Sialadenopapillary Ductal Tumors: Unifying the Spectrum of Sialadenoma Papilliferum-like Tumors With Low Malignant Potential.

Sialadenoma papilliferum is a tumor characterized by surface papillary projections and glandular/microcystic proliferation at the lesion base. Cases in which surface involvement is absent have been termed "sialadenoma papilliferum-like intraductal papillary tumor." Similar tumors that are present in the mandible have been termed "tubulopapillary hidradenoma-like tumor of the mandible.

Parsing the thyroid cytopathology suspicious for malignancy diagnosis through molecular-derived risk of malignancy and other related parameters: Insights into nodule characteristics and practice patterns.

Introduction: Thyroid cytopathology cases with suspicious for malignancy (SFM) diagnosis often result in resection. However, molecular testing offers details that may provide additional insights. In this study, the molecular profiles of SFM cases from two institutions that routinely used ThyroSeq v3 (TSV3) were examined.

Performance Characteristics of Incisional and Core Needle Biopsies for Diagnosis in Parotid Gland: Single-Institutional Experience and Assessment of the Value of a Milan System for Reporting Salivary Gland Cytopathology-Like Risk Stratification Model.

Context.—: Unlike parotid fine-needle aspiration biopsy, standardized reporting for core needle biopsy (CNB) and incisional biopsy (IB) is not established.

Objective.

A Novel Scoring System for MYB RNA In Situ Hybridization Displays High Sensitivity and Specificity for Adenoid Cystic Carcinoma in a Clinical Setting.

Background: MYB RNA in situ hybridization (ISH) has emerged as a reliable and accessible marker to support adenoid cystic carcinoma (ACC) diagnosis, though still not well studied. Here, we report our results in a validation and prospective cohort to improve MYB RNA ISH diagnostic accuracy.

Methods: 79 cases (23 retrospective and 56 prospective) underwent MYB RNA ISH testing (44 ACC and 35 non-ACC).

Acinic cell Carcinoma with high-grade Squamoglandular and Chondrosarcomatous Transformation Mimicking 'Carcinosarcoma ex-pleomorphic Adenoma': A Wrinkle in the Proposed Nomenclature Revision for Sarcomatoid Salivary Gland Neoplasms.

While acinic cell carcinoma (AciCC) can undergo high-grade transformation (HGT) to high-grade adenocarcinoma or poorly differentiated carcinoma, other morphologies such as spindle cell/sarcomatoid carcinoma are rare and not well-characterized. We herein report a novel case of AciCC with squamoglandular and chondrosarcomatous HGT mimicking a so-called 'carcinosarcoma ex-pleomorphic adenoma'. The patient is an 81-year-old male with a two-month history of neck swelling and referred otalgia who presented with a left parapharyngeal space mass extending into retropharyngeal space and pterygoid muscles.

High-Grade Transformation and Carcinosarcoma: A Review of Two Forms of Advanced Progression in the Salivary Gland.

Context.—: High-grade transformation, previously known as dedifferentiation, in salivary gland carcinoma and carcinosarcoma ex pleomorphic adenoma is a rare phenomenon. It is, however, clinically relevant and affects treatment and prognosis.

The Journey to Improve the College of American Pathologists Cancer Biomarker Reporting Protocols.

Context.—: Biomarker reporting has increasingly become a key component of pathology reporting, providing diagnostic, prognostic, and actionable therapeutic data for patient care.

Objective.

Biphenotypic Sinonasal Sarcoma With High-Grade Features: A Diagnostic Challenge.

Biphenotypic sinonasal sarcoma (BSNS) is a rare neoplasm of the sinonasal tract. These tumors show neural and myogenic differentiation and are characterized by translocations. The immunophenotypic features reflect their dual differentiation.

Glomangiosarcoma-like Anaplastic Transformation in Papillary Thyroid Carcinoma: A Novel Form of Heterologous Differentiation and a Systematic Review of Heterologous Element Prevalence.

Anaplastic thyroid carcinoma (ATC) demonstrates a wide variety of morphologies and is characteristically associated with a differentiated thyroid carcinoma component. Heterologous differentiation is a rare, potentially challenging phenomenon in ATC, mostly observed as osteosarcomatous or chondrosarcomatous differentiation. We now describe a novel 'glomangiosarcoma-like' differentiation, review our archival experience from two institutions (UPMC, CC), and perform a systematic review for the prevalence of heterologous elements in ATC.

New Entities and Concepts in Salivary Gland Tumor Pathology: The Role of Molecular Alterations.

Context.—: Salivary gland tumors are rare tumor types for which the molecular understanding has resulted in a rapid expansion and shuffling of entities. These changes are reflected in the 5th edition World Health Organization Classification of Head and Neck Tumours (WHO 5th edition), although many nuances still remain.

Solitary sclerotic fibroma of the palpebral conjunctiva: a unique presentation of a rare entity.

Sclerotic fibroma (SF) is an uncommon yet benign tumor that may occasionally be associated with Cowden's disease that presents as an asymptomatic, well-circumscribed lesion. We present a rare case of a patient with a solitary SF of the palpebral conjunctiva. The patient was an 85-year-old male who presented with a right lower lid nodule that was initially treated as a chalazion.

Odontogenic Carcinosarcoma: Clinicopathologic and Molecular Features of Three Cases, a Literature Review and Nomenclature Proposal.

Background: Odontogenic carcinosarcoma (OCS) is a rare odontogenic malignancy with limited characterization and unexplored molecular features. We report clinicopathologic and molecular findings in 3 additional OCS and review the literature.

Methods: 3 OCS (5.

DOTATATE PET Imaging in Olfactory Neuroblastoma and Association with SSTR Expression.

 Olfactory neuroblastoma (ONB), or esthesioneuroblastoma, is a rare neuroectodermal tumor of the nasal cavity and paranasal sinuses. Most of these tumors express somatostatin receptors (SSTRs), providing a potential target for radionuclide imaging with Ga-68 DOTATATE. However, this imaging modality has not been extensively studied in ONB.

Epstein-Barr Virus-Associated Lymphoepithelial Carcinoma Arising in a Salivary Sebaceous Lymphadenoma.

Background: Lymphadenomas are rare benign tumors of the major salivary glands that are further classified as sebaceous and non-sebaceous. No association with viruses has been reported so far. Little is known about the mechanisms that allow lymphadenomas to undergo malignant transformation.

NKX3.1 Expression and Molecular Characterization of Secretory Myoepithelial Carcinoma (SMCA): Advancing the Case for a Salivary Mucous Acinar Phenotype.

Background: Secretory myoepithelial carcinomas (SMCA) are rare, mucinous, signet ring predominant tumors with primitive myoepithelial features. While many mucinous salivary gland tumors have now been molecularly characterized, key drivers in SMCA have yet to be elucidated. Recently, NKX3.

A thyroid EIF1AX story: how clinical, cytologic, and molecular surveillance led to appropriate management.

Introduction: Indeterminate thyroid cytology diagnoses are associated with intermediate risks of malignancy. Application of molecular testing (MT) to indeterminate specimens provides additional diagnostic and prognostic information. While a positive or suspicious MT result may prompt surgery, a negative MT result is associated with a low probability of cancer or noninvasive follicular thyroid neoplasm with papillary-like nuclear features and approximates that of a benign cytology diagnosis.