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Neurofibromas (NFs), Bowen disease (BD), and seborrheic keratosis (SK) are common skin tumors. Pathologic examination is the gold standard for diagnosis of these tumors. Current pathologic diagnosis is primarily based on microscopic observation, which is laborious and time-consuming. With digitization, artificial intelligence can be used to improve the efficiency of pathologic diagnosis. This research aims to develop an end-to-end extendable framework for the diagnosis of skin tumor based on pathologic slide images. NF, BD, and SK were selected as target skin tumors. A two-stage skin cancer diagnosis framework is proposed in this article, which consists of two parts: patches-wise diagnosis, and slide-wise diagnosis. Patches-wise diagnosis compares different convolutional neural networks to extract features and distinguish categories from patches generated in whole slide images. Slide-wise diagnosis combines attention graph gated network model prediction with post-processing algorithm. This approach can fuse information from feature-embedding learning and domain knowledge to draw conclusions. Training, validation, and testing were performed on NF, BD, SK, and negative samples. Accuracy and receiver operating characteristic curves were used to evaluate the classification performance. This study investigated the feasibility of skin tumor diagnosis from pathologic images and may be the first instance of applying deep learning to address these three types of tumor diagnoses in skin pathology.
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Aprendizado Profundo , Neoplasias Cutâneas , Humanos , Inteligência Artificial , Neoplasias Cutâneas/diagnóstico , Redes Neurais de Computação , AlgoritmosRESUMO
BACKGROUND: The differential diagnosis of atypical dermal nonepidermotropic CD8+ lymphocytic infiltrates includes a heterogeneous spectrum of lymphoproliferations with overlapping histological and phenotypic features, but divergent clinical manifestations and prognoses. As these neoplasms are rare, more data on their clinicopathological presentation and course are needed. OBJECTIVES: To assess the clinical, histological and immunophenotypic features; outcomes of; and differences between dermal CD8+ lymphoproliferations. METHODS: Retrospective analysis of a series of 46 patients and biopsies by the international EORTC Cutaneous Lymphoma Group. RESULTS: The dermal CD8+ lymphoproliferations (n = 46) could be assigned to one of three groups: (i) cutaneous acral CD8+ T-cell lymphoma (n = 31), characterized mostly by a solitary nodule arising at acral sites, a monotonous dermal infiltrate of small-to-medium-sized CD8+ lymphocytes with a characteristic dot-like pattern of CD68, a low proliferation rate and an excellent prognosis; (ii) primary cutaneous CD8+ peripheral T-cell lymphoma, unspecified/NOS (n = 11), presenting with one or multiple rapidly evolving tumours, mostly medium-sized pleomorphic CD8+ tumour cells with expression of several cytotoxic markers, and high proliferative activity; and (iii) cutaneous CD8+ lymphoproliferations (n = 4), associated with congenital immunodeficiency syndromes in two patients with persisting localized or disseminated violaceous to brownish plaques on the extremities, a histiocyte-rich infiltrate of mostly small CD8+ lymphocytes with subtle atypia and a protracted course; and papular CD8+ eruptions in two patients with acquired immunosuppression. CONCLUSIONS: A constellation of distinct clinical, histopathological and phenotypic features allows discrimination and assignment of dermal CD8+ infiltrates into distinct disease entities. Primary cutaneous acral CD8+ lymphoma, assigned a provisional category in current lymphoma classifications, is a distinct and reproducible entity. A correct diagnosis is essential to avoid unnecessarily aggressive treatment for indolent CD8+ lymphoproliferations and to identify cases with underlying immuno-deficiency or potential for dismal outcome.
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Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Linfócitos T CD8-Positivos/patologia , Humanos , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/patologia , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/patologiaRESUMO
The membrane electrode assembly (MEA) plays an important role in the proton exchange membrane fuel cell (PEMFC) performance. Typically, the structure comprises of a polymer electrolyte membrane sandwiched by agglomerate catalyst layers at the anode and cathode. Optimization of various parameters in the design of MEA is, thus, essential for reducing cost and material usage, while improving cell performance. In this paper, optimization of MEA is performed using a validated two-phase PEMFC numerical model. Key MEA parameters affecting the performance of a single PEMFC are determined from sensitivity analysis and are optimized using the response surface method (RSM). The optimization is carried out at two different operating voltages. The results show that membrane thickness and membrane protonic conductivity coefficient are the most significant parameters influencing cell performance. Notably, at higher voltage (0.8 V per cell), the current density can be improved by up to 40% while, at a lower voltage (0.6 V per cell), the current density may be doubled. The results presented can be of importance for fuel cell engineers to improve the stack performance and expedite the commercialization.
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Fontes de Energia Bioelétrica , Eletroquímica/instrumentação , Eletrodos , Membranas ArtificiaisRESUMO
Owing to its relatively high heat transfer performance and simple configurations, liquid cooling remains the preferred choice for electronic cooling and other applications. In this cooling approach, channel design plays an important role in dictating the cooling performance of the heat sink. Most cooling channel studies evaluate the performance in view of the first thermodynamics aspect. This study is conducted to investigate flow behaviour and heat transfer performance of an incompressible fluid in a cooling channel with oblique fins with regards to first law and second law of thermodynamics. The effect of oblique fin angle and inlet Reynolds number are investigated. In addition, the performance of the cooling channels for different heat fluxes is evaluated. The results indicate that the oblique fin channel with 20° angle yields the highest figure of merit, especially at higher Re (250-1000). The entropy generation is found to be lowest for an oblique fin channel with 90° angle, which is about twice than that of a conventional parallel channel. Increasing Re decreases the entropy generation, while increasing heat flux increases the entropy generation.
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Hidroacanthoma simplex (HS) is a rare skin appendage tumor that typically appears on the trunk and lower limbs in the elderly. Although HS is a predominantly benign condition, the presence of cellular atypia and dermal infiltration on histological examination indicates malignant HS (MHS). 5-aminolaevulinic acid photodynamic therapy (ALA-PDT) uses a photosensitizer and corresponding light source to cause irreversible damage or death of target cells through a photochemical reaction. Here, we reported the successful treatment of a MHS patient with ALA-PDT using plum-blossom needle pretreatment combined with CO2 laser. After five courses of ALA-PDT, the lesions were completely resolved, and the autonomic activity and smooth surface of the left ring finger were restored. This suggests that ALA-PDT is an effective, minimally invasive and safe treatment modality for MHS.
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The gas therapy is drawing increasing attention in the treatment of many diseases including cancer. As one of gas signaling molecules, carbon monoxide (CO) has been proved to exert anti-cancer effects via triggering multiple cell death types, such as autophagy, apoptosis and necrosis. Here, we showed that low concentration CO delivered from CO-releasing molecule 3 (CORM-3) effectively induced ferroptosis, known as a novel proinflammatory programmed cell death, in vitro and in vivo. Mechanistically, we found that CO triggered ferroptosis by modulating the ROS/GSK3ß/GPX4 signaling pathway, resulting in the accumulation of lipid hydroperoxides and the occurrence of ferroptosis. We think our findings provide novel insights into the anti-cancer mechanisms of CO, and suggest that CO could potentially be exploited as a novel ferroptosis inducer for cancer treatment in the future.
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BACKGROUND: Actinic keratosis (AK) is prevalent and has been widely studied in fair-skinned populations. However, this is not the case in eastern countries. AK in Asians has not been so thoroughly investigated. OBJECTIVES: To analyse the clinical and pathological features of a relatively large number of cases of AK diagnosed in older Chinese patients. METHODS: Case histories of 328 patients with pathologically diagnosed AK were analysed retrospectively. Their demographic, clinical, pathological and treatment data were collected for analysis of associated factors. RESULTS: Lesions were usually distributed on the face, especially the cheeks and temples. The most frequent pathological type was hypertrophic. Only 34% of the cases had been diagnosed correctly as AK before biopsy; many were mistaken for seborrhoeic keratosis. CONCLUSIONS: Most patients were elderly females and there was a higher incidence of lesions on the face, and a lower incidence on the extremities and trunk; this finding contrasts with previous investigations in fair-skinned people.
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Povo Asiático , Erros de Diagnóstico , Dermatoses Faciais/patologia , Ceratose Actínica/patologia , Pele/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biópsia , China , Feminino , Humanos , Hipertrofia/patologia , Ceratose Actínica/diagnóstico , Ceratose Actínica/terapia , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tronco , Extremidade SuperiorRESUMO
Primary cutaneous mucormycosis is an uncommon disease and occurs mainly in patients with immunocompromised disorders. We report a case of cutaneous mucormycosis in an immunocompetent man in whom no definite precipitating factors were noted. The isolate was identified as Rhizomucor variabilis according to the fungus morphology and DNA sequencing results. The lesion was successfully treated with oral Itraconazole, although the in vitro drug-susceptibility test showed resistance.
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Imunocompetência , Mucormicose/microbiologia , Rhizomucor/fisiologia , Antifúngicos/uso terapêutico , Humanos , Itraconazol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mucormicose/tratamento farmacológicoRESUMO
Mutations in the BRAF serine/threonine kinase gene are frequently found in cutaneous melanomas. Activation of hypoxia inducible factor-1alpha (HIF-1alpha) in response to both hypoxic stress and oncogenic signals has important implications in cancer development and progression. Here, we report that mutant BRAF(V600E) increases HIF-1alpha expression in melanoma cells. Our microarray profiling data in 35 melanoma and melanocyte cell lines showed that HIF-1alpha gene expression was significantly increased in melanomas harboring BRAF(V600E) mutation. Stable suppression of mutant BRAF(V600E) or both wild-type and mutant BRAF(V600E) by RNA interference in melanoma cells resulted in significantly decreased HIF-1alpha expression. Knockdown of mutant BRAF(V600E) induced significant reduction of cell survival and proliferation under hypoxic conditions, whereas knockdown of both wild-type and mutant BRAF(V600E) resulted in further reduction. The effects of BRAF knockdown can be rescued by reintroducing BRAF(V600E) into tumor cells. Transfection of BRAF(V600E) into melanoma cells with wild-type BRAF induced significantly more hypoxic tolerance. Knockdown of HIF-1alpha in melanoma cells resulted in decreased cell survival under hypoxic conditions. Pharmacologic inhibition of BRAF by BAY 43-9006 also resulted in decreased HIF-1alpha expression. Although HIF-1alpha translational rate was not changed, the protein was less stable in BRAF knockdown cells. In additional, von Hippel-Lindau protein expression was significantly increased in BRAF knockdown cells. Our data show for the first time that BRAF(V600E) mutation increases HIF-1alpha expression and melanoma cell survival under hypoxic conditions and suggest that effects of the oncogenic V600E BRAF mutation may be partially mediated through the HIF-1alpha pathway.
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Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Melanoma/enzimologia , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Benzenossulfonatos/farmacologia , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Melanoma/genética , Melanoma/patologia , Niacinamida/análogos & derivados , Compostos de Fenilureia , Piridinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Sorafenibe , Transfecção , Regulação para CimaRESUMO
Wet shotcrete can reduce dust and improve supporting strength, however, safe and efficient pipage is a key technical part of wet shotcrete process. The paper studied the pipe flow law of wet shotcrete based on lubrication layer by build the experimental pumping circuit of wet shotcrete that can carry out a number of full-scale pumping tests. The experimental results show there was a linear relationship between pressure loss and flow rate. Combined with the Buckingham rheological equation, the computing equations of the yield shear stress and plastic viscosity were deduced through linear regression. A simple analytical method allowing for a rough estimation of the pumping pressure was proposed and used when considering the lubrication layer of wet shotcrete in pipes. In addition, two kinds of particulate distributive models were established along the time axial to analyze the formation of lubrication layer which is related with particles migration. By computational fluid dynamics simulation, the lubrication layer thickness of different mix proportions was estimated. A new method for measuring the thickness of lubrication layer was proposed to verify it by binarization processing. Finally, according to the comparative analysis of experiments, simulation and computed value, it can be seen that the lubrication layer plays a key role in the process of wet shotcrete flow and with the increase of lubrication layer thickness pipe pressure declines gradually.
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A case of D-penicillamine(DPA) induced elastosis perforans serpiginosa(EPS) in a 32-year-old Chinese man was reported. The presentation lasted two years and was refractory to traditional medical treatment. He was then commenced on 7.6% 5-aminolevulinic acid (ALA) induced photodynamic therapy(PDT) by a LED light of 633 nm at dose levels of 130J/ cm2 for each session with total 3 sessions at one week interval. The patient was tolerated and responded well to this new approach for DPA-induced EPS without any adverse events. The etiology, pathophysiology, natural history, and treatment options for DPA-induced EPS are reviewed, and the authors suggest this method of treatment to be effective and safe for patients of DPA-induced EPS refractory to conventional therapy.
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Ácido Aminolevulínico/uso terapêutico , Penicilamina/efeitos adversos , Fotoquimioterapia/métodos , Dermatopatias/induzido quimicamente , Dermatopatias/tratamento farmacológico , Adulto , Quelantes/administração & dosagem , Quelantes/efeitos adversos , Humanos , Masculino , Penicilamina/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Prurido/complicações , Prurido/tratamento farmacológico , Dermatopatias/patologia , Resultado do TratamentoRESUMO
Extramammary Paget's disease (EMPD) is a rare cutaneous malignancy accounting for approximately 1-2% of vulvar cancers. The rarity of this disease has caused difficulties in characterization and the molecular mechanism underlying EMPD development remains largely unclear. Here we used microarray analysis to identify differentially expressed genes in EMPD of the scrotum comparing with normal epithelium from healthy donors. Agilent single-channel microarray was used to compare the gene expression between 6 EMPD specimens and 6 normal scrotum epithelium samples. A total of 799 up-regulated genes and 723 down-regulated genes were identified in EMPD tissues. Real-time PCR was conducted to verify the differential expression of some representative genes, including ERBB4, TCF3, PAPSS2, PIK3R3, PRLR, SULT1A1, TCF7L1, and CREB3L4. Generally, the real-time PCR results were consistent with microarray data, and the expression of ERBB4, PRLR, TCF3, PIK3R3, SULT1A1, and TCF7L1 was significantly overexpressed in EMPD (P<0.05). Moreover, the overexpression of PRLR in EMPD, a receptor for the anterior pituitary hormone prolactin (PRL), was confirmed by immunohistochemistry. These data demonstrate that the differentially expressed genes from the microarray-based identification are tightly associated with EMPD occurrence.
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Porokeratosis (PK) is a heterogeneous group of keratinization disorders. No causal genes except MVK have been identified, even though the disease was linked to several genomic loci. Here, we performed massively parallel sequencing and exonic CNV screening of 12 isoprenoid genes in 134 index PK patients (61 familial and 73 sporadic) and identified causal mutations in three novel genes (PMVK, MVD, and FDPS) in addition to MVK in the mevalonate pathway. Allelic expression imbalance (AEI) assays were performed in 13 lesional tissues. At least one mutation in one of the four genes in the mevalonate pathway was found in 60 (98%) familial and 53 (73%) sporadic patients, which suggests that isoprenoid biosynthesis via the mevalonate pathway may play a role in the pathogenesis of PK. Significantly reduced expression of the wild allele was common in lesional tissues due to gene conversion or some other unknown mechanism. A G-to-A RNA editing was observed in one lesional tissue without AEI. In addition, we observed correlations between the mutations in the four mevalonate pathway genes and clinical manifestations in the PK patients, which might support a new and simplified classification of PK under the guidance of genetic testing.
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Redes e Vias Metabólicas/genética , Ácido Mevalônico/metabolismo , Poroceratose/genética , Carboxiliases/genética , Geraniltranstransferase/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteínas Mutantes/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/genéticaRESUMO
BACKGROUND: Melanoma is a leading cause of cancer death. Thus, accurate prognostic biomarkers that will assist rational treatment planning need to be identified. METHODS: Microarray analysis of melanoma and normal tissue samples was performed to identify differentially expressed modules (DEMs) from the signaling network and ultimately detect molecular markers to support histological examination. Network motifs were extracted from the human signaling network. Then, significant expression-correlation differential modules were identified by comparing the network module expression-correlation differential scores under normal and disease conditions using the gene expression datasets. Finally, we obtained DEMs by the Wilcoxon rank test and considered the average gene expression level in these modules as the classification features for diagnosing melanoma. RESULTS: In total, 99 functional DEMs were identified from the signaling network and gene expression profiles. The area under the curve scores for cancer module genes, melanoma module genes, and whole network modules are 92.4%, 90.44%, and 88.45%, respectively. The classification efficiency rates for nonmodule features are 71.04% and 79.38%, which correspond to the features of cancer genes and melanoma cancer genes, respectively. Finally, we acquired six significant molecular biomarkers, namely, module 10 (CALM3, Ca 2+ , PKC, PDGFRA, phospholipase-g, PIB5PA, and phosphatidylinositol-3-kinase), module 14 (SRC, Src homology 2 domain-containing [SHC], SAM68, GIT1, transcription factor-4, CBLB, GRB2, VAV2, LCK, YES, PTCH2, downstream of tyrosine kinase [DOK], and KIT), module 16 (ELK3, p85beta, SHC, ZFYVE9, TGFBR1, TGFBR2, CITED1, SH3KBP1, HCK, DOK, and KIT), module 45 (RB, CCND3, CCNA2, CDK4, and CDK6), module 75 (PCNA, CDK4, and CCND1), and module 114 (PSD93, NMDAR, and FYN). CONCLUSION: We explored the gene expression profile and signaling network in a global view and identified DEMs that can be used as diagnostic or prognostic markers for melanoma.
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Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Melanoma/genética , Transdução de Sinais/genética , Humanos , Análise em Microsséries/métodos , Transcriptoma/genéticaRESUMO
The present study was performed in order to define the clinical manifestations of porokeratosis, with particular emphasis on genital porokeratosis. A total of 55 cases of porokeratosis were retrospectively reviewed between 2000 and 2007 from Huashan Hospital (Shanghai, China). Out of 55 cases, there were 22 cases of porokeratosis of Mibelli, 17 cases of disseminated superficial actinic porokeratosis (DSAP), 15 cases of disseminated superficial porokeratosis and one case of linear porokeratosis. The ratio of males to females was 39:16. Among them, 12 cases had a family history of porokeratosis. During the five-year follow-up period, no malignant transformation was observed and no further aggravation of lesions was detected. The results indicated that the initial region of DSAP in the Chinese population may differ from Caucasians. In combination with other studies, the present study found that genital porokeratosis in the Chinese population is often associated with pruritus. Since no recurrence was observed in cases treated with surgical excision, it was suggested that surgical excision is a viable treatment strategy and should be used for porokeratotic lesions if possible. In addition, regular follow-ups are required, since the aggravation of porokeratosis may cause the development of malignancy transformation.
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BACKGROUND: Mycobacterium tuberculosis (MTB) infection has been suggested to contribute to the pathogenesis of erythema nodosum (EN) and nodular vasculitis (NV), the classic forms of panniculitis. However, there is little evidence to demonstrate the presence of MTB in the skin lesions. This study is aimed at evaluating the association between MTB infection and the development of EN and NV in a Chinese population. METHODS: A total of 107 patients (36 EN, 27 NV, and 44 others) with vasculitis and 40 control cases with other skin diseases were recruited and their skin lesion samples were subjected to real time polymerase chain reaction (PCR) analysis of the IS6110 and mpt64 gene fragments of MTB. Their blood mononuclear cells were tested for MTB antigen-specific IFN-γ responses by QuantiFERON®-TB Gold In-Tube (IT) assays. RESULTS: PCR analysis revealed that 7/23 (30.4%) and 7/18 (38.9%) of the EN and NV samples were positive for the IS6110 DNA, respectively, which were significantly higher than 3/34 (8.8%) of other vasculitis (OV) and 3/40 (7.5%) of the control samples (p<0.05). The nested Real-Time PCR assay indicated that 6/7 (86%) of the IS6110-positive EN samples, all of the IS6110-positive NV and control samples, but only 1/3 of the IS6110-positive OV samples, were positive for the mpt64 gene. Similarly, 19/32 (59.4%) of the EN patients, 20/26 (76.9%) of the NV patients, and 17/36 (47.2%) of the OV patients were positive for MTB antigen-specific IFN-γ responses, which were significantly higher than 6/40 (15%) of the controls (p<0.05). CONCLUSION: Our data strongly suggest that MTB infection and active TB are associated with the development of NV and EN in Chinese.
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Eritema Nodoso/microbiologia , Mycobacterium tuberculosis/genética , Tuberculose Cutânea/complicações , Vasculite/microbiologia , Adolescente , Adulto , Idoso , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Estudos de Casos e Controles , Criança , Feminino , Genes Bacterianos , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Reação em Cadeia da Polimerase em Tempo Real , Tuberculose Cutânea/diagnóstico , Tuberculose Cutânea/imunologia , Adulto JovemRESUMO
We report a unique case of multicentric reticulohistiocytosis (MRH) associated with liver carcinoma. A 61-year-old man presented with a 4-month history of nonpruritic, generalized, ruby-red papules and nodules, accompanied by fever, joint swelling and difficulty in swallowing. Skin histology showed polymorphic histiocyte infiltration with typical 'ground glass' cytoplasm. Further immunohistochemical studies characterized the lesions as positive for leukocyte common antigen, HLA-DR and CD68. The patient had a history of hepatitis B, and systemic examination, including carcinoma index and type-B ultrasonic examination, revealed high levels of AFP and a solid tumor, which was considered malignant, localized on the right lobe of the liver. Treatment of the liver carcinoma resulted in a significant improvement of the skin symptoms. This is the first case study to report an association between MRH and liver carcinoma. A review of the English-language literature reveals the close linkage between MRH and malignancy. All patients with MRH should be evaluated and monitored carefully to determine the underlying neoplasm.
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PURPOSE: Lymphatic invasion (LI) in primary cutaneous melanomas was recently found to be common. In this study, we evaluated LI as an independent prognostic factor. EXPERIMENTAL DESIGN: This study included 251 patients with vertical growth phase (VGP) primary cutaneous melanomas who had paraffin-fixed lesional tissue and were in a prospective cohort seen between 1972 and 1991, had no clinical evidence of regional nodal disease at diagnosis, and had at least ten years of follow-up. Dual immunohistochemical staining was used to detect lymphatic endothelium (podoplanin) and melanoma cells (S-100). Multivariate logistic regression for ten-year metastasis was used to define independent prognostic factors, and a prognostic tree was developed to characterize and discriminate risk groups. Kaplan-Meier disease-free survival curves for those with and without LI within current American Joint Committee on Cancer stages were compared using the log-rank statistic. RESULTS: LI was observed in 43% (108 of 251) of the study melanomas. The multivariate model for ten-year metastasis identified four independent prognostic factors: tumor thickness, mitotic rate, LI, and anatomic site. The prognostic tree identified a group of patients with thin (≤1 mm thick) melanomas and poor prognosis: stage IB melanomas with LI. Survival curves for time to first metastasis showed significantly poorer prognosis for patients with LI compared with those without it for both stages IB and IIA. CONCLUSIONS: LI is common across the range of tumor thicknesses in primary VGP melanomas. It is an independent prognostic factor and significantly increases the risk of metastasis in patients in clinical stages IB and IIA.