International Journal of Surgical Pathology最新文献

{"title":"A SMARCA4-Deficient Uterine Sarcoma Arising in a Uterine Adenosarcoma: Expanding the Spectrum of SMARCA4-Deficient Uterine Neoplasms With Hybrid Morphologic Features.","authors":"Fiorella Rosas-Chavez, Brenda Baltodano, Fang Fan, Sue Chang, Andrea A Sánchez-Sánchez, Javier A Arias-Stella","doi":"10.1177/10668969261483647","DOIUrl":"https://doi.org/10.1177/10668969261483647","url":null,"abstract":"<p><p>Background<i>SMARCA4</i> genetic alterations have been associated with aggressive neoplasms in various organs. In the uterus, SMARCA4-deficiency has been reported rarely, typically presenting as undifferentiated uterine sarcoma with a poor prognosis and younger age onset. The spectrum of SMARCA4-driven uterine tumors has recently expanded reporting hybrid features to include adenosarcoma components.Clinical PresentationWe report a 27-year-old woman who presented with abnormal uterine bleeding. The endometrial curettage revealed a high-grade adenosarcoma. One month later, the patient underwent tumor debulking surgery. The histologic examination showed a tumor with leaf-like architecture and marked stromal atypia. The stromal component exhibited epithelioid and rhabdoid features, with cells arranged in nests. Extensive lymphovascular invasion and infiltration of surrounding tissues were noted. <i>SMARCA4</i> mutation was confirmed by next-generation sequencing, with no other mutations detected. Despite prompt initiation of aggressive chemotherapy, the cancer continued to spread to the lungs and peritoneum. The patient died 19 months after the initial presentation.ConclusionThis case report reinforces the emerging pattern of SMARCA4-deficient tumors presenting aggressively in premenopausal women with hybrid morphologic features. It highlights the importance of molecular testing in patients of all ages and the need for early recognition and prompt treatment of tumors harboring mutations associated with rapid progression.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261483647"},"PeriodicalIF":0.9,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149166010","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":"Superficial Pleomorphic Mesenchymal Tumors.","authors":"Carlos Monteagudo","doi":"10.1177/10668969261483648","DOIUrl":"https://doi.org/10.1177/10668969261483648","url":null,"abstract":"<p><p>The broad category of \"superficial pleomorphic mesenchymal tumors\" encompasses many tumor types. The prototypical ones are atypical fibroxanthoma and pleomorphic dermal sarcoma. Other tumor types are atypical fibrous histiocytoma, spindle cell/pleomorphic lipoma, atypical spindle cell and pleomorphic lipomatous tumor, superficial pleomorphic liposarcoma, pleomorphic fibroma, superficial CD34 fibroblastic tumor, myxoinflammatory fibroblastic sarcoma, and superficial myxofibrosarcoma. Since most superficial pleomorphic tumors lack specific immunohistochemical and/or genetic markers, a differential diagnosis is paramount and includes both mesenchymal and non-mesenchymal tumors. This manuscript summarizes essential clinicopathological, immunohistochemical, genetic, and, when applicable, epigenetic clues for an accurate diagnosis, with a particular focus on differential diagnosis.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261483648"},"PeriodicalIF":0.9,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149165532","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":"Unveiling the Rarity: Melanotic Neuroectodermal Tumor of Infancy in the Forearm-A Diagnostic Challenge.","authors":"Aradhana Singh Hada, Poonam Panjwani, Bharat Rekhi, Mukta Ramadwar, Amit Janu, Prakash Nayak, Maya Prasad","doi":"10.1177/10668969261483657","DOIUrl":"https://doi.org/10.1177/10668969261483657","url":null,"abstract":"<p><p>Melanotic neuroectodermal tumor of infancy (MNTI) is a rare neural crest-derived neoplasm typically arising in the craniofacial region. Extracranial involvement, particularly in long bones, is exceedingly uncommon and may pose a diagnostic challenge. We report a 4.5-month-old male infant presenting with a rapidly enlarging forearm mass involving the radius with soft tissue extension. The initial biopsy suggested a malignant round cell tumor of neuroectodermal differentiation. A diagnosis of Ewing sarcoma was considered, based on clinicoradiological impression. The tumor showed poor response to chemotherapy, necessitating an above-elbow amputation. Histopathological examination of the resected specimen revealed a characteristic biphasic tumor composed of small neuroblastic cells and pigmented epithelial cells. Immunohistochemical staining confirmed the diagnosis of a MNTI. This extremely rare report highlights the diagnostic pitfalls on limited biopsy and underscores the importance of recognizing biphasic morphology with appropriate immunohistochemical correlation.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261483657"},"PeriodicalIF":0.9,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149166891","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":"Lung Localization of Endosalpingiosis: Challenges of Rare Manifestation of Müllerianosis.","authors":"Mattia Dominoni, Gabriele Rasore, Manuela Torraca, Martina Rita Pano, Stefania Cesari, Gioacchino D'Ambrosio, Barbara Gardella","doi":"10.1177/10668969261484981","DOIUrl":"https://doi.org/10.1177/10668969261484981","url":null,"abstract":"<p><p>Endosalpingiosis (ES) is a benign, nonneoplastic condition of the Müllerian system characterized by the ectopic implantation of fallopian tube-like ciliated columnar epithelium. Unlike endometriosis, ES lacks endometrial stroma and therefore does not produce the characteristic hemorrhagic episodes or extensive inflammatory responses associated with endometriosis. Although ES is primarily identified in the visceral pelvic peritoneum, extrapelvic manifestations are exceedingly rare, with pulmonary and pleural localization, accounting for ∼0.1% of reports. This report describes the clinical presentation of thoracic ES in a 40-year-old woman who presented with catamenial spontaneous primary pneumothorax. Despite a remote surgical history for ovarian endometriosis 10 years earlier, the patient had a prolonged period of clinical latency and no evidence of current pelvic recurrence. Videothoracoscopic surgery revealed a 5-mm apical pulmonary nodule and diffusely calcified pleural plaques. Histopathology and immunohistochemistry are remain gold-standard diagnostic methods for differentiating ES from thoracic endometriosis syndrome or malignancy. The diagnosis was confirmed by epithelial immunoreactivity for Müllerian transcription factors (PAX8 and WT1), keratin 7, and estrogen/progesterone receptors, together with the absence of cluster of differentiation 10 expression, which argued against endometrial stroma, and calretinin negativity, which argued against mesothelial origin. The pathophysiology of thoracic ES may resemble that of pulmonary endometriosis, involving transdiaphragmatic or vascular migration of Müllerian cells. For symptomatic presentations, surgical excision combined with long-term suppressive hormonal therapy is recommended to reduce epithelial proliferation. Given that the emerging literature suggests a possible link between ES and gynecological malignancies, rigorous long-term postoperative surveillance remains essential.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261484981"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136625","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":"Hydrophilic Polymer Emboli-A Rare Finding Following Intravascular Procedures.","authors":"Laura Cuello, Omar Tanweer, Hsiang-Chih Lu","doi":"10.1177/10668969261483655","DOIUrl":"https://doi.org/10.1177/10668969261483655","url":null,"abstract":"","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261483655"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136467","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":"Locally Aggressive Breast Desmoid Fibromatosis in a Young Woman With Multiple Fibroadenomas.","authors":"Marilin Rosa","doi":"10.1177/10668969261482140","DOIUrl":"https://doi.org/10.1177/10668969261482140","url":null,"abstract":"<p><p>Desmoid fibromatosis is a rare spindle cell neoplasm with fibroblastic/myofibroblastic differentiation, accounting for less than 0.2% of all breast tumors. It affects predominantly women and although can be locally aggressive, it has no metastatic potential. Diagnosis requires tissue sampling, correlation with imaging and clinical findings, and the use of ancillary studies. Breast fibromatosis typically exhibits nuclear β-catenin positivity, with variable expression of smooth muscle actin (SMA), desmin, and calponin, but is generally negative for h-caldesmon-a marker traditionally considered helpful in distinguishing fibromatosis from tumors with true smooth muscle differentiation. A 22-year-old woman presented with a left breast mass initially diagnosed as fibroadenoma on biopsy. Surgical excision revealed bland spindle cells within a collagenous stroma and infiltrative borders. Immunohistochemistry demonstrated positivity for h-caldesmon, nuclear β-catenin, and calponin. Molecular analysis confirmed an activating <i>CTNNB1</i> mutation, establishing the diagnosis of fibromatosis.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261482140"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136606","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":"Extranodal Extension in Colorectal Cancer: Association With Nodal Burden and Disease Recurrence.","authors":"Ezgi Hacihasanoglu, Aysegul Isal Arslan, Ali Ediz Kivanc","doi":"10.1177/10668969261483649","DOIUrl":"https://doi.org/10.1177/10668969261483649","url":null,"abstract":"<p><p>BackgroundExtranodal extension, defined as tumor invasion beyond the lymph node capsule into perinodal adipose tissue, has been associated with adverse outcomes in several malignancies but is not included in the AJCC-TNM staging system for colorectal cancer. This study evaluated the clinicopathological and prognostic significance of extranodal extension and its extent in lymph node-positive colorectal carcinoma.MethodsSixty-nine patients who underwent curative-intent resection for lymph node-positive colorectal carcinoma were retrospectively analyzed. Patients were classified according to the presence of extranodal extension, and extranodal extension-positive tumors were further categorized as limited (<1 mm) or extensive (≥1 mm). Associations with clinicopathological variables and survival outcomes were analyzed using Cox proportional hazards regression models.ResultsExtranodal extension was identified in 29 patients (42%) and was associated with a higher metastatic lymph node count, higher N stage, and an increased incidence of distant metastasis (all <i>P</i> < .05). In multivariate analysis adjusted for T stage, N stage, and postoperative adjuvant chemotherapy, extranodal extension remained independently associated with shorter disease-free survival (hazard ratio 2.65; 95% confidence interval 1.10-6.38; <i>P</i> = .031). Extranodal extension was not independently associated with overall survival. Although the extent of extranodal extension correlated with nodal burden, it was not independently associated with survival outcomes.ConclusionExtranodal extension is associated with increased nodal tumor burden and independently predicts shorter disease-free survival in colorectal carcinoma. Routine assessment and reporting of extranodal extension may improve pathological risk stratification.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261483649"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136530","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":"Mismatch Repair Pathway, <i>MLH1, MSH2</i> and Mutations in Prostate Cancer.","authors":"Himanshu, Md Ali Osama, Lavleen Singh, Riyaz Ahmad Mir, Atul Batra, Ranjit K Sahoo, Brusabhanu Nayak, Amlesh Seth, Venkateswaran K Iyer","doi":"10.1177/10668969261483643","DOIUrl":"https://doi.org/10.1177/10668969261483643","url":null,"abstract":"<p><p>ObjectivesThe DNA mismatch repair (MMR) pathway preserves genomic stability by correcting replication errors, with <i>MLH1</i> and <i>MSH2</i> playing central roles in mismatch recognition and repair. Loss of these proteins results in microsatellite instability, increased mutational burden, and genomic instability, contributing to prostate cancer development and progression. Emerging evidence suggests that <i>MMR</i> alterations define a distinct and clinically relevant subset of prostate cancer.MethodsA narrative literature review was performed using PubMed, Scopus, and Google Scholar databases. Articles published in English up to January 2026 were screened using combinations of the keywords \"prostate cancer,\" \"mismatch repair,\" \"MLH1,\" \"MSH2,\" \"microsatellite instability,\" and \"DNA repair.\" Original studies, clinical trials, genomic analyses and relevant review articles focusing on MMR alterations in prostate cancer were included.ResultsGermline MMR mutations are uncommon in prostate cancer; however, somatic alterations, particularly involving <i>MSH2</i> and less frequently <i>MLH</i>1, are enriched in advanced and metastatic disease. MMR-deficient tumors demonstrate high tumor mutational burden, increased neoantigen formation, enhanced immune infiltration, and upregulation of immune checkpoint molecules such as <i>PD-L1</i>, contributing to responsiveness to immunotherapy.Conclusion<i>MLH1</i> and <i>MSH2</i> alterations define a clinically significant molecular subtype of prostate cancer. Identification of MMR deficiency can guide immunotherapy selection, supporting the integration of molecular profiling into routine clinical practice.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261483643"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136614","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":"Identification of PAK Gene Fusions in an Ovarian and a Testicular Serous Carcinoma.","authors":"Nikka Khorsandi, Jeffry P Simko, W Patrick Devine, Cynthia Gasper, Deepika Sirohi","doi":"10.1177/10668969261482144","DOIUrl":"https://doi.org/10.1177/10668969261482144","url":null,"abstract":"<p><p>This report describes two unique gonadal serous carcinomas, one low-grade serous carcinoma (LGSC) of the ovary and one serous carcinoma of the scrotum each harboring novel <i>PAK</i> gene fusions. The first patient with ovarian LGSC was identified to have a <i>PTPRM::PAK1</i> fusion, identifying <i>PTPRM</i> as a novel fusion partner for <i>PAK1</i>. The second patient with high-grade papillary serous carcinoma of the scrotum contained a <i>DLG1::PAK2</i> fusion. Neither fusion was detected by DNA next-generation sequencing (NGS), highlighting the importance of RNA-based methodologies in identifying gene fusions. Overexpression of <i>PAK1</i> and <i>PAK2</i> has been reported in ovarian malignancies, correlating with tumor progression and reduced patient survival, while the significance of the unique fusions reported here warrants further consideration in relation to tumorigenesis and clinical implications.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261482144"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136456","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":"<i>TFEB</i>-Amplified Renal Cell Carcinoma With Focal Rhabdoid Features, Hyaline Globules, Giant Tumor Cells, and Osseous Metaplasia.","authors":"Linjie Xiong, Ting Zhao, Chin-Lee Wu","doi":"10.1177/10668969261489621","DOIUrl":"https://doi.org/10.1177/10668969261489621","url":null,"abstract":"<p><p><i>TFEB</i>-amplified renal cell carcinoma (RCC) is a rare, molecularly defined RCC, characterized by amplification of the <i>TFEB</i> gene on chromosome 6p21.1, with fewer than 100 tumors reported to date. Herein, we report a <i>TFEB</i>-amplified RCC with focal rhabdoid features, hyaline globules, giant tumor cells, and osseous metaplasia. This tumor further expands the histological spectrum of <i>TFEB</i>-amplified RCC. A 59-year-old man underwent radical nephrectomy for a 7.6-cm left renal mass. Histologically, the tumor demonstrated predominantly papillary architecture (90%) with focal solid areas (10%). Tumor cells showed voluminous eosinophilic cytoplasm and prominent nucleoli. Additional findings included multifocal rhabdoid features (10%), intracellular hyaline globules, giant tumor cells, occasionally with multinucleation, osseous metaplasia, psammomatous calcifications, and focal tumor necrosis (5%). The tumor was classified as World Health Organization (WHO)/International Society of Urological Pathology (ISUP) grade 4 and staged as pT2aNx. Immunohistochemically, the tumor cells were positive for PAX8, AMACR, and HNF1β, with rare Melan-A expression, and negative for keratin 7, CA9, GATA3, p63, ALK, cathepsin K, HMB45, and TFE3. RCC not otherwise specified (NOS) was initially diagnosed, and molecular testing was subsequently performed to further assist in the diagnosis. Chromosomal microarray analysis demonstrated amplification of chromosome 6p21.1 involving <i>TFEB</i> and other genes with a reported copy number of ≥7, which was confirmed by fluorescence in situ hybridization demonstrating <i>TFEB</i> copy-number gain with up to 9 <i>TFEB</i> signals per nucleus. Based on the morphology, immunoprofile, and molecular findings, the tumor was classified as <i>TFEB</i>-amplified RCC. The patient subsequently developed widespread metastatic disease and received radiotherapy and systemic treatment. He remains alive with progression of disease at 45 months of follow-up.</p>","PeriodicalId":14416,"journal":{"name":"International Journal of Surgical Pathology","volume":" ","pages":"10668969261489621"},"PeriodicalIF":0.9,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149136544","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}