Cutaneous Syncytial Myoepithelioma: An Uncommon and Distinct Variant of Cutaneous Epithelioid Neoplasm

BACKGROUND

Cutaneous syncytial myoepithelioma (CSM) is an uncommon and distinct variant of cutaneous myoepithelioma. We aim to present a case of CSM to enhance the recognition of this unique variant, encompassing its clinical characteristics, histopathological features, immunohistochemical staining, and therapeutic approaches.

CASE PRESENTATION

A 10-year-old girl presented with a dome-shaped nodule located on the skin of her left medial distal arm. Microscopic examination of the skin biopsy revealed a well-defined dermal nodular lesion, surrounded by an epidermal collarette. Tumor cells were composed of epithelioid to spindle-shaped cells with round-to-oval nuclei, small nucleoli, and abundant eosinophilic cytoplasm with a syncytial-like growth pattern. A moderate degree of nuclear pleomorphism was noted. Mitotic activity was not prominent. Immunohistochemical staining revealed positive staining for epithelial membrane antigen, GLUT1, collagen IV, and S100. Smooth muscle actin, CD10, and CD68 showed patchy positivity. CD31, CD34, p63, SOX10, anaplastic lymphoma kinase (ALK), glial fibrillary acidic protein, pankeratin (AE1/AE3/PCK26), Melan-A, and CD1a were negative. Fluorescence in situ hybridization targeting TFE3 and ALK genes was negative. The differential diagnosis included ALK-negative epithelioid cell histiocytoma, epithelioid perineurioma, and CSM. Based on the above findings, a diagnosis of CSM was rendered.

DISCUSSION

CSM is a benign cutaneous neoplasm composed of sheets of histiocytoid or short spindle cells with pale eosinophilic cytoplasm with a syncytial-like growth pattern. Clinically, CSM often presents as a painless, slow-growing nodule or plaque in a broad anatomical distribution with a preference for the distal extremities.. CSM is characteristically positive for epithelial membrane antigen (EMA) and S100 protein and negative for keratins. In challenging cases, molecular testing for EWSR1 gene rearrangement and EWSR1-PBX3 gene fusion aid in confirming the diagnosis.

CONCLUSIONS

The histologic features of CSM present a unique set of challenges posing a diagnostic dilemma, as they can bear resemblance to a range of benign and malignant cutaneous neoplasms including ALK-negative epithelioid cell histiocytoma, epithelioid perineurioma, malignant or nevoid melanoma, and epithelioid sarcoma. An accurate diagnosis is crucial for guiding proper clinical management considering that this entity typically demonstrates an excellent prognosis following a complete surgical excision.

H2A.Z chaperones converge on histone H4 acetylation for melanoma cell proliferation

High levels of H2A.Z promote melanoma cell proliferation and correlate with poor prognosis. However, the role of the two distinct H2A.Z histone chaperone complexes, SRCAP and P400-TIP60, in melanoma remains unclear. Here, we show that individual depletion of SRCAP, P400, and VPS72 (YL1) not only results in loss of H2A.Z deposition into chromatin, but also a striking reduction of H4 acetylation in melanoma cells. This loss of H4 acetylation is found at the promoters of cell cycle genes directly bound by H2A.Z and its chaperones, suggesting a highly coordinated regulation between H2A.Z deposition and H4 acetylation to promote their expression. Knockdown of each of the three subunits downregulates E2F1 and its targets, resulting in a cell cycle arrest akin to H2A.Z depletion. However, unlike H2A.Z deficiency, loss of the shared H2A.Z chaperone subunit YL1 induces apoptosis. Furthermore, YL1 is overexpressed in melanoma tissues, and its upregulation is associated with poor patient outcome. Together, these findings provide a rationale for future targeting of H2A.Z chaperones as an epigenetic strategy for melanoma treatment.

Cutaneous Atypical Fibroxanthoma With Osteoclast-Like Giant Cell: A Rare but Diagnostic Pitfall

BACKGROUND

Atypical fibroxanthoma (AFX) is a dermal-based, low-grade neoplasm with no specific lineage of differentiation. The occurrence of AFX with osteoclast-like giant cells is exceptionally rare. Less than 20 cases have been reported in the literature.

CASE PRESENTATION

A 77-year-old man with a medical history of multiple basal and squamous cell carcinomas of the skin, presented with a progressively growing erythematous nodule on the sun-damaged right central parietal scalp. A shave biopsy showed a dermal spindle cell proliferation accompanied by numerous osteoclast-like multinucleated giant cells and predominant atypical mitotic figures. The immunohistochemical staining showed a diffuse positive staining for CD68 and SMA, patchy staining for CD10, and negative staining for SOX-10, pan-cytokeratin, CK5/6, S100, CD34, and desmin. The tumor was completely excised with negative margins. A subsequent follow-up over a period of 13 months showed no recurrence.

CONCLUSION

Distinguishing AFX with osteoclast-like giant cells from both malignant and benign skin lesions with osteoclast-like giant cells is crucial. Although AFX tumors display worrisome malignant histologic features, most cases have a favorable prognosis with a local recurrence rate below 5% and exceedingly rare metastasis.

HTLV-1 Presenting as an Incidental Finding after a Cosmetic Procedure

A 44-year-old woman presented to a plastic surgeon for liposuction of the abdomen, back, and flanks, a gluteal fat transfer, and a vertical pattern breast lift and small reduction. The patient had a medical history of significantly well-controlled hypertension for 4 years treated with hydrochlorothiazide and amlodipine. She had been pregnant four times and delivered six children with two sets of twins. She was allergic to latex and denied a history of smoking. Her physical examination was unremarkable and her body mass index (BMI) was 26.1. No skin lesions were evident (Figure 1). Her preoperative laboratory findings were within normal limits, with unremarkable electrocardiogram (EKG), chest x-ray, and mammogram. The patient underwent a successful surgical procedure, and the excised breast tissue and skin were sent to pathology for routine evaluation. Surgery removed 220 g of breast tissue from the left breast and 45 g was excised from the right one. The histopathology depicted atypical T-cells in the epidermis and superficial dermis of both left and right breasts. Physical examination failed to evidence lymph-adenopathy or masses. The patient denied weight loss, night sweats, or fever; however, due to her Caribbean heritage, adult T-cell leukemia/ lymphoma was considered and submitted for further histologic workup.

Halogen halos: Report of an early histopathologic finding in iododerma

Iododerma is a rare cutaneous eruption that manifests after exposure to iodine-containing compounds, with few cases reported in the literature. Previous reports of this halogenoderma have described acellular halos simulating cryptococcus on histopathological examination but there is a paucity of reports of biopsies taken early in the disease course. We present a case of a 78-year-old patient who developed a papular eruption after receiving iodinated contrast. A skin biopsy taken within 24 h of the eruption showed a neutrophilic infiltrate with cryptococcal-like acellular haloed structures, indicating that the diagnostic finding may be found early in the disease course.

Complex Autoinflammatory Syndrome Unveils Fundamental Principles of JAK1 Kinase Transcriptional and Biochemical Function

Autoinflammatory disease can result from monogenic errors of immunity. We describe a patient with early-onset multi-organ immune dysregulation resulting from a mosaic, gain-of-function mutation (S703I) in JAK1, encoding a kinase essential for signaling downstream of >25 cytokines. By custom single-cell RNA sequencing, we examine mosaicism with single-cell resolution. We find that JAK1 transcription was predominantly restricted to a single allele across different cells, introducing the concept of a mutational “transcriptotype” that differs from the genotype. Functionally, the mutation increases JAK1 activity and transactivates partnering JAKs, independent of its catalytic domain. S703I JAK1 is not only hypermorphic for cytokine signaling but also neomorphic, as it enables signaling cascades not canonically mediated by JAK1. Given these results, the patient was treated with tofacitinib, a JAK inhibitor, leading to the rapid resolution of clinical disease. These findings offer a platform for personalized medicine with the concurrent discovery of fundamental biological principles.

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Janus kinase (JAK1) mutation underlies monogenic autoinflammatory disease

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S703I mutation enhances downstream signaling by transactivation of partnering JAKs

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Mosaicism and monoallelic expression shape JAK1 transcription patterns

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JAK inhibitor therapy resolves clinical disease

Lichen Myxedematosus: Case Report and Review of Literature

Lichen myxedematosus (LM) is an idiopathic cutaneous mucinosis, commonly described as localized scleromyxedema. In contrast to scleromyxedema, there is typically no systemic involvement. Treatment options are limited and spontaneous resolution has been reported. We present the case of a 66-year-old Hispanic male referred by his primary care physician for evaluation of asymptomatic dark spots on his trunk and extremities present for about one-year. Physical exam revealed smooth, brown hyperpigmented papules coalescing into plaques on the trunk. Multiple well-demarcated oval dark brown plaques measuring 3 cm in size were located on the upper back, peri-umbilical area, bilateral lower extremities, and buttocks. A diagnosis of lichen myxedematosus was made based on histologic features observed in the dermis. There are 5 subtypes of LM: a discrete papular form, acral persistent papular mucinosis, self-healing papular mucinosis, papular mucinosis of infancy, and a pure nodular form. Occasional patients with LM have atypical features or features intermediate between scleromyxedema and localized LM. We present a case of atypical LM with mixed features of the different subtypes. Herein we will review the varied clinical presentations of LM and highlight the distinguishing features of scleromyxedema. J Drugs Dermatol. 2020;19(3): 320-322 doi:10.36849/JDD.2020.4864.

Deep Learning Based on Standard H&E Images of Primary Melanoma Tumors Identifies Patients at Risk for Visceral Recurrence and Death

PURPOSE

Biomarkers for disease-specific survival (DSS) in early-stage melanoma are needed to select patients for adjuvant immunotherapy and accelerate clinical trial design. We present a pathology-based computational method using a deep neural network architecture for DSS prediction.

EXPERIMENTAL DESIGN

The model was trained on 108 patients from four institutions and tested on 104 patients from Yale School of Medicine (YSM, New Haven, CT). A receiver operating characteristic (ROC) curve was generated on the basis of vote aggregation of individual image sequences, an optimized cutoff was selected, and the computational model was tested on a third independent population of 51 patients from Geisinger Health Systems (GHS).

RESULTS

Area under the curve (AUC) in the YSM patients was 0.905 (P < 0.0001). AUC in the GHS patients was 0.880 (P < 0.0001). Using the cutoff selected in the YSM cohort, the computational model predicted DSS in the GHS cohort based on Kaplan-Meier (KM) analysis (P < 0.0001).

CONCLUSIONS

The novel method presented is applicable to digital images, obviating the need for sample shipment and manipulation and representing a practical advance over current genetic and IHC-based methods.

Prediction of distant melanoma recurrence from primary tumor digital H&E images using deep learning

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Background: Patients with resected melanoma are at high risk for systemic recurrence. Quantifying the risk of recurrence can help identify the need for adjuvant immunotherapies, and accelerate the acquisition of survival statistics in clinical trials. Methods: 75 patients with stages I, II, and III melanoma seen at Columbia University Medical Center between 2001 and 2014 and The Icahn School of Medicine at Mount Sinai between 2000 and 2010 were included based on availability of tissue and 24 months of clinical follow-up. Images were scanned into tiff files (Aperio Biosystems). Deep neural net (DNN) architecture was designed consisting of convolutional and recurrent neural networks (CNN, RNN). Using QuPath open source software for nuclear segmentation and cell classification, we generated cell location, density, and clustering features to identify tissue areas for training of network parameters. DNN analyzes image and feature information locally within an H&E image, generating a prediction vote per region, and votes are averaged. Results: The model was validated on two independent external sets of stage I-III primary melanomas. Cohort 1 (Yale Medical Center), had n = 86 patients, of whom 49 were alive or had no evidence of disease at death (no DMR) and 37 died from melanoma. The second set, Cohort 2 (Geisnger Health Systems), had n = 29 patients, 15 without DMR and 14 with DMR. Prediction scores correlated with DMR status in both sets (AUC = 0.94 and 0.77 for Cohorts 1 and 2, respectively). A multivariable Cox proportional hazard model showed DNN recurrence prediction to be an independent prognostic factor for both Cohort 1 (HR = 2.54, 95% CI: 1.54-4.19, p = .0004***) and Cohort 2 (HR = 8.43, 95% CI: 2.58-27.51, p = .001**). Conclusions: We designed a DNN for quantitative prediction of melanoma recurrence from a H&E stained tissue. The prediction score warrants further study in larger patient cohorts and may constitute a novel digital pathology tool for the selection of melanoma patients for adjuvant immunotherapy. [Table: see text]

Erythema elevatum diutinum: a case report and review of literature

Erythema elevatum diutinum (EED) is a rare cutaneous leukocytoclastic vasculitis thought to be related to increased levels of circulating antibodies. It has been shown to be associated with HIV infection, tuberculosis, as well as various autoimmune diseases. A retrospective review of all cases of EED indexed in PubMed between 1990 and 2014 was performed. Inclusion criteria for articles was availability of full text in English and a biopsy-confirmed diagnosis of EED. All other articles were excluded. Cases were stratified by age and anatomic location of the lesions. Treatment response was coded as "complete," "partial," and "none." A total of 133 cases of EED with 381 lesions detailed in case reports and case series were included. Twenty-one cases were associated with HIV. Of 47 patients with reported paraproteinemias, IgA paraproteinemia was found in 57.45%, IgG paraproteinemia in 29.8%, IgM paraproteinemia in 10.6%, and IgD paraproteinemia in 2.1% of cases. Of 40 (30.1%) patients with reported comorbid autoimmune disease, rheumatoid arthritis was associated with 10 cases. Cancer was found to be associated with 9.77% of cases. Seventy-five patients were treated with dapsone, with 36 (48%) achieving complete treatment response, 24 (32%) achieving partial response, and seven (9.3%) achieving no response. Keeping the clinical associations of EED in mind, especially malignancy, is critical in management of the disease. More structured studies need to take place in order to fully define the mechanisms and strength of these associations.

Transcriptional dissection of melanoma identifies a high-risk subtype underlying TP53 family genes and epigenome deregulation

BACKGROUND

Melanoma is a heterogeneous malignancy. We set out to identify the molecular underpinnings of high-risk melanomas, those that are likely to progress rapidly, metastasize, and result in poor outcomes.

METHODS

We examined transcriptome changes from benign states to early-, intermediate-, and late-stage tumors using a set of 78 treatment-naive melanocytic tumors consisting of primary melanomas of the skin and benign melanocytic lesions. We utilized a next-generation sequencing platform that enabled a comprehensive analysis of protein-coding and -noncoding RNA transcripts.

RESULTS

Gene expression changes unequivocally discriminated between benign and malignant states, and a dual epigenetic and immune signature emerged defining this transition. To our knowledge, we discovered previously unrecognized melanoma subtypes. A high-risk primary melanoma subset was distinguished by a 122-epigenetic gene signature ("epigenetic" cluster) and TP53 family gene deregulation (TP53, TP63, and TP73). This subtype associated with poor overall survival and showed enrichment of cell cycle genes. Noncoding repetitive element transcripts (LINEs, SINEs, and ERVs) that can result in immunostimulatory signals recapitulating a state of "viral mimicry" were significantly repressed. The high-risk subtype and its poor predictive characteristics were validated in several independent cohorts. Additionally, primary melanomas distinguished by specific immune signatures ("immune" clusters) were identified.

CONCLUSION

The TP53 family of genes and genes regulating the epigenetic machinery demonstrate strong prognostic and biological relevance during progression of early disease. Gene expression profiling of protein-coding and -noncoding RNA transcripts may be a better predictor for disease course in melanoma. This study outlines the transcriptional interplay of the cancer cell's epigenome with the immune milieu with potential for future therapeutic targeting.

FUNDING

National Institutes of Health (CA154683, CA158557, CA177940, CA087497-13), Tisch Cancer Institute, Melanoma Research Foundation, the Dow Family Charitable Foundation, and the Icahn School of Medicine at Mount Sinai.

Genomic Characterization of Dysplastic Nevi Unveils Implications for Diagnosis of Melanoma

A well-defined risk factor and precursor for cutaneous melanoma is the dysplastic nevus. These benign tumors represent clonal hyperproliferation of melanocytes that are in a senescent-like state, but with occasional malignant transformation events. To portray the mutational repertoire of dysplastic nevi in patients with the dysplastic nevus syndrome and to determine the discriminatory profiles of melanocytic nevi (including dysplastic nevi) from melanoma, we sequenced exomes of melanocytic nevi including dysplastic nevi (n = 19), followed by a targeted gene panel (785 genes) characterization of melanocytic nevi (n = 46) and primary melanomas (n = 42). Exome sequencing revealed that dysplastic nevi harbored a substantially lower mutational load than melanomas (21 protein-changing mutations versus >100). Known "driver" mutations in genes for melanoma, including CDKN2A, TP53, NF1, RAC1, and PTEN, were not found among any melanocytic nevi sequenced. Additionally, melanocytic nevi including dysplastic nevi showed a significantly lower frequency and a different UV-associated mutational signature. These results show that although melanocytic nevi and dysplastic nevi harbor stable genomes with relatively few alterations, progression into melanomas requires additional mutational processes affecting key tumor suppressors. This study identifies molecular parameters that could be useful for diagnostic platforms.

Melanoma arising in a tattoo: case report and review of the literature

Various benign and malignant lesions have been described in relation to tattoos including melanoma. Few cases of malignant melanoma (MM) arising in tattoos have been reported in the literature. We report a 79-year-old man with an MM that arose in a tattoo he had for 60 years on the inferior aspect of the left arm. This case underscores the need for careful examination of tattoos to insure that dysplastic or malignant pigmented lesions are not overlooked. We also discuss the possibility of a pathogenic relationship between MM and tattoos.

Generalized Anetoderma after Intravenous Penicillin Therapy for Secondary Syphilis in an HIV Patient

Anetoderma is a rare, benign disorder characterized microscopically by the pan-dermal loss of elastic fibers in the dermis and presenting clinically as circumscribed, skin-colored or grey-white atrophic macules and/or patches on the trunk and/or extremities. Lesions are described as having a "sac-like" appearance, since they bulge or herniate upon palpation. Although the clinical picture is characteristic, a definitive diagnosis requires histological confirmation in order to differentiate this disorder from other conditions of elastolysis, such as cutis laxa and mid-dermal elastolysis. Little is known concerning the pathogenesis of this condition, and treatment attempts have been both diverse and unsuccessful. This article will review a case of generalized anetoderma in a patient with secondary syphilis after being treated with intravenous penicillin, along with a concise literature review.