Skin cancer: Difference between revisions

| frequency = 5.6 million (2015)<!-- prevalence --><ref name=GBD2015Pre>{{cite journal | vauthors = Vos T, Allen C, Arora M, Barber RM, Bhutta ZA, Brown A, etal | title = Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990–20151990-2015: a systematic analysis for the Global Burden of Disease Study 2015 | journal = Lancet | volume = 388 | issue = 10053 | pages = 1545–1602 | date = October 2016 | pmid = 27733282 | pmc = 5055577 | doi = 10.1016/S0140-6736(16)31678-6 |doi-access=free | collaboration = GBD 2015 Disease Injury Incidence Prevalence Collaborators }}</ref>

| deaths = 111,700 (2015)<ref name=GBD2015De>{{cite journal | vauthors = Wang H, Naghavi M, Allen C, Barber RM, Bhutta ZA, Carter A, etal | title = Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–20151980-2015: a systematic analysis for the Global Burden of Disease Study 2015 | journal = Lancet | volume = 388 | issue = 10053 | pages = 1459–1544 | date = October 2016 | pmid = 27733281 | pmc = 5388903 | doi = 10.1016/s0140-6736(16)31012-1 |doi-access=free | collaboration = GBD 2015 Mortality Causes of Death Collaborators }}</ref>

'''Skin cancers''' are [[cancer]]s that arise from the [[Human skin|skin]]. They are due to the development of abnormal [[cells (biology)|cells]] that have the ability to invade or [[metastasis|spread]] to other parts of the body.<ref>{{cite web|title=Defining Cancer|url=http://www.cancer.gov/cancertopics/cancerlibrary/what-is-cancer|website=National Cancer Institute|access-date=10 June 2014|url-status=live|archive-url=https://web.archive.org/web/20140625220940/http://www.cancer.gov/cancertopics/cancerlibrary/what-is-cancer|archive-date=25 June 2014|date=17 September 2007}}</ref> Skin cancer is the most commonly diagnosed form of cancer in humans.<ref>{{cite journal | vauthors = Apalla Z, Lallas A, Sotiriou E, Lazaridou E, Ioannides D | title = Epidemiological trends in skin cancer | journal = Dermatology Practical & Conceptual | volume = 7 | issue = 2 | pages = 1–6 | date = April 2017 | pmid = 28515985 | pmc = 5424654 | doi = 10.5826/dpc.0702a01 |doi-access=free }}</ref><ref>{{cite journal | vauthors = Hu W, Fang L, Ni R, Zhang H, Pan G | title = Changing trends in the disease burden of non-melanoma skin cancer globally from 1990 to 2019 and its predicted level in 25 years | journal = BMC Cancer | volume = 22 | issue = 1 | pages = 836 | date = July 2022 | pmid = 35907848 | pmc = 9339183 | doi = 10.1186/s12885-022-09940-3 | doi-access = free }}</ref><ref>{{cite journal |last1=Lyakhov |first1=Pavel A. |last2=Lyakhova |first2=Ulyana A. |last3=Kalita |first3=Diana I. |date=2023 |title=Multimodal Analysis of Unbalanced Dermatological Data for Skin Cancer Recognition |journal=IEEE Access |volume=11 |pages=131487–131507 |doi=10.1109/ACCESS.2023.3336289 |issn=2169-3536 |quote="To date, skin cancer is the most frequently diagnosed form of oncopathology in humans and represents a wide range of malignancies. More than 40% of the total number of diagnosed cancers in the world are skin cancer."|doi-access=free }}</ref> There are three main types of skin cancers: [[basal-cell skin cancer]] (BCC), [[squamous-cell skin cancer]] (SCC) and [[melanoma]].<ref name=NCI2013TxPro>{{cite web|title=Skin Cancer Treatment (PDQ®)|url=http://www.cancer.gov/cancertopics/pdq/treatment/skin/HealthProfessional/page1/AllPages|website=NCI|access-date=30 June 2014|date=2013-10-25|url-status=live|archive-url=https://web.archive.org/web/20140705234200/http://www.cancer.gov/cancertopics/pdq/treatment/skin/HealthProfessional/page1/AllPages|archive-date=5 July 2014}}</ref> The first two, along with a number of less common skin cancers, are known as nonmelanoma skin cancer (NMSC).<ref name="Cak2012" /><ref name=ABC2008>{{cite book| vauthors = Marsden J | veditors = Rajpar S |title=ABC of skin cancer|date=2008|publisher=Blackwell Pub.|location=Malden, MA|isbn=978-1-4443-1250-8|pages=5–6|url=https://books.google.com/books?id=aRE_YuXmaFoC&pg=PA5|url-status=live|archive-url=https://web.archive.org/web/20160429172638/https://books.google.com/books?id=aRE_YuXmaFoC&pg=PA5|archive-date=29 April 2016}}</ref> Basal-cell cancer grows slowly and can damage the tissue around it but is unlikely to spread to distant areas or result in death.<ref name="Cak2012" /> It often appears as a painless raised area of skin that may be shiny with [[telangiectasia|small blood vessels running over it]] or may present as a raised area with an [[ulcer]].<ref name="NCI2013TxPro" /> Squamous-cell skin cancer is more likely to spread.<ref name="Cak2012" /> It usually presents as a hard lump with a scaly top but may also form an ulcer.<ref name=Lyn2011>{{cite book| vauthors = Dunphy LM |title=Primary Care: The Art and Science of Advanced Practice Nursing|date=2011|publisher=F.A. Davis|isbn=978-0-8036-2647-8|page=242|url=https://books.google.com/books?id=RR1hAQAAQBAJ&pg=PA242|url-status=live|archive-url=https://web.archive.org/web/20160520044442/https://books.google.com/books?id=RR1hAQAAQBAJ&pg=PA242|archive-date=20 May 2016}}</ref> Melanomas are the most aggressive. Signs include a [[melanocytic nevus|mole]] that has changed in size, shape, color, has irregular edges, has more than one color, is itchy or bleeds.<ref name=Mel2014>{{cite web|title=General Information About Melanoma|url=http://www.cancer.gov/cancertopics/pdq/treatment/melanoma/Patient/page1/AllPages|website=NCI|access-date=30 June 2014|date=2014-04-17|url-status=live|archive-url=https://web.archive.org/web/20140705115020/http://www.cancer.gov/cancertopics/pdq/treatment/melanoma/Patient/page1/AllPages|archive-date=5 July 2014}}</ref>

More than 90% of cases are caused by exposure to [[ultraviolet radiation]] from the [[Sun]].<ref name=UV2010>{{cite journal | vauthors = Gallagher RP, Lee TK, Bajdik CD, Borugian M | title = Ultraviolet radiation | journal = Chronic Diseases in Canada | volume = 29 | issue = Suppl 1 | pages = 51–68 | date = 2010 | pmid = 21199599 | doi = 10.24095/hpcdp.29.S1.04 | pmid doi-access= 21199599free }}</ref> This exposure increases the risk of all three main types of skin cancer.<ref name="UV2010" /> Exposure has increased, partly due to a thinner [[ozone layer]].<ref name="Cak2012" /><ref>{{cite journal | vauthors = Maverakis E, Miyamura Y, Bowen MP, Correa G, Ono Y, Goodarzi H | title = Light, including ultraviolet | journal = Journal of Autoimmunity | volume = 34 | issue = 3 | pages = J247-57J247–J257 | date = May 2010 | pmid = 20018479 | pmc = 2835849 | doi = 10.1016/j.jaut.2009.11.011 }}</ref> [[Tanning beds]] are another common source of ultraviolet radiation.<ref name="UV2010" /> For melanomas and basal-cell cancers, exposure during childhood is particularly harmful.<ref name="WCR2014" /> For squamous-cell skin cancers, total exposure, irrespective of when it occurs, is more important.<ref name="UV2010" /> Between 20% and 30% of melanomas develop from moles.<ref name="WCR2014" /> People with lighter skin are at higher risk<ref name="NCI2013TxPro" /><ref>{{cite journalbook | vauthors = Leiter U, Garbe C | title = Sunlight, Vitamin D and Skin Cancer | chapter = Epidemiology of melanomaMelanoma and nonmelanomaNonmelanoma skinSkin cancer--theCancer—The roleRole of sunlightSunlight | journalseries = Advances in Experimental Medicine and Biology | volume = 624 | pages = 89–103 | date = 2008 | pmid = 18348450 | doi = 10.1007/978-0-387-77574-6_8 |doi-access=free | isbn = 978-0-387-77573-9 }}</ref> as are those with poor immune function such as from medications or [[HIV/AIDS]].<ref name="Cak2012" /><ref>{{cite journal | vauthors = Chiao EY, Krown SE | title = Update on non-acquired immunodeficiency syndrome-defining malignancies | journal = Current Opinion in Oncology | volume = 15 | issue = 5 | pages = 389–97389–397 | date = September 2003 | pmid = 12960522 | doi = 10.1097/00001622-200309000-00008 | s2cid = 33259363 }}</ref> Diagnosis is by [[biopsy]].<ref name="Mel2014" />

Decreasing exposure to ultraviolet radiation and the use of [[sunscreen]] appear to be effective methods of preventing melanoma and squamous-cell skin cancer.<ref name="WCR2014" /><ref name=Jou2012>{{cite journal | vauthors = Jou PC, Feldman RJ, Tomecki KJ | title = UV protection and sunscreens: what to tell patients | journal = Cleveland Clinic Journal of Medicine | volume = 79 | issue = 6 | pages = 427–36427–436 | date = June 2012 | pmid = 22660875 | doi = 10.3949/ccjm.79a.11110 | doi-access = free }}</ref> It is not clear if sunscreen affects the risk of basal-cell cancer.<ref name="Jou2012" /> Nonmelanoma skin cancer is usually curable.<ref name="Cak2012" /> Treatment is generally by surgical removal but may, less commonly, involve [[radiation therapy]] or topical medications such as [[fluorouracil]].<ref name="NCI2013TxPro" /> Treatment of melanoma may involve some combination of surgery, [[chemotherapy]], [[radiation therapy]] and [[targeted therapy]].<ref name="Mel2014" /> In those people whose disease has spread to other areas of the body, [[palliative care]] may be used to improve quality of life.<ref name="Mel2014" /> 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 [[Five-year survival rate|surviving more than 5 years]].<ref>{{cite web|title=SEER Stat Fact Sheets: Melanoma of the Skin|url=http://seer.cancer.gov/statfacts/html/melan.html|website=NCI|access-date=18 June 2014|url-status=live|archive-url=https://web.archive.org/web/20140706134347/http://seer.cancer.gov/statfacts/html/melan.html|archive-date=6 July 2014}}</ref><ref>{{cite web|title=Release: Cancer Survival Rates, Cancer Survival in England, Patients Diagnosed 2005–2009 and Followed up to 2010|url=http://www.ons.gov.uk/ons/publications/re-reference-tables.html?edition=tcm%3A77-239726|website=Office for National Statistics|access-date=30 June 2014|date=15 November 2011|url-status=live|archive-url=https://web.archive.org/web/20141017061743/http://www.ons.gov.uk/ons/publications/re-reference-tables.html?edition=tcm%3A77-239726|archive-date=17 October 2014}}</ref>

Skin cancer is the most common form of cancer, globally accounting for at least 40% of cancer cases.<ref name=Cak2012>{{cite journal | vauthors = Cakir BÖ, Adamson P, Cingi C | title = Epidemiology and economic burden of nonmelanoma skin cancer | journal = Facial Plastic Surgery Clinics of North America | volume = 20 | issue = 4 | pages = 419–22419–422 | date = November 2012 | pmid = 23084294 | doi = 10.1016/j.fsc.2012.07.004 }}</ref><ref>{{cite journal | vauthors = Dubas LE, Ingraffea A | title = Nonmelanoma skin cancer | journal = Facial Plastic Surgery Clinics of North America | volume = 21 | issue = 1 | pages = 43–53 | date = February 2013 | pmid = 23369588 | doi = 10.1016/j.fsc.2012.10.003 }}</ref> The most common type is nonmelanoma skin cancer, which occurs in at least 2–3 million people per year.<ref name="WCR2014" /><ref>{{cite web|title=How common is skin cancer?|url=https://www.who.int/uv/faq/skincancer/en/index1.html|website=World Health Organization|access-date=30 June 2014|url-status=live|archive-url=https://web.archive.org/web/20100927065836/http://www.who.int/uv/faq/skincancer/en/index1.html|archive-date=27 September 2010}}</ref> This is a rough estimate, however, as; good statistics are not kept.<ref name="NCI2013TxPro" /> Of nonmelanoma skin cancers, about 80% are basal-cell cancers and 20% squamous-cell skin cancers.<ref name="ABC2008" /> Basal-cell and squamous-cell skin cancers rarely result in death.<ref name="WCR2014" /> In the United States, they were the cause of less than 0.1% of all cancer deaths.<ref name="NCI2013TxPro" /> Globally in 2012, melanoma occurred in 232,000 people and resulted in 55,000 deaths.<ref name="WCR2014" /> White people in [[Australia]], [[New Zealand]] and [[South Africa]] have the highest rates of melanoma in the world.<ref name="WCR2014" /><ref>{{cite book | vauthors = Harris RE | title=Epidemiology of Chronic Disease |date=2013 |publisher=Jones & Bartlett Publishers |isbn=978-0-7637-8047-0 |page=271 |url=https://books.google.com/books?id=KJLEIvX4wzoC&pg=PA271 }}</ref> The three main types of skin cancer have become more common in the last 20 to 40 years, especially regions where the population is predominantly White.<ref name="Cak2012" /><ref name=WCR2014>{{cite book|title=World Cancer Report 2014.|date=2014|publisher=World Health Organization|isbn=978-9283204299|pages=Chapter 5.14}}</ref>

BCC and SCC often carry a UV-signature mutation indicating that these cancers are caused by [[UVB]] radiation via direct DNA damage. However malignant melanoma is predominantly caused by UVA radiation via indirect DNA damage. The indirect DNA damage is caused by free radicals and reactive oxygen species. Research indicates that the absorption of three sunscreen ingredients into the skin, combined with a 60-minute exposure to UV, leads to an increase of [[free radicals]] in the skin, if applied in too little quantity and too infrequently.<ref name="Hanson">{{cite journal | vauthors = Hanson KM, Gratton E, Bardeen CJ | title = Sunscreen enhancement of UV-induced reactive oxygen species in the skin | journal = Free Radical Biology & Medicine | volume = 41 | issue = 8 | pages = 1205–121205–1212 | date = October 2006 | pmid = 17015167 | doi = 10.1016/j.freeradbiomed.2006.06.011 | s2cid = 13999532 | url = https://escholarship.org/content/qt9f14s2dd/qt9f14s2dd.pdf?t=oe9hj9 }}</ref> However, the researchers add that newer creams often do not contain these specific compounds, and that the combination of other ingredients tends to retain the compounds on the surface of the skin. They also add that frequent re-application reduces the risk of radical formation.

There are a variety of different skin cancer symptoms. These include changes in the [[Human skin|skin]] that do not heal, [[Ulcer (dermatology)|ulcering]] in the skin, discolored skin, and changes in existing [[Mole (skin marking)|moles]], such as jagged edges to the mole, enlargement of the mole, changes in color, the way it feels or if it bleeds. Other common signs of skin cancer can be painful lesion that itches or burns and large brownish spot with darker speckles.<ref>Mayo Clinic (2020). Skin Cancer: Symptoms and Causes. https://www.mayoclinic.org/diseases-conditions/skin-cancer/symptoms-causes/syc-20377605</ref>

Basal-cell skin cancer (BCC) usually presents as a raised, smooth, pearly bump on the sun-exposed skin of the [[Human head|head]], [[neck]], [[torso]] or [[shoulder]]s. Sometimes small [[blood vessel]]s (called [[telangiectasia]]) can be seen within the tumor. Crusting and bleeding in the center of the tumor frequently develops. It is often mistaken for a sore that does not heal. This form of skin cancer is the least deadly, and with proper treatment can be eliminated, often without significant scarring.

Most melanoma consist of various colours from shades of brown to black. A small number of melanoma are pink, red or fleshy in colour; these are called amelanotic melanoma and tend to be more aggressive. Warning signs of malignant melanoma include change in the size, shape, color or elevation of a mole. Other signs are the appearance of a new mole during adulthood or pain, itching, ulceration, redness around the site, or bleeding at the site. An often-used mnemonic is "ABCDE", where A is for "asymmetrical", B for "borders" (irregular: "Coast of Maine sign"), C for "color" (variegated), D for "diameter" (larger than 6&nbsp;mm – the size of a pencil eraser) and E for "evolving."<ref>{{Citecite web|url = http://www.cancer.gov/cancertopics/wyntk/skin.pdf|title = What You Need To Know About: Melanoma and Other Skin Cancers|publisher = National Cancer Institute|url-status = live|archive-url = https://web.archive.org/web/20130318041656/http://www.cancer.gov/cancertopics/wyntk/skin.pdf|archive-date = 18 March 2013}}</ref><ref>{{Citecite web|url = http://www.cancer.org/acs/groups/cid/documents/webcontent/003120-pdf.pdf|title = Melanoma Skin Cancer|publisher = American Cancer Society|year = 2012|url-status = live|archive-url = https://web.archive.org/web/20130909230623/http://www.cancer.org/acs/groups/cid/documents/webcontent/003120-pdf.pdf|archive-date = 9 September 2013}}</ref>

Ultraviolet radiation from sun exposure is the primary environmental cause of skin cancer.<ref>{{cite journal | vauthors = Narayanan DL, Saladi RN, Fox JL | title = Ultraviolet radiation and skin cancer | journal = International Journal of Dermatology | volume = 49 | issue = 9 | pages = 978–86978–986 | date = September 2010 | pmid = 20883261 | doi = 10.1111/j.1365-4632.2010.04474.x | s2cid = 22224492 | doi-access = free }}</ref><ref name=Review05>{{cite journal | vauthors = Saladi RN, Persaud AN | title = The causes of skin cancer: a comprehensive review | journal = Drugs of Today | volume = 41 | issue = 1 | pages = 37–53 | date = January 2005 | pmid = 15753968 | doi = 10.1358/dot.2005.41.1.875777 }}</ref><ref>{{cite journal | vauthors = Gordon R | title = Skin cancer: an overview of epidemiology and risk factors | journal = Seminars in Oncology Nursing | volume = 29 | issue = 3 | pages = 160–9160–169 | date = August 2013 | pmid = 23958214 | doi = 10.1016/j.soncn.2013.06.002 }}</ref><ref>{{cite journal |last1 vauthors = Mata |first1=DouglasDA, A. |last2=Williams |first2=ErikEA, A. |last3=Sokol |first3=EthanE, |last4=Oxnard |first4=Geoffrey R.GR, |last5=Fleischmann |first5=ZoeZ, |last6=Tse |first6=JulieJY, Y.Decker |last7=DeckerB |first7=Brennan |title = Prevalence of UV Mutational Signatures Among Cutaneous Primary Tumors | journal = JAMA Network Open |date=23 March 2022 |volume = 5 | issue = 3 | pages = e223833 | date = March 2022 | pmid = 35319765 | pmc = 8943639 | doi = 10.1001/jamanetworkopen.2022.3833 |pmid=35319765|pmc=8943639 |s2cid = 247616874 }}</ref> This can occur in professions such as farming. Other risk factors that play a role include:

* The use of many [[immunosuppressive drug|immunosuppressive]] medications increases the risk of skin cancer.<ref>{{cite journal | vauthors = Roche CD, Dobson JS, Williams SK, Quante M, ChowPopoola J, Chow JW | title = Malignant and Noninvasivenoninvasive Skinskin Tumourstumours in Renalrenal Transplanttransplant Recipientsrecipients | journal = Dermatology Research and Practice | volume = 409058 | date = 2014 | pagepages = 409058 | doidate = 10.1155/2014/409058 | pmid = 25302063 | pmc = 4180396 | doi = 10.1155/2014/409058 | doi-access = free }}</ref> [[Cyclosporin A]], a [[calcineurin inhibitor]] for example increases the risk approximately 200 times, and [[azathioprine]] about 60 times.<ref>{{cite journal | vauthors = Kuschal C, Thoms KM, Schubert S, Schäfer A, Boeckmann L, Schön MP, Emmert S | title = Skin cancer in organ transplant recipients: effects of immunosuppressive medications on DNA repair | journal = Experimental Dermatology | volume = 21 | issue = 1 | pages = 2–6 | date = January 2012 | pmid = 22151386 | doi = 10.1111/j.1600-0625.2011.01413.x | s2cid = 25776283 | doi-access = free }}</ref>

* Deliberate exposure of sensitive skin not normally exposed to sunlight during [[wellness (alternative medicine)|alternative wellness]] behaviors such as [[perineum sunning]] sunning.

[[ultraviolet|UV-irradiation]] of skin cells causes [[DNA damage (naturally occurring)|damage to DNA]] through [[photochemistry|photochemical reactions]].<ref name="lee">{{cite journal | vauthors = Lee JW, Ratnakumar K, Hung KF, Rokunohe D, Kawasumi M | title = Deciphering UV-induced DNA Damage Responses to Prevent and Treat Skin Cancer | journal = Photochemistry and Photobiology | volume = 96 | issue = 3 | pages = 478–499 | date = May 2020 | pmid = 32119110 | pmc = 7651136 | doi = 10.1111/php.13245 |url=}}</ref> Cyclobutane [[pyrimidine dimer]]s formed by adjacent thymine bases, or by adjacent cytosine bases, are frequent types of DNA damage induced by UV.<ref name=lee/> Human skin cells are capable of repairing most UV-induced damage by [[nucleotide excision repair]], a process that protects against skin cancer, but may be inadequate at high levels of exposure.<ref name=lee/>

Non-invasive skin cancer detection methods include photography, dermatoscopy, sonography, [[confocal microscopy]], Raman spectroscopy, fluorescence spectroscopy, terahertz spectroscopy, optical coherence tomography, the multispectral imaging technique, thermography, electrical bio-impedance, tape stripping and computer-aided analysis.<ref>{{Citecite journal | vauthors = Narayanamurthy V, Padmapriya P, Noorasafrin A, Pooja B, Hema K, Firus Khan AY, Nithyakalyani K, Samsuri F |date display-authors =2018 6 | title = Skin cancer detection using non-invasive techniques | journal = RSC Advances | volume = 8 | issue = 49 | pages = 28095–28130 |doi date =10.1039/c8ra04164d August 2018 | pmid = 35542700 | pmc = 9084287 |bibcode doi =2018RSCAd 10...828095N1039/c8ra04164d | doi-access = free | bibcode = 2018RSCAd...828095N }}</ref>

Dermatoscopy may be useful in diagnosing basal cell carcinoma in addition to skin inspection.<ref>{{cite journal | vauthors = Dinnes J, Deeks JJ, Chuchu N, Matin RN, Wong KY, Aldridge RB, Durack A, Gulati A, Chan SA, Johnston L, Bayliss SE, Leonardi-Bee J, Takwoingi Y, Davenport C, O'Sullivan C, Tehrani H, Williams HC | display-authors = 6 | title = Visual inspection and dermoscopy, alone or in combination, for diagnosing keratinocyte skin cancers in adults | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | pagesissue = CD01190112 | datepages = December 2018CD011901 | issuedate = 12December 2018 | pmid = 30521688 | pmc = 6516870 | doi = 10.1002/14651858.CD011901.pub2 | collaboration = Cochrane Skin Group }}</ref>

There is insufficient evidence that optical coherence tomography (OCT) is useful in diagnosing melanoma or squamous cell carcinoma. OCT may have a role in diagnosing basal cell carcinoma but more data is needed to support this.<ref>{{cite journal | vauthors = Ferrante di Ruffano L, Dinnes J, Deeks JJ, Chuchu N, Bayliss SE, Davenport C, Takwoingi Y, Godfrey K, O'Sullivan C, Matin RN, Tehrani H, Williams HC | display-authors = 6 | title = Optical coherence tomography for diagnosing skin cancer in adults | journal = The Cochrane Database of Systematic Reviews | volume = 12 | pagesissue = CD01318912 | datepages = December 2018CD013189 | issuedate = 12December 2018 | pmid = 30521690 | pmc = 6516952 | doi = 10.1002/14651858.CD013189 | collaboration = Cochrane Skin Group }}</ref>

Computer-assisted diagnosis devices have been developed that analyze images from a [[dermatoscopy|dermatoscope]] or spectroscopy and can be used by a diagnostician to aid in the detection of skin cancer. CAD systems have been found to be highly sensitive in the detection of melanoma, but have a high false-positive rate. There is not yet enough evidence to recommend CAD as compared to traditional diagnostic methods.<ref>{{cite journal | vauthors = Ferrante di Ruffano L, Takwoingi Y, Dinnes J, Chuchu N, Bayliss SE, Davenport C, Matin RN, Godfrey K, O'Sullivan C, Gulati A, Chan SA, Durack A, O'Connell S, Gardiner MD, Bamber J, Deeks JJ, Williams HC | display-authors = 6 | title = Computer-assisted diagnosis techniques (dermoscopy and spectroscopy-based) for diagnosing skin cancer in adults | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | pagesissue = CD01318612 | datepages = December 2018CD013186 | issuedate = 12December 2018 | pmid = 30521691 | pmc = 6517147 | doi = 10.1002/14651858.cd013186 }}</ref>

[[High-frequency ultrasound]] (HFUS) is of unclear usefulness in the diagnosis of skin cancer.<ref>{{cite journal | vauthors = Dinnes J, Bamber J, Chuchu N, Bayliss SE, Takwoingi Y, Davenport C, Godfrey K, O'Sullivan C, Matin RN, Deeks JJ, Williams HC | display-authors = 6 | title = High-frequency ultrasound for diagnosing skin cancer in adults | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | pagesissue = CD01318812 | datepages = December 2018CD013188 | issuedate = 12December 2018 | pmid = 30521683 | pmc = 6516989 | doi = 10.1002/14651858.cd013188 }}</ref> There is insufficient evidence for reflectance confocal microscopy to diagnose basal cell or squamous cell carcinoma or any other skin cancers.<ref>{{cite journal | vauthors = Dinnes J, Deeks JJ, Chuchu N, Saleh D, Bayliss SE, Takwoingi Y, Davenport C, Patel L, Matin RN, O'Sullivan C, Patalay R, Williams HC | display-authors = 6 | title = Reflectance confocal microscopy for diagnosing keratinocyte skin cancers in adults | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | pagesissue = CD01319112 | datepages = December 2018CD013191 | issuedate = 12December 2018 | pmid = 30521687 | pmc = 6516892 | doi = 10.1002/14651858.CD013191 | collaboration = Cochrane Skin Group }}</ref>

[[Sunscreen]] is effective and thus recommended to prevent melanoma<ref name=SunM>{{cite journal | vauthors = Kanavy HE, Gerstenblith MR | title = Ultraviolet radiation and melanoma | journal = Seminars in Cutaneous Medicine and Surgery | volume = 30 | issue = 4 | pages = 222–8222–228 | date = December 2011 | pmid = 22123420 | doi = 10.1016/j.sder.2011.08.003 }}</ref> and squamous-cell carcinoma.<ref name=SunS>{{cite journal | vauthors = Burnett ME, Wang SQ | title = Current sunscreen controversies: a critical review | journal = Photodermatology, Photoimmunology & Photomedicine | volume = 27 | issue = 2 | pages = 58–67 | date = April 2011 | pmid = 21392107 | doi = 10.1111/j.1600-0781.2011.00557.x | s2cid = 29173997 | doi-access = }}</ref> There is little evidence that it is effective in preventing basal-cell carcinoma.<ref>{{cite journal | vauthors = Kütting B, Drexler H | title = UV-induced skin cancer at workplace and evidence-based prevention | journal = International Archives of Occupational and Environmental Health | volume = 83 | issue = 8 | pages = 843–54843–854 | date = December 2010 | pmid = 20414668 | doi = 10.1007/s00420-010-0532-4 | s2cid = 40870536 | bibcode = 2010IAOEH..83..843K }}</ref> Other advice to reduce rates of skin cancer includes avoiding sunburn, wearing protective clothing, sunglasses and hats, and attempting to avoid sun exposure or periods of peak exposure.<ref>{{cite journal | vauthors = Balk SJ | title = Ultraviolet radiation: a hazard to children and adolescents | journal = Pediatrics | volume = 127 | issue = 3 | pages = 588–97588–597 | date = March 2011 | pmid = 21357336 | doi = 10.1542/peds.2010-3501 | s2cid = 24739322 | doi-access = }}</ref> The [[U.S. Preventive Services Task Force]] recommends that people between 9 and 25 years of age be advised to avoid ultraviolet light.<ref name="Behavioral counseling to prevent sk">{{cite journal | vauthors = Lin JS, Eder M, Weinmann S | title = Behavioral counseling to prevent skin cancer: a systematic review for the U.S. Preventive Services Task Force | journal = Annals of Internal Medicine | volume = 154 | issue = 3 | pages = 190–201 | date = February 2011 | pmid = 21282699 | doi = 10.7326/0003-4819-154-3-201102010-00009 | s2cid = 13796237 | citeseerx = 10.1.1.690.6405 | s2cid = 13796237 }}</ref>

The reason itIt is important to limit sun exposure and to avoid tanning beds is, because they both involve UV light. UV light is known to damage skin cells by mutating thetheir DNA in it. The mutated DNA can cause tumors and other growths to form on the skin. Further, there are other risk factors beside just UV exposure. Fair skin, prolonged history of sunburns, moles, and family history of skin cancer are just a few.<ref>{{cite web |url=https://www.mayoclinic.org/diseases-conditions/skin-cancer/symptoms-causes/syc-20377605 |website=Mayo Clinic|title=Skin cancer – Symptoms and causes}}</ref>

There is insufficient evidence either for or against screening for skin cancers.<ref>{{cite journal | vauthors = Bibbins-Domingo K, Grossman DC, Curry SJ, Davidson KW, Ebell M, Epling JW, García FA, Gillman MW, Kemper AR, Krist AH, Kurth AE, Landefeld CS, Mangione CM, Phillips WR, Phipps MG, Pignone MP, Siu AL | display-authors = 6 | title = Screening for Skin Cancer: US Preventive Services Task Force Recommendation Statement | journal = JAMA | volume = 316 | issue = 4 | pages = 429–35429–435 | date = July 2016 | pmid = 27458948 | doi = 10.1001/jama.2016.8465 | doi-access = free }}</ref> [[Vitamin supplements]] and [[antioxidant supplements]] have not been found to have an effect in prevention.<ref>{{cite journal | vauthors = Chang YJ, Myung SK, Chung ST, Kim Y, Lee EH, Jeon YJ, Park CH, Seo HG, Huh BY | display-authors = 6 | title = Effects of vitamin treatment or supplements with purported antioxidant properties on skin cancer prevention: a meta-analysis of randomized controlled trials | journal = Dermatology | volume = 223 | issue = 1 | pages = 36–44 | year = 2011 | pmid = 21846961 | doi = 10.1159/000329439 | s2cid = 12333832 }}</ref> Evidence for reducing melanoma risk from dietary measures is tentative, with some supportive epidemiological evidence, but no clinical trials.<ref>{{cite journal | vauthors = Jensen JD, Wing GJ, Dellavalle RP | title = Nutrition and melanoma prevention | journal = Clinics in Dermatology | volume = 28 | issue = 6 | pages = 644–9644–649 | date = November–December 2010 | pmid = 21034988 | doi = 10.1016/j.clindermatol.2010.03.026 }}</ref>

[[Zinc oxide]] and [[titanium oxide]] are often used in sunscreen to provide broad protection from UVA and UVB ranges.<ref>{{cite journal | vauthors = Smijs TG, Pavel S | title = Titanium dioxide and zinc oxide nanoparticles in sunscreens: focus on their safety and effectiveness | journal = Nanotechnology, Science and Applications | volume = 4 | pages = 95–112 | date = October 2011 | pmid = 24198489 | pmc = 3781714 | doi = 10.2147/NSA.S19419 | doi-access = free }}</ref>

Eating certain foods may decrease the risk of sunburns but this is much less than the protection provided by sunscreen.<ref>{{cite journal | vauthors = Stahl W, Sies H | title = β-Carotene and other carotenoids in protection from sunlight | journal = The American Journal of Clinical Nutrition | volume = 96 | issue = 5 | pages = 1179S–84S1179S–1184S | date = November 2012 | pmid = 23053552 | doi = 10.3945/ajcn.112.034819 | doi-access = free }}</ref>

A meta-analysis of skin cancer prevention in high risk individuals found evidence that topical application of T4N5 liposome lotion reduced the rate of appearance of basal cell carcinomas in people with [[xeroderma pigmentosum]], and that [[acitretin]] taken by mouth may have a skin protective benefit in people following [[kidney transplant]].<ref>{{cite journal | vauthors = Bath-Hextall F, Leonardi-Bee J, Somchand N, Webster A, Delitt J, Perkins W | title = Interventions for preventing non-melanoma skin cancers in high-risk groups | journal = The Cochrane Database of Systematic Reviews | issue = 4 | pages = CD005414 | date = October 2007 | volume = 2015 | pmid = 17943854 | doi = 10.1002/14651858.CD005414.pub2 | urlpmc = http://www.cochrane.org/CD005414/SKIN_interventions-for-preventing-of-non-melanoma-skin-cancers-in-high-risk-groups10799667 | hdl-access = 2123/22258free | hdl-access = free2123/22258 }}</ref>

A researchpaper published in January 2022 by the Oregon State University College of Pharmacy showed that a vaccine that stimulates the production of a protein critical to the skin's antioxidant network could reinforce people's defenses against skin cancer.<ref>{{Citecite web|title=Possibility of vaccine to prevent skin cancer|url=https://www.sciencedaily.com/releases/2022/01/220112093811.htm|access-date=2022-01-16|website=ScienceDaily|language=en}}</ref>

For low-risk disease, radiation therapy ([[external beam radiotherapy]]<ref>{{cite journal | vauthors = Hill R, Healy B, Holloway L, Kuncic Z, Thwaites D, Baldock C | title = Advances in kilovoltage x-ray beam dosimetry | journal = Physics in Medicine and Biology | volume = 59 | issue = 6 | pages = R183-231R183–R231 | date = March 2014 | pmid = 24584183 | doi = 10.1088/0031-9155/59/6/r183 | s2cid = 18082594 | bibcode = 2014PMB....59R.183H | s2cid = 18082594 }}</ref> or [[brachytherapy]]), topical chemotherapy ([[imiquimod]] or 5-fluorouracil) and cryotherapy (freezing the cancer off) can provide adequate control of the disease; all of them, however, may have lower overall cure rates than certain type of surgery. Other modalities of treatment such as photodynamic therapy, [[epidermal radioisotope therapy]],<ref>{{cite book | vauthors = Cipriani C, Sedda AF | chapter = Epidermal Radionuclide Therapy: Dermatological High-Dose-Rate Brachytherapy for the Treatment of Basal and Squamous Cell Carcinoma |date=2012| chapter-url=http://link.springer.com/10.1007/174_2012_778| title = Therapeutic Nuclear Medicine| series = Medical Radiology |pages=725–734| veditors = Baum RP |place=Berlin, Heidelberg |publisher=Springer Berlin Heidelberg|doi=10.1007/174_2012_778|isbn=978-3-540-36718-5|access-date=2021-01-15}}</ref> topical chemotherapy, [[electrodesiccation and curettage]] can be found in the discussions of [[basal-cell carcinoma]] and [[squamous-cell carcinoma]].

Treatments for metastatic melanoma include biologic immunotherapy agents [[ipilimumab]], [[pembrolizumab]], [[nivolumab]], [[cemiplimab]]; [[BRAF inhibitor]]s, such as [[vemurafenib]] and [[dabrafenib]]; and a [[MEK inhibitor]] [[trametinib]].<ref>{{cite journal | vauthors = Maverakis E, Cornelius LA, Bowen GM, Phan T, Patel FB, Fitzmaurice S, He Y, Burrall B, Duong C, Kloxin AM, Sultani H, Wilken R, Martinez SR, Patel F | display-authors = 6 | title = Metastatic melanoma –- a review of current and future treatment options | journal = Acta Dermato-Venereologica | volume = 95 | issue = 5 | pages = 516–24516–524 | date = May 2015 | pmid = 25520039 | doi = 10.2340/00015555-2035 | url = http://digitalcommons.wustl.edu/cgi/viewcontent.cgi?article=4849&context=open_access_pubs | doi-access = free }}</ref>

Local skin flaps are a method of closing defects with tissue that closely matches the defect in color and quality. Skin from the periphery of the defect site is mobilized and repositioned to fill the deficit. Various forms of local flaps can be designed to minimize disruption to surrounding tissues and maximize cosmetic outcome of the reconstruction. Pedicled skin flaps are a method of transferring skin with an intact blood supply from a nearby region of the body. An example of such reconstruction is a pedicled forehead flap for the repair of a large nasal skin defect. Once the flap develops a source of blood supply form its new bed, the vascular pedicle can be detached.<ref>[{{cite web | url = http://facedoctornyc.com/cancer-reconstruction.php | title = Skin Cancer Reconstruction] {{webarchive| work = FaceDoctorNYC.com | archive-url = https://archive.today/20110710215630/http://facedoctornyc.com/cancer-reconstruction.php | archive-date = 10 July 2011 }}</ref>

The mortality rate of basal-cell and squamous-cell carcinoma is around 0.3%, causing 2000 deaths per year in the US. In comparison, the mortality rate of melanoma is 15–20% and it causes 6500 deaths per year.<ref name=BoringCC>{{cite journal | vauthors = Boring CC, Squires TS, Tong T | title = Cancer statistics, 1991 | journal = CA: A Cancer Journal for Clinicians | volume = 41 | issue = 1 | pages = 19–36 | year = 1991 | pmid = 1984806 | doi = 10.3322/canjclin.41.1.19 | s2cid = 40987916 | doi-access = free }}</ref>{{rp|29,31}} Even though it is much less common, malignant melanoma is responsible for 75% of all skin cancer-related deaths.<ref name=AAFP>{{cite journal | vauthors = Jerant AF, Johnson JT, Sheridan CD, Caffrey TJ | title = Early detection and treatment of skin cancer | journal = American Family Physician | volume = 62 | issue = 2 | pages = 357–68, 375–6, 381–2 | date = July 2000 | pmid = 10929700 | url = http://www.aafp.org/afp/20000715/357.html | url-status = live | archive-url = https://web.archive.org/web/20080724153613/http://www.aafp.org/afp/20000715/357.html | archive-date = 24 July 2008 }}</ref>

The survival rate for people with melanoma depends upon when they start treatment. The cure rate is very high when melanoma is detected in early stages, when it can easily be removed surgically. The prognosis is less favorable if the melanoma has spread to other parts of the [[Human body|body]].<ref>{{cite web|url=http://www.skincancerjournal.com/melanoma/|title=Malignant Melanoma Cancer | work = Skin Cancer Journal | date = 2009 |access-date=2010-07-02|url-status=live|archive-url=https://web.archive.org/web/20100323064318/http://www.skincancerjournal.com/melanoma/|archive-date=23 March 2010}}</ref> As of 2003 the overall five-year cure rate with Mohs' micrographic surgery was around 95 percent for recurrent basal cell carcinoma.<ref>{{cite journal | vauthors = Wong CS, Strange RC, Lear JT | title = Basal cell carcinoma | journal = BMJ | volume = 327 | issue = 7418 | pages = 794–8794–798 | date = October 2003 | pmid = 14525881 | pmc = 214105 | doi = 10.1136/bmj.327.7418.794 }}</ref>

[[Australia]] and [[New Zealand]] exhibit one of the highest rates of skin cancer incidence in the world, almost four times the rates registered in the United States, the [[UK]] and [[Canada]]. Around 434,000 people receive treatment for non-melanoma skin cancers and 10,300 are treated for melanoma. Melanoma is the most common type of cancer in people between 15 and 44 years in both countries. The incidence of skin cancer has been increasing.<ref>{{cite web |url= http://www.cancer.org.au/cancersmartlifestyle/SunSmart/Skincancerfactsandfigures.htm |title=Skin Cancer Facts and Figures | date = 3 May 2012 | work = Cancer Council Australia |access-date=2013-12-01|quote=From 1982 to 2007 melanoma diagnoses increased by around 50%. From 1998 to 2007, GP consultations to treat non-melanoma skin cancer increased by 14%, to reach 950,000 visits each year.|url-status=live|archive-url=https://web.archive.org/web/20120810071104/http://www.cancer.org.au/cancersmartlifestyle/SunSmart/Skincancerfactsandfigures.htm|archive-date=10 August 2012}}</ref> The incidence of melanoma among [[Auckland]] residents of European descent in 1995 was 77.7 cases per 100,000 people per year, and was predicted to increase in the 21st century because of "the effect of local stratospheric ozone depletion and the time lag from sun exposure to melanoma development."<ref>{{cite journal | vauthors = Jones WO, Harman CR, Ng AK, Shaw JH | title = Incidence of malignant melanoma in Auckland, New Zealand: highest rates in the world | journal = World Journal of Surgery | volume = 23 | issue = 7 | pages = 732–5732–735 | date = July 1999 | pmid = 10390596 | doi = 10.1007/pl00012378 | s2cid = 11995057 | url = http://www.kmc.co.nz/ViewArticle.aspx?id=32744 | url-status = dead | s2cid = 11995057 | archive-url = https://web.archive.org/web/20131203031716/http://www.kmc.co.nz/ViewArticle.aspx?id=32744 | archive-date = 3 December 2013 }}</ref>

Skin cancers result in 80,000 deaths a year as of 2010, 49,000 of which are due to melanoma and 31,000 of which are due to non-melanoma skin cancers.<ref name=Loz2012>{{cite journal | vauthors = Lozano R, Naghavi M, Foreman K, Lim S, Shibuya K, Aboyans V, etal | title = Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010 | journal = Lancet | volume = 380 | issue = 9859 | pages = 2095–1282095–2128 | date = December 2012 | pmid = 23245604 | doi = 10.1016/S0140-6736(12)61728-0 | urlpmc = http://dro.deakin.edu.au/eserv/DU:30050819/ortblad-globalandregional-2012.pdf10790329 | hdl-access = 10536/DRO/DU:30050819free | s2cid = 1541253 | hdl-access = free10536/DRO/DU:30050819 | url = https://zenodo.org/record/2557786 }}</ref> This is up from 51,000 in 1990.<ref name="Loz2012" />

In the US in 2008, 59,695 people were diagnosed with melanoma, and 8,623 people died from it.<ref name="cdc.gov">[{{cite web | url = https://www.cdc.gov/cancer/skin/statistics/index.htm CDC| –work Skin= CancerU.S. Statistics<!--Centers Botfor generatedDisease Control and Prevention (CDC) | title -->]= Skin Cancer Statistics {{webarchive| archive-url = https://web.archive.org/web/20120908062143/http://www.cdc.gov/cancer/skin/statistics/index.htm | archive-date = 8 September 2012 }}</ref> In Australia more than 12,500 new cases of melanoma are reported each year, out of which more than 1,500 die from the disease. Australia has the highest per capita incidence of melanoma in the world.<ref>{{cite web | title = Melanoma facts and statistics | work = Melanoma Institute Australia |url=http://www.melanoma.org.au/about-melanoma/melanoma-skin-cancer-facts.html |access-date=2014-05-18 |url-status=dead |archive-url=https://web.archive.org/web/20140518185825/http://www.melanoma.org.au/about-melanoma/melanoma-skin-cancer-facts.html |archive-date=18 May 2014}}</ref>

Approximately 2,000 people die from basal or squamous cell skin cancers (non-melanoma skin cancers) in the United States each year. The rate has dropped in recent years. Most of the deaths happen to people who are elderly and might not have seen a doctor until the cancer had spread; and people with immune system disorders.<ref name=":0">{{Citecite web|url=http://www.cancer.org/cancer/skincancer-basalandsquamouscell/detailedguide/skin-cancer-basal-and-squamous-cell-key-statistics|title=Key statistics for basal and squamous cell skin cancers|website=www.cancer.org|publisher=American Cancer Society|access-date=2017-01-09|url-status=live|archive-url=https://web.archive.org/web/20170110103347/http://www.cancer.org/cancer/skincancer-basalandsquamouscell/detailedguide/skin-cancer-basal-and-squamous-cell-key-statistics|archive-date=10 January 2017}}</ref>

* [http://www.oncolex.org/en/Skin-cancer Skin cancer procedures: text, images and videos] {{Webarchive|url=https://web.archive.org/web/20131207034706/http://www.oncolex.org/en/Skin-cancer |date=7 December 2013 }}