8,270 results match your criteria American Journal Of Surgical Pathology[Journal]

Prominent Pseudoacini in Focal Nodular Hyperplasia: A Potential Diagnostic Pitfall.

Am J Surg Pathol 2022 Jun 22. Epub 2022 Jun 22.

Department of Pathology, Yale School of Medicine, New Haven, CT.

Pseudoacini are generally a morphologic feature of hepatocellular carcinoma (HCC), being absent or rare in benign hepatocytic tumors, such as hepatocellular adenoma. However, rarely these can be seen in focal nodular hyperplasia (FNH) and may pose diagnostic challenges, especially when prominent. The study was aimed to evaluate the occurrence of pseudoacini in FNH and their clinicopathologic correlations. Read More

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Superficial CD34-Positive Fibroblastic Tumor: A Clinicopathologic, Immunohistochemical, and Molecular Study of 59 Cases.

Am J Surg Pathol 2022 Jun 20. Epub 2022 Jun 20.

Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.

Superficial CD34-positive fibroblastic tumor (SCD34FT) is a rare soft tissue neoplasm that shows overlapping features with PRDM10-rearranged soft tissue tumor (PRDM10-STT). This study characterizes the clinicopathologic, immunohistochemical, and molecular features of SCD34FT in a series of 59 cases. Fluorescence in situ hybridization to assess for PRDM10 rearrangement was performed in 12 tumors. Read More

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Localized Malignant Peritoneal Mesothelioma (LMPeM) in Women: A Clinicopathologic Study of 18 Cases.

Am J Surg Pathol 2022 Jun 20. Epub 2022 Jun 20.

Departments of Pathology.

Localized malignant peritoneal mesothelioma is a rare tumor with limited information in the literature. In this study, we present our experience with 18 cases seen in our hospital over a period of 43 years (1978 to 2021). Patients' median age was 55 years (y) (range: 33 to 79 y) and most of them were Caucasians. Read More

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NTRK-Rearranged Uterine Sarcomas: Clinicopathologic Features of 15 Cases, Literature Review, and Risk Stratification.

Am J Surg Pathol 2022 Jun 20. Epub 2022 Jun 20.

Division of Women's and Perinatal Pathology, Department of Pathology, Brigham and Women's Hospital, Boston, MA.

NTRK-rearranged uterine sarcomas are rare spindle cell neoplasms that typically arise in the uterine cervix of young women. Some tumors recur or metastasize, but features which predict behavior have not been identified to date. Distinguishing these tumors from morphologic mimics is significant because patients with advanced stage disease may be treated with TRK inhibitors. Read More

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Gastroesophageal Glomus Tumors: Clinicopathologic and Molecular Genetic Analysis of 26 Cases With a Proposal for Malignancy Criteria.

Am J Surg Pathol 2022 Jun 15. Epub 2022 Jun 15.

Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA.

Although criteria for malignancy have been established for glomus tumors of soft tissue, there are no accepted criteria for gastroesophageal glomus tumors, the behavior of which is considered to be unpredictable. Recently, both benign and aggressive gastroesophageal glomus tumors have been shown to harbor CARMN::NOTCH2 fusions, but, as yet, there are no described genetic features that predict clinical behavior. Here, we evaluated 26 gastroesophageal glomus tumors to investigate histologic and genetic features that might predict malignant behavior. Read More

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Clinicopathologic and Immunohistochemical Characterization of Sarcomatoid Chromophobe Renal Cell Carcinoma: An Analysis of 22 Cases.

Am J Surg Pathol 2022 Jun 13. Epub 2022 Jun 13.

Departments of Pathology and Laboratory Medicine.

Sarcomatoid differentiation in chromophobe renal cell carcinoma (ChRCC) is a rare finding and a significant predictor of worse outcomes. When the sarcomatoid component overgrows the conventional component or is the only component on a biopsy, the differential diagnoses encompass a variety of entities. Therefore, we reviewed 22 sarcomatoid ChRCCs and characterized the immunophenotype. Read More

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"Malignant Mesenchymoma" Revisited: A Clinicopathologic Study of Leiomyosarcomas With Osteosarcomatous Differentiation.

Am J Surg Pathol 2022 Jun 13. Epub 2022 Jun 13.

Brigham and Women's Hospital, Harvard Medical School, Boston, MA.

Leiomyosarcoma (LMS) is the most common sarcoma in adults. Rarely, LMS dedifferentiates into an undifferentiated sarcoma. Very few cases of LMS with heterologous osteosarcomatous differentiation (OS) have been reported. Read More

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Neoadjuvant Radiation in High-Grade Soft-Tissue Sarcomas: Histopathologic Features and Response Evaluation.

Am J Surg Pathol 2022 Jun 3. Epub 2022 Jun 3.

Institute of Pathology, Technical University of Munich.

In this study, we sought to determine the prognostic value of both the European Organization for Research and Treatment of Cancer-Soft Tissue and Bone Sarcoma Group (EORTC-STBSG) score and the histologic parameters viable tumor, coagulative necrosis, hyalinization/fibrosis, and infarction in patients (n=64) with localized, nonmetastatic high-grade soft-tissue sarcomas after preoperative radiomonotherapy. A standardized macroscopic workup for pretreated surgical specimen including evaluation of a whole section of high-grade soft tissue sarcomas in the largest diameter, was used. Association with overall survival and disease-free survival was assessed. Read More

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GRM1 Immunohistochemistry Distinguishes Chondromyxoid Fibroma From its Histologic Mimics.

Am J Surg Pathol 2022 Jun 1. Epub 2022 Jun 1.

Department of Pathology, Stanford University School of Medicine, Stanford, CA.

Chondromyxoid fibroma (CMF) is a rare benign bone neoplasm that manifests histologically as a lobular proliferation of stellate to spindle-shaped cells in a myxoid background, exhibiting morphologic overlap with other cartilaginous and myxoid tumors of bone. CMF is characterized by recurrent genetic rearrangements that place the glutamate receptor gene GRM1 under the regulatory control of a constitutively active promoter, leading to increased gene expression. Here, we explore the diagnostic utility of GRM1 immunohistochemistry as a surrogate marker for GRM1 rearrangement using a commercially available monoclonal antibody in a study of 230 tumors, including 30 CMF cases represented by 35 specimens. Read More

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Clinicopathologic and Molecular Characterization of Epstein-Barr Virus-positive Plasmacytoma.

Am J Surg Pathol 2022 Jun 1. Epub 2022 Jun 1.

Hematopathology Section.

Epstein-Barr virus (EBV)-positive plasmacytoma is a rare plasma cell neoplasm. It remains unclear whether EBV-positive plasmacytoma represents a distinct entity or a variant of plasmacytoma. It shares morphologic features with plasmablastic lymphoma (PBL) and may cause diagnostic uncertainty. Read More

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Low-grade Fibromyxoid Sarcoma of the Vulva and Vagina: Clinical, Pathologic, and Molecular Characterization of 7 Cases and Review of the Literature.

Am J Surg Pathol 2022 Apr 13. Epub 2022 Apr 13.

Division of Women's and Perinatal Pathology.

Low-grade fibromyxoid sarcoma (LGFMS) is a malignancy with propensity for late relapse that principally affects deep soft tissues of the extremities and trunk. Its occurrence in the lower female genital tract is rare, and thus it may not be always considered in the differential diagnosis. We describe the salient features of 7 vulvovaginal LGFMS identified in the authors' consultation files. Read More

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A Novel Combined Tumor Budding-Poorly Differentiated Clusters Grading System Predicts Recurrence and Survival in Stage I-III Colorectal Cancer.

Am J Surg Pathol 2022 May 25. Epub 2022 May 25.

Department of Pathology and Laboratory Medicine.

Tumor budding (TB) and poorly differentiated clusters (PDCs) are powerful prognostic factors in colorectal cancer (CRC). Despite their morphologic and biological overlap, TB and PDC are assessed separately and are distinguished by an arbitrary cutoff for cell cluster size. This cutoff can be challenging to apply in practice and its biological significance remains unclear. Read More

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Enhanced PD-L1 Expression in LMP1-positive Cells of Epstein-Barr Virus-associated Malignant Lymphomas and Lymphoproliferative Disorders: A Single-cell Resolution Analysis With Multiplex Fluorescence Immunohistochemistry and In Situ Hybridization.

Am J Surg Pathol 2022 May 24. Epub 2022 May 24.

Department of Pathology.

Epstein-Barr virus (EBV) is associated with various types of human malignancies and with programmed death ligand (PD-L) 1 expression in neoplastic cells. However, in EBV-associated malignant lymphomas and lymphoproliferative disorders (LPDs), there is limited information regarding PD-L1 expression profiles among different histologic types and patterns of EBV latency. First, we investigated PD-L1 and EBV latent gene expression using conventional immunohistochemistry and in situ hybridization in 42 EBV-associated malignant lymphomas and LPDs. Read More

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Recurrent KAT6B/A::KANSL1 Fusions Characterize a Potentially Aggressive Uterine Sarcoma Morphologically Overlapping With Low-grade Endometrial Stromal Sarcoma.

Am J Surg Pathol 2022 May 17. Epub 2022 May 17.

Department of Pathology & Laboratory Medicine, Mount Sinai Hospital.

With the widespread application of next-generation sequencing, the genetic landscape of uterine mesenchymal neoplasms has been evolving rapidly to include several recently identified fusion genes. Although chromosomal rearrangements involving the 10q22 and 17q21.31 loci have been reported in occasional uterine leiomyomas decades ago, the corresponding KAT6B::KANSL1 fusion has been only recently identified in 2 uterine tumors diagnosed as leiomyoma and leiomyosarcoma. Read More

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Nodular Lymphocyte-predominant Hodgkin Lymphoma With Nodular Sclerosis: An Underrecognized Feature Associated With Pattern D.

Am J Surg Pathol 2022 May 16. Epub 2022 May 16.

Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX.

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) with unusual features, including some that can overlap morphologically with classic Hodgkin lymphoma (CHL), have been described. Herein, we describe 12 cases of NLPHL with fibrous bands and capsular fibrosis resembling, in part, nodular sclerosis (NS) CHL. Seven of 12 cases harbored Reed-Sternberg-like cells, further suggestive of CHL, but all cases lacked associated eosinophils and/or plasma cells in the background. Read More

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Targeted Next-generation Sequencing Reveals a Wide Morphologic and Immunophenotypic Spectrum of Monomorphic Epitheliotropic Intestinal T-Cell Lymphoma.

Am J Surg Pathol 2022 May 12. Epub 2022 May 12.

Department of Pathology, Chi-Mei Medical Center, Tainan.

Primary intestinal T-cell lymphoma (PITL) is highly aggressive and includes celiac disease-related enteropathy-associated T-cell lymphoma (EATL), monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), and primary intestinal peripheral T-cell lymphoma, not otherwise specified (ITCL-NOS). MEITL is the most common PITL in Asia, comprising of monomorphic medium-sized cells typically expressing CD8, CD56, and cytotoxic granules. Occasional cases with intermediate features between MEITL and ITCL-NOS are difficult to be classified and warrant further investigation. Read More

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DNA Mismatch Repair-deficient Rectal Cancer Is Frequently Associated With Lynch Syndrome and With Poor Response to Neoadjuvant Therapy.

Am J Surg Pathol 2022 May 13. Epub 2022 May 13.

Departments of Pathology.

We evaluated 368 consecutively resected rectal cancers with neoadjuvant therapy for DNA mismatch repair (MMR) protein status, tumor response to neoadjuvant therapy, histopathologic features, and patient survival. Nine (2.4%) rectal cancers were mismatch repair-deficient (MMRD): 8 (89%) Lynch syndrome-associated tumors and 1 (11%) sporadic MLH1-deficient tumor. Read More

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MYB RNA In Situ Hybridization Is a Useful Diagnostic Tool to Distinguish Breast Adenoid Cystic Carcinoma From Other Triple-negative Breast Carcinomas.

Am J Surg Pathol 2022 Jul 9;46(7):878-888. Epub 2022 May 9.

Departments of Pathology.

Breast adenoid cystic carcinoma (AdCC) has overlapping features with basal-like triple-negative breast carcinoma (TNBC), yet carries a more favorable prognosis, and accurate diagnosis is critical. Like salivary gland AdCC, breast AdCC demonstrates recurrent alterations in the MYB gene. Novel chromogenic RNA in situ hybridization (ISH) for MYB has emerged as sensitive and specific for salivary gland AdCC. Read More

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Endometrial Stromal Sarcomas With BCOR Internal Tandem Duplication and Variant BCOR/BCORL1 Rearrangements Resemble High-grade Endometrial Stromal Sarcomas With Recurrent CDK4 Pathway Alterations and MDM2 Amplifications.

Am J Surg Pathol 2022 May 3. Epub 2022 May 3.

Department of Pathology and Laboratory Medicine, Sinai Health System and University of Toronto.

The distinction between low-grade and high-grade endometrial stromal sarcomas (LGESS, HGESS) is increasingly defined by genetics. Recently, variant genomic alterations involving BCOR or BCORL1 have been reported in endometrial stromal sarcoma (ESS), although it remains unclear whether these justify a diagnosis of LGESS or HGESS. In this study, we describe clinicopathologic and molecular features of ESS with such alterations to help clarify their classification in the spectrum of ESS. Read More

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IDH1/2 Mutations in Sinonasal Undifferentiated Carcinomas: Previously Undescribed IDH2 R172K and R140x Variants.

Am J Surg Pathol 2022 May 2. Epub 2022 May 2.

Departments ofPathology.

Sinonasal undifferentiated carcinoma (SNUC) is a rare, poorly defined sinonasal epithelial neoplasm from which several genetically defined entities are emerging.IDH1/2mutations were recently identified in a subset of SNUC. However, the ideal method for the detection of these mutations remains to be established. Read More

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Intraductal Carcinoma of the Prostate: Extreme Nuclear Size Is Not a Diagnostic Parameter.

Am J Surg Pathol 2022 Apr 28. Epub 2022 Apr 28.

Departments of Pathology, Urology, and Oncology, The Johns Hopkins Medical Institutions, Maryland, MD.

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Liposarcoma With Hibernoma-like Histology: A Clinicopathologic Study of 16 Cases.

Am J Surg Pathol 2022 Apr 27. Epub 2022 Apr 27.

Departments ofDiagnostic Pathology.

Hibernoma is an uncommon benign tumor of brown fat cells that consistently expresses uncoupling protein 1 (UCP1). Herein, we clinicopathologically characterized 16 liposarcomas, for which histology, at least focally, closely resembled that of hibernoma, including sheets of brown fat-like, finely multivacuolated-to-eosinophilic tumor cells with no or minimal nuclear atypia. The cohort consisted of 4 well-differentiated liposarcomas (WDLSs), 6 dedifferentiated liposarcomas with a concomitant WDLS component, and 6 myxoid liposarcomas (MLSs). Read More

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SMARCB1-deficient and SMARCA4-deficient Malignant Brain Tumors With Complex Copy Number Alterations andTP53Mutations May Represent the First Clinical Manifestation of Li-Fraumeni Syndrome.

Am J Surg Pathol 2022 Apr 22. Epub 2022 Apr 22.

Swabian Childrens' Cancer Center, University Hospital Augsburg and EU-RHAB Registry.

Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant central nervous system tumor predominantly affecting infants. Mutations ofSMARCB1or (rarely)SMARCA4causing loss of nuclear SMARCB1 or SMARCA4 protein expression are characteristic features, but further recurrent genetic alterations are lacking. Most AT/RTs occur de novo, but secondary AT/RTs arising from other central nervous system tumors have been reported. Read More

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Comprehensive Clinical, Histopathologic, and Molecular Analysis and Long-term Follow-up of Patients With Nodal Blue Nevi.

Am J Surg Pathol 2022 Apr 20. Epub 2022 Apr 20.

Melanoma Institute Australia.

Blue nevi are benign, melanocytic neoplasms that show a range of clinical and morphologic patterns and include common/dendritic, cellular, and atypical cellular subtypes. Like other nevi, they most commonly occur in skin but can occasionally involve lymph nodes where they may be misinterpreted as representing metastatic melanoma. Moreover, whether benign blue nevi can metastasize to lymph nodes and their natural history and prognostic significance has been the subject of great controversy. Read More

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Histopathologic and Molecular Characterization of Uterine Leiomyoma-like Inflammatory Myofibroblastic Tumor: Comparison to Molecular Subtypes of Uterine Leiomyoma.

Am J Surg Pathol 2022 Apr 18. Epub 2022 Apr 18.

Department of Medical and Clinical Genetics.

Uterine leiomyoma (UL) is a common benign neoplasm which can sometimes be difficult to differentiate from the uterine inflammatory myofibroblastic tumor (IMT) based on morphology alone. IMT is a myofibroblastic/fibroblastic neoplasm which has typically been considered to be rare in the uterus. Its clinical behavior is usually indolent although aggressive variants exist. Read More

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Sinonasal Tumors With Neuroepithelial Differentiation (Olfactory Carcinoma): Delineation of Their Pathologic and Clinical Features With Insights into Their Relationship to Olfactory Neuroblastoma and Sinonasal Carcinoma.

Am J Surg Pathol 2022 Apr 15. Epub 2022 Apr 15.

Department of Pathology, Icahn School of Medicine at Mount Sinai Hospital, New York, NY.

Olfactory carcinoma is one of many names applied to sinonasal malignancies with histologic similarity to olfactory neuroblastoma (ONB) but cytokeratin expression or gland formation. It is unclear whether these neuroepithelial tumors represent a unified category and if they are separate from ONB and currently-recognized sinonasal carcinomas. This study aims to explore their clinicopathologic characteristics based on a large collective experience. Read More

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Diffuse Midline Gliomas With Histone H3 K27M Mutation in Adults and Children: A Retrospective Series of 164 Cases.

Am J Surg Pathol 2022 06 13;46(6):863-871. Epub 2022 Apr 13.

Department of Pathology, National Key Laboratory of Biotherapy.

Diffuse midline glioma, H3 K27M-mutant (H3 K27M-mt DMG), is a rare and highly aggressive tumor that is more common in children than in adults. Few studies have compared the differences between pediatric and adult patients with this rare tumor. We here report our retrospective study of 94 adult and 70 pediatric cases of diffuse midline glioma. Read More

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Association Between Loss of SATB2 Expression in Inflammatory Bowel Disease Indefinite for Dysplasia and a Diagnosis of Definitive Dysplasia on Follow-up.

Am J Surg Pathol 2022 Apr 12. Epub 2022 Apr 12.

Departments ofPathology.

Special AT-rich sequence-binding protein 2 (SATB2) is a sensitive and specific biomarker for sporadic colonic adenocarcinomas. Previous studies have found that SATB2 is lost in some adenocarcinomas and dysplasias associated with inflammatory bowel disease (IBD). In establishing these findings, the prior studies did not examine cases of IBD interpreted as indefinite for dysplasia. Read More

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Mucinous Tumor Coexisting With Mesonephric-like Proliferation/Tumor in the Ovary: A Novel Association.

Am J Surg Pathol 2022 Apr 12. Epub 2022 Apr 12.

Departments ofPathology.

The literature indicates that mesonephric carcinoma (MC) and mesonephric-like adenocarcinoma (MLA) typically lack mucinous and squamous features/differentiation. We report 4 cases of ovarian mucinous tumors (1 mucinous cystadenofibroma and 3 mucinous borderline tumors/atypical proliferative mucinous tumors [MBT/APMT]) co-existing with mesonephric-like lesions which were highlighted by Gata3 and Pax8 expression. All cases contained benign mesonephric-like proliferations (MLP) which focally displayed gastrointestinal-type mucinous metaplasia/differentiation and some were intimately admixed with mucinous glands associated with the mucinous tumor. Read More

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Gastrointestinal Tract Injury by Yttrium-90 Appears Largely Restricted to Resin Microspheres But Can Occur Years After Embolization.

Am J Surg Pathol 2022 Apr 8. Epub 2022 Apr 8.

Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA.

Radioembolization therapy utilizes yttrium-90 (Y90) impregnated resin (SIR-Spheres) or glass (TheraSpheres) microspheres to selectively target hepatic lesions via transarterial radioembolization. Occasional cases of gastrointestinal tract injury, secondary to nontargeted delivery of microspheres, have been reported, but large descriptive pathology series are lacking. We identified 20 cases of histologically confirmed mucosal injury associated with Y90 from 17 patients and assessed the corresponding clinical and pathologic sequelae. Read More

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