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To better understand the natural history of anogenital warts (AGWs) and the dynamics of HPV6/11 infection in regional hairs, 32 newly diagnosed male patients with AGWs and 32 age-matched healthy controls were closely followed. During enrollment and six follow-up visits (every 2.6 months), 43 AGW tissues and 1232 anogenital and eyebrow hair samples were collected. This is the closest longitudinal monitoring of AGW patients to date. Patients were treated according to standards of care. The HPV6/11 prevalence was 19.9% in the patients' hair samples (HPV6 B1 in 53.1%) and 0% in the controls. The highest HPV6/11 prevalence was found in pubic hairs (29.0%) and the lowest in eyebrows (7.1%). The odds of having HPV6/11-positive hairs increased with smoking, shaving the anogenital region, and age. A close association between HPV6/11 presence in hairs and clinically visible AGWs was observed. The proportion of patients with visible AGWs and HPV6/11-positive hairs declined during follow-up with similar trends. No particular HPV6/11 variant was linked with an increased AGW recurrence, but the sublineage HPV6 B1 showed significantly higher clearance from hairs. Despite treatment, 78.1% and 62.5% of the AGW patients experienced one and two or more post-initial AGW episodes, respectively. The patients with HPV6/11-positive hairs or visible AGWs at a preceding visit demonstrated substantially higher odds of presenting with visible AGWs at a subsequent visit.
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Background: There is a broad spectrum of vulvar pigmented lesions that differ based on their histopathological and clinical features. Chronic vulvar purpura is a rare entity, associated with a broad morphological spectrum, from lichen aureus, Zoon's vulvitis, pigmented purpuric dermatosis and with lichen planus as in our case. Case presentation: In this article we discuss a case of an 86-year-old white woman with hyperpigmentation on her upper vulva, next to the introitus, with complaints of urine incontinence. Biopsy revealed subepithelial stromal lichenoid inflammatory infiltrate containing plasma cells, lymphocytes and some neutrophilic granulocytes as well as dilated and congested vessels. Hemosiderin deposits and erythrocyte extravasation were found. There was evidence of hyperkeratosis with hyper granulosis and erosions. Spongiosis was also noted. Few melanocytes were identified with no sign of malignancy. These findings correlate with the diagnosis of vulvar lichen planus. Conclusions: Chronic vulvar purpura is a clinical term used for different chronic inflammatory dermatoses presenting as red bluish or violaceous discolorations on the vulva, often associated with cayenne-pepper-like speckling. Considering a great overlap of possible diseases, the final diagnosis could be challenging. It is important to exclude a melanocytic tumour in these cases.
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Hiperpigmentação , Líquen Plano , Púrpura , Humanos , Feminino , Idoso de 80 Anos ou mais , Líquen Plano/patologia , Vulva/patologia , Púrpura/diagnóstico , Púrpura/patologia , Biópsia , Doença CrônicaRESUMO
BACKGROUND: Wells' syndrome (eosinophilic cellulitis) is an uncommon eosinophilic dermatosis of uncertain pathogenesis, characterized by clinical polymorphism and suggestive but nonspecific histopathologic traits. Its course is recurrent, and response to therapy is unpredictable. In a case in which the patient has a number of potential triggers for the manifestation of Wells' syndrome skin rash, the treating physician must decide or must make an assumption in order to establish the most likely clinical scenario. This is important for the patient's future treatment plans. CASE SUMMARY: We describe the clinical case of a 46-year-old female with chronic lymphocytic leukemia who had already received treatment for several months with ibrutinib. She was diagnosed with Wells' syndrome 10 d after an influenza vaccination containing thimerosal. Based on the literature, the patient was treated with a course of oral steroids. Resolution of clinical symptoms and rash were observed in response to the treatment. Ibrutinib was not discontinued. CONCLUSION: The etiology of Wells' syndrome remains unknown. Clinically, it resembles bacterial cellulitis. Lack of response to antibiotic treatment should lead the physician to consider a diagnosis of Wells' syndrome. Treating the underlying condition is important and may lead to resolution of the syndrome. However, the most common and effective treatment to limit the course of the disease are systemic steroids.
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Human papillomaviruses (HPVs) are etiologically associated with various benign and malignant neoplasms of cutaneous and mucosal epithelia. We describe an improved diagnostic protocol for comprehensive characterization of causative HPV types in common warts, in which broad-spectrum PCRs followed by Sanger sequencing, two previously described and seven newly developed type-specific quantitative real-time PCRs (qPCRs) coupled with the human beta-globin qPCR were used for: (i) diagnosis of HPV infection in warts; (ii) estimation of cellular viral loads of all HPV types detected; and (iii) determination of their etiological role in 128 histologically confirmed fresh-frozen common wart tissue samples. A total of 12 different causative HPV types were determined in 122/126 (96.8%) HPV-positive warts, with HPV27 being most prevalent (27.0%), followed by HPV57 (26.2%), HPV4 (15.1%), HPV2 (13.5%), and HPV65 (7.9%). The cellular viral loads of HPV4 and HPV65 were estimated for the first time in common warts and were significantly higher than the viral loads of HPV2, HPV27, and HPV57. In addition, we showed for the first time that HPV65 is etiologically associated with the development of common warts in significantly older patients than HPV27 and HPV57, whereas HPV4-induced warts were significantly smaller than warts caused by HPV2, HPV27, HPV57, and HPV65.
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Alphapapillomavirus , Infecções por Papillomavirus , Verrugas , Humanos , Papillomaviridae/genética , Verrugas/patologia , Reação em Cadeia da Polimerase em Tempo Real , Globinas beta , DNA Viral/genéticaRESUMO
BACKGROUND: The ampulla of Vater is an anatomically and histologically complex region giving rise to a heterogenous group of tumors. This is, to the best of our knowledge, the first case of intra-ampullary papillary-tubular neoplasm combined with ampullary neuroendocrine carcinoma reported in the literature. CASE SUMMARY: A 61-year-old woman presented to the emergency department for evaluation of painless jaundice. Contrast-enhanced computed tomography (CT) of the abdomen and chest showed a periampullary tumor mass measuring 15 mm × 12 mm × 14 mm, with no evidence of locoregional and distant metastases, for which she underwent pancreatoduodenectomy. Histopathologic examination of a resected specimen revealed an intra-ampullary papillary tubular neoplasm with high-grade dysplasia in combination with poorly differentiated grade 3 neuroendocrine carcinoma with a mitotic count of more than 20 mitoses per 10 high power fields and Ki-67 index of 100%. No positive lymph nodes were identified. Her postoperative course was uneventful. Postoperatively, she remained under close surveillance. Multiple liver metastases were observed on follow-up CT 8 mo after the surgery, so systemic therapy with cisplatin and etoposide was initiated. CONCLUSION: The simultaneous occurrence of neuroendocrine and non-neuroendocrine tumors in the ampulla of Vater is rare and the pathogenesis of such tumors is largely unknown. Due to unpredictable clinical behavior and lack of solid evidence on optimal treatment strategy, close patient surveillance is advised after radical resection of the primary tumor.
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Strongyloides stercoralis causes chronic, mostly asymptomatic infections but hyperinfection syndrome may occur in immunosuppressed patients, especially in those receiving corticosteroids. We report a case of S. stercoralis hyperinfection syndrome in a solid organ transplant recipient that occurred approximately 2.5 months after heart transplantation. The patient presented to the intensive care unit with acute respiratory distress, bacteremia, and petechial rash on abdomen and toe. Microbiology testing of respiratory samples excluded infection with Pneumocystis jirovecii, respiratory viruses, pathogenic bacteria and fungi. No eosinophilia was found. Histopathological examination of the skin biopsy of the petechial rash provided the first indication of the diagnosis, revealing the presence of isolated filariform S. stercoralis larvae in the dermis. Subsequent microbiology testing confirmed the diagnosis. This case highlights the role of histopathological examination of a skin rash in diagnosing patients with atypical clinical presentation of Strongyloides hyperinfection syndrome.
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Eosinofilia , Exantema , Strongyloides stercoralis , Estrongiloidíase , Animais , Eosinofilia/diagnóstico , Eosinofilia/etiologia , Humanos , Hospedeiro Imunocomprometido , Estrongiloidíase/complicações , Estrongiloidíase/diagnóstico , SíndromeRESUMO
Cutaneous vasculitis is a recognized and potentially serious adverse event of immunization with several vaccines, and COVID-19 vaccines are no exception. We present a case of cutaneous leukocytoclastic vasculitis occurring 17 days after inoculation with adenoviral vector vaccine (Ad26.COV2.S) in a previously healthy 30-year-old patient with no history of prior adverse events following vaccination. Transient laboratory abnormalities (mild proteinuria, cryoglobulinemia, and slightly diminished C3 complement level) were also noted, but they resolved with the resolution of skin changes after treatment with topical steroids. Although the frequency of cutaneous vasculitis after COVID-19 vaccines is extremely low, it presents an important challenge for the clinician when faced with an uncertain and delicate decision whether these patients can safely receive booster doses of COVID-19 vaccine. Because vaccination certificates are necessary for day-to-day activities and have a limited validity date, this may be an uncomfortable issue.
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COVID-19 , Vacinas , Vasculite Leucocitoclástica Cutânea , Ad26COVS1 , Adulto , Vacinas contra COVID-19/efeitos adversos , Humanos , Vacinação , Vasculite Leucocitoclástica Cutânea/etiologiaRESUMO
Palisaded neutrophilic granulomatous dermatitis (PNGD) is a rare histopathological pattern belonging to a group of cutaneous granulomatous eruptions that typically manifests with asymptomatic skin-colored, erythematous, or violaceous papules or nodules. PNGD can be triggered by various systemic conditions, including medications and autoimmune and autoinflammatory disorders, as well as malignancies; for example, lymphoproliferative disorders. Therefore, in patients with PNGD an extended diagnostic workup is mandatory as well as follow-up in the case of idiopathic PNGD. To the best of our knowledge, this is the first reported case in the literature of PNGD causally related to a relapse of HLA-B27-negative axial spondyloarthritis.
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Doenças Autoimunes , Espondiloartrite Axial , Dermatite , Doenças Autoimunes/complicações , Dermatite/complicações , Granuloma/complicações , Granuloma/diagnóstico , Antígeno HLA-B27/uso terapêutico , HumanosRESUMO
We report 21 cases of trichogerminoma harbouring previously undescribed FOXK1::GRHL1/2 or GPS2::GRHL1/2/3 in-frame fusion transcripts. Microscopic examination of a preliminary set of five cases revealed well-delimitated tumours located in the dermis with frequent extension to the subcutaneous tissue. Tumours presented a massive and nodular architecture and consisted of a proliferation of basaloid cells. A biphasic pattern sometime resulting in tumour cell nests ('cell balls') was present. Immunohistochemistry demonstrated the expression of cytokeratins (CKs) 15, 17, and PHLDA1. In addition, numerous CK20-positive Merkel cells were detected. RNA sequencing (RNA-seq) revealed a FOXK1::GRHL1 chimeric transcript in three cases and a FOXK1::GRHL2 fusion in two cases. In a second series for validation (n = 88), FOXK1::GRHL1/2 fusion transcripts were detected by RT-qPCR or FISH in an additional 12 trichogerminomas and not in any other follicular tumour entities or basal cell carcinoma cases (n = 66). Additional RNA-seq analysis in trichogerminoma cases without detected FOXK1::GRHL1/2 rearrangements revealed GPS2::GRHL1 fusion transcripts in two cases, GPS2::GRHL2 in one case, and GPS2::GRHL3 fusion transcript in one case. Therefore, our study strongly suggests that GRHL1/2/3 gene rearrangements might represent the oncogenic driver in trichogerminoma, a subset of follicular tumours characterized by immature features and numerous Merkel cells. © 2022 The Pathological Society of Great Britain and Ireland.
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Neoplasias Cutâneas , Fatores de Transcrição Forkhead/genética , Rearranjo Gênico , Humanos , Imuno-Histoquímica , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Reino UnidoRESUMO
Introduction: Primary hepatic leiomyoma (PHL) is a rare benign hepatic tumor with unclear pathogenesis. It more commonly occurs in immunosuppressed patients, while only 24 cases have been described among immunocompetent individuals. To date, only one successful preoperative diagnosis of PHL has been achieved. Case Presentation: Here we report a case of PHL in a middle-aged woman with no history of immunosuppression. Preoperative diagnosis of PHL was established using ultrasound-guided fine needle trucut biopsy (FNTB). Nevertheless, due to the growing nature of tumor and patient's symptoms, we proceeded with surgical resection, which confirmed the diagnosis of PHL. At 6-month follow up, the patient is in good condition with no evidence of tumor recurrence. Conclusions: PHL is an uncommon tumor that should be considered in the differential diagnosis of rare liver tumors. Image guided FNTB appears to be effective in achieving preoperative diagnosis of PHL. Surgical resection, however, remains both diagnostic and curative in the management of PHL.
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The aim of the paper is to give an update on molecular genetic aberrations in Spitz melanocytic proliferations with special emphasis on their correlation with morphological features and biological behavior. The Spitz group of melanocytic proliferations is defined by a combination of distinctive morphological features and driver molecular genetic events. Morphologically, these neoplasms are characterized by large, oval, polygonal, or spindled melanocytes with abundant eosinophilic cytoplasm, vesicular nuclei with prominent nucleoli, often in association with epidermal hyperplasia. Molecular aberrations in Spitz melanocytic proliferations can be divided into two main groups, according to the driver genetic change: 1) 11p amplification/HRAS mutation, present in about 20% of cases, and 2) kinase fusions, present in about 50%, further subdivided into tyrosine kinase fusions (ALK, ROS1, NTRK1, NTRK3, MET, RET) or serine-threonine kinase fusions (MAP3K8, BRAF). Driver genetic aberrations can be detected along the whole biological spectrum of Spitz melanocytic proliferations, and are mutually exclusive. Although driver genetic aberrations enable proliferation of melanocytes, additional genetic events (often biallelic inactivation of CDKN2A and TERT promoter mutations) are necessary for the development of overt Spitz malignancy. CONCLUSIONS: Recent studies have demonstrated that certain driver genetic aberrations are more often associated with the benign spectrum of Spitz melanocytic proliferations and indolent biological behavior (11p amplification/HRAS mutation, tyrosine kinase fusions). In contrast, some driver aberrations are more frequent in the atypical/malignant spectrum of Spitz melanocytic proliferations with a potential for aggressive biological behavior (serine-threonine kinase fusions). In addition, certain driver aberrations are often associated with distinctive morphological features. However, none of the morphological features is entirely specific for any of these driver genetic aberrations. Immunohistochemistry for ALK, ROS1, and pan-TRK can be used for screening purposes to detect corresponding fusion proteins.
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Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Proliferação de Células/genética , Humanos , Biologia Molecular , Nevo de Células Epitelioides e Fusiformes/genética , Proteínas Tirosina Quinases , Proteínas Proto-Oncogênicas , Neoplasias Cutâneas/genéticaRESUMO
Fibroma of tendon sheath (FTS) is an uncommon benign myofibroblastic neoplasm that arises in association with tenosynovial tissue. Fusions of the USP6 gene have been recently documented in a proportion of so-called "cellular FTS" but not in "classic FTS". It remains unknown whether FTS can be defined by a USP6 fusion, regardless of cellularity, and what are USP6 fusion-negative "cellular FTS". Furthermore, FTS with low cellularity seems to be frequently confused with desmoplastic fibroblastoma. We performed a comprehensive analysis, including targeted RNA sequencing, of 58 consecutive cases originally diagnosed as FTS (n = 49), desmoplastic fibroblastoma (n = 6), or nodular fasciitis (n = 3); the latter two at the predilection sites for FTS. After review of the original slides, 28 lesions were morphologically classified as FTS (13 "classic" and 15 "cellular") and 23 as desmoplastic fibroblastoma. Among originally diagnosed FTS at the more cellular end of the spectrum, we identified seven lesions that shared many morphologic features of FTS but, in addition, showed several distinct morphologic features consistent with myofibroma, such as myoid appearance, branching thin-walled vessels, and perivascular growth. Targeted RNA sequencing showed a USP6 fusion in 17 of 18 analyzed FTS, regardless of cellularity, 0 of 5 desmoplastic fibroblastomas and 0 of 4 myofibromas. MYH9, COL1A1, and ASPN were identified as fusion partners in three cases each, and MIR22HG, CTNNB1, SPARC, CAP1, EMP1, LINC00152, NR1D1, and RAB1A in a single case each. FTS, regardless of cellularity, can be defined by a USP6 fusion with a variety of fusion partners. More cellular lesions exhibiting some morphologic features of FTS but lacking a USP6 fusion tend to be myofibromas.
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Miofibroma/patologia , Fusão Oncogênica , Neoplasias de Tecidos Moles/patologia , Tendões/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miofibroma/genética , Neoplasias de Tecidos Moles/genética , Adulto JovemRESUMO
Chronic venous ulcers affect 1% of the adult population and are associated with a marked reduction in quality of life, especially if healing is prolonged. Several matrix metalloproteinases (MMPs) appear to be involved in the pathophysiology of chronic venous ulcer healing, but their exact role is still unclear. Cyclooxygenase-2 (COX-2) is an important enzyme in prostanoid synthesis, induced during inflammation in chronic venous ulcer. The first aim of our study was to compare the expression of MMP-1, MMP-2, and COX-2 in wound tissue to that in normal skin. The second aim was to observe the expression of the above factors in 29 chronic venous ulcers in 22 patients at the beginning and 4 weeks later in relation to healing rates and final healing outcome after 24 weeks. The enrolled population was divided into two groups, healed and non-healed wounds after 24 weeks. The intensity of expression of MMP-1, MMP-2 and COX-2 was assessed for each ulcer in paired wound biopsy samples and wound size measurements using laser triangulation at the beginning and after 4 weeks of observation. Initial healing rates in the first 4 weeks were calculated and proved to be an important predictive factor of healing in 24 weeks. Decreases in MMP-1 and MMP-2 after 4 weeks of observation were distinct, positive predictors for ulcer healing. Healing odds were 3.7 times higher for a decrease in MMP-1 and 2.1 times higher for a decrease in MMP-2 compared to the healing odds for a non-decrease in MMP-1 and MMP-2. In conclusion, a decrease in MMP-1 and MMP-2, but not COX-2, in wound biopsy samples after 4 weeks of observation can predict better healing of chronic venous ulcer.
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Úlcera Varicosa , Adulto , Doença Crônica , Ciclo-Oxigenase 2 , Humanos , Metaloproteinase 1 da Matriz , Metaloproteinase 2 da Matriz , Metaloproteinases da Matriz , Qualidade de Vida , Úlcera , CicatrizaçãoRESUMO
The recent WHO classification of skin tumors has underscored the importance of acknowledging intermediate grade melanocytic proliferations. A multistep acquisition of oncogenic events drives the progressive transformation of nevi into melanomas. The various pathways described are modulated by the initial oncogenic drivers that define the common, blue, and Spitz nevi groups. Intermediate lesions are most often the result of a clonal evolution within such nevi. Based on this established classification, we have suggested for each pathway a practical diagnostic approach, benefiting from the recently developed molecular tools, both in the setting of general pathology labs and expert centers. Moreover, recommendations regarding the re-excision and clinical follow-up are given to support decision-making in multidisciplinary tumor boards.
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Biomarcadores Tumorais/genética , Proliferação de Células , Técnicas de Apoio para a Decisão , Melanócitos/patologia , Melanoma/genética , Técnicas de Diagnóstico Molecular , Nevo Pigmentado/genética , Neoplasias Cutâneas/genética , Adulto , Tomada de Decisão Clínica , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Melanoma/patologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Gradação de Tumores , Nevo Pigmentado/patologia , Nevo Pigmentado/cirurgia , Fenótipo , Valor Preditivo dos Testes , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Unproven stem cell treatments may involve serious health, personal, and financial considerations. Due to worldwide spread, illegal stem cell therapies have become a major public health problem. We have already witnessed numerous reports in the mass media of severe and occasionally even fatal outcomes after such therapies. However, there are only few scientifically documented cases in which the causality between stem cell therapy and side effects cannot be refuted. CASE PRESENTATION: Here we present a case report of a 48-year-old patient with serious side effects, including disseminated skin ulcers, hepatitis, and cardiomyopathy, with eventual fatal outcome following unproven stem cell treatment. CONCLUSIONS: The case of the patient presented here draws attention to the worst possible outcome of stem cell tourism. To effectively combat this issue, professionals and patients should be empowered with the right knowledge on possible side effects.
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Cardiomiopatias/epidemiologia , Hepatite/epidemiologia , Úlcera Cutânea/epidemiologia , Transplante de Células-Tronco/efeitos adversos , Calciofilaxia/epidemiologia , Calciofilaxia/etiologia , Calciofilaxia/patologia , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Hepatite/etiologia , Hepatite/patologia , Humanos , Masculino , Turismo Médico , Pessoa de Meia-Idade , Úlcera Cutânea/etiologia , Úlcera Cutânea/patologiaRESUMO
Pure intravascular growth of epithelioid hemangioma (EH) is exceptional. Herein, we report a series of 21 intravascular EHs, representing a potential serious diagnostic pitfall by mimicking malignant vascular neoplsms with epithelioid morphology. The tumors developed in 12 males and 4 females, aged from 11 to 71 years (mean age 40.2 years) with a predilection for the extremities (13 of 21, 61.9%), followed by the head and neck (8 of 21, 38.1%). Lesions ranged in size from 2 to 30 mm (mean size 13 mm). The most common presenting feature was a slowly growing nodule. Most neoplasms were solitary (13 of 16 patients, 81.2%) but three patients developed more than one intravascular EH (3 of 16, 18.8%). Treatment consisted of complete surgical excision and was generally curative. Follow-up was available for 13 lesions that had developed in ten patients (range 4-72 months, mean 27.3 months). No recurrences or development of additional tumors were observed. All 21 lesions developed in subcutaneous veins. Two morphological patterns of intravascular epithelioid endothelial cell proliferation were observed: (1) a lobular capillary hemangioma-like proliferation with variable formation of open vascular lumina and (2) a solid proliferation generally lacking open vascular spaces. A lobular capillary hemangioma-like pattern was the sole pattern in nine lesions, a mixed lobular hemangioma-like pattern, and solid pattern in eight and a pure solid pattern in four intravascular EHs. Mitotic activity in epithelioid endothelial cells ranged from 0 to 7 mitoses per 10 high-power field (mean 2.1 mitoses per 10 HPFs). Six lesions displayed brisk mitotic activity of five or more mitoses per 10 HPF (6 of 21, 28.5%). The number of mitoses was usually more prominent in areas with solid growth. Atypical mitoses were not observed. No intratumoral necroses were seen. Cytological atypia was mild (20 out of 21 cases). By immunohistochemistry, all tumors were positive for CD31 (14 out of 14) and ERG (5 out of 5). While all tested cases were FOS negative by immunohistochemistry (6 out of 6), one out of six cases (case 6) displayed FOSB nuclear positivity in about 30% of the lesional endothelial cells. Eight cases were analysed by FISH for the presence of FOS and FOSB gene rearrangements. While all cases were negative for FOSB rearrangements, a single case proved positive for FOS gene break-apart. In conclusion, intravascular growth of EH is not associated with adverse biological behavior. Solid intravascular proliferations of endothelial cells can mimic a malignant vascular tumor with epithelioid morphology. Nevertheless, intravascular EHs display mild cytological atypia coupled with low mitotic activity, and a lack of atypical mitoses, pronounced nuclear atypia, multilayering or tumor necrosis. Finally, the FOS gene is infrequently rearranged, and there are no FOSB gene abnormalities in this subset of EHs, suggesting a potential distinct pathogenesis than most classic EHs.
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Hiperplasia Angiolinfoide com Eosinofilia/patologia , Tela Subcutânea/patologia , Adolescente , Adulto , Idoso , Hiperplasia Angiolinfoide com Eosinofilia/genética , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Background: Assessment of human papillomavirus (HPV) type-specific viral load (VL) is a valid tool for determining the etiology of HPV-related skin tumors, especially when more than one HPV type is detected within one lesion. Methods: The causative HPV type was determined in 185 fresh-frozen tissue specimens of histologically confirmed common warts (CWs) collected from 121 immunocompetent patients. All tissues were tested using the type-specific quantitative real-time polymerase chain reactions (PCR) for the most common wart-associated Alpha-PV (HPV2/27/57) and Mu-PV types (HPV1/63/204). The presence of 23 additional low-risk HPVs was evaluated using a conventional wide-spectrum PCR. Results: HPV DNA was detected in 176/185 (95.1%) CWs and multiple HPV types in 71/185 (38.4%) lesions. Using the VL approach and a robust cutoff of one viral copy/cell established in this study, HPV2/27/57 were determined as causative agents in 41/53 (77.3%) and 53/71 (74.7%) CWs with single and multiple HPVs, respectively. Conclusions: CWs are mostly etiologically associated with HPV2/27/57 and only rarely with HPV1. In the majority of CWs containing multiple HPVs, a single HPV type was present in high concentration, indicating etiological association. No significant differences in VLs of lesion-causing HPV types in CWs containing single or multiple HPVs were found.