Advances In Anatomic Pathology最新文献

Social media (SoMe) has become an integral tool in modern pathology, facilitating education, research, mentorship, and professional networking. However, the evolving landscape of SoMe platforms presents both opportunities and challenges for pathologists. Bluesky, a decentralized platform launched publically in 2024 has gained significant traction among pathologists as an alternative to "traditional," or more widely-used, platforms like Twitter/X. This narrative review explores the role of SoMe in pathology, introduces Bluesky and its pathology-focused community PathSky, and compares it with other platforms. In addition, practical guidance on joining Bluesky and engaging with PathSky is provided. By embracing innovative platforms like Bluesky, pathologists can enhance collaboration, education, and professional growth in the digital age.

Hepatoblastoma (HB), the most common primary malignant liver tumor of childhood, demonstrates remarkable histologic heterogeneity and can be classified into epithelial or mixed epithelial-mesenchymal subtypes. This review summarizes updates in histologic classification, molecular signatures, staging, and risk stratification of HB. The Children's Hepatic tumors International Collaboration represents an international effort to standardize the study of rare pediatric liver tumors; emphasis continues to remain on improving risk stratification by a combination of clinical, histologic, and molecular features to tailor treatment in a bid to reduce toxicity while maintaining or improving efficacy. Pure fetal HB is cured by complete resection without the need for adjuvant chemotherapy. Malignant rhabdoid tumors have been parsed out from small cell undifferentiated HBs by negative INI-1 staining on immunohistochemistry; these tumors require a distinct and more aggressive chemotherapeutic regimen. The significance of recently characterized "blastema" component in HB remains to be elucidated. Hepatocellular neoplasm, not otherwise specified, is a provisional diagnostic category for tumors exhibiting either intermediate or a combination of both HB and hepatocellular carcinoma histologic features. The Children's Hepatic tumors International Collaboration risk stratification algorithm includes age as an important discriminator of risk, in addition to AFP, metastasis, and PreTreatment EXTent of disease stage and its annotations.

Preneoplastic and neoplastic biliary disease comprises biliary intraepithelial neoplasia (BilIN), intraductal papillary neoplasms, mucinous cystic neoplasms (MCNs), and cholangiocarcinoma and their variants. Correct recognition of these entities can be challenging, especially on small/needle biopsies, but is required to plan therapy and guide transplant in the setting of cirrhosis. Salient histologic features of these entities, along with ancillary use of immunostains and key molecular findings aiding in diagnosis, are discussed. Type 2 intraductal papillary neoplasm of the bile ducts is typically associated with an invasive malignancy and lack unique molecular features associated with the Type 1 intraductal papillary neoplasm, thus they are called "papillary cholangiocarcinoma" by some authors. Some of the cholangiocarcinoma variants, like enteroblastic and mucoepidermoid, are under-recognized and can pose diagnostic challenges. The tubulocystic and cholangioblastic variants are relatively recently described but are being increasingly recognized. The cholangioblastic variant has a novel NIBPL-NACC1 fusion described in the more recent larger series reported, making it a somewhat unique variant of cholangiocarcinoma. Nomenclature of the cholangioblastic variant is in evolution as is the link between adenofibroma and the tubulocystic variant. Correct recognition of these variant subtypes would aid in long-term studies to better determine the prognosis in these subtypes.

Primary liver carcinoma (PLC) is the sixth most common malignancy worldwide and the third leading cause of cancer-related mortalities. Hepatocellular carcinoma (HCC) is the most prevalent form of PLC, followed by intrahepatic cholangiocarcinoma (iCCA). In addition, there is a group of rarer PLCs that do not fit neatly into the HCC or iCCA categories. This review explores this heterogeneous group, including combined hepatocellular-cholangiocarcinoma (cHCC-CCA), intermediate cell carcinoma (ICC), mixed hepatocellular-neuroendocrine carcinoma, and undifferentiated primary liver carcinoma. cHCC-CCA is a rare subtype of PLC, characterized by both hepatocytic and cholangiocytic differentiation within the same tumor. The latest WHO classification (2019, fifth edition) redefined cHCC-CCA by eliminating the "stem cell subtypes" and emphasized that diagnosis should primarily rely on morphologic features, supported by immunohistochemical staining to better define subtypes. Intermediate cell carcinoma is a subtype of cHCC-CCA and is comprised of monomorphic tumor cells that exhibit characteristics intermediate between hepatocytes and cholangiocytes, with immunohistochemical expression of hepatocytic and cholangiocytic markers within the same cell. Another rare entity, combined HCC and neuroendocrine carcinoma (NEC), contains an admixture of HCC and NEC components within the same tumor. Undifferentiated primary liver carcinoma, on the other hand, lacks definitive lineage differentiation beyond an epithelial phenotype. These heterogeneous PLCs pose diagnostic challenges owing to their mixed/unusual histologic features and overlapping immunohistochemical markers. They tend to have poor prognoses, highlighting the critical importance of accurate and timely diagnosis.

Significant advancements over the past 2 decades have reshaped our understanding and diagnostic capabilities for hepatocellular carcinoma (HCC). These advancements span molecular insights into key driver gene mutations and chromosomal aberrations, refined recognition of distinct histologic subtypes, improved differentiation from precursor and benign hepatic lesions, and enhanced strategies for interpreting challenging biopsy samples. The discovery of driver mutations such as TERT promoter, CTNNB1 , and TP53 , along with chromosomal alterations, has provided essential tools for identifying malignancy and understanding tumor behavior. Concurrently, the recognition of distinct morphomolecular HCC subtypes has underscored the importance of integrating histologic and molecular findings for accurate diagnosis and prognostic assessment. In addition, differentiating HCC from dysplastic nodule and hepatocellular adenoma remains a diagnostic challenge, often requiring a combination of morphologic, immunohistochemical, and molecular approaches. Moreover, the interpretation of biopsy samples from borderline hepatocellular neoplasms highlights the limitations of conventional pathology alone and the need for comprehensive diagnostic strategies. This review aims to provide an updated overview of these interconnected aspects, emphasizing their collective role in advancing the precision diagnosis of HCC.

There are inherited germline variants that predispose patients to select mesenchymal tumors with associated tumor syndromes. While many of these tumors are clinically suspected or diagnosed early in life, pathologists can play a critical role in their initial recognition and reporting, prompting appropriate confirmatory testing and follow-up for the affected patient and screening for their family members. Hereditary conditions commonly encountered in association with bone and soft tissue pathology include Hereditary Multiple Osteochondromas, Familial Adenomatous Polyposis, Carney Complex, and Neurofibromatosis Type I. Additional syndromes include Rhabdoid Tumor Predisposition Syndrome, Familial Schwannomatosis, DICER1 syndrome, and others. Herein, we describe select bone and soft tissue tumors associated with familial syndromes, aiming to provide a guide for practicing surgical pathologists on how to recognize these lesions and when they should raise the possibility of an associated hereditary condition.

BRCA1-associated protein-1 (BAP1) tumor predisposition syndrome is due to germline mutation of BAP1, a tumor suppressor gene. Patients with this syndrome has an increased susceptibility to the development of uveal melanomas, cutaneous melanomas, cutaneous atypical melanocytic lesions, mesotheliomas, clear cell renal cell carcinoma, and other tumors. These syndromic tumors exhibit an aggressive growth and earlier onset in comparison to sporadic tumors. In this review we outline the history, epidemiology, and genetics of this syndrome. The clinical presentation and histopathology of commonly developed tumors in syndromic patients, namely uveal melanomas, cutaneous atypical melanocytic lesions, mesotheliomas, and clear cell renal cell carcinoma are discussed.

The approach to eosinophilia and mast cell disorders in the bone marrow is diverse and depends on multiple factors including access to ancillary testing, resources to support testing, type of practice setting (eg, community, remote, tertiary care center or specialized referral center for these disorders) and whether there are options for clinical trial enrollment. That said, while there are some basic principles to the workup that we can all likely agree upon, individual practice habits will need to be tailored to suit an individual setting. As such, the approach presented in this manuscript is meant to serve as a practical guide and not as dogma per se. Importantly, an in-depth discussion of individual diseases and International Consensus Classification diagnostic criteria will not be covered, as the main focus of this article is the approach to these disorders. The reader is referred to a comprehensive discussion of these diseases and diagnostic criteria in several excellent articles. While there are clear areas of overlap between eosinophilia and mast cell conditions (eg, systemic mastocytosis associated with eosinophilia, myeloid neoplasm with eosinophilia, and tyrosine kinase rearrangements), it is the authors' opinion that it is perhaps easier to navigate these entities separately (eg, eosinophilia as one broad topic and mast cell conditions as another) and to recognize the settings in which overlap may exist and what testing might be considered. Eosinophilia and mast cell conditions will be discussed separately supplemented by generous use of figures and tables to highlight key points.