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). We demonstrate MATRICS-A in 26 serial sections of fixed skin (stained with 18 biomarkers) from 12 donors aged between 32-72 years. Comparing the 3D reconstructed cellular data with the 2D data, we show significantly shorter distances between immune cells and vascular endothelial cells (56 µm in 3D vs 108 µm in 2D). We also show 10-70% more T cells (total) within 30 µm of a neighboring T helper cell in 3D vs 2D. Distances of p53, DDB2 and Ki67 positive cells to the skin surface were consistent across all ages/sun exposure and largely localized to the lower stratum basale layer of the epidermis. MATRICS-A provides a framework for analysis of 3D spatial cell relationships in healthy and aging organs and could be further extended to diseased organs.

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. RESULTS: Seventy-seven lesions were removed from 51 patients, including 29 (37%) superficial and nodular BCCs, 27 (35%) superficial BCCs, 16 (21%) nodular BCCs, and 5 (6%) non-BCCs. Fifteen BCCs (21%) had positive residual margins after deep shave removal, which was significantly more likely to occur in nodular compared with superficial BCCs (odds ratio = 7.8, 95% confidence interval = 1.4-43), and underwent re-excision. Fourteen specimens initially reported to have negative margins after deep shave underwent resectioning, which revealed positive margins in 4 specimens (28.6%). No BCCs have recurred clinically after an average follow-up of 50 months (SE 3.2). CONCLUSION: Consider deep shave removal for low-risk BCCs on the trunk or extremities in immunocompetent patients hoping to avoid a second treatment visit.

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. Retrospective chart analysis was performed on these four patients diagnosed with IVLBCL at our Institute to identify the pathognomonic features of the disease and compare these to the published evidence. IVLBCL has a heterogeneous presentation, as seen in our four patients. The disease is characterized by the exclusive presence of malignant cells inside the blood vessels and lack of organ infiltration. Traditional preliminary diagnostic modalities such as imaging are usually inconclusive, given the paucity of lymphomatous aggregates. A bone marrow biopsy, random skin biopsies, or a focal organ biopsy in appropriate cases is required for diagnosis. Immunosuppression might play a role in the pathogenesis. Timely initiation of aggressive cancer-directed therapy was associated with improved outcomes. Monitoring for disease response and relapse continues to be a challenge. CONCLUSION: Our mini-series highlights the significance of timely diagnosis and intervention in IVLBCL and emphasizes the importance of further research to determine its association with immunosuppression.

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. The digital pathology transformation and the associated educational ecosystem are major factors in this setting of change. OBJECTIVE.­: To identify and collect resources, tools, and examples of educational innovations involving digital pathology that are valuable to pathology learners and teachers at each phase of professional development. DATA SOURCES.­: Sources were a literature review and the personal experience of authors and educators. CONCLUSIONS.­: High-quality digital pathology tools and resources have permeated all the major niches within anatomic pathology and are increasingly well applied to clinical pathology for learners at all levels. Coupled with other virtual tools, the training landscape in pathology is highly enriched and much more accessible than in the past. Digital pathology is well suited to the demands of peer-to-peer education, such as in the introduction of new testing, grading, or other standardized practices. We found that digital pathology was well adapted to apply our current understanding of optimal teaching strategies and was effective at the undergraduate, graduate, postgraduate, and peer-to-peer levels. We curated and tabulated many existing resources within some segments of pathology. We identified several best practices for each training or educational stage based on current materials and proposed high-priority areas for potential future development.

Local IL-23 is required for proliferation and retention of skin-resident memory TH17 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 Candida albicans skin infection, and tissue-resident memory (TRM) cell-mediated protection from C. albicans reinfection required IL-23. Administration of anti-IL-23 receptor antibody to mice after resolution of primary C. albicans infection resulted in loss of CD69+ CD103+ tissue-resident memory T helper 17 (TRM17) cells from skin, and clinical anti-IL-23 therapy depleted TRM17 cells from skin of patients with psoriasis. IL-23 receptor blockade impaired TRM17 cell proliferation but did not affect apoptosis susceptibility or tissue egress. IL-23 produced by CD301b+ myeloid cells was required for TRM17 maintenance in skin after C. albicans infection, and CD301b+ cells were necessary for TRM17 expansion during the development of imiquimod dermatitis. This study demonstrates that locally produced IL-23 promotes in situ proliferation of cutaneous TRM17 cells to support their longevity and function and provides mechanistic insight into the durable efficacy of IL-23 blockade in the treatment of psoriasis.

Random Skin Biopsy Is a Useful Procedure in the Evaluation of Hemophagocytic Lymphohistiocytosis: A Case Report and Review of Literature.

ABSTRACT: Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening syndrome, characterized by aberrant activation of T lymphocytes and macrophages leading to hypercytokinemia. HLH can be familial or a result of various secondary etiologies. We present a case of a 46-year-old woman with a past medical history of multiple sclerosis on rituximab who presented as a transfer from an outside hospital with numerous clinical abnormalities including recurrent episodes of fever of unknown origin for 3 weeks, persistent leukocytosis, hypertriglyceridemia, and steatohepatitis. Given the uncertain nature of her illness, she underwent a random skin biopsy from the abdominal region to exclude hematolymphoid malignancy. Histopathology revealed a brisk histiocytic rich dermal infiltrate accompanied by perivascular lymphocytic infiltrate. The histiocytes were enlarged and positive for muraminadase and CD68 stains exhibiting hemophagocytosis focally. As per the HLH-2004 protocol, our patient met the diagnostic criteria of HLH. Concurrent bone marrow biopsy revealed similar rare hemophagocytosis. Cytogenetics and molecular studies were negative, supporting secondary HLH.

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).

TGFß activating integrins ß6 and ß8 are dysregulated in inflammatory skin disease and cutaneous melanoma.

BACKGROUND: Integrins avß6 and avß8 are expressed by keratinocytes and transactivate latent TGFß. In a murine model, integrin mediated activation of TGFß 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 ß6 and ß8 in human skin, inflammatory skin disease, benign nevi, and melanoma and hypothesize that integrin expression is dysregulated in disease. METHODS: Using immunohistochemistry, we stained tissue from normal human skin (n = 8), psoriasis (n = 6), atopic dermatitis (n = 6), lichen planus (n = 5), benign nevi (n = 24), and melanoma (n = 25) with anti-integrin ß6 and anti-integrin ß8 to survey expression pattern. We also performed a retrospective chart review in the melanoma cohort to examine if integrin ß6 and ß8 expression was associated with increased Breslow depth and worse prognostic staging. RESULTS: Here, we show that human keratinocytes express integrins ß6 and ß8, similar to murine keratinocytes. We also found that inflammatory skin conditions have increased Integrin ß6, but not Integrin ß8 expression. Furthermore, we identified that melanomas have greatly increased expression of integrin ß8 compared to nevi. Additionally, high expression of integrin ß8 was correlated with greater Breslow depth at diagnosis and with worse prognostic staging. CONCLUSION: These findings demonstrate that like murine keratinocytes, human keratinocytes express integrin ß6 and ß8 under steady state conditions. Moreover, altered integrin expression may participate in the development or maintenance of cutaneous inflammation as well as tumor immune evasion.

Basaloid Follicular Hamartoma: An Additional Criterion of Nevoid Basal Cell Carcinoma Syndrome.

ABSTRACT: Basaloid follicular hamartoma (BFH) is a rare, benign follicular neoplasm which typically presents as brown to skin-colored papules on the face, scalp, and trunk. Histologically, BFH consists of cords and strands of basaloid cells forming cystic structures with scant stroma and should be distinguished from infundibulocystic basal cell carcinoma to avoid overly aggressive treatment. Although BFH has been found to be associated with distinct syndromes, including alopecia, myasthenia gravis, and cystic fibrosis, there is often clinical, histopathologic, and genetic overlap with nevoid basal cell carcinoma syndrome (NBCCS). In this article, we describe a case of a 13-year-old patient with NBCCS who presented with multiple BFHs and propose that it its inclusion into the diagnostic criteria for NBCCS be considered.

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.

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. We also analyze the fusion partner genes rearranged with ALK in these cases. METHODS: ALK expression and rearrangement status were evaluated by immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), and next generation sequencing based gene fusion analysis. RESULTS: Three cases, all from females between 25 and 55 years old, have been biopsied from back, left arm, and thumb. All three cases showed tumor with exclusively spindle cell morphology without any epithelioid cells. The tumor cells exhibited strong ALK expression by IHC and FISH study confirmed ALK gene rearrangement in all three cases. DCTN1-ALK fusion was identified in two cases. CONCLUSION: EFH is not always purely epithelioid and its spindled cell variant, spindle cell histiocytoma, should be included in the differential diagnosis of superficial dermal spindled cell neoplasms. ALK immunostain is a useful diagnostic marker for this entity and further studies may be useful to investigate whether DCTN1-ALK fusion mutations are specific to EFH with spindled cell features.

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. Selected fluorescence in situ hybridization studies were also performed. Although 27% of cases lacked CD10, all tested were MEF2B+ and HGAL+. The most common somatic mutations in the 12 to 19 analyzable PCFCL were TNFRSF14 (40%, plus 10% with 1p36 deletions), followed by CREBBP, TNFAIP3, KMT2D, SOCS1, EP300, STAT6, and FOXO1 (17-25%). Three of the most commonly mutated genes in FL (KMT2D, CREBBP, and BCL2) were significantly less commonly mutated in PCFCL than in FL, and TNFAIP was more commonly mutated with no difference for TNFRSF14 between PCFCL and FL or PTFL. CREBBP was also less frequently mutated than in LSFL but more frequently mutated than in PTFL. MAP2K1 mutations were much more common in PTFL (44% versus 0%). Two of 22 of the PCFCL had a BCL2 rearrangement and zero of 12 had a BCL6 rearrangement. These findings, while showing well-recognized and new shared features between PCFCL and other FL, highlight a distinctive mutational profile further supporting its recognition as a distinct entity.