Virchows Archiv最新文献

{"title":"Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP): what do we need to know?","authors":"Andrés Coca-Pelaz, Juan P Rodrigo, Abbas Agaimy, Dana M Hartl, Göran Stenman, Vincent Vander Poorten, Antti A Mäkitie, Mark Zafereo, Karthik N Rao, Gregory W Randolph, Alessandra Rinaldo, Alfio Ferlito","doi":"10.1007/s00428-024-03953-y","DOIUrl":"10.1007/s00428-024-03953-y","url":null,"abstract":"<p><p>Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) is a recently defined thyroid nodule category characterized by follicular architecture with papillary nuclear features but lacking classical papillary carcinoma features like papillae or psammoma bodies. The diagnosis of NIFTP is based on histological examination and excludes cases with high-risk mutations like BRAFV600E. NIFTP carries a low risk of recurrence and distant metastasis, prompting a more conservative surgical approach compared to classical papillary thyroid carcinoma. The management of NIFTP typically involves lobectomy with postoperative monitoring of thyroglobulin levels and performing neck ultrasounds. While the identification of NIFTP represents a significant advancement in thyroid cancer diagnosis, challenges remain in refining preoperative diagnostic tools and establishing optimal long-term follow-up strategies. The objective of this review is to provide a comprehensive overview of NIFTP, including its histopathological characteristics, molecular profile, clinical presentation, diagnostic criteria, management strategies, and future research directions.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"977-987"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142508935","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":"Multifocal vascular neoplasm with an EWSR1::NFATC2 gene fusion and progression to epithelioid angiosarcoma - a case report.","authors":"Jože Pižem, Emanuela Boštjančič, Andrej Zupan, Vladka Salapura, Blaž Mavčič, Ana Blatnik, Olga Blatnik, Mojca Unk, Izidor Kern, Miha Švarc, Alenka Matjašič","doi":"10.1007/s00428-024-03962-x","DOIUrl":"10.1007/s00428-024-03962-x","url":null,"abstract":"<p><p>There is an emerging group of distinct vascular neoplasms with NFATC1/2 fusions, involving bones and soft tissues and often displaying focal epithelioid morphology, variable atypia of endothelial cells, predominantly vasoformative and in some cases focal solid growth. Although they may show aggressive local growth and may recur locally, malignant behaviour has not been documented. We present a case of a 35-year-old woman with multiple vascular neoplasms with a EWSR1::NFATC2 fusion involving the lungs, multiple bones (vertebra, femurs, tibia, pelvis) and probably the liver. The bone lesions were locally aggressive and recurred after surgical treatment. Nine years after the first manifestation, there was progression to an epithelioid angiosarcoma. The patient died 3 months after the diagnosis of epithelioid angiosarcoma with massive lung and liver involvement(metastases). In addition to the EWSR1::NFATC2 fusion, an activating PIK3CA gene mutation was identified in the angiosarcoma but not in the previously diagnosed bone tumours. To the best of our knowledge, this is the first documentation of malignant progression of a vascular neoplasm with NFATC1/2 fusion as well as visceral (lung) involvement.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1175-1181"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142576798","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":"Utility of special AT-rich sequence-binding protein 2 (SATB2) immunohistochemistry as a marker for secondary perianal paget disease.","authors":"Krithika Shenoy, Kathleen Byrnes","doi":"10.1007/s00428-024-03906-5","DOIUrl":"10.1007/s00428-024-03906-5","url":null,"abstract":"<p><p>A panel-based approach using immunohistochemistry (IHC) is currently used for subtyping perianal Paget disease (PPD) in the absence of a synchronous neoplasm. Special AT-rich Sequence Binding Protein 2 (SATB2) has been established as a sensitive and specific marker for lower gastrointestinal tract carcinomas. We evaluated its performance as a marker of secondary PPD. A panel of IHCs including CK7, CK20, GCDFP-15, CDX2, and SATB2 were performed on fifteen cases of PPD (identified between 1991-2001) and seven cases of primary vulvar Paget disease with perianal involvement. Eight cases (53%) were classified as secondary PPD based on the presence of a synchronous (n = 7) or a metachronous neoplasm (n = 1). There was no differential staining for CK7 (positive in 7/7 primary vs. 7/8 secondary PPD; P = 1.00) and CK20 (positive in 4/7 primary vs. 8/8 secondary PPD; P = .08). GCDFP-15 was positive in 5/7 cases of primary PPD while negative in all cases of secondary PPD (P = .01). CDX2 was positive in all cases of secondary PPD (P = .001) while SATB2 was positive in 7/8 cases of secondary PPD (P = .01). Both CDX2 and SATB2 were positive in 1/7 cases of primary PPD. The addition of an IHC panel in conjunction with clinical/imaging findings can help definitively classify PPD as either primary or secondary in most cases. We show that SATB2 has comparable performance to CDX2 and can be a helpful additional tool.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1127-1132"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142056643","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":"The challenge of diagnosing neuroendocrine neoplasms: experience from a national reference center.","authors":"Xixi Zeng, Mengke Ma, Cong Tan, Shujuan Ni, Lei Wang, Meng Zhang, Weiqi Sheng, Shaolei Lu, Dan Huang","doi":"10.1007/s00428-024-03957-8","DOIUrl":"10.1007/s00428-024-03957-8","url":null,"abstract":"<p><p>Correctly diagnosing neuroendocrine neoplasm (NEN) has become increasingly challenging, given that more histomorphologic and immunophenotypic NEN mimics have been identified in recent years. A systemic review was conducted on the 4795 consult cases submitted with initial diagnoses of NEN to a national reference center in China from 2013 to 2021. Among them, 443 cases were misdiagnosed as epithelial NENs after reevaluation with the help of immunohistochemical and/or molecular tests, ranging from 7.1 to 13.2%, with yearly increases. The misdiagnoses varied among age groups and tumor sites. Exocrine carcinoma was the most common (63.2%), followed by mesenchymal tumors. Other common tumors that were misdiagnosed included hepatocellular carcinoma, salivary gland tumor, and gastrointestinal stromal tumor. Aberrant expression of neuroendocrine markers was frequent (218/408, 53.4%), with diffuse positivity ranging from 8.2 to 51.7% for synaptophysin, chromogranin A, and INSM1 stains in all non-NEN cases. Selecting appropriate immunohistochemical stains based on H&E morphology is the key to avoiding diagnostic pitfalls. Medical history and molecular genomic information greatly assist in correctly diagnosing NENs and their mimics.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1021-1031"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142547774","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":"Integrating single cell and bulk RNA sequencing data identifies RBM17 as a novel response biomarker for immunotherapy in bladder cancer.","authors":"Bo Song, Peishan Wu, Chong Wan, Qiangqiang Sun, Guangqi Kong","doi":"10.1007/s00428-024-03952-z","DOIUrl":"10.1007/s00428-024-03952-z","url":null,"abstract":"<p><p>Checkpoint inhibitors (CPIs) have been widely applied in the treatment of patients with bladder cancer (BLCA). However, there is still unmet need to dissect response predict biomarkers. To uncover CPI response-related marker genes in cancer cells, we utilized SCISSOR, integrating single-cell RNA and bulk RNA sequencing data. Transcriptomic and clinical data from IMvigor210, UNC-108, and BCAN/HCRN datasets were collected to evaluate and validate the identified biomarkers and signatures. Additionally, we analyzed TCGA-BLCA and local-BLCA RNA-seq data to investigate alternative splicing events (ASEs). Cell viability was assessed in T24 and UMUC3 cells with RBM17 upregulation or downregulation. Through SCISSOR analysis, we discovered that the expression levels of RBM17, TAP1, and PSMB8 were significantly associated with CPI response. Since PSMB8 displayed a highly positive correlation with TAP1, we developed a CPI response score (CRS) signature based on the expression profiles of RBM17 and TAP1. The CRS demonstrated robust predictive capacity in IMvigor210, UNC-108, and BCAN/HCRN datasets and was associated with higher tumor mutational burden (TMB), PD-L1 expression, and unique genomic features. Notably, RBM17 was not linked to the clinical outcomes of BLCA patients but positively correlated with BLCA cell proliferation in vitro. In the meantime, RBM17 was correlated with higher activity in core biological pathways, including antigen processing machinery, CD8 + T effector cells, cell cycle, DNA damage repair, epithelial-mesenchymal transition, histone regulation, and immune checkpoints. Moreover, the high-RBM17 group showed enrichment of LumU/Ba/sq subtypes but fewer FGFR3 alterations. Lastly, RBM17 significantly upregulated ASEs in BLCA samples, leading to higher neoantigen levels, a more inflamed tumor microenvironment, and improved CPI response. RBM17 is associated with higher ASEs and neoantigen levels, thereby potentiating the efficacy of CPI in BLCA. The established predictive signature, utilizing only two genes, has the potential to streamline clinical applications, providing a cost-effective alternative to expensive genomic, transcriptomic, and biological feature tests.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1133-1150"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142508933","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":"ETV6::NTRK3-associated papillary adenocarcinoma: let us play it by ear.","authors":"Diana Bell, Ellie Maghami, Rania Bakkar, Michelle Afkhami","doi":"10.1007/s00428-024-03735-6","DOIUrl":"10.1007/s00428-024-03735-6","url":null,"abstract":"<p><p>Ceruminous glands are modified apocrine glands, situated in the external auditory canal (EAC) that, together with sebaceous glands, produce cerumen. The neoplastic transformation of these structures is exceedingly rare. We encounter two cases of EAC adenocarcinoma with ETV6::NTRK3 fusion. Despite this genetic overlap, the morphology and immunophenotype delineate its clear separation from secretory carcinoma. These cases demonstrate novel primary EAC adenocarcinoma with papillary morphology, which expands the ever-increasing list of ETV6::NTRK3-positive malignancies and which we would like to term ETV6::NTRK3-translocation associated papillary adenocarcinoma. We also advocate the use of molecular techniques in rare tumors of uncertain type or differentiation, to increase understanding and possibilities of reproducible classification of these rare neoplasms. Pathologists and oncologists should recognize this entity, which leads to a direct approach for detecting NTRK fusion for appropriate treatment.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1161-1165"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139418192","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":"Reporting of somatic variants in clinical cancer care: recommendations of the Swiss Society of Molecular Pathology.","authors":"Yann Christinat, Baptiste Hamelin, Ilaria Alborelli, Paolo Angelino, Valérie Barbié, Bettina Bisig, Heather Dawson, Milo Frattini, Tobias Grob, Wolfram Jochum, Ronny Nienhold, Thomas McKee, Matthias Matter, Edoardo Missiaglia, Francesca Molinari, Sacha Rothschild, Anna Bettina Sobottka-Brillout, Erik Vassella, Martin Zoche, Kirsten D Mertz","doi":"10.1007/s00428-024-03951-0","DOIUrl":"10.1007/s00428-024-03951-0","url":null,"abstract":"<p><p>Somatic variant testing through next-generation sequencing (NGS) is well integrated into Swiss molecular pathology laboratories and has become a standard diagnostic method for numerous indications in cancer patient care. Currently, there is a wide variation in reporting practices within our country, and as patients move between different hospitals, it is increasingly necessary to standardize NGS reports to ease their reinterpretation. Additionally, as many different stakeholders-oncologists, hematologists, geneticists, pathologists, and patients-have access to the NGS report, it needs to contain comprehensive and detailed information in order to answer the questions of experts and avoid misinterpretation by non-experts. In 2017, the Swiss Institute of Bioinformatics conducted a survey to assess the differences in NGS reporting practices across ten pathology institutes in Switzerland. The survey examined 68 reporting items and identified 48 discrepancies. Based on these findings, the Swiss Society of Molecular Pathology initiated a Delphi method to reach a consensus on a set of recommendations for NGS reporting. Reports should include clinical information about the patient and the diagnosis, technical details about the sample and the test performed, and a list of all clinically relevant variants and variants of uncertain significance. In the absence of a consensus on an actionability scheme, the five-class pathogenicity scheme proposed by the ACMG/AMP guideline must be included in the reports. The Swiss Society of Molecular Pathology recognizes the importance of including clinical actionability in the report and calls on the European community of molecular pathologists and oncologists to reach a consensus on this issue.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1033-1039"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11666653/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142508936","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":"EWSR1::ATF1 fusions characterize a group of extra-abdominal epithelioid and round cell mesenchymal neoplasms, phenotypically overlapping with sclerosing epithelioid fibrosarcomas, and intra-abdominal FET::CREB fusion neoplasms.","authors":"Bharat Rekhi, Josephine K Dermawan, Karen J Fritchie, Annette Zimpfer, Tareq M Mohammad, Fatima S Ali, Koushik Nandy, Youran Zou, Robert Stoehr, Abbas Agaimy","doi":"10.1007/s00428-024-03879-5","DOIUrl":"10.1007/s00428-024-03879-5","url":null,"abstract":"<p><p>With the increasing use of next generation sequencing in soft tissue pathology, particularly in neoplasms not fitting any World Health Organization (WHO) category, the spectrum of EWSR1 fusion-associated soft tissue neoplasms has been expanding significantly. Although recurrent EWSR1::ATF1 fusions were initially limited to a triad of mesenchymal neoplasms including clear cell sarcoma of soft tissue, angiomatoid fibrous histiocytoma and malignant gastrointestinal neuroectodermal tumor (MGNET), this family has been expanding. We herein describe 4 unclassified extra-abdominal soft tissue (n = 3) and bone (n = 1) neoplasms displaying epithelioid and round cell morphology and carrying an EWSR1::ATF1 fusion. Affected were 3 males and 1 female aged 20-56 years. All primary tumors were extra-abdominal and deep-seated (chest wall, mediastinum, deltoid, and parapharyngeal soft tissue). Their size ranged 4.4-7.5 cm (median, 6.2). One patient presented with constitutional symptoms. Surgery with (2) or without (1) neo/adjuvant therapy was the treatment. At last follow-up (8-21 months), 2 patients developed progressive disease (1 recurrence; 1 distant metastasis). The immunophenotype of these tumors is potentially misleading with variable expression of EMA (2 of 3), pankeratin (2 of 4), synaptophysin (2 of 3), MUC4 (1 of 3), and ALK (1 of 3). All tumors were negative for S100 and SOX10. These observations point to the existence of heretofore under-recognized group of epithelioid and round cell neoplasms of soft tissue and bone, driven by EWSR1::ATF1 fusions, but distinct from established EWSR1::ATF1-associated soft tissue entities. Their overall morphology and immunophenotype recapitulate that of the emerging EWSR1/FUS::CREB fusion associated intra-abdominal epithelioid/round cell neoplasms. Our cases point to a potentially aggressive clinical behavior. Recognizing this tumor type is mandatory to delineate any inherent biological and/or therapeutic distinctness from other, better-known sarcomas in the differential diagnosis including sclerosing epithelioid fibrosarcoma.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"995-1005"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11666693/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141731438","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":"Morphological and immunohistochemical evaluation in distinguishing post-radiotherapy serous-like endometrial change (PoRSEC) and serous endometrial intraepithelial carcinoma (SEIC).","authors":"Damiano Arciuolo, Giulia Scaglione, Antonio Travaglino, Nicoletta D'Alessandris, Angela Santoro, Frediano Inzani, Belen Padial Urtueta, Stefania Sfregola, Antonio Raffone, Caterina Fulgione, Michele Valente, Roberta Benvenuto, Federica Cianfrini, Gian Franco Zannoni","doi":"10.1007/s00428-024-03818-4","DOIUrl":"10.1007/s00428-024-03818-4","url":null,"abstract":"<p><p>Uteri from women undergoing chemoradiotherapy (CRT) may show reactive atypia which may mimic serous endometrial intraepithelial carcinoma (SEIC). We aimed to assess the prevalence and morphological/immunohistochemical features of post-radiotherapy serous-like endometrial changes (PoRSEC) in women undergone CRT for locally advanced cervical cancer, with a focus on the differential diagnosis with SEIC. Consecutive patients with locally advanced cervical cancer undergone CRT between 2011 and 2018 were reviewed. Endometrial histological specimens were assessed for the presence of PoRSEC. Twenty-two cases of SEIC were included for comparison. Immunohistochemistry for p53, p16, and Ki67 was performed. Out of 244 reviewed patients, 36 (14.7%) showed PoRSEC. The degree of nuclear atypia was similar between PoRSECs and SEIC. However, a papillary architecture with areas of confluent papillae was only observed in SEIC. SEIC cases showed a high mitotic activity as opposed to PoRSEC cases. The expression of p53 was aberrant in all SEICs but in none of the PoRSECs; however, 13/36 PoRSECs showed p53 positivity in most tumor cells, potentially mimicking a mutation pattern. A block-type p16 expression was observed in all SEICs and in 16/36 PoRSECs. Mean Ki67 expression was 26.9% in SEIC (range 5-70%) and 8.16% in PoRSEC (range 5-35%). While SEIC showed sharp morphological and immunohistochemical demarcation, PoRSEC were more heterogenous and merged imperceptibly with normal endometrium. In conclusion, PoRSEC may mimic SEIC both morphologically and immunohistochemically. However, a papillary architecture with cytological demarcation is typically observed in SEIC but not in PoRSEC.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"989-994"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11666609/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141793627","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":"A potential conundrum in dermatopathology: molecularly confirmed superficial ossifying fibromyxoid tumors with unusual histomorphologic findings and a novel fusion.","authors":"Antonia Syrnioti, Kyriakos Chatzopoulos, Darcy A Kerr, Dianne E Torrence, Meera Hameed, Narasimhan P Agaram, Cristina Antonescu, Konstantinos Linos","doi":"10.1007/s00428-024-03895-5","DOIUrl":"10.1007/s00428-024-03895-5","url":null,"abstract":"<p><p>Ossifying fibromyxoid tumor (OFMT) is a rare soft tissue neoplasm of uncertain histogenesis, primarily arising in subcutaneous tissues of the extremities, head and neck, or trunk. Most cases present as well-circumscribed masses with a characteristic morphologic appearance, comprising cytologically bland ovoid cells with fibromyxoid stroma, a peripheral rim of metaplastic bone, and lobulated architecture. Nevertheless, tumors displaying unusual morphologic characteristics pose significant diagnostic challenges, requiring the detection of a pathogenic fusion for a definitive diagnosis. The majority of OFMTs exhibits PHF1 gene rearrangements. Herein, we present six cases of molecularly confirmed OFMTs with uncommon histomorphologic features, including the absence of myxoid stroma, extensive chondroid differentiation, prominent clear cell morphology, collagen entrapment, interdigitating fibrocollagenous and fibromyxoid stromal elements, and conspicuous red blood cell extravasation. One case harbored a novel fusion (EPC1::SUZ12). This study emphasizes the broad range of morphologic manifestations that can be encountered in OFMT and the crucial role of molecular testing in establishing a conclusive diagnosis in such cases.</p>","PeriodicalId":23514,"journal":{"name":"Virchows Archiv","volume":" ","pages":"1063-1073"},"PeriodicalIF":3.4,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142376104","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}