Gregory A. Hosler

Nevi with site‐related atypia: a review of melanocytic nevi with atypical histologic features based on anatomic site

A subset of melanocytic nevi share features with melanoma and nevi with architectural disorder but are biologically inert and to date do not appear to portend an increased risk for the development of malignancy. These benign nevi with certain atypical histologic features cluster among specific anatomic sites and are thus designated nevi with site‐related atypia. We categorize these lesions into four main groups: acral, genital, special site and conjunctival, based on anatomy and relative prevalence of specific atypical histologic features. As the literature and our recognition of these lesions continue to grow, our understanding of their biology has not kept pace.

Clinical Experience with the Cervista HPV HR Assay: Correlation of Cytology and HPV Status from 56,501 Specimens

Testing for high-risk (HR) human papillomavirus (HPV) is a key component of current recommendations for cervical cancer screening. Herein is described our clinical experience using Cervista HPV HR, a testing platform recently approved by the US Food and Drug Administration for clinical use. Using data from a high-volume commercial laboratory, a retrospective analysis of cytologic and Cervista HPV HR test results from 56,501 samples was performed, and an indirect comparison was made with previous experience with 53,008 samples tested using the Hybrid Capture 2 platform. Of samples analyzed using Cervista HPV HR, 1.5% were of insufficient volume for testing and 1.1% yielded an insufficient signal from the internal control to be reported. In samples with a cytological interpretation of atypical squamous cells of undetermined significance, 48.5% (95% confidence interval [CI], 47.5 to 49.5) tested positive using Cervista HPV HR, compared with 59.4% (95% CI, 58.3 to 60.5) of samples using Hybrid Capture 2. Of samples from women aged 30 years or older with a negative cytological interpretation, 5.8% (95% CI, 5.6 to 6.1) tested positive using Cervista HPV HR, compared with 5.5% (95% CI, 5.3 to 5.7) of samples using Hybrid Capture 2. When stratified by five-year age groups between 30 and 65 years, positivity rates for high-risk human papillomavirus were similar in the Cervista HPV HR and Hybrid Capture 2 populations, and were consistent with expectations established by the literature.

Keratosis Follicularis Spinulosa Decalvans Associated with Acne Keloidalis Nuchae and Tufted Hair Folliculitis

Keratosis follicularis spinulosa decalvans is a rare, X-linked disorder characterized by scarring alopecia of the scalp and eyebrows in the setting of widespread keratosis pilaris. Less frequent associations are ocular abnormalities and palmoplantar keratoderma. Acne keloidalis nuchae has previously been described in one patient with keratosis follicularis spinulosa decalvans. We report another case of keratosis follicularis spinulosa decalvans with acne keloidalis nuchae and tufted hair folliculitis, thus further establishing this association.

Differential expression of BAFF and its receptors in discoid lupus erythematosus patients

BACKGROUND B-cell activating factor of the TNF family (BAFF) promotes the maturation and survival of B cells. Because BAFF levels are elevated in systemic lupus erythematosus (SLE) patients, BAFF has been the target of emerging therapies for SLE, such as belimumab. Levels of BAFF and its receptors in discoid lupus erythematosus (DLE) patients are unknown. OBJECTIVE To compare skin and blood mRNA and protein levels of BAFF and its receptors BAFF-R, TACI, and BCMA in DLE subjects with (DLE+/SLE+ (N=28)) and without SLE (DLE+/SLE- (N=35)), psoriasis subjects (N=11), and normal subjects (N=42). METHODS We used quantitative real-time PCR to measure blood and skin BAFF, BAFF-R, TACI, and BCMA mRNA, sandwich ELISAs to measure sera BAFF, and immunohistochemistry to evaluate BAFF and BAFF-R skin protein expression. RESULTS BAFF mRNA and protein levels were highest in DLE+/SLE+blood, followed by DLE+/SLE-, psoriasis, and normal blood. BAFF protein also correlated with anti-nuclear antibodies, and autoantibodies against double-stranded DNA, single-stranded DNA, and ribonucleoprotein, and Systemic Lupus Erythematosus Disease Activity Index scores in DLE patients. While showing no difference between DLE+/SLE+ and DLE+/SLE- skin, BAFF and its receptors mRNA were up-regulated in DLE skin vs. normal and psoriasis skin. DLE skin had higher percentages of BAFF-R⁺ inflammatory cells, likely T cells and macrophages, than psoriasis and normal skin. CONCLUSIONS BAFF may be a serologic marker of systemic disease in DLE patients. BAFF and its receptors are elevated in DLE skin, suggesting that targeted therapies against these proteins could treat refractory DLE patients.

Human polyomavirus 6 and 7 are associated with pruritic and dyskeratotic dermatoses

Background: Human polyomavirus (HPyV)6 and HPyV7 are shed chronically from human skin. HPyV7, but not HPyV6, has been linked to a pruritic skin eruption of immunosuppression. Objective: We determined whether biopsy specimens showing a characteristic pattern of dyskeratosis and parakeratosis might be associated with polyomavirus infection. Methods: We screened biopsy specimens showing “peacock plumage” histology by polymerase chain reaction for HPyVs. Cases positive for HPyV6 or HPyV7 were then analyzed by immunohistochemistry, electron microscopy, immunofluorescence, quantitative polymerase chain reaction, and complete sequencing, including unbiased, next‐generation sequencing. Results: We identified 3 additional cases of HPyV6 or HPyV7 skin infections. Expression of T antigen and viral capsid was abundant in lesional skin. Dual immunofluorescence staining experiments confirmed that HPyV7 primarily infects keratinocytes. High viral loads in lesional skin compared with normal‐appearing skin and the identification of intact virions by both electron microscopy and next‐generation sequencing support a role for active viral infections in these skin diseases. Limitation: This was a small case series of archived materials. Conclusion: We have found that HPyV6 and HPyV7 are associated with rare, pruritic skin eruptions with a distinctive histologic pattern and describe this entity as “HPyV6‐ and HPyV7‐associated pruritic and dyskeratotic dermatoses.”

A subset of CD163+ macrophages displays mixed polarizations in discoid lupus skin

IntroductionLesional skin of patients with discoid lupus erythematosus (DLE) contains macrophages, whose polarization has yet to be investigated. To test our hypothesis that M1 macrophages would be increased in DLE skin, we examined transcriptome alterations in immune cell gene expression and macrophage features in DLE and normal skin by using gene expression and histochemical approaches.MethodsGene expression of RNA from DLE lesional and normal control skin was compared by microarrays and quantitative real-time polymerase chain reaction (RT-PCR). Both skin groups were analyzed for CD163 expression by immunohistochemistry. Double immunofluorescence studies were performed to characterize protein expression of CD163+ macrophages.ResultsDLE skin had twice as many upregulated genes than downregulated genes compared with normal skin. Gene set enrichment analysis comparing differentially expressed genes in DLE and normal skin with previously published gene sets associated with M1 and M2 macrophages showed strong overlap between upregulated genes in DLE skin and M1 macrophages. Quantitative RT-PCR showed that several M1 macrophage-associated genes—e.g., chemokine (C-X-C motif) ligand 10 (CXCL10), chemokine (C-C motif) ligand 5 (CCL5), and signal transducer and activator of transcription 1 (STAT1)—had amplified mRNA levels in DLE skin. CD163+ macrophages were increased near the epidermal-dermal junction and perivascular areas in DLE skin compared with normal skin. However, double immunofluorescence studies of CD163+ macrophages revealed minor co-expression of M1 (CXCL10, tumor necrosis factor-alpha, and CD127) and M2 (CD209 and transforming growth factor-beta) macrophage-related proteins in DLE skin.ConclusionWhereas a subset of CD163+ macrophages displays mixed polarizations in DLE skin, other immune cells such as T cells can contribute to the expression of these macrophage-related genes.

A primary melanoma and its asynchronous metastasis highlight the role of BRAF, CDKN2A, and TERT

Alterations in pathways including BRAF, CDKN2A, and TERT contribute to the development of melanoma, but the sequence in which the genetic alterations occur and their prognostic significance remains unclear. To clarify the role of these pathways, we analyzed a primary melanoma and its metastasis.

Congenital Infantile Fibrosarcoma mimicking a cutaneous vascular lesion: A Case Report and Review of the Literature

Congenital infantile fibrosarcoma (CIFS) is a rare neoplasm of infancy that occurs most frequently in the extremities, and when presenting in the skin, may sometimes resemble infantile hemangiomas or other vascular lesions. Clinically, these tumors differ from hemangiomas in the time of onset, morphology, and growth pattern and must be evaluated histologically for definitive diagnosis. We describe an infant with a neoplasm involving the distal left forearm initially presumed to be a vascular lesion after evaluation by two separate ultrasound studies. He presented at seven weeks of life with a multinodular lesion that had enlarged significantly since birth, and the skin biopsy revealed a fibrosarcoma. This case highlights an unusual cutaneous presentation of CIFS, which varies in appearance from the previous 12 cases reported in the literature. We review the clinical manifestations of these congenital masses and emphasize early diagnosis for conservative therapy and improved prognosis.

Differential glucose requirement in skin homeostasis and injury identifies a therapeutic target for psoriasis

Proliferating cells, compared with quiescent cells, are more dependent on glucose for their growth. Although glucose transport in keratinocytes is mediated largely by the Glut1 facilitative transporter, we found that keratinocyte-specific ablation of Glut1 did not compromise mouse skin development and homeostasis. Ex vivo metabolic profiling revealed altered sphingolipid, hexose, amino acid, and nucleotide metabolism in Glut1-deficient keratinocytes, thus suggesting metabolic adaptation. However, cultured Glut1-deficient keratinocytes displayed metabolic and oxidative stress and impaired proliferation. Similarly, Glut1 deficiency impaired in vivo keratinocyte proliferation and migration within wounded or UV-damaged mouse skin. Notably, both genetic and pharmacological Glut1 inactivation decreased hyperplasia in mouse models of psoriasis-like disease. Topical application of a Glut1 inhibitor also decreased inflammation in these models. Glut1 inhibition decreased the expression of pathology-associated genes in human psoriatic skin organoids. Thus, Glut1 is selectively required for injury- and inflammation-associated keratinocyte proliferation, and its inhibition offers a novel treatment strategy for psoriasis.Keratinocytes require glucose for injury- or inflammation-driven but not homeostatic proliferation, and glucose-transport blockade blocks psoriasis-like pathology in experimental models.

Appropriate use criteria in dermatopathology: Initial recommendations from the American Society of Dermatopathology

Appropriate use criteria (AUC) provide physicians guidance in test selection, and can affect health care delivery, reimbursement policy and physician decision‐making.