Vascular structures in dermoscopy

AbstractDermoscopy is an aiding method in the visualization of the epidermis and dermis. It is usually used to diagnose melanocytic lesions. In recent years, dermoscopy has increasingly been used to diagnose non-melanocytic lesions. Certain vascular structures, their patterns of arrangement and additional criteria may demonstrate lesion-specific characteristics. In this review, vascular structures and their arrangements are discussed separately in the light of conflicting views and an overview of recent literature.

Angiogenesis in the progression of cutaneous squamous cell carcinoma: an immunohistochemical study of endothelial markers

OBJECTIVE: To demonstrate the role of angiogenesis in the progression of cutaneous squamous cell carcinoma. INTRODUCTION: Angiogenesis is a pivotal phenomenon in carcinogenesis. Its time course in cutaneous squamous cell carcinoma has not yet been fully established. METHODS: We studied the vascular bed in 29 solar keratoses, 30 superficially invasive squamous cell carcinomas and 30 invasive squamous cell carcinomas. The Chalkley method was used to quantify the microvascular area by comparing panendothelial (CD34) with neoangiogenesis (CD105) immunohistochemical markers. The vascular bed from non-neoplastic adjacent skin was evaluated in 8 solar keratoses, 10 superficially invasive squamous cell carcinomas and 10 invasive squamous cell carcinomas. RESULTS: The microvascular area in CD105-stained specimens significantly increased in parallel with cutaneous squamous cell carcinoma progression. However, no differences between groups were found in CD34 sections. Solar keratosis, superficially invasive squamous cell carcinoma and invasive squamous cell carcinoma samples showed significant increases in microvascular area for both CD34- and CD105-stained specimens compared with the respective adjacent skin. DISCUSSION: The angiogenic switch occurs early in the development of cutaneous squamous cell carcinoma, and the rate of neovascularization is parallel to tumor progression. In contrast to panendothelial markers, CD105 use allows a dynamic evaluation of tumor angiogenesis. CONCLUSION: This study demonstrated the dependence of skin carcinogenesis on angiogenesis.

Avaliação da microcirculação dos carcinomas basocelulares pela técnica de imagem espectral obtida através da polarização ortogonal / Assessment of the microcirculation of basal cell carcinomas by spectral imaging technique obtained through the orthogonal polarization

A microcirculação cutânea tem sido uma área de bastante interesse nas últimas décadas mas seu desenvolvimento tem sido reduzido pela dificuldade em desenvolver um modelo in vivo para a sua avaliação. Outra dificuldade é exercer esta avaliação em tempo real, acessando assim o próprio mecanismo etiopatogênico envolvido em diversas doenças cutâneas. O padrão-ouro no estudo da microcirculação in vivo tem sido, há anos, a microscopia intravital. Esta técnica permite uma avaliação acurada da morfologia capilar e vascular, bem como o acesso a dados da fisiologia vascular tais como a velocidade do fluxo sanguíneo, a densidade funcional capilar e a dinâmica da adesão dos leucócitos à parede vascular. A técnica de imagem espectral obtida através da polarização ortogonal (OPS - Orthogonal Polarization Spectral Imaging), recém desenvolvida, permite a avaliação in vivo da microcirculação de forma transcutânea. A observação se dá em tempo real e sem a necessidade de qualquer tipo de método invasivo por parte do examinador. Os carcinomas basocelulares são as neoplasias cutâneas mais comuns que existem. A técnica de OPS permitiu a avaliação transcutânea in vivo e demonstrou alterações estatisticamente significativas na microcirculação desses tumores.

Potential Role of Homer-2a on Cutaneous Vascular Anomaly

Homer protein was identified based on its rapid induction in rat hippocampal granule cell neurons following excitatory synaptic activity. Although the presence of the Homer gene in the peripheral tissues has been observed in previous reports, the physiological function of the Homer protein in these tissues has not been noted. In this experiment, a Homer-2a cDNA fragment was successfully amplified by RTPCR in the involuting phase of human hemangioma but not in the human vascular malformation and normal vessel. After isolation of full Homer cDNA in a mouse liver cDNA library, E1-deleted recombinant adenovirus expressing the Homer protein (Adv.CMV.mHomer-2a) was constructed to determine its physiological function in peripheral tissues. Adv.CMV.mHomer2a, but not Adv.CMV.LacZ (recombinant adenovirus expressing beta-galactosidase), strongly inhibited the growth rate of HUVECs (human umbilical vein endothelial cells) probably via inducing apoptosis determined by acridine orange/ethidium bromide (AO/EB) staining methods. This study suggests that the Homer gene is present in human specimens in the involuting phase of hemangioma, and it might be involved in the growth control.