Distinct melanoma types based on reflectance confocal microscopy

Distinct melanoma types exist in relation to patient characteristics, tumor morphology, histopathologic aspects and genetic background. A new diagnostic imaging tool, reflectance confocal microscopy (RCM), allows in vivo analysis of a given lesion with nearly histologic resolution while offering a dynamic view of the tissue in its ‘natural’ environment. The aim of this study was to analyse cell morphology of consecutive melanomas as they appear on RCM and to correlate morphology with tumor and patient characteristics. One hundred melanomas were visualized by RCM before excision. Clinical data, confocal features and histologic criteria were analysed. Four types of melanomas were identified as follows: (i) Melanomas with a predominantly dendritic cell population (‘dendritic‐cell melanomas’) typically were thin by Breslow index; (ii) Melanomas typified by roundish melanocytes were smaller in size than dendritic cell MMs, but thicker by Breslow index, and predominantly occurred in patients with a high nevus count; (iii) Melanomas characterized by dermal nesting proliferation usually were thick by Breslow index at the time of diagnosis, although frequently smaller in size compared with the other types; and (iv) combined type melanomas may represent an evolution of dendritic cell and/or round cell types. Integration of confocal microscopy with clinical and histologic aspects may help in identifying and managing distinct tumors.     

Skin imaging with reflectance confocal microscopy

Confocal microscopy is a new imaging modality for noninvasive real-time tissue imaging with high resolution and contrast comparable with conventional histology. Application of this technology to skin imaging during the last decade has been an exciting advance in dermatology, allowing a virtual widow into living skin without the need for a conventional biopsy or histologic processing of tissue. High-resolution noninvasive skin imaging with confocal microscopy has potential broad applications in the clinical and research arenas, including differentiating between benign and malignant skin lesions, tumor margin mapping, monitoring response to medical or surgical treatments, and pathophysiologic study of inflammatory processes.     

麻风病皮损的反射式共聚焦显微镜图像特征

 目的: 探讨麻风病皮损的反射式共聚焦显微镜（RCM）图像特征,为无创辅助诊断麻风病提供新方法。方法：采用RCM检查8例麻风病患者皮损,与同处皮损的组织病理对照,分析其图像特征及意义。 结果： 与组织病理特点比对,麻风病皮损RCM图像特点为:瘤型麻风（LL）、界线类偏瘤型（BL）见表皮萎缩、角化过度、棘层萎缩,真皮浅层片、灶状“蛙籽样”组织细胞（泡沫细胞）浸润,明显可见“无浸润带”形成;界线类偏结核样型（BT）见角化过度,真皮浅层血管扩张,管周散在淋巴细胞和组织细胞浸润。结论：RCM可以作为筛查麻风病的辅助检查技术,为今后麻风病的诊断与鉴别提供新的思路和方法。     

蕈样肉芽肿在反射式共聚焦显微镜下的特征

目的 探讨临床上皮损表现为红斑鳞屑的蕈样肉芽肿在反射式共聚焦显微镜(RCM)下的特征.方法 2011年6月至2012年5月皮肤科门诊的收集蕈样肉芽肿患者6例,年龄7～73岁,病程1～5年;男4例,女2例;斑片期2例,斑块期3例,肿瘤期1例.均经组织病理和免疫组化及相关检查确诊.RCM观察6例蕈样肉芽肿患者各3处皮损,选取1处皮损行组织病理检查.结果 发现角化过度,棘层混乱,基底层色素环折光减弱,表皮内可见散在分布的单个圆形或类圆形的高折光细胞,真皮乳头环内可见少许炎细胞浸润.少数可见低折光的,圆形至椭圆形的细胞聚集形成的一个囊泡样结构.这些RCM特征与其组织病理对照有较好的一致性.结论 结合临床表现,RCM可能作为蕈样肉芽肿的无创性辅助诊断方法.     

Noninvasive imaging of melanoma with reflectance mode confocal scanning laser microscopy in a murine model

A reflectance-mode confocal scanning laser microscope (rCSLM) was developed for imaging early-stage melanoma in a living mouse model without the addition of exogenous contrast agents. Lesions were first located by surveying the dorsum with a polarized light camera, then imaged with the rCSLM. The images demonstrated two characteristics of melanoma in this animal model: (1) melanocytes and apparent tumor nests in the epidermis at the stratum spinosum in a state of pagetoid spread and (2) architectural disruption of the dermal-epidermal junction. The epidermal melanocytes and apparent tumor nests had a high melanin content, which caused their reflectance to be fivefold greater than the surrounding epidermis. The rCSLM images illustrate the difference between normal skin and sites with apparent melanoma. This imaging modality shows promise to track the progression of melanoma lesions in animal models.     

Histological classification of melasma with reflectance confocal microscopy: a pilot study in Chinese patients

Objective: To investigate the histological classification of melasma with reflectance confocal microscopy (RCM) in vivo. Methods: Two hundred and ten cases with facial melasma lesions were enrolled. After informed consent, the target melasma lesion of 10 patients were imaged with RCM and then biopsied as well. Under the RCM scanning, the distribution of the melanin determined the histological types, and then, the results of RCM images were compared with those of the histopathology. The other 200 cases were tested only with RCM. Results: For the 10 cases imaged and biopsied, compared with that of the perilesional normal skin, the amount of melanin was significantly increased in the epidermis in all lesions under RCM, while three cases also found melanin in the dermis. Thus, seven of the10 patients were categorized as the epidermal type while the other three as mixed ones, and the results were well correlated with those of the histopathology. Of the other 200 patients, 143 cases 71.5%) were categorized as the epidermal type while the other 57 (28.5%) cases as mixed ones. Limitations: If more melasma cases are biopsied, the data will be more convincing. Conclusion: RCM in vivo analysis shows complete coherence with histopathology results, which could be an alternative for the classification of melasma, and based on the results of RCM imaging, melasma is classified into two major types: the epidermal type and mixed type.