MicroRNA Expression Profiling of Cutaneous Squamous Cell Carcinomas Arising in Different Sites.

OBJECTIVE: To examine the microRNA (miRNA) expression profile of cutaneous squamous cell carcinoma (cSCC) tumors from aggressive head and neck locations compared with nonaggressive anatomic sites and normal controls. STUDY DESIGN: Retrospective analysis of miRNA expression. SETTING: Tertiary care center. SUBJECTS AND METHODS: Tissue samples were collected from 3 anatomic regions: aggressive head and neck sites (ie, ears/lip), nonaggressive locations (ie, extremities/trunk), and adjacent normal skin. RNA was isolated from tissue cores of 45 samples (18 aggressive sites, 15 nonaggressive sites, and 12 normal-adjacent skin). miRNA expression analysis was completed for approximately 800 miRNAs using the NanoString nCounter panel. Five candidate miRNAs were selected for validation. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed on the original samples plus 30 additional tissue samples (7 aggressive sites, 14 nonaggressive sites, and 9 normal-adjacent skin). RESULTS: Five candidate miRNAs with significant differences in miRNA expression (P < 0 ≤ .001) from discovery samples were selected: miR-21, miR-31, let-7g, miR-93, and miR-22. Relative expression for these miRNAs using qRT-PCR in the new sample set did not reveal any significant differences using 1-way analysis of variance. When sets were combined, miR-21 showed increased expression in aggressive tumors relative to nonaggressive tumors (P = .009), but no others reached statistical significance. CONCLUSION: cSCC behaves more aggressively when originating from specific anatomical subsites of the head and neck. Of 5 miRNAs evaluated, only miR-21 showed significantly higher expression in tumors from aggressive sites relative to nonaggressive sites. Larger sample sizes are needed to evaluate other miRNAs.

Expanding the differential of superficial tumors with round-cell morphology: Report of three cases of CIC-rearranged sarcoma, a potentially under-recognized entity.

Among sarcomas with a round-cell morphology that lack rearrangement of the EWSR1 gene, rearrangements involving the CIC gene are the most common. In comparison with Ewing Sarcoma, CIC-rearranged sarcomas present at an older average age, arise almost exclusively in soft tissues, are clinically more aggressive, and are more likely to be resistant to the chemotherapy regimens used for Ewing sarcoma. CIC-rearranged sarcomas present more commonly in a deep location, and we suspect that superficial presentations may be under-recognized. In this case series, we report three of such cases. Overall, the morphology is similar to CIC-rearranged sarcomas of deeper locations. We hope to raise awareness among the dermatopathology community by expanding the differential of superficial tumors with round cell morphology.

Unusual presentation of erythema elevatum diutinum with underlying hepatitis B infection.

Erythema elevatum diutinum (EED) is a rare, chronic, cutaneous small vessel vasculitis of unclear pathogenesis. Classically, lesions present as symmetric red to purple plaques, papules, and nodules overlying joints. First-line therapy is dapsone. We present a case of EED with widespread lesions involving the hands, extensor arms and legs, and trunk. Multiple biopsies showed concentric intradermal perivascular inflammation with dermal fibrosis and leukocytoclastic vasculitis (LCV) suggesting EED in various stages of evolution. An extensive workup was positive for underlying hepatitis B infection. Our case represents the clinicopathologic spectrum that EED can present and emphasizes the importance of searching for an underlying etiology.

Polypoid amelanotic melanoma: a diagnostic challenge.

Melanoma is a highly aggressive cutaneous malignancy with considerable risk for metastasis. These malignant tumors are typically pigmented given that they arise from melanocytes capable of producing melanin. Amelanotic melanomas are a rare variant and there is often a delay in diagnosis owing to lack of pigmentation. Although there are various presentations of amelanotic melanoma, a solitary polypoid nodule is unusual and warrants further reporting. Herein, we present a patient with a 3-year history of a tender firm, skin-to-pink colored polypoid nodule. Excisional biopsy and work up showed an aggressive amelanotic melanoma with depth of 20mm and nodal metastasis consistent with stage IIIC disease. This case highlights the necessity of recognition and prompt management of this rare subtype of melanoma.

Classification of Indeterminate Melanocytic Lesions by MicroRNA Profiling.

PURPOSE: Identification of indeterminate melanocytic skin lesions capable of neoplastic progression is suboptimal and may potentially result in unnecessary morbidity from surgery. MicroRNAs (miRs) may be useful in classifying indeterminate Spitz tumors as having high or low risk for malignant behavior. METHODS: RNA was extracted from paraffin-embedded tissues of benign nevi, benign Spitz tumors, indeterminate Spitz tumors, and Spitzoid melanomas in adults (n = 62) and children (n = 28). The expression profile of 12 miRs in adults (6 miRs in children) was analyzed by real-time polymerase chain reaction. RESULTS: Benign Spitz lesions were characterized by decreased expression of miR-125b and miR-211, and upregulation of miR-22, compared with benign nevi (p < 0.05). A comparison of Spitzoid melanomas to benign nevi revealed overexpression of miR-21, miR-150, and miR-155 in the malignant primaries (p < 0.05). In adults, Spitzoid melanomas exhibited upregulation of miR-21, miR-150, and miR-155 compared with indeterminate Spitz lesions. Indeterminate Spitz lesions with low-risk pathologic features had lower miR-21 and miR-155 expression compared with Spitzoid melanoma tumors in adults (p < 0.05), while pathologic high-risk indeterminate Spitz lesions had increased levels of miR-200c expression compared with low-risk indeterminate lesions (p < 0.05). Pediatric Spitzoid melanomas exhibited increased miR-21 expression compared with indeterminate Spitz lesions (p < 0.05). Moreover, miR-155 expression was increased in indeterminate lesions with mitotic counts >1 and depth of invasion >1 mm, suggesting miR-155 expression is associated with histological characteristics. CONCLUSIONS: miR expression profiles can be measured in indeterminate Spitz tumors and correlate with markers of malignant potential.

Differential mutation frequencies in metastatic cutaneous squamous cell carcinomas versus primary tumors.

BACKGROUND: Exome and targeted sequencing studies have identified potential driver mutations for a variety of tumor types. Cutaneous squamous cell carcinoma (cSCC) is one of the most highly mutated cancers but typically is associated with low rates of metastasis and high survival rates. Nevertheless, metastatic cSCC is a significant health threat; up to 8800 individuals die each year of this disease. METHODS: Because it is difficult to predict which cSCCs are more likely to metastasize, and because to the best of the authors' knowledge there are no targeted therapies specifically designated for patients with metastatic cSCC, exome and/or targeted sequencing of 18 metastatic and 10 primary cSCCs was performed to identify mutations that were more frequent in metastatic tumors and might be targeted for therapeutic benefit. The authors compared their results with published sequencing results of an additional 223 primary tumors and 68 metastatic cSCCs. RESULTS: The authors identified genes demonstrating higher mutation frequencies in metastatic cSCC compared with primary tumors, including the chromatin remodeling gene lysine methyltransferase 2D (KMT2D) and the classic skin tumor suppressor tumor protein p53 (TP53), which was found to be mutated in 54% of primary tumors compared with 85% of metastatic tumors (P<.0001). CONCLUSIONS: These studies appear to uncover potential pathways that are important in metastatic cSCC and that broaden understanding of the biology contributing to aggressive tumor behavior. These results may lead to new therapeutic strategies. Cancer 2017;123:1184-1193. © 2016 American Cancer Society.

Global microRNA profiling for diagnostic appraisal of melanocytic Spitz tumors.

BACKGROUND: Melanoma skin cancer remains the leading cause of skin cancer-related deaths. Spitz lesions represent a subset of melanocytic skin lesions characterized by epithelioid or spindled melanocytes organized in nests. These lesions occupy a spectrum ranging from benign Spitz and atypical Spitz lesions all the way to malignant Spitz tumors. Appropriate management is reliant on accurate diagnostic classification, yet this effort remains challenging using current light microscopic techniques. The discovery of novel biomarkers such as microRNAs (miR) may ultimately be a useful diagnostic adjunct for the evaluation of Spitz lesions. miR expression profiles have been suggested for non-Spitz melanomas but have yet to be ascribed to Spitz lesions. We hypothesized that distinct miR expression profiles would be associated with different lesions along the Spitz spectrum. MATERIALS AND METHODS: RNAs extracted from paraffin-embedded, formalin-fixed tissues of 11 resected skin lesions including benign nevi (n = 2), benign Spitz lesions (n = 3), atypical Spitz lesions (n = 3), and malignant Spitz tumors (n = 3) were analyzed by the NanoString platform for simultaneous evaluation of over 800 miRs in each patient sample. RESULTS: Benign Spitz lesions had increased expression of miR-21-5p and miR-363-3p compared with those of benign nevi. Malignant Spitz lesions exhibited overexpression of miR-21-5p, miR-155-5p, and miR-1283 relative to both benign nevi and benign Spitz tumors. Notably, atypical Spitz tumors had increased expression of miR-451a and decreased expression of miR-155-5p expression relative to malignant Spitz lesions. Conversely, atypical Spitz lesions had increased expression of miR-21-5p, miR-34a-5p, miR-451a, miR-1283, and miR-1260a relative to benign Spitz tumors. CONCLUSIONS: Overall, distinct miR profiles are suggested among Spitz lesions of varying malignant potential with some similarities to non-Spitz melanoma tumors. This work demonstrates the feasibility of this analytic method and forms the basis for further validation studies.

Hair Follicle Nevus With Features of Comedo Nevus: An Expanding Spectrum.

Hair follicle nevus (HFN) is a rare hamartomatous lesion of the folliculosebaceous unit, with or without admixed fibroadipose or muscular tissue. It typically has a congenital presentation in the preauricular area of infants and is frequently confused with an accessory tragus. Acquired tumors with similar histopathologic features have been described infrequently during adolescence and adult life. We report yet another unique presentation of this unusual lesion in a 4-year-old girl who had a long-standing tumor of the nasal columella that started growing rapidly after trauma. Histopathologic examination revealed increased numbers of hair follicles, some of which were associated with diminutive sebaceous glands, with no associated central cystic structure. In addition, the infundibula of the follicles were dilated and filled with keratinous debris. Although these hamartomas are common in the head and neck region, to our knowledge, this is the first report of a HFN at this anatomic location. In addition, this tumor has an overall architecture of a HFN but is accompanied by features of a comedo nevus. We also present a review of the literature and summarize the current diagnostic criteria for HFN.

Allele-specific imbalance mapping identifies HDAC9 as a candidate gene for cutaneous squamous cell carcinoma.

More than 3.5 million nonmelanoma skin cancers were treated in 2006; of these 700,000 were cutaneous squamous cell carcinomas (cSCCs). Despite clear environmental causes for cSCC, studies also suggest genetic risk factors. A cSCC susceptibility locus, Skts5, was identified on mouse chromosome 12 by linkage analysis. The orthologous locus to Skts5 in humans maps to 7p21 and 7q31. These loci show copy number increases in ∼10% of cSCC tumors. Here, we show that an additional 15-22% of tumors exhibit copy-neutral loss of heterozygosity. Furthermore, our previous data identified microsatellite markers on 7p21 and 7q31 that demonstrate preferential allelic imbalance (PAI) in cSCC tumors. On the basis of these results, we hypothesized that the human orthologous locus to Skts5 would house a gene important in human cSCC development and that tumors would demonstrate allele-specific somatic alterations. To test this hypothesis, we performed quantitative genotyping of 108 single nucleotide polymorphisms (SNPs) mapping to candidate genes at human SKTS5 in paired normal and tumor DNAs. Nine SNPs in HDAC9 (rs801540, rs1178108, rs1178112, rs1726610, rs10243618, rs11764116, rs1178355, rs10269422 and rs12540872) showed PAI in tumors. These data suggest that HDAC9 variants may be selected for during cSCC tumorigenesis.

PRMT5 is upregulated in malignant and metastatic melanoma and regulates expression of MITF and p27(Kip1.).

Protein arginine methyltransferase-5 (PRMT5) is a Type II arginine methyltransferase that regulates various cellular functions. We hypothesized that PRMT5 plays a role in regulating the growth of human melanoma cells. Immunohistochemical analysis indicated significant upregulation of PRMT5 in human melanocytic nevi, malignant melanomas and metastatic melanomas as compared to normal epidermis. Furthermore, nuclear PRMT5 was significantly decreased in metastatic melanomas as compared to primary cutaneous melanomas. In human metastatic melanoma cell lines, PRMT5 was predominantly cytoplasmic, and associated with its enzymatic cofactor Mep50, but not STAT3 or cyclin D1. However, histologic examination of tumor xenografts from athymic mice revealed heterogeneous nuclear and cytoplasmic PRMT5 expression. Depletion of PRMT5 via siRNA inhibited proliferation in a subset of melanoma cell lines, while it accelerated growth of others. Loss of PRMT5 also led to reduced expression of MITF (microphthalmia-associated transcription factor), a melanocyte-lineage specific oncogene, and increased expression of the cell cycle regulator p27(Kip1). These results are the first to report elevated PRMT5 expression in human melanoma specimens and indicate this protein may regulate MITF and p27(Kip1) expression in human melanoma cells.

Hidradenoma papilliferum of the orbit.

PURPOSE: Hidradenoma papilliferum (HP) is a cystic lesion of apocrine gland origin that occurs most commonly in the perineal region. Although there are scattered reports of HP involving the eyelid, to our knowledge, we present the first case of HP of the orbit. METHODS: A 63 year-old female presented with progressive left upper eyelid fullness over an 18 month period. RESULTS: The lesion was excised via transconjunctival anterior orbitotomy without incident. CONCLUSIONS: The pathologic features of HP are presented.

Mismatch repair protein deficiency is common in sebaceous neoplasms and suggests the importance of screening for Lynch syndrome.

The association between Lynch syndrome and sebaceous neoplasms is well characterized. The absence of expression of mismatch repair proteins (MMRPs) by immunohistochemistry (IHC) is often used in other Lynch-associated tumors to guide testing. IHC for MLH1, PMS2, MSH2, and MSH6 was performed on 36 benign and malignant sebaceous neoplasms with the absence of one or more MMRP in 38.9% of cases. Among lesions with abnormal IHC, 71.4% were missing both MSH2 and MSH6, 21.4% lacked MLH1 and PMS2, and 7.1% lacked only MSH6. Of the 10 patients with absent MMRP, 5 had gene-test confirmed Lynch syndrome, 3 had no suggestive personal or family medical history and 2 had no recorded data. Tumor-infiltrating lymphocytes in neoplasms with absent MMRP were statistically significantly greater than in those with intact MMRP (16.5 vs. 9.7, P = 0.027). MMRP deficiency is common in sebaceous neoplasms, suggesting the importance of screening for Lynch syndrome in these patients.

Calciphylaxis following coronary artery bypass surgery: an underappreciated cause of wound complications?

Wound complications following cardiac surgery are typically infectious and associated with a high morbidity and mortality. Calciphylaxis, vascular calcification of small and medium sized vessels, often associated with end-stage renal disease, can result in extensive tissue necrosis. We hypothesize that calciphylaxis is an under-recognized and under-reported precipitating wound and breast complication following coronary artery bypass surgery and thereby necessitates further study.

Immunophenotypic diagnosis of primary cutaneous lymphomas: a review for the practicing dermatologist.

The application of CD markers to medicine has advanced our understanding of several dermatological diseases, most notably primary cutaneous lymphomas. CD markers are monoclonal antibodies that target cell surface molecules on leukocytes and antigens from other cells. T-cell processes are typically CD3+, CD20-, CD45+ while B-cell processes are typically CD3-, CD20+, and CD45+. Other CD markers are used to further delineate cutaneous lymphomas. Although an imperfect system, CD markers empower dermatologists to synthesize immunophenotyping with clinical findings and formulate an appropriate diagnosis.

CUL4A abrogation augments DNA damage response and protection against skin carcinogenesis.

It is intuitively obvious that the ability of a cell to repair DNA damage is saturable, either by limitation of enzymatic activities, the time allotted to achieve their function, or both. However, very little is known regarding the mechanisms that establish such a threshold. Here we demonstrate that the CUL4A ubiquitin ligase restricts the cellular repair capacity by orchestrating the concerted actions of nucleotide excision repair (NER) and the DNA damage-responsive G1/S checkpoint through selective degradation of the DDB2 and XPC DNA damage sensors and the p21/CIP1/WAF1 checkpoint effector. We generated Cul4a conditional knockout mice and observed that skin-specific Cul4a ablation dramatically increased resistance to UV-induced skin carcinogenesis. Our findings reveal that wild-type cells do not operate at their full DNA repair potential, underscore the critical role of CUL4A in establishing the cellular DNA repair threshold, and highlight the potential augmentation of cellular repair proficiency by pharmacological CUL4A inhibition.

Merkel cell polyomavirus in cutaneous squamous cell carcinoma of immunocompetent individuals.

Squamous cell carcinoma (SCC) is the second most frequently diagnosed skin cancer. It has a higher incidence in immunosuppressed individuals such as organ transplant recipients and human immunodeficiency virus (HIV) carriers. Recently, a newly described polyoma virus, Merkel cell polyomavirus (MCPyV), was found in Merkel cell carcinoma (MCC), a rare aggressive skin cancer also associated with immunosuppression. We hypothesized that MCPyV would be present in SCCs. To test for the presence of MCPyV in immunocompetent SCC patients, we used PCR primer sets directed against the large T (LT) antigen and VP1 gene of MCPyV. We detected MCPyV in 15% (26/177) of SCC DNA samples and 17% (11/63) of adjacent skin DNA samples from 21 of 58 (36%) individuals studied. We did not detect MCPyV in any matched normal blood DNA (0/57), but observed the presence of MCPyV DNA in 1 of 12 normal mouthwash DNAs. All sequenced SCC samples had a common mutation truncating the LT antigen that provides indirect evidence of viral integration. The presence of MCPyV in approximately 15% of SCCs from immunocompetent individuals warrants evaluation of MCPyV as an etiologic agent in the carcinogenesis of SCC.

Telepathology in Mohs micrographic surgery.

Intraoperative histopathology consultation during Mohs micrographic surgery (MMS) with a dermatopathologist is advantageous in some cases requiring a clarification of a diagnosis but may be difficult because in comparison to the Mohs laboratory, the dermatopathology facility can be remote. Telepathology technology provides a time-efficient means of consultation during MMS via the electronic transmission of pathology images, which can foster case discussions, and expedite the confirmation of diagnosis and treatment decisions.

Genomic analysis defines a cancer-specific gene expression signature for human squamous cell carcinoma and distinguishes malignant hyperproliferation from benign hyperplasia.

Using high-density oligonucleotide arrays, we measured expression of >12,000 genes in surgical excisions of invasive human squamous cell carcinomas (SCCs) versus site-matched control skin. This analysis defined >1,900 genes with altered expression in SCCs that were statistically different from controls. As SCCs are composed of epithelial cells, which are both hyperplastic and invasive, we sought to define gene sets associated with these biologic processes by comparing gene expression to psoriasis vulgaris, which is a condition of benign keratinocyte hyperplasia without invasiveness or pre-malignant potential. Through this analysis, we found genes that were commonly upregulated in both conditions and unique genes with increased expression in SCCs. Differential gene regulation in these two conditions was confirmed by real-time reverse transcription-PCR and immunohistochemistry. We found that benign hyperplasia is associated with upregulation of genes including DEFB4 (defensin B4), SERPINB3 (serine proteinase inhibitor, member 3), STAT1 (signal transducer and activator of transcription 1), K16 (keratin 16), CEACAMs (carcinoembryonic antigen-related cell adhesion molecules), and WNT 5A (wingless-type MMTV integration site family, member 5A). WNT receptor frizzled homolog 6 (FZD6) and prostaglandin-metabolizing enzyme hydroxyprostaglandin dehydrogenase were increased in SCC alone. Growth factor pleiotrophin (PTN) was expressed at higher levels in non-tumor-bearing skin adjacent to excised SCC. SCC was further characterized by upregulation of matrix metalloproteinases 1, 10, and 13, cathepsin L2, cystatin E/M as well as STAT3 and microseminoprotein, beta (MSMB), and downregulation of inducible nitric oxide synthase, granzyme B, CD8, and CD83. The current study defines a unique gene expression signature for cutaneous SCC in humans and suggests potential roles for WNT, FZD, and PTN in the pathogenesis of SCC.

Radiation-induced angiosarcoma after mastectomy and TRAM flap breast reconstruction.

Radiation-induced angiosarcoma of the breast is being reported with increasing frequency as a result of the increased use of radiation therapy in conjunction with breast conservation surgery. However, this entity has not been well documented in patients undergoing mastectomy. The authors present a case of angiosarcoma occurring in a patient 6 years after undergoing mastectomy for invasive duct carcinoma with immediate transverse rectus abdominis musculocutaneous flap reconstruction followed by postoperative radiation therapy. The diagnosis of angiosarcoma was made by skin biopsy performed by the patient's reconstructive surgeon on routine follow-up examination. This is the first reported case of postradiation angiosarcoma occurring in a postmastectomy breast reconstructed with autogenous tissue and it is unusual in that the cancer invaded the musculocutaneous flap. Diagnosis and management recommendations for radiation-induced angiosarcoma are discussed.