The American journal of surgical pathology

01 16 October 2026

DOI 10.1097/pas.0000000000002630

Whole-Exome and Whole-Genome Sequencing Identifies Driver CTNNB1 Mutations in Ossifying Renal Tumor of Infancy

Open DOI

Yifei Wang, Zhou Zhou, Xiaowei Li et al.

Ossifying renal tumor of infancy (ORTI) is an exceedingly rare pediatric renal neoplasm with an inherently benign clinical course. Although histomorphologically well-described, its underlying molecular pathogenesis remains largely unknow...

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02 16 October 2026

DOI 10.1097/pas.0000000000002629

Monomorphic Epitheliotropic Intestinal T-Cell Lymphoma

Open DOI

Keya Li, Ran Wei, Mingzhen Su et al.

Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare and aggressive T-cell lymphoma with incompletely characterized features. We analyzed 120 Chinese patients (88 males, 32 females; median age 58y), including 43% at s...

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03 14 October 2026

DOI 10.1097/pas.0000000000002632

Peritumoral Malignant Cellular Foci Performs Better Than Tumor Budding and Poorly Differentiated Cluster in Risk Stratification of Lymph Node Metastasis in pT1 Colorectal Cancer

Open DOI

Chaofeng Yuan, Chao Wang, Jiajun Lai et al.

As biomarkers separated by the arbitrary 5-tumor-cell cutoff at the tumor invasive front, tumor budding (TB) and poorly differentiated clusters (PDC) are recognized as high-risk factors for lymph node metastasis (LNM) in pT1 colorectal c...

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04 13 October 2026

DOI 10.1097/pas.0000000000002627

Musculoskeletal Histopathology of Klippel-Trénaunay Syndrome

Open DOI

Aarti E. Sharma, Igor Odintsov, Yin P. Hung et al.

Klippel-Trénaunay syndrome (KTS) is a rare congenital vascular-overgrowth disorder within the broader spectrum of PIK3CA -related overgrowth syndromes. Although clinical, radiologic, and orthopedic manifestations are well described, the ...

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05 12 October 2026

DOI 10.1097/pas.0000000000002634

Further Molecular Evidence Supporting the Neoplastic Nature of the Leydig Cells in Ovarian Sertoli-Leydig Cell Tumors

Open DOI

Clemence Scard, Alexis Trecourt, Francoise Descotes et al.

Was not provided for this article.

06 12 October 2026

DOI 10.1097/pas.0000000000002635

Recurrent PDGFRB-Mutations in the Epithelioid Variant of Fibrous Papules

Open DOI

Thibault Kervarrec, Ziyad Alsugair, Nicolas Macagno et al.

Fibrous papule (FP) is a common benign dermal mesenchymal lesion presenting as a solitary, dome-shaped papule mostly located on the nose. The morphologic spectrum is broad, and a number of variants have been described, including hypercel...

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07 12 October 2026

DOI 10.1097/pas.0000000000002633

Vulvovaginal Epithelioid Mesenchymal Neoplasm With “Deciduoid” Morphology

Open DOI

András Rókusz, Ayoma D. Attygalle, Zsombor Melegh et al.

A wide variety of mesenchymal lesions arise in the vulvovaginal region, some relatively site-specific. We report 4 cases of a novel vulvovaginal mesenchymal lesion, which we term vulvovaginal epithelioid mesenchymal neoplasm with “decidu...

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08 9 October 2026

DOI 10.1097/pas.0000000000002626

Diagnostic Utility of USP6 RNA Chromogenic In Situ Hybridization in the Differential Diagnosis of Nodular Fasciitis and Aneurysmal Bone Cyst

Open DOI

Margarita Muñoz de Toro, Jennifer Tan, Phoebe L. Li et al.

Recurrent USP6 gene rearrangements underlie a subset of mesenchymal neoplasms, including nodular fasciitis and aneurysmal bone cyst. These rearrangements place USP6 under the regulatory control of another gene's constitutively active pro...

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09 9 October 2026

DOI 10.1097/pas.0000000000002628

Clinicopathological Characteristics of Merkel Cell Carcinoma in Younger Patients

Open DOI

Jawad Aqeel, Joseph S. Durgin, Jasmine S. Saleh et al.

Merkel cell carcinoma (MCC) is a rare and aggressive cutaneous neuroendocrine carcinoma that predominantly affects older adults. MCC arising in younger patients is exceedingly rare, and its clinicopathologic features remain poorly descri...

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10 7 October 2026

DOI 10.1097/pas.0000000000002624

The 2026 World Health Organization Classification of Tumors of Soft Tissue and Bone

Open DOI

Jason L. Hornick, Judith V.M.G. Bovee, Cristina R. Antonescu et al.

The 6th edition of the World Health Organization Classification of Soft Tissue and Bone Tumors (STB6) integrates the latest scientific and molecular discoveries with decades of pathological expertise to establish a globally accepted comm...

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