醫週譯：Skin cancer/皮膚癌
'''皮膚癌'''是一種生長在皮膚上，可能有多種原因造成的[[癌]]。最常見的3種皮膚癌是[[基底細胞癌]]、[[鱗狀細胞癌]]和[[黑色素瘤]]。由於皮膚癌常常在[[表皮]]層中發展，腫瘤常常清晰可見，因此大部分時間，可以在早期發現皮膚癌。 與包括[[肺癌]]、[[胰腺癌]]、[[胃癌]]在內的大多數癌症不同，因皮膚癌死亡的人數很少[16]. 皮膚癌是最常見的癌症，超過了肺癌，乳房，結腸直腸癌，前列腺癌[16] 。與基底細胞癌、鱗狀細胞癌比較，黑色素瘤較為少見，但是更為嚴重，在英國，截止至2009年，平均每年有9,500人罹患此病，2,300人死亡[17]。在20歲到30歲的人群中，黑色素瘤是最常見的癌症之一[18]， 多由長時間的太陽照射造成[19]。
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Skin cancers are cancers that arise from the skin. They are due to the development of abnormal cells that have the ability to invade or spread to other parts of the body.[1] There are three main types: basal cell cancer (BCC), squamous cell cancer (SCC) andmelanoma.[2] The first two together along with a number of less common skin cancers are known as nonmelanoma skin cancer (NMSC).[3][4] Basal cell cancer grows slowly and can damage the tissue around it but is unlikely to spread to distant areas or result in death.[3] It often appears as a painless raised area of skin, that may be shiny with small blood vessel running over it or may present as a raised area with an ulcer.[2] Squamous cell cancer is more likely to spread.[3] It usually presents as a hard lump with a scaly top but may also form an ulcer.[5] Melanomas are the most aggressive. Signs include a mole that has changed in size, shape, color, has irregular edges, has more than one color, is itchy or bleeds.[6]
<!-- 定義與症狀 -->
'''皮膚癌'''是一種生長在[[皮膚]]上的癌症，它是由異常的[[細胞]]發展而來，甚至有可能會侵犯擴散到身體不同部位[1]。由於皮膚癌常常在[[表皮]]層中發展，腫瘤常常清晰可見，因此大部分時間，可以在早期發現皮膚癌。 與包括[[肺癌]]、[[胰腺癌]]、[[胃癌]]在內的大多數癌症不同，因皮膚癌死亡的人數很少[16]。皮膚癌是最常見的癌症，超過了肺癌、乳房、結腸直腸癌，前列腺癌[16] 。最常見的3種皮膚癌是{{Link-en|基底細胞癌（BCC）|Basal-cell_carcinoma}}、[[鱗狀細胞癌]]（SCC）和[[黑色素瘤]][2]。前二者和其他較少見的皮膚癌被稱作非黑色素瘤皮膚癌（NMSC）[3][4]。基底細胞癌生長速度慢，且可能破壞周圍組織，但較不會遠端轉移或致死[3]；通常皮膚上出現以無痛突起的區塊，表面發亮{{link-en|微血管擴張|Telangiectasia|伴隨著小血管}}，或是於突起處有{{link-en|潰瘍|Ulcer (dermatology)}}[2]。鱗狀細胞癌則較基底細胞癌容易轉移[3]，通常呈現具鱗狀表皮的硬塊，但也可能以潰瘍形式表現[5]。與基底細胞癌、鱗狀細胞癌比較，黑色素瘤較為少見，但是黑色素瘤是當中表現最為惡性的，可能的徵象包括[[黑素細胞痣|痣]]的大小、形狀、顏色發生改變，痣的邊緣不規則，顏色不均勻，可能會癢或是流血[6]。
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Greater than 90% of cases are caused by exposure to ultraviolet radiation from the sun.[7] This exposure increases the risk of all three main types of skin cancer.[7] Exposure has increased partly due to a thinner ozone layer.[3] Tanning beds are becoming another common source of ultraviolet radiation.[7] For melanomas and basal cell cancers exposure during childhood is particularly harmful.[8] For squamous cell cancers total exposure, irrespective of when it occurs, is more important.[7] Between 20% and 30% of melanomas develop from moles.[8] People with light skin are at higher risk [2] as are those with poor immune function such as from medications or HIV/AIDS.[3][9] Diagnosis is by biopsy.[6]
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超過九成的皮膚癌案例是由於暴露在太陽光[[紫外線]]而造成的[7]，而這樣的暴露會增加罹患上述三種主要皮膚癌的風險[7]。[[臭氧層]]漸薄可能是導致暴露增加的原因[3]；而[[日晒床|日曬機]]是近年來另一項常見的紫外線來源[7]。以黑色素瘤和基底細胞癌來說，童年時期的暴露特別有害[8]；而以鱗狀細胞癌來說，總暴露量較暴露的時期更關鍵[7]。二到三成的黑色素瘤是由痣發展而來[8]。膚色較白的人[2]、免疫系統功能不佳的人，如接受特定藥物、人類免疫缺乏病毒感染者或[[愛滋病]]患者[3][9]，有較高的罹病風險。皮膚癌必須經由[[活體組織切片|切片]]診斷[6]。
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Decreasing exposure to ultraviolet radiation and the use of sunscreen appears to be effective methods of preventing melanoma and squamous cell cancer.[8][10] It is not clear if sunscreen affects the risk of basal cell cancer.[10] Nonmelanoma skin cancer is usually curable.[3] Treatment is generally by surgical removal but may less commonly involve radiation therapy or topical medications such as fluorouracil.[2] Treatment of melanoma may involve some combination of surgery, chemotherapy, radiation therapy, and targeted therapy.[6] In those people whose disease has spread to other areas of their bodies, palliative care may be used to improve quality of life.[6] Melanoma has one of the higher survival rates among cancers, with over 86% of people in the UK and more than 90% in the United States surviving more than 5 years.[11][12]
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減少紫外線的暴露，並且使用[[防曬油]]是預防黑色素瘤及鱗狀細胞癌最有效的方法[8][10]，但目前對於防曬油的使用對基底細胞癌的影響還不清楚[10]。非黑色素瘤皮膚癌通常都是可治癒的[3]。治療主要是透過手術切除，還有較不常見的[[放射線療法]]或是局部藥物如[[5-氟尿嘧啶|氟尿嘧啶]][2]。黑色素瘤的治療則會牽涉到手術、[[化學治療]]、放射線治療以及[[標靶治療]]的組合[6]。而那些發生遠端轉移的病患，[[临终关怀|緩和醫療]]可能有助於改善生活品質[6]。罹患黑色素瘤的存活率在所有癌症當中較高，在英國[[五年存活率]]可達86%，在美國可達90%[11][12]。
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Skin cancer is the most common form of cancer, globally accounting for at least 40% of cases.[3][13] It is especially common among people with light skin.[14] The most common type is nonmelanoma skin cancer, which occurs in at least 2-3 million people per year.[8][15] This is a rough estimate, however, as good statistics are not kept.[2] Of nonmelanoma skin cancers, about 80% are basal cell cancers and 20% squamous cell cancers.[4] Basal cell and squamous cell cancers rarely result in death.[8] In the United States they were the cause of less than 0.1% of all cancer deaths.[2] Globally in 2012 melanoma occurred in 232,000 people, and resulted in 55,000 deaths.[8] Australia and New Zealand have the highest rates of melanoma in the world.[8] The three main types of skin cancer have become more common in the last 20 to 40 years, especially in those areas which are mostlyCaucasian.[3][8]
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皮膚癌是最常見的癌症形式，全球來說佔了癌症總數的四成[3][13]。它尤其常見於膚色較淺的人們[14]。最常見的類型為非黑色素瘤，每年約新增2至3百萬人罹病[8][15]。這是粗估計的數值，由於較精細的數據並未被持續追蹤[2]。在非黑色素瘤當中，約有八成屬於{{Link-en|基底細胞癌|Basal-cell_carcinoma}}，而其中兩成屬於[[鱗狀細胞癌]]。在英國，截止至2009年，平均每年有9,500人罹患此病，2,300人死亡[17]。在20歲到30歲的人群中，黑色素瘤是最常見的癌症之一[18]， 多由長時間的太陽照射造成[19]。這兩種癌症鮮少造成死亡案例，在美國這兩種癌症造成的死亡案例佔癌症死亡總數的0.1%以下[2]。全球案例顯示2012年共新增23.2萬起黑色素瘤案例，而黑色素瘤在當年共造成5.5萬起死亡案例[8]。澳洲及紐西蘭有全球最高的黑色素瘤致死率[8]。在過去20到40年這三種類型的皮膚癌發生率變得更高，尤其在那些以[[白人]]為主的國家[3][8]。