbsp;Mingjun Sun BS,&nbsp;Yulong Wu BS,&nbsp;Wei Zhang PhD","doi":"10.1002/cncy.70120","DOIUrl":"10.1002/cncy.70120","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Urine cytology is a noninvasive and valuable tool for detecting urothelial carcinoma but suffers from variable sensitivity and observer dependency. Artificial intelligence (AI) may enhance the diagnostic accuracy and efficiency of urine cytology. The objective of this study was to develop and validate an AI-based cytology system for urothelial carcinoma detection in both clinical and screening contexts.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>In total, 328 retrospective clinical cases and 1489 prospective health screening samples were analyzed. All specimens underwent liquid-based cytology and were digitized at ×20 magnification. For model development, ed 269 annotated training slides (56,710 cells) were used. The AI pipeline mimicked cytopathologist workflow, integrating deep learning–based cell detection and segmentation with feature extraction and support vector machine classification into AI-negative, AI-atypical, and AI-positive categories according to The Paris System for Reporting the Urinary Cytology. Agreement was assessed using weighted κ values and prevalence-adjusted, bias-adjusted κ values.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In the clinical cohort, AI achieved 83.0% agreement with histopathology and 82.6% agreement with expert cytology. Weighted κ values (κ, 0.631–0.661) reflected substantial agreement, with discrepancies mainly between adjacent categories. In the health screening cohort, the prevalence-adjusted, bias-adjusted κ was 0.647 despite low prevalence. AI demonstrated a high negative predictive value of 99.7% and negative percent agreement of 82.3%, with a minimal false-omission rate (0.25%).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>AI-assisted urine cytology exhibited substantial concordance with expert interpretation and histopathologic standards. Its capability of screen-out and high negative predictive value support its potential as a reliable triage tool, improving workflow efficiency while maintaining diagnostic reliability in large-scale screening.</p>\u0000 </section>\u0000 </div>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148136398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scrape versus imprint cytology in sentinel lymph nodes of breast cancer patients after neoadjuvant therapy: Does combination add value?","authors":"Egemen Akıncıoğlu, Elçin Kadan, Hale Kıvrak, Aysu Sadioğlu, İlke Evrim Seçinti, Gülçin Şimşek","doi":"10.1002/cncy.70106","DOIUrl":"10.1002/cncy.70106","url":null,"abstract":"<p><strong>Background: </strong>The primary objective of this study is to evaluate the feasibility of cytological methods in intraoperative consultation for patients receiving neoadjuvant therapy (NT), to compare the sensitivity, specificity, and accuracy of imprint, scrape, and combined cytology, and to assess the reliability of these methods in lymph nodes (LNs) affected by treatment-related changes. Additionally, this study aims to investigate the impact of metastatic tumor size on the diagnostic accuracy of cytological methods.</p><p><strong>Methods: </strong>Ninety-two patients who underwent sentinel LN sampling during breast surgery between June 2023 and December 2024 were included in this retrospective study. Diagnostic performance of imprint, scrape, and combined cytology was evaluated according to NT status, metastatic tumor size, and treatment-related changes. Overall accuracy was assessed using Receiver operating characteristic (ROC) analysis, with pairwise comparisons performed using DeLong's test.</p><p><strong>Results: </strong>A total of 300 LNs were evaluated, of which 161 (53.6%) were from patients receiving NT. In this subgroup, imprint cytology showed high specificity but limited sensitivity, whereas scrape and combined cytology demonstrated higher sensitivity and overall diagnostic accuracy. ROC analysis showed significantly higher diagnostic performance for scrape and combined cytology compared with imprint cytology in patients receiving NT (p = .005). Across all subgroup analyses, including metastasis size and therapy-related changes, combined cytology consistently showed the highest sensitivity, whereas imprint cytology maintained the highest specificity.</p><p><strong>Conclusion: </strong>Scrape cytology showed significantly higher diagnostic performance than imprint cytology, particularly after NT. Combined cytology improved performance compared with imprint cytology but did not significantly outperform scrape cytology.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70106"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13181531/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147962305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing urothelial carcinoma diagnosis with artificial intelligence-integrated urine cytology: Biopsy-validated accuracy and efficiency gain.","authors":"Sigfred Lajara, Jacqueline Cuda, Daniel L Geisler, Caroline Staniszewski, Wei-Lei Yang, Karen Atkison, Chih-Yun Lin, Guowei Shao, Tien-Jen Liu, Barbara Crothers, Rajiv Dhir, Samer N Khader","doi":"10.1002/cncy.70110","DOIUrl":"10.1002/cncy.70110","url":null,"abstract":"<p><strong>Background: </strong>Urine cytology is a noninvasive tool for detecting urothelial carcinoma, yet its performance depends heavily on expert cytologists and time-intensive glass slide review. Artificial intelligence (AI)-assisted digital cytology has emerged as a potential solution to improve diagnostic sensitivity and workflow efficiency. This retrospective study aimed to evaluate the diagnostic performance and workflow impact of AIxURO, an AI-assisted digital urine cytology system, in a high-volume US medical center.</p><p><strong>Methods: </strong>Two hundred ThinPrep cytology slides were digitized with two distinct customized scanners integrated into the AIxURO imaging system (AIS-1 and AIS-2). Three reviewers independently assessed each case across three diagnostic modalities: microscopy, AIxURO-AIS-1, and AIxURO-AIS-2. Performance for binary bladder cancer detection was compared against expert consensus cytology diagnoses; review time, biopsy correlation, and performance in patients presenting with hematuria were also evaluated.</p><p><strong>Results: </strong>AIxURO (AIS-1 and AIS-2) improved diagnostic sensitivity (85.0% and 88.3%) and negative predictive value (NPV) (85.1% and 87.6%) relative to microscopy (79.3% and 82.0%), whereas accuracy remained comparable across modalities. These sensitivity gains were accompanied by lower specificity (85.7% and 82.3% vs. 94.3%) and positive predictive value (PPV) (85.6% and 83.3% vs. 93.3%) compared with microscopy. Both AI modalities reduced classifying atypical urothelial cells and above cases as negative for high-grade urothelial carcinoma cases, and shortened median review time by 66%-78% (p < .0001). Among the 200 cases, 98 (49%) had biopsy confirmation, in which AIxURO showed higher sensitivity and NPV than microscopy. In 16 hematuria cases with biopsy correlation, AI-assisted screening achieved superior diagnostic performance.</p><p><strong>Conclusions: </strong>AIxURO enhances sensitivity for detecting urothelial carcinoma and markedly improves screening efficiency, with a tradeoff of reduced specificity/PPV compared with microscopy.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70110"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13181225/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147962180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the role of metaplasia in the cytologic diagnosis of pleomorphic adenoma: A multi-institutional study of 253 cases.","authors":"Vanda F Torous, Amin Heidarian, Zubair W Baloch, Zahra Maleki, Kathleen Montone, Esther D Rossi, William C Faquin","doi":"10.1002/cncy.70107","DOIUrl":"10.1002/cncy.70107","url":null,"abstract":"<p><strong>Background: </strong>Pleomorphic adenoma (PA) is the most common benign salivary gland neoplasm detected by fine-needle aspiration (FNA). However, metaplastic changes within PA can complicate its cytologic interpretation. This study evaluates the impact of metaplasia on the FNA interpretation in a large, multi-institutional cohort.</p><p><strong>Methods: </strong>A two-armed study design was employed: one included 200 consecutive PA resections and the corresponding FNAs, and the second included 53 PA cases with known metaplastic features identified by cytologic or pathologic review.</p><p><strong>Results: </strong>Histologic assessment revealed metaplasia in 16% of the 200 PA cases. Although the majority (83%) were cytologically classified as Neoplasm: Benign, indeterminate diagnoses were more common in cases with metaplasia (25%) than in those without (15.5%). Squamous metaplasia was frequently interpreted as indeterminate relative to other types of metaplasia, and a statistical trend was observed between the extent of metaplasia and indeterminate categorization. In the multicenter arm, FNA cases with metaplasia were more frequently interpreted as indeterminate compared to FNA cases without metaplasia (61.8% vs. 15.8%, p < .01).</p><p><strong>Conclusions: </strong>Metaplastic change in PA can pose diagnostic challenges. Although most FNA cases with limited metaplastic features are appropriately classified, extensive metaplasia is more likely to result in an indeterminate interpretation.</p>","PeriodicalId":9410,"journal":{"name":"Cancer Cytopathology","volume":"134 6","pages":"e70107"},"PeriodicalIF":2.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147926564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}