Detection of RAS p.Q61R by Immunohistochemistry in Practice: A Clinicopathologic Study of 217 Thyroid Nodules with Molecular Correlates.

RAS p.Q61R is the most prevalent hot-spot mutation in RAS and RAS-like mutated thyroid nodules. A few studies evaluated RAS p.

Cytologic features of differentiated high-grade thyroid carcinoma: A multi-institutional study of 40 cases.

Background: Differentiated high-grade thyroid carcinoma (DHGTC) is recently recognized by the World Health Organization (WHO) as a subgroup of thyroid carcinomas with high-grade features while retaining the architectural and/or cytologic features of well-differentiated follicular-cell-derived tumors. The cytomorphology of DHGTC is not well documented despite potential implications for patient triage and management.

Methods: The pathology archives of six institutions were searched for cases diagnosed on resection as "high-grade thyroid carcinoma" using WHO criteria.

Defining the Role of mTORC1 in Thyrocytes by Studying the TSC2 Conditional Knockout Mouse Model.

The thyroid gland is susceptible to abnormal epithelial cell growth, often resulting in thyroid dysfunction. The serine-threonine protein kinase mechanistic target of rapamycin (mTOR) regulates cellular metabolism, proliferation, and growth through two different protein complexes, mTORC1 and mTORC2. The PI3K-Akt-mTORC1 pathway's overactivity is well associated with heightened aggressiveness in thyroid cancer, but recent studies indicate the involvement of mTORC2 as well.

Expanding Our Knowledge of Gene Alterations and Their Role in Thyroid Diseases.

Mutations in , a gene involved in RNA interference, have been associated with a wide range of multi-organ neoplastic and non-neoplastic conditions. Historically known for its association with pleuropulmonary blastoma, DICER1 syndrome has received more attention due to the association with newly discovered diseases and tumors. Recent studies evaluating mutations and DICER1-driven thyroid disease in both pediatric and adult thyroid nodules revealed thyroid disease as the most common manifestation of mutations.

Para This, Fibromin That: The Role of CDC73 in Parathyroid Tumors and Familial Tumor Syndromes.

CDC73 alterations are associated with three main parathyroid lesions according to the World Health Organization (WHO) classification of tumors of the endocrine system. These include hyperparathyroidism-jaw tumor (HPT-JT) syndrome-associated adenomas, atypical parathyroid tumors (APTs), and parathyroid carcinomas (PCs). The loss of nuclear parafibromin expression, which serves as a surrogate marker for the underlying CDC73 alteration, encompasses these tumors under the term parafibromin-deficient parathyroid tumors.

Thyroblastoma: A DICER1-associated embryonal neoplasm and fine needle aspiration diagnostic criteria.

Thyroblastoma is a rare, aggressive embryonal thyroid neoplasm associated with DICER1 mutation. It usually presents as a rapidly growing thyroid mass diffusely infiltrating the thyroid lobes and extending into perithyroidal tissue. Most thyroblastomas were initially diagnosed as malignant teratoma or carcinosarcoma.

Primary Thyroid Neoplasm with Fetal Morphology Associated with Mutations: Expanding the Diagnostic Profile of Thyroblastoma.

Thyroblastoma, a primary thyroid neoplasm with histological features of primitive thyroid tissue has recently been described and is included as a distinct entity in the most recent edition of the World Health Organization (WHO) Classification of Tumors (5th edition). In this study, we expand the clinical, morphological, and molecular profile of this aggressive neoplasm. The patients are females, 19 and 45 years of age, referred for large thyroid nodules.

The Classic, the Trendy, and the Refashioned: A Primer for Pathologists on What Is New in Familial Endocrine Tumor Syndromes.

Familial endocrine tumor syndromes are continuously expanding owing to the growing role of genetic testing in routine clinical practice. Pathologists are usually the first on the clinical team to encounter these syndromes at their initial presentation; thus, recognizing them is becoming more pivotal in routine pathology practice to help in properly planning management and further family testing. Our increasing knowledge about them is reflected in the newer syndromes included in the new World Health Organization classification and in the evolving discovery of new endocrine tumors and new familial associations.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Familial Tumor Syndromes.

The initiative of the 5th edition of the WHO classification of the Head and Neck Tumours establishing a new section dedicated to familial/heritable tumor syndromes with tumors and lesions in the head and neck region was much needed to better understand the tumours, diseases, and associated syndromes, as well as establish recommendations for monitoring and treating these patients. (WHO Classification of Tumours Editorial Board. Head and Neck tumours.

Overview of the 2022 WHO Classification of Familial Endocrine Tumor Syndromes.

This review of the familial tumor syndromes involving the endocrine organs is focused on discussing the main updates on the upcoming fifth edition of the WHO Classification of Endocrine and Neuroendocrine Tumors. This review emphasizes updates on histopathological and molecular genetics aspects of the most important syndromes involving the endocrine organs. We describe the newly defined Familial Cancer Syndromes as MAFA-related, MEN4, and MEN5 as well as the newly reported pathological findings in DICER1 syndrome.

Changes in Surgical Pathology Case Volume and Amendment Rates During the COVID-19 Pandemic.

Objectives: Surgical pathology volume decreased during the peak of the coronavirus disease 2019 (COVID-19) pandemic. We looked at the 4 months with the greatest reduction in surgical pathology volume during the COVID-19 pandemic and compared them with those same months in 2019 to determine changes in specimen volume. We compared the amendment rates during those periods and types of amendments issued (identification [ID], report defect [RD], diagnostic information [DI]).

Solid Thyroid Follicular Nodules With Longitudinal Nuclear Grooves.

Context.—: Follicular thyroid nodules can be a source of diagnostic difficulties, particularly when they display atypical features commonly associated with malignancy, such as nuclear grooves.

Objective.

Cribriform-Morular Thyroid Carcinoma Is a Distinct Thyroid Malignancy of Uncertain Cytogenesis.

Tumors with papillary cribriform and morular architecture were initially considered to be variants of papillary thyroid carcinoma; however, recent observations have challenged this view. In this study, we reviewed the demographical, histopathological, and immunohistochemical features of the largest case series, consisting of 33 tumors. The age at time of pathological diagnosis ranged from 18 to 59 (mean 33) years, and all patients except one were female.

Intraductal carcinoma of the salivary gland with NCOA4-RET: expanding the morphologic spectrum and an algorithmic diagnostic approach.

After the publication of the 2017 World Health Organization Classification of Head and Neck Tumours, there has been increasing interest in the classification of newly categorized intraductal carcinomas. Intraductal carcinoma (IC) is an indolent tumor, typically arising in the parotid gland, with an intact myoepithelial layer and a cystic, papillary, often cribriform architecture. Early studies of IC identified a heterogeneous group of molecular alterations driving neoplasia, and recent studies have defined three primary morphological/immunohistochemical variants, subsequently linking these morphologic variants with defined molecular signatures.

Genomics and Epigenomics of Medullary Thyroid Carcinoma: From Sporadic Disease to Familial Manifestations.

Our understanding of the genomics and epigenomics of medullary thyroid carcinoma (MTC) has advanced since the initial recognition of RET as a driver of MTC tumorigenesis in familial MTC. We now have insight into the frequency and prognostic significance of specific RET mutations in sporadic MTC. For example, the most common RET mutation in sporadic MTC is the RET Met918Thr mutation, the same mutation that underlies MEN2B and a poor prognosticator.

Clinicopathologic features of kinase fusion-related thyroid carcinomas: an integrative analysis with molecular characterization.

The discovery of actionable kinase gene rearrangements has revolutionized the therapeutic landscape of thyroid carcinomas. Unsolved challenges include histopathologic recognition of targetable cases, correlation between genotypes and tumor behavior, and evolving resistance mechanisms against kinase inhibitors (KI). We present 62 kinase fusion-positive thyroid carcinomas (KFTC), including 57 papillary thyroid carcinomas (PTC), two poorly differentiated thyroid carcinomas (PDTC), two undifferentiated thyroid carcinomas (ATC), and one primary secretory carcinoma (SC), in 57 adults and 5 adolescents.

Salivary-Like Tumors of the Thyroid: A Comprehensive Review of Three Rare Carcinomas.

Thyroid carcinomas represent 3.2% of all new cases of cancer in the United States. Whereas most thyroid tumors arise from follicular cells or, less commonly, parafollicular cells, the derivation of some rare primary thyroid carcinoma subtypes is less clear and represents an area of evolving knowledge.