黑色素瘤

title: 成因及诊断.
content: 对于肤色较浅的人而言,紫外线暴露是造成黑色素瘤的主因。太阳或日晒床都是可能的紫外线来源。大约有25%的黑色素瘤是从痣发展而来。有很多痣、家中曾有人得过黑色素瘤,以及免疫力低下的人,罹患黑色素瘤的风险都较高。一些罕见的基因缺陷,例如着色性干皮症,也会增加罹患的风险。诊断方法是对可疑的皮肤病变部位进行切片检查。
title: 预防与治疗.
content: 避免紫外线暴露以及使用防晒油可以预防黑色素瘤的产生。治疗方法通常是手术切除。对于黑色素瘤较大的病患,会检测邻近的淋巴结来判断是否发生转移。若没有转移的话大部分的病患可被治愈。对于黑色素瘤已发生转移的病患,免疫疗法、生物性治疗、放射线治疗或化学治疗可能可以增加存活率在美国,病患在接受治疗后,若只有局部病变五年存活率为98%,若已发生转移,五年存活率则为17%。复发或转移的可能性取决于该黑色素瘤厚度、细胞分裂速度、以及覆盖其上的皮肤是否被破坏,近年发展的免疫疗法对于该病症颇有效果,能够提高治愈率。。
title: 危害程度.
content: 黑色素瘤是皮肤癌当中最危险的一种,其恶性程度高,是皮肤癌的主要死亡原因之一。而且放射治疗与化学治疗改善程度都很有限,因此死亡率很高,若能早期诊断治疗可以提高治愈率。  2012年全球有232,000人罹患黑色素瘤,并造成55,000人死亡。澳洲和新西兰的黑色素瘤发生率为全球最高。欧洲和北美洲也有高发生率,但在亚洲、非洲和拉丁美洲,发生率则较低。在台湾则占了皮肤癌当中7%左右。男性得病的比例高于女性。1960年代以来,黑色素瘤在以白人为主的区域变得越来越常见。

Summary: 黑色素瘤,又称恶性黑色素瘤,是一种从黑色素细胞发展而来的癌症,是皮肤癌中罕见的癌症。好发于皮肤但也可能出现在口腔、肠道或眼睛中。女性患者的黑色素瘤最常出现在腿,而男性患者则最常出现在背部。有时黑色素瘤是由痣转变发展而来,有这种转变的痣外观上的改变包括尺寸变大、边缘变得不规则、颜色改变、发痒、或皮肤破坏。

Melanoma: Melanoma, also known as malignant melanoma, is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. Melanomas typically occur in the skin but may rarely occur in the mouth, intestines or eye (uveal melanoma). In women, they most commonly occur on the legs, while in men they most commonly occur on the back. About 25% of melanomas develop from moles. Changes in a mole that can indicate melanoma include an increase in size, irregular edges, change in color, itchiness or skin breakdown. The primary cause of melanoma is ultraviolet light (UV) exposure in those with low levels of the skin pigment melanin. The UV light may be from the sun or other sources, such as tanning devices. Those with many moles, a history of affected family members and poor immune function are at greater risk. A number of rare genetic conditions such as xeroderma pigmentosum also increase the risk. Diagnosis is by biopsy and analysis of any skin lesion that has signs of being potentially cancerous. Using sunscreen and avoiding UV light may prevent melanoma. Treatment is typically removal by surgery. In those with slightly larger cancers, nearby lymph nodes may be tested for spread (metastasis). Most people are cured if spread has not occurred. For those in whom melanoma has spread, immunotherapy, biologic therapy, radiation therapy or chemotherapy may improve survival. With treatment, the five-year survival rates in the United States are 99% among those with localized disease, 65% when the disease has spread to lymph nodes and 25% among those with distant spread. The likelihood that melanoma will reoccur or spread depends on its thickness, how fast the cells are dividing and whether or not the overlying skin has broken down. Melanoma is the most dangerous type of skin cancer. Globally, in 2012, it newly occurred in 232,000 people. In 2015, there were 3.1 million people with active disease, which resulted in 59,800 deaths. Australia and New Zealand have the highest rates of melanoma in the world. There are also high rates in Northern Europe and North America, while it is less common in Asia, Africa and Latin America. In the United States melanoma occurs about 1.6 times more often in men than women. Melanoma has become more common since the 1960s in areas mostly populated by people of European descent.