PRAME Immunostaining in BAP-1-Inactivated Melanocytic Tumors: Unraveling Diagnostic Complexity and Exploring Germline Mutation Associations.

Background: Cutaneous melanocytic tumors with BAP-1 inactivation (BIMTs), linked to mutations in the BAP-1 gene, present diagnostic challenges due to their morphological similarities with other melanocytic lesions. The search for reliable diagnostic markers, including PRAME, holds potential to significantly improve the accuracy of differential diagnoses.

Methods: A retrospective analysis of 32 BIMTs from 25 patients, collected between 2018 and 2022, involved histologic examination and immunostaining for BAP-1 and PRAME.

Different Mutational Profiles of Subcutaneous Panniculitis-like T-cell Lymphoma and Lupus Panniculitis: An Additional Case Series.

Background: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cytotoxic T-cell lymphoma with indolent behavior, mostly present in women and associated with immunological diseases whose pathogenic background is still poorly understood. SPTCL is associated with lupus erythematosus panniculitis (LEP) and histologically misdiagnosed.

Objectives: The aim of our study was to identify mutations affecting the pathogenesis of both SPTCL and LEP.

Different Mutational Profiles of Subcutaneous Panniculitis-like T-cell Lymphoma and Lupus Panniculitis: An Additional Case Series.

Background: Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare cytotoxic T-cell lymphoma with indolent behavior, mostly present in women and associated with immunological diseases whose pathogenic background is still poorly understood. SPTCL is associated with lupus erythematosus panniculitis (LEP) and histologically misdiagnosed.

Objectives: The aim of our study was to identify mutations affecting the pathogenesis of both SPTCL and LEP.

Interobserver Variability in the Histopathological Evaluation of Melanoma: Analysis of 60 Cases.

Introduction: Since the field of dermatopathology is not an exact science, it is subject to personal subjectivity, which sometimes causes disagreements on the diagnosis and assessment of some histological features. In the case of melanoma, some variables such as regression are associated with low interobserver agreement. On the contrary, other variables such as the measurement of Breslow thickness show high reproducibility.

Urticarial mycosis fungoides: A distinctive presentation with blood involvement and a peculiar immunophenotype.

Mycosis fungoides (MF) has been widely reported to mimick a considerable number of different dermatoses, including scarring alopecia, bullous dermatoses or cysts, and comedones. In atypical presentations, histopathology is essential for the diagnosis. We present two cases of MF with clinical urticarial lesions and a striking blood involvement that responded to mogamulizumab treatment.

Pharmacokinetics and safety of LEAD-452, an EGFR-specific 4-1BB-agonistic trimerbody in non-human primates.

LEAD-452 is a humanized bispecific EGFR-targeted 4-1BB-agonistic trimerbody with a unique trimeric configuration compared to other 4-1BB-specific antibodies that are currently in development. Indeed, enhanced tumor-specific costimulation and very remarkable safety and efficacy profiles have been observed in mouse models. Here, we conducted for the first time a preclinical pharmacokinetic and toxicity study in non-human primates (NHP) (Macaca fascicularis).

[Main Types of Cysts in Dermatopathology: Part 1].

Cystic structures represent one of the most common findings in dermatopathology. These encompass both cystic tumors and pseudocysts resulting from the accumulation of certain substances, such as mucin. In a two-part series (of which this is the first part), we have reviewed the principal types of cysts and pseudocysts that may be observed in cutaneous biopsies, examining their histopathological features and primary differential diagnoses.

Endoglin, a Novel Biomarker and Therapeutical Target to Prevent Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis.

Purpose: Malignant peripheral nerve sheath tumors (MPNST) are highly aggressive soft-tissue sarcomas that lack effective treatments, underscoring the urgent need to uncover novel mediators of MPNST pathogenesis that may serve as potential therapeutic targets. Tumor angiogenesis is considered a critical event in MPNST transformation and progression. Here, we have investigated whether endoglin (ENG), a TGFβ coreceptor with a crucial role in angiogenesis, could be a novel therapeutic target in MPNSTs.

A PD-L1/EGFR bispecific antibody combines immune checkpoint blockade and direct anti-cancer action for an enhanced anti-tumor response.

Immune checkpoint blockade (ICB) with antibodies has shown durable clinical responses in a wide range of cancer types, but the overall response rate is still limited. Other effective therapeutic modalities to increase the ICB response rates are urgently needed. New bispecific antibody (bsAb) formats combining the ICB effect and a direct action on cancer cells could improve the efficacy of current immunotherapies.

Correlation Between Endoglin and Malignant Phenotype in Human Melanoma Cells: Analysis of hsa-mir-214 and hsa-mir-370 in Cells and Their Extracellular Vesicles.

Endoglin (CD105) is an auxiliary receptor of transforming growth factor (TGF)-β family members that is expressed in human melanomas. It is heterogeneously expressed by primary and metastatic melanoma cells, and endoglin targeting as a therapeutic strategy for melanoma tumors is currently been explored. However, its involvement in tumor development and malignancy is not fully understood.

Clinical, histopathologic, immunohistochemical, and electron microscopic findings in cutaneous monkeypox: A multicenter retrospective case series in Spain.

Background: The worldwide outbreak of monkeypox has evidenced the usefulness of the dermatologic manifestations for its diagnosis.

Objective: To describe the histopathologic and immunohistochemical findings of monkeypox cutaneous lesions.

Methods: This is a retrospective histopathologic and immunohistochemical study of 20 patients with positive Monkeypox virus DNA polymerase chain reaction and immunohistochemical positivity for Vaccinia virus in cutaneous lesions.

Foamy Cell Histiocytosis Is a Diagnostic Pitfall: A Case Report of Xanthomatosis Secondary to Sitosterolemia Mimicking Progressive Nodular Histiocytosis.

We report a noteworthy case of a 10-year-old girl who presented with papular and nodular lesions on the skin that were clinically and histologically mistaken for progressive nodular histiocytosis. During the clinical management of the patient, the high lipid levels raised the suspicion of lipid metabolism disease and helped us to make the correct diagnosis of sitosterolemia. In sitosterolemia, proper management such as restriction of plant sterol intake and administration of cholesterol absorption inhibitor can improve prognosis.