Advances In Anatomic Pathology最新文献

Over the past few years, several fusion genes have been reported in dermal-based tumors, resulting in the activation of the microphthalmia (MITF) signalling pathway and a melanocytic phenotype by immunohistochemistry. The best-studied example of these tumors is clear cell sarcoma, which rarely may present as a primary dermal tumor. These tumors are characterized by EWSR1 gene rearrangements, typically with ATF1 and less commonly CREB1. More recently reported cutaneous tumors show gene fusions involving CRTC1::TRIM11, ACTIN::MITF, MITF::CREM, and MED15::ATF1. While the entities in this tumor group share many features, they show subtle distinguishing features, including clinical presentation, histopathologic features, immunophenotype, and outcome. The following overview provides a detailed discussion of these rare tumors with emphasis on differentiating features and differential diagnosis.

The International Consensus Classification (ICC) of myeloid and lymphoid neoplasms follows the precedent set in the Revised European-American lymphoma classification for modern lymphoma classifications by defining specific diseases on the basis of all the available morphologic, immunophenotypic, genetic, and clinical findings. Primary cutaneous lymphomas exhibit a broad range of clinical behavior ranging from lesions which spontaneously regress to those which run an aggressive, often fatal course. Accurate separation of entities is therefore essential for prognostication and to ensure appropriate treatment is administered. However, despite marked differences in clinical course, many subtypes of primary cutaneous lymphoma exhibit remarkably similar, often overlapping, and sometimes indistinguishable pathologic features. While molecular analysis has furthered our understanding of some of these disease entities, it does not yet facilitate robust distinction. Thus, clinical correlation retains a central role in both the diagnosis and classification of primary cutaneous lymphoma. This review aims to draw attention to problem areas in differential diagnosis and hopefully offer some practical suggestions for resolving difficult cases. It will also highlight recent advances in the field and discuss how they reinforce the current classification system and how they might impact of future classifications and treatment strategies.

Follicular lymphoma (FL) is a mature B cell neoplasm classically characterized by B cells harboring the t(14;18) IGH::BCL2 leading to the overexpression of BCL2 in most cases. Conventional FL occurs in lymph nodes and typically shows a follicular B-cell proliferation expressing at least one germinal center marker. Two early lesions closely related to conventional FL are recognized as variants, namely in situ follicular neoplasia (ISFN), and duodenal-type follicular lymphoma (DTFL). FL lacking BCL2 rearrangement ( BCL2 -R negative) accounts for around 10% to 15% of FLs and constitutes a heterogeneous group of FLs. Most of these alternative forms of FL are considered as distinct entities separate from conventional FL in the 2022 International Consensus Classification. This review aims to summarize the key pathologic and diagnostic features of FL conventional and its alternative forms as well as further emphasize the increasing role of molecular studies in the diagnostic work-up.

Aggressive B-cell lymphomas are a biologically and clinically very heterogeneous group of tumors that may be related to different stages of B-cell differentiation development. This review aims to summarize recent advances in the understanding of these tumors with a focus on the practical approach to the diagnosis of these entities. We analyze the defining characteristics of the different subtypes of aggressive B-cell lymphomas, including nodal and extranodal diffuse large B-cell lymphoma, virus-associated lymphomas, terminally differentiated B-cell lymphomas, high-grade B-cell lymphomas, and Burkitt lymphoma. This review particularly explores the integration of morphologic, immunophenotypic, and genetic data that refine diagnostic accuracy and prognostic stratification, underscoring the necessity for a standardized approach in clinical practice. By synthesizing current knowledge, this review aims to enhance the understanding of aggressive B-cell lymphomas within the context of the evolving classification system, paving the way for future research and clinical advancements.

In recent decades, there have been many meaningful contributions to the pathology literature with respect to T-cell lymphoma pathogenesis and biology and improved diagnostics. We know more about disease classification, clinical characteristics, immunophenotype, and genetics than ever before, and yet diagnosis of nodal T-cell lymphomas continues to be a challenging exercise. Complicating interpretation are the many non-neoplastic mimickers of peripheral T-cell lymphoma including drug effects, viruses, autoimmune, and idiopathic conditions, that must be considered when faced with an abnormal lymph node biopsy. The number of immunohistochemical stains required to make a diagnosis of T-cell lymphoma is not standardized and may be exhaustive, requiring judicious use of tissue sections. Clonality studies may contribute to the diagnosis, though questions remain about test modality, when to exercise interpretive caution, and what to do if a clone cannot be demonstrated. Use of next generation sequencing in the diagnosis of nodal T-cell lymphomas is increasing, but how the data can be practically applied to diagnosis is still under examination. The goal of this paper is to consider nodal T-cell lymphoma diagnosis and classification in a modern context, using a question-and-answer format to capture the interest of the reader and address common pathology consultation queries.

This review focuses on the purported applications of multimodal Gen-AI models for anatomic pathology image analysis and interpretation to predict future directions. A scoping review was conducted to explore the applications of multimodal Gen-AI models in advancing histopathology image analysis. A comprehensive search was conducted using electronic databases for relevant articles published within the past year (July 1, 2023 to June 30, 2024). The selected articles were critically analyzed to identify and summarize the applications of multimodal Gen-AI in anatomic pathology image analysis. Multimodal Gen AI models reported in the literature claim moderate to high accuracy on tasks including image classification, segmentation, and text-to-image retrieval. This review demonstrates the potential of multimodal Gen AI models for useful applications in pathology, including assisting with diagnoses, generating data for education and research, and detection of molecular features from anatomic pathology images. These models use data from a few academic institutions thus they require validation on diverse real-world data. There is an urgent need to build consensus models for optimal model performance through multicenter collaboration using a federated learning approach and the use of carefully curated synthetic anatomic pathology data. These models also need to achieve reliability, generalizability and meet the standards required for clinical use. Despite the rigorous need for evaluation and the need to address genuine concerns, multimodal GenAI models present a promising perspective for the advancement and scalability of anatomic pathology.

Bone matrix-forming tumors are a group of neoplasms that exhibit differentiation toward any stage of osteoblast development. Their clinicopathologic features can resemble one another, yet their clinical management may vary significantly. Therefore, appropriate treatment requires accurate diagnosis, which can be challenging, especially with limited biopsy specimens. Recently, the driver genetic alterations underlying these neoplasms have been discovered, and their protein products can be targeted for diagnosis and therapy. Herein, we summarize the recent advances in our understanding of bone matrix-forming tumors and emphasize the integration of molecular genetics into their conventional clinicopathologic evaluation.

Cartilage-forming tumors are a broad and diverse group of neoplasms frequently affecting the skeleton. Distinguishing between the members of this group is important because of significant differences in treatment and prognosis. Accurate diagnosis can be challenging because of similarities in their clinical, radiographic, and pathologic features. Immunohistochemistry and molecular tools are helpful in select instances. Therefore, careful evaluation and correlation of these features are essential in arriving at the correct diagnosis and appropriate patient management. This review provides an overview of the current literature, emphasizing helpful features in diagnosis.

Mesenchymal neoplasms of the gastrointestinal tract are rare compared with epithelial lesions. However, over the past few decades, the increasing volume of gastrointestinal endoscopy has expedited the recognition of several novel entities with varying clinical significance. Its spectrum extends from reactive changes and benign neoplasms to highly aggressive sarcomas. At the malignant end of the spectrum, the importance of correctly diagnosing these tumors is underscored by the specific therapeutic implications available for some tumor types (eg, tyrosine kinase inhibitors for gastrointestinal stromal tumors) that allow personalized treatments. Benign lesions frequently surface among routine polypectomy specimens, sometimes offering diagnostic challenges. However, precise classification is the only way to avoid prognostic uncertainty and overtreatment, and to recognize possible syndromic associations. Hereby, we offer a pragmatic review of the topic from the gastrointestinal pathologist's perspective, who, although more accustomed to epithelial neoplasms, can use an algorithmic approach to diagnose mesenchymal entities successfully.