Paradoxical Development of Reactive Squamous Atypia and Aggressive, Invasive Squamous Cell Carcinoma Following 5-Fluorouracil for Field Cancerization with Concurrent Immunomodulation.

5-fluorouracil (5FU) is a widely prescribed therapy for field cancerization. However, the emergence of cutaneous squamous cell carcinoma (cSCC) after 5FU treatment is poorly described. We report five patients with eruptive cSCCs of varying severity following 5FU treatment for field cancerization from four university hospitals between March 2019 and May 2021.

Hydroxychloroquine-induced repetitive atypical pustular drug eruptions in the same patient separated by 12 years.

Hydroxychloroquine (HCQ) has been reported to cause pustular drug eruptions such as acute generalized exanthematous pustulosis (AGEP) and putular psoriasis (PP). Clinical differentitation of these entities is often difficult. This case emphasizes characteritics of AGEP and PP as well as the need for clinicans to proactively follow-up these patients to monitor for the more aggressive outcome of PP.

3D reconstruction of skin and spatial mapping of immune cell density, vascular distance and effects of sun exposure and aging.

Mapping the human body at single cell resolution in three dimensions (3D) is important for understanding cellular interactions in context of tissue and organ organization. 2D spatial cell analysis in a single tissue section may be limited by cell numbers and histology. Here we show a workflow for 3D reconstruction of multiplexed sequential tissue sections: MATRICS-A (Multiplexed Image Three-D Reconstruction and Integrated Cell Spatial - Analysis).

Deep Shave Removal of Suspected Basal Cell Carcinoma: A Prospective Study.

Background: Diagnosis and treatment of basal cell carcinoma (BCC) in the same visit by shave removal may decrease health care spending and promote patient satisfaction.

Objective: To prospectively evaluate deep shave removal of lesions clinically suspicious for low-risk BCC on the trunk or extremities in immunocompetent patients.

Materials And Methods: Deep shave removal with the intent to remove the entire tumor was performed from January 2015 to June 2016, and patients were followed prospectively for clinical evidence of tumor recurrence.

Intravascular Lymphoma - The Creepy Crawler: A Case Series and Brief Literature Review.

Background: Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of extranodal B-cell lymphoma, which has traditionally been associated with poor outcomes. Despite increasing recognition, IVLBCL requires a high degree of clinical suspicion on the part of the clinician for its diagnosis.

Case Series: We present four patient cases: A 69-year-old female with constitutional symptoms and cognitive decline; a 78-year-old female with kidney injury and constitutional symptoms whose disease rapidly progressed to multiorgan failure and death; a 70-year-old asymptomatic female with an incidentally found, enlarged thyroid; and a 63-year-old male with cytopenia and constitutional symptoms.

Local IL-23 is required for proliferation and retention of skin-resident memory T17 cells.

The cytokine interleukin-23 (IL-23) is critical for development and maintenance of autoimmune inflammation in nonlymphoid tissues; however, the mechanism through which IL-23 supports tissue-specific immunity remains unclear. In mice, we found that circulating memory T cells were dispensable for anamnestic protection from skin infection, and tissue-resident memory (T) cell-mediated protection from reinfection required IL-23. Administration of anti-IL-23 receptor antibody to mice after resolution of primary infection resulted in loss of CD69 CD103 tissue-resident memory T helper 17 (T) cells from skin, and clinical anti-IL-23 therapy depleted T cells from skin of patients with psoriasis.

Pathology Education Powered by Virtual and Digital Transformation: Now and the Future.

Context.—: Myriad forces are changing teaching and learning strategies throughout all stages and types of pathology education. Pathology educators and learners face the challenge of adapting to and adopting new methods and tools.

Improvement of Unilateral Breast Hypoplasia With Oral Spironolactone in a Patient With Becker Nevus Syndrome.

Becker nevus (BN) is a benign cutaneous smooth muscle hamartoma that presents with a hyperpigmented patch or plaque with or without hypertrichosis.1 BN may be associated with ipsilateral breast hypoplasia or other musculoskeletal abnormalities, an association which has been termed Becker nevus syndrome (BNS).

TGFβ activating integrins β6 and β8 are dysregulated in inflammatory skin disease and cutaneous melanoma.

Background: Integrins avβ6 and avβ8 are expressed by keratinocytes and transactivate latent TGFβ. In a murine model, integrin mediated activation of TGFβ has been shown to be critical in maintaining skin homeostasis, specifically playing roles in epidermal retention of Langerhans cells and resident memory cells T cells (Trm).

Objective: We examine expression of Integrins β6 and β8 in human skin, inflammatory skin disease, benign nevi, and melanoma and hypothesize that integrin expression is dysregulated in disease.

Anatomical structures, cell types and biomarkers of the Human Reference Atlas.

The Human Reference Atlas (HRA) aims to map all of the cells of the human body to advance biomedical research and clinical practice. This Perspective presents collaborative work by members of 16 international consortia on two essential and interlinked parts of the HRA: (1) three-dimensional representations of anatomy that are linked to (2) tables that name and interlink major anatomical structures, cell types, plus biomarkers (ASCT+B). We discuss four examples that demonstrate the practical utility of the HRA.

Cost of Treatment of Benign and Premalignant Lesions During Skin Cancer Screening.

This cross-sectional study examines the costs of skin cancer detection and screening via total body skin examination.

Spindle cell variant of epithelioid cell histiocytoma (spindle cell histiocytoma) with ALK gene fusions: Cases series and review of the literature.

Background: Epithelioid fibrous histiocytoma (EFH) is an uncommon dermal neoplasm expressing anaplastic lymphoma kinase (ALK) protein. Rarely a histopathological variant of this entity exhibits exclusively spindle cells. We report three cases of EFH that do not completely fulfill phenotypic criteria featuring spindle cell morphology and expressing ALK protein.

The molecular landscape and other distinctive features of primary cutaneous follicle center lymphoma.

Primary cutaneous follicle center lymphoma (PCFCL) is distinguished from other follicular lymphomas (FLs) based on its clinicopathologic features including diminished CD10 and frequent lack of BCL2 rearrangements (R). Whether newer germinal center-associated markers would also be less commonly expressed and whether mutational studies would support its segregation from classic FL and FL subsets, including those which also typically lack BCL2R, are uncertain. To address these questions, 22 PCFCLs were stained for myocyte enhancer factor 2B (MEF2B) and human germinal center-associated lymphoma (HGAL), and targeted next-generation sequencing was performed with results compared to a meta-analysis of FL, pediatric-type FL (PTFL), low stage FL (LSFL) and other FL subsets.

Sweet syndrome with pulmonary involvement in a patient with myelodysplastic syndrome.

We report a patient with Sweet syndrome involving the pulmonary system in the context of myelodysplastic syndrome. Although Sweet syndrome may involve a variety of organ systems, the pulmonary system is rarely affected and can result in poor clinical outcomes, including acute respiratory distress syndrome. Both cutaneous and pulmonary symptoms respond well to systemic corticosteroid therapy and early diagnosis and treatment can improve the prognosis.

Melanoma Ex Blue Nevus With GNA11 Mutation and BAP1 Loss: Case Report and Review of the Literature.

Cutaneous melanomas may demonstrate a variety of histopathological features and genetic abnormalities. Melanomas that arise in the setting of blue nevi, also known as "malignant blue nevus" or melanoma ex blue nevus (MBN), share a similar histopathological and mutational profile with uveal melanoma. Most uveal melanomas show characteristic GNA11 or GNAQ mutations; additional BAP1 mutation or loss is associated with the highest risk of metastasis and worst prognosis.