Dermatopathology最新文献

{"title":"Scalp Biopsies for Alopecia.","authors":"Tullio Brunetti, Cosimo Misciali, Luca Rapparini, Francesca Bruni, Michela Starace, Michelangelo La Placa","doi":"10.3390/dermatopathology13030044","DOIUrl":"10.3390/dermatopathology13030044","url":null,"abstract":"<p><strong>Background: </strong>Hair loss is one of the most common reasons patients seek dermatologic evaluation. Although clinical examination and trichoscopy establish the diagnosis in most cases, scalp biopsy remains essential when findings are inconclusive, when cicatricial alopecia is suspected, or when histopathologic documentation is required before systemic therapy.</p><p><strong>Methods: </strong>This narrative review synthesizes evidence from PubMed/MEDLINE and Embase on the indications, biopsy site selection, sampling technique, specimen processing, and histopathologic interpretation of scalp biopsy in alopecia.</p><p><strong>Results: </strong>Diagnostic yield depends on appropriate patient selection, trichoscopy-guided site selection, meticulous sampling, and optimal processing. A 4-mm punch oriented parallel to the hair shafts and extending into the subcutaneous fat, combined with horizontal and vertical sectioning (HoVert or Tyler technique), allows the most comprehensive assessment of follicular architecture. Histopathology reliably separates scarring from nonscarring alopecia and, in cicatricial forms, classifies disease by the predominant inflammatory infiltrate following the NAHRS scheme. Ancillary studies, including direct immunofluorescence, periodic acid-Schiff staining, elastic fiber stains, and microbiologic cultures, are applied selectively when clinically indicated.</p><p><strong>Conclusions: </strong>Integrating clinical, trichoscopic, and histopathologic findings improves diagnostic accuracy and guides therapeutic decisions. Close collaboration between the dermatologist and dermatopathologist maximizes the diagnostic value of scalp biopsy.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605222/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Skin Basal Cell Carcinosarcoma in a Trichoblastic Guise-Molecular Characterization of a Novel Entity Mimicking a Pyoderma Gangrenosum.","authors":"Paul Georg, Roland Blum, Robert Hunger, Bastian Dislich, Ronald Wolf","doi":"10.3390/dermatopathology13030045","DOIUrl":"10.3390/dermatopathology13030045","url":null,"abstract":"<p><p>Basal cell carcinosarcomas (BCCSs) are rare, aggressive biphasic epithelial-mesenchymal neoplasms typically occurring in elderly patients. Their nonspecific clinical presentation may mimic inflammatory disorders, necessitating histopathological examination. We characterize a novel cutaneous BCCS with prominent trichoblastic differentiation, clinically mimicking ulcerative pyoderma gangrenosum. Although morphologically resembling trichoblastic carcinosarcoma (TBCS), the tumor retained a BCC-associated genetic signature, supporting a basal cell rather than a primary trichoblastic lineage. We therefore propose the provisional designation \"basal cell carcinosarcoma with divergent trichoblastic differentiation (BCCS-DTB)\", suggesting acquired follicular lineage plasticity within a Hedgehog-driven, UV-mutagenized BCC clone. Shared molecular alterations across epithelial and sarcomatous components support monoclonality and an inside-out epithelial-mesenchymal transition (EMT) model, with progressive acquisition of trichoblastic and sarcomatous features. The patient's young age, unusual tumor location, and development during the COVID-19 pandemic raise the hypothesis of additional environmental influences. Detection of associated spike protein and Snail expression is hypothesis-generating given their reported association with EMT. Further cases are required to validate the molecular profile for diagnostic and therapeutic relevance involving Hedgehog, FGFR2, and mTOR signaling.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605686/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nail Unit Specimens.","authors":"Curtis T Thompson","doi":"10.3390/dermatopathology13030043","DOIUrl":"10.3390/dermatopathology13030043","url":null,"abstract":"<p><p>Histologic submission and processing of nail unit specimens require special attention, primarily because of the contrast between the hard plate and the delicate matrix/bed tissue. Adherence of the plate to the glass slide is particularly challenging, and a protocol is included to address this challenge. Loss of the often small, fragile matrix/bed tissue can lead to absence of histopathologic features needed to make a definitive diagnosis. Of primary importance is the submission of matrix/bed specimens, which are often small and fragmented on a paper template of a nail, which is then placed securely in a tissue cassette between sponges, thereby preserving tissue orientation and allowing for flat fixation for a minimum of 8 h. Immunostains and other special stains also differ somewhat from their use elsewhere on the skin, the details of which are presented.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605043/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Basic Principles of Skin Biopsy Optimization in Dermatopathology.","authors":"Mar Llamas-Velasco, Eduardo Rozas-Muñoz, Angel Fernandez-Flores, Maria-Teresa Fernandez-Figueras","doi":"10.3390/dermatopathology13030042","DOIUrl":"10.3390/dermatopathology13030042","url":null,"abstract":"<p><p>Skin biopsy is one of the most valuable diagnostic procedures in dermatology, particularly when clinical findings alone are insufficient to establish a diagnosis. However, obtaining an accurate histopathological diagnosis depends on multiple steps, and errors at any stage of the biopsy pathway may compromise the final result. This review synthesizes current evidence and available guidelines on best practices for skin biopsy, integrating the practical experience of four internationally recognized dermatopathologists to address areas where evidence is limited or poorly standardized. The review covers biopsy planning, selection of the optimal biopsy site and technique, specimen handling and fixation, grossing and laboratory processing, prevention of technical artifacts, the use of ancillary diagnostic techniques, and clinicopathological correlation, with particular attention to challenging anatomical sites and complex diseases. Diagnostic accuracy depends on obtaining a representative specimen, maintaining high technical standards throughout tissue processing, providing adequate clinical information, and ensuring close communication between the clinician and the dermatopathologist. In selected cases, multidisciplinary review is required to reach a definitive diagnosis. Adherence to these principles can optimize diagnostic yield, reduce avoidable errors, and ultimately improve patient care.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605635/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TRPV4 Regulates Imiquimod (IMQ)-Induced Psoriasis via CaMKKβ/AMPK and Calmodulin/Akt-Mediated Autophagic Signaling Pathways in Juvenile Murine Keratinocytes.","authors":"Qing Xie, Di Bao, Tao Ruan, Kuangzheng Zhu, Dawei Liu, Tiecheng Zhong","doi":"10.3390/dermatopathology13030041","DOIUrl":"10.3390/dermatopathology13030041","url":null,"abstract":"<p><p><b>Background:</b> Psoriasis is a chronic inflammatory skin disease due to genetic susceptibility and multiple environmental factors. Transient receptor potential vanilloid 4 (TRPV4) is a calcium channel extensively expressed throughout the body with multiple functions. However, the role of TRPV4 in imiquimod (IMQ)-induced -psoriasis progression remains unclear although it is ubiquitously expressed in skin tissues and participates in cutaneous mechano- and thermo-sensation. <b>Methods:</b> Both in vivo and in vitro studies were performed in murine skin tissue and isolated cells. TRPV4 expression, autophagy, and Akt/mTOR phosphorylation were assessed by Western blot and reactive oxygen species (ROS) generation was examined by MitoSOX staining. Cytokine levels were measured by ELISA and cell proliferation was determined by CCK staining. The severity of psoriasis was also checked by psoriasis severity index (PSI), scale and thickness scoring and microscopic observations. <b>Results:</b> IMQ-induced psoriasis was remarkably attenuated in TRPV4 knockout mice compared with their wild-type counterparts, accompanied by reduced expression of several inflammatory cytokines. Deletion of TRPV4 diminished ROS production and Akt/mTOR phosphorylation. In vitro experiments showed that IMQ caused a concentration-dependent increase in autophagy, characterized by an initial increasing phase followed by a declining phase in primary keratinocytes. IMQ-induced autophagic activity was enhanced via Calmodulin/Akt pathway suppression while weakened by CaMKKβ/AMPK pathway inhibition. Moreover, blockade of the Calmodulin/Akt pathway significantly reduced IMQ-induced ROS production and psoriasis severity, whereas inhibition of the CaMKKβ/AMPK pathway exacerbated IMQ-induced psoriasis progression through ROS accumulation. <b>Conclusions:</b> Both CaMKKβ/AMPK and Calmodulin/Akt signaling pathways, as downstream components of TRPV4, are involved in IMQ-induced psoriasis: lower IMQ dosage activates AMPK, thereby preventing psoriasis by ROS clearance, whereas higher IMQ dosage activates Calmodulin and exacerbates psoriasis. Our findings reveal the potential values of targeting TRP-related channels in IMQ-induced psoriasis.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605115/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reply to Fernández-Flores, Á. Desmoplakin-Related Arrhythmogenic Cardiomyopathy Carriers and Desmosomal-Type Acantholysis: A Previous Description of the Keratinocyte \"Fingerprint Sign\". Comment on \"Metze et al. Desmosomal-Type Acantholysis-A New Histologic Pattern Related to Mutations of Genes for Desmosomal Proteins. <i>Dermatopathology</i> 2026, <i>13</i>, 17\".","authors":"Dieter Metze, Kira Süßmuth","doi":"10.3390/dermatopathology13030040","DOIUrl":"10.3390/dermatopathology13030040","url":null,"abstract":"<p><p>We are grateful for the commentary by Ángel Fernández-Flores on our concept of \"desmosomal-type acantholysis\", a distinct histologic form of acantholysis associated with mutations in genes encoding desmosomal proteins [...].</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605827/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Desmoplakin-Related Arrhythmogenic Cardiomyopathy Carriers and Desmosomal-Type Acantholysis: A Previous Description of the Keratinocyte \"Fingerprint Sign\". Comment on Metze et al. Desmosomal-Type Acantholysis-A New Histologic Pattern Related to Mutations of Genes for Desmosomal Proteins. <i>Dermatopathology</i> 2026, <i>13</i>, 17.","authors":"Ángel Fernández-Flores","doi":"10.3390/dermatopathology13030039","DOIUrl":"10.3390/dermatopathology13030039","url":null,"abstract":"<p><p>We read with great interest the article by Metze et al [...].</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13605066/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging In Vivo and Ex Vivo Optical Imaging Technologies in Dermatology and Dermatopathology.","authors":"Christoph Müller, Harald Kittler, Mathias Drach","doi":"10.3390/dermatopathology13030038","DOIUrl":"10.3390/dermatopathology13030038","url":null,"abstract":"<p><p>Optical imaging technologies are increasingly reshaping the interface between clinical dermatology and dermatopathology. In vivo reflectance confocal microscopy (IV-RCM), line-field confocal optical coherence tomography (LC-OCT), and ex vivo confocal microscopy (EV-CM) provide tissue-level morphological information without the need for conventional histopathologic processing or with substantially reduced processing times. These technologies have enabled the concept of the \"virtual biopsy\" and are increasingly integrated into diagnostic workflows. However, their clinical value cannot be understood solely through conventional diagnostic performance metrics such as sensitivity and specificity. Rather, their impact depends on how the information they generate is incorporated into sequential diagnostic pathways and clinical decision-making processes. This review summarizes the principles, current applications, diagnostic performance, limitations, and future prospects of IV-RCM, LC-OCT, and EV-CM. We discuss the complementary strengths of these modalities and propose a systems perspective in which imaging technologies are viewed as components of diagnostic ecosystems linking clinical examination, dermatoscopy, pathology, surgery, and computational decision support. Emerging developments in artificial intelligence, multimodal imaging, and digital pathology are likely to further strengthen these connections and expand the role of optical imaging in dermatology and dermatopathology.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13510460/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148832996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cutaneous Pediatric Vasculitis: A Clinico-Histopathological Overview of Common and Novel Entities.","authors":"Anne Welfringer-Morin, Stéphanie Leclerc-Mercier","doi":"10.3390/dermatopathology13030037","DOIUrl":"10.3390/dermatopathology13030037","url":null,"abstract":"<p><p>Vasculitis encompasses a heterogeneous group of diseases characterized by the inflammation of blood vessels. In children, the diagnosis of vasculitis with cutaneous involvement relies on a combination of clinical evaluation, histopathological examination, and, in some cases, genetic investigations. Diagnosing pediatric vasculitis remains particularly challenging due to overlapping clinical manifestations, variable disease courses, and the evolving nature of histological features. Histopathological assessment aims to confirm inflammation of the vessel walls-either readily visible at low magnification or requiring serial sections-and to characterize the inflammatory infiltrate and other key features that aid in classifying the vasculitis subtype. Accurate diagnosis requires ongoing dialog and collaboration among multiple specialists. In this article, we present the clinical and histopathological features of the most common pediatric vasculitides-including IgA vasculitis and polyarteritis nodosa-as well as newly recognized entities such as COVID-19-associated vasculitis and monogenic vasculitides.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13510461/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148832810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cutaneous Squamous Cell Carcinoma Across the Pre-COVID-19, COVID-19 and Post-COVID-19 Eras: Epidemiology, Risk Stratification, Tumour Aggressiveness, and Clinical Outcomes.","authors":"Martin Manole, Iuliu Gabriel Cocuz, Alexandru-Constantin Ioniță, Maria Baldea, Carla-Antonia Peterdeak, Adrian Horațiu Sabău, Maria-Cătălina Popelea, Emőke Andrea Szász, Andreea Raluca Cozac-Szőke, Andreea Cătălina Tinca, Diana Maria Chiorean, Ovidiu Simion Cotoi","doi":"10.3390/dermatopathology13030036","DOIUrl":"10.3390/dermatopathology13030036","url":null,"abstract":"<p><p><b>Background/Objectives</b>: Cutaneous squamous cell carcinoma (cSCC) is the second most common non-melanoma skin cancer (NMSC) and represents the leading cause of NMSC-related deaths. Despite its growing global burden, comprehensive epidemiological and clinicopathological data from Easter Europe remains limited. This study aimed to evaluate the epidemiological, clinical, histopathological, and surgical characteristics of cSCC diagnosed before, during and after the COVID-19 pandemic. <b>Methods</b>: We conducted a retrospective, descriptive observational study including 332 lesions diagnosed between January 2017 and December 2025 at the Clinical Pathology Department of the Mureș Clinical County Hospital. Demographic, epidemiological, topographic, histopathologic, surgical, and volumetric parameters were analyzed. Tumours were stratified into low-, high-, and very-high-risk categories according to the National Comprehensive Cancer Network (NCCN) criteria. <b>Results</b>: The cohort demonstrated a significant male predominance (<i>n</i> = 193 vs. <i>n</i> = 139; <i>p</i> = 0.0355), with females presenting a higher median age (77 vs. 75; <i>p</i> = 0.0489). Lesions were predominantly located in the head and neck region (<i>n</i> = 216; <i>p</i> < 0.0001), which was significantly associated with very-high-risk tumours (<i>p</i> = 0.0051). Low-risk tumours accounted for 62.35% of cases, while high-risk and very-high-risk lesions comprised 19.88% and 17.77%, respectively (<i>p</i> < 0.0001). Ulcerations were strongly associated with very-high-risk tumours (<i>p</i> < 0.0001). Poor differentiation was more frequent outside the head and neck region (<i>p</i> < 0.0001) and varied significantly across the pandemic periods (<i>p</i> = 0.0349). Tumoral and excision volumes were higher in very-high-risk (<i>p</i> = 0.0070; <i>p</i> = 0.0004) and ulcerated tumours (<i>p</i> < 0.001), with a peak in volume during the COVID-19 period (<i>p</i> < 0.0001). A decrease through the years of diagnosis was observed in tumoral volumes (<i>r</i> = -0.2295; <i>p</i> < 0.0001) and patients showed a weak positive correlation with diagnosis year (<i>r</i> = +0.13; <i>p</i> = 0.019). <b>Conclusions</b>: The study provides an epidemiological and clinicopathological characterization of cSCC within one of the largest Romanian cohorts to date. Tumour aggressiveness was primarily driven by histopathological and topographical features rather than demographic factors. While the COVID-19 pandemic did not induce persistent changes in tumour risk profiles or surgical outcomes, it influenced diagnosis timing and tumour burden. These findings highlight the importance of incorporating temporal and emerging systemic factors, such as pandemics, and infectious events, into future epidemiological models to improve preparedness, early detection, future treatment schemes, and risk stratification in cSCC.</p>","PeriodicalId":42885,"journal":{"name":"Dermatopathology","volume":"13 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13511044/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148832911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}