Melanocytic nevus 50524 225806509 2008-07-15T14:21:10Z RDBrown 539176 => Cite Journal with Wikipedia template filling, Pope ref to 1992 not 2006 {{Infobox_Disease | Name = Melanocytic nevus | Image = Mole (body part).jpg | Caption = Mole, more specifically an intradermal nevus | DiseasesDB = 8333 | ICD10 = {{ICD10|D|22||d|10}} | ICD9 = {{ICD9|216}} | ICDO = | OMIM = | MedlinePlus = | eMedicineSubj = derm | eMedicineTopic = 289 | MeshID = D009508 | }} A '''mole''', technically known as a '''''melanocytic [[nevus]]''''', is a small, dark spot on human [[skin]]. According to the American Academy of Dermatology, the majority of moles appear during the first two decades of a person’s life while about one in every 100 babies are born with moles{{Fact|date=April 2008}}. Acquired moles are a form of [[benign]] [[neoplasm]], while [[congenital]] moles are considered a minor [[malformation]] or [[hamartoma]]. A mole can be either subdermal (composed of [[melanin]]) or a pigmented growth on the [[skin]], formed mostly of a type of [[cell (biology)|cell]] known as a [[melanocyte]]. The high concentration of the body’s pigmenting agent, [[melanin]], is responsible for their dark [[color]]. Moles are a member of the family of [[skin]] [[lesions]] known as [[nevi]]. ==Classification== Melanocytic nevi represent a family of lesions. The most common variants are: * '''Junctional nevus''': the nevus cells are located along the junction of the [[epithelium]] and the underlying [[dermis]]. A junctional nevus is flat and brown to black. * '''Compound nevus''': a mixture of junctional and intradermal proliferation. Compound nevi are slightly raised and brown to black. [[Beauty mark]]s are usually compound nevi. * '''Intradermal nevus''': the nevus cells are located in the [[dermis]] only. Intradermal nevi are raised; most are flesh-colored (not pigmented). * '''[[Dysplastic nevus]]''' (nevus of Clark): usually a compound nevus with cellular and architectural [[dysplasia]]. They tend to be larger (more than 6 mm), with irregular borders and irregular coloration. Hence, they resemble [[melanoma]], appear worrisome and are often removed to clarify the diagnosis. Dysplastic nevi do not transform into melanoma but are a marker of risk when they are numerous ('''atypical mole syndrome'''). * '''Blue nevus''': It is blue in color as its [[melanocytes]] are very deep in the skin. The nevus cells are spindle shaped and scattered in deep layers of the [[dermis]]. The covering [[Epidermis (skin)|epidermis]] is normal. * '''Spitz nevus''': a distinct variant of intradermal nevus, usually in a child. They are raised and reddish (non-pigmented). A pigmented variant, called the '''nevus of Reed''', typically appears on the leg of young women. * '''Giant Hairy Nevus''': these large, pigmented, often hairy congenital nevi. They are important because [[melanoma]] may occasionally (10 to 15%) appear in them. * '''Intramucosal nevus''': junctional nevus of the mucosa of the mouth or genital areas. In the mouth, they are found most frequently on the hard palate. * '''Nevus of Ito''' and '''Nevus of Ota''': congenital, flat brownish lesions on the face or shoulder. * '''[[Mongolian spot]]''': congenital large, deep, bluish discoloration on the back of Asian babies. ==History== [[Image:Moles.jpg|thumb|Moles on a woman's back]] At one time in the 1950s and 60s, (and, to lesser extent, currently) a mole was known as a "[[beauty mark]]" when it appeared in certain spots on a woman’s [[face]]. Examples include [[Marilyn Monroe]], model [[Cindy Crawford]] and singer [[Madonna (Entertainer)|Madonna]]. Madonna's facial mole &ndash; below her right nostril &ndash; has been surgically removed. Almost everyone with light skin has at least one or two moles somewhere on their [[body|bodies]] while large numbers can be concentrated on the [[back]], [[chest]], and [[arm]]s. Darker skin shades, however, tend to have fewer moles. Some [[folklore]] about moles includes the [[notion]] that picking at a mole can cause it to become [[cancerous]] or grow back larger. While chronic picking or [[irritation]] (by clothing) of a mole can be detrimental in many ways, it has not been associated with a higher incidence of [[skin cancer|cancer]].<ref>{{cite journal |author=Kaskel P, Kind P, Sander S, Peter RU, Krähn G |title=Trauma and melanoma formation: a true association? |journal=Br. J. Dermatol. |volume=143 |issue=4 |pages=749–53 |year=2000 |month=October |pmid=11069451 |doi= |url=http://www.blackwell-synergy.com/openurl?genre=article&sid=nlm:pubmed&issn=0007-0963&date=2000&volume=143&issue=4&spage=749}}</ref> But while a mole may sometimes be removed by its bearer and may not grow back larger, the resulting [[scar]] can be larger. When a mole is bothersome, physicians usually recommend that it be examined by a [[dermatologist]] to see if it should be removed. The dermatologist or [[plastic surgeon]] can perform the procedure with an eye toward preventing a larger [[scar]]. {{Fact|date=June 2008}} ==Causes and prevention== ===Genes=== [[Genes]] can have an influence on a person's moles. '''[[Dysplastic nevus|Dysplastic nevi]]''' and atypical mole syndrome is a [[hereditary]] condition which causes the person to have a large quantity of moles (often 100 or more) with some larger than normal or atypical. This often leads to a higher [[risk]] of [[melanoma]], a serious [[skin cancer]].<ref>{{cite journal |author=Burkhart CG |title=Dysplastic nevus declassified: even the NIH recommends elimination of confusing terminology |journal=Skinmed |volume=2 |issue=1 |pages=12–3 |year=2003 |pmid=14673319 |doi= |url=http://www.lejacq.com/articleDetail.cfm?pid=SKINmed_2;1:12}}</ref> Dysplastic nevi are more likely than ordinary moles to become cancerous. Dysplastic nevi are common, and many people have a few of these abnormal moles. Having more than 50 ordinary moles increases the risk of developing melanoma.<ref name="ncimelanoma">{{cite web |url=http://www.nci.nih.gov/cancertopics/wyntk/melanoma/page7 |title=What You Need To Know About™ Melanoma - Melanoma: Who's at Risk? |accessdate=2008-05-18 |publisher=[[National Cancer Institute]]}}</ref> In the overall population, a slight [[majority]] of melanomas do ''not'' form in an existing mole, but rather create a new [[growth]] on the skin. Nevertheless, those with dysplastic nevi are at a higher risk of melanoma occurring not only where there is an existing mole, but surprisingly, also where there are none.<ref>{{cite journal |author=Pope DJ, Sorahan T, Marsden JR, Ball PM, Grimley RP, Peck IM |title=Benign pigmented nevi in children. Prevalence and associated factors: the West Midlands, United Kingdom Mole Study |journal=Arch Dermatol |volume=128 |issue=9 |pages=1201–6 |year=1992 |pmid=1519934 |doi= |url=}} </ref><ref>{{cite journal |author=Goldgar DE, Cannon-Albright LA, Meyer LJ, Piepkorn MW, Zone JJ, Skolnick MH |title=Inheritance of nevus number and size in melanoma and dysplastic nevus syndrome kindreds |journal=J. Natl. Cancer Inst. |volume=83 |issue=23 |pages=1726–33 |year=1991 |pmid=1770551 |doi= |url=http://jnci.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=1770551}}</ref> Such [[persons]] need to be checked regularly for any changes in their moles and to note any new ones. ===Sunlight=== [[ultraviolet light|UV radiation]] from the sun causes premature aging of the skin and skin damage that can lead to melanoma. Some scientists [[hypothesis|hypothesize]] that overexposure to UV, including excessive [[sunlight]], may play a role in the formation of acquired moles.<ref>{{cite journal |author=van Schanke A, van Venrooij GM, Jongsma MJ, ''et al'' |title=Induction of nevi and skin tumors in Ink4a/Arf Xpa knockout mice by neonatal, intermittent, or chronic UVB exposures |journal=Cancer Res. |volume=66 |issue=5 |pages=2608–15 |year=2006 |pmid=16510579 |doi=10.1158/0008-5472.CAN-05-2476 |url=http://cancerres.aacrjournals.org/cgi/pmidlookup?view=long&pmid=16510579}}</ref> However, more [[research]] is needed to determine the complex interaction between genetic makeup and overall exposure to ultraviolet light. Three strong indications that this is so (but falling short of proof), are: * The relative lack of moles on the [[buttocks]] of people with dysplastic nevi. * [[Freckle]]s (spots of melanin on the skin, and distinct from moles) are known to be influenced by sunlight. * Those born with darker skin (which better deflects UV radiation), on average, have far fewer (if any) moles. Studies have found that sunburns and too much time in the sun can increase the risk factors for melanoma. This is ''in addition to'' those who have dysplastic nevi being at higher risk of this [[cancer]]. (The uncertainty is in regard to acquiring ''benign'' moles.) To prevent and reduce the risk of melanoma caused by UV radiation, the [[American Academy of Dermatology]] and the [[National Cancer Institute]] recommends staying out of the sun between 10 a.m. and 3 p.m. standard time (or whenever your [[shadow]] is shorter than your height). The National Cancer Institute also recommends wearing long sleeves and pants, hats with a wide brim, sunscreens, and sunglasses that have UV-deflecting lenses.<ref name="ncimelanoma"/> ==Appearance== According to the [[American Academy of Dermatology]], the most common types of moles are [[skin tags]], raised moles and flat moles. Untroublesome moles are usually circular or oval and not very large. Some moles typically produce dark, coarse [[hair]]. Common mole hair removal procedures include plucking, cosmetic waxing, [[electrolysis]], [[Threading (epilation)|threading]] and cauterization. ===Differentiation from melanoma=== It often requires a dermatologist to fully evaluate moles. For instance, a small blue or bluish black spot, often called a blue nevus, is usually benign but often mistaken for melanoma.<ref>{{cite journal |author=Granter SR, McKee PH, Calonje E, Mihm MC, Busam K |title=Melanoma associated with blue nevus and melanoma mimicking cellular blue nevus: a clinicopathologic study of 10 cases on the spectrum of so-called 'malignant blue nevus' |journal=Am. J. Surg. Pathol. |volume=25 |issue=3 |pages=316–23 |year=2001 |month=March |pmid=11224601 |doi= |url=http://meta.wkhealth.com/pt/pt-core/template-journal/lwwgateway/media/landingpage.htm?issn=0147-5185&volume=25&issue=3&spage=316}}</ref> Conversely, a junctional nevus, which develops at the junction of the dermis and epidermis, is potentially cancerous.<ref>{{cite journal |author=Hall J, Perry VE |title=Tinea nigra palmaris: differentiation from malignant melanoma or junctional nevi |journal=Cutis |volume=62 |issue=1 |pages=45–6 |year=1998 |pmid=9675534 |doi= |url=}}</ref> A basic reference [[chart]] used for [[consumers]] to spot suspicious moles is found in the [[mnemonic]], A-B-C-D. The letters stand for '''A'''symmetry, '''B'''order, '''C'''olor and '''D'''iameter.<ref>{{cite web |url=http://www.nci.nih.gov/cancertopics/wyntk/melanoma/page8 |title=What You Need To Know About™ Melanoma - Signs and Symptoms |publisher=[[National Cancer Institute]] |accessdate=2008-05-18}}</ref> Sometimes, the letter E (for '''E'''levation) is added. According to the American Academy of Dermatology, if a mole starts changing in size, color, shape or, especially, if the [[border]] of a mole develops ragged edges or becomes larger than a [[pencil]] [[eraser]], it would be an appropriate time to consult with a physician. Other warning signs include a mole, even if smaller than a pencil eraser, that is different than the others and begins to crust over, bleed, [[itch]], or becomes [[inflamed]]. The changes may indicate developing [[melanomas]]. The matter can become clinically complicated because mole removal depends on which types of cancer, if any, comes into suspicion. ==Complications== Experts say that vast majority of moles are [[benign]]. Nonetheless, the U.S. [[National Cancer Institute]] estimates that 62,480 new cases of [[melanoma]] and 8,420 related deaths will appear in the United States in the year 2008.<ref>{{cite web |url=http://www.nci.nih.gov/cancertopics/types/melanoma |title=Melanoma Home Page |accessdate=2008-05-18 |publisher=[[National Cancer Institute]]}}</ref> ==Mole removal== If a mole is suspected of being a [[melanoma]], it needs to be removed and sent for microscopic evaluation by a [[pathologist]]. Other reasons for removal may be cosmetic, or because a raised mole interferes with daily life (e.g. [[shaving]]). Removal can be by [[excisional biopsy]] or by [[shaving]]. A shaved site leaves a red mark on the site which returns to the patient’s usual skin [[color]] in about two weeks. However, there might still be a risk of spread of the melanoma, so the methods of [[Melanoma#Diagnosis|Melanoma diagnosis]], including e.g. excisional biopsy {entire lump or area removed}. Moles can be removed by laser, surgery or electrocautery. In properly trained hands, some medical lasers are used to remove flat moles level with the surface of the skin, as well as some raised moles. While laser treatment is commonly offered and may require several appointments, other dermatologists think lasers are not the best method for removing moles because the laser only [[cauterization|cauterizes]] or, in certain cases, removes very [[superficial]] levels of skin. Moles tend to go deeper into the skin than non-invasive lasers can penetrate. After a laser treatment a [[scab]] is formed, which falls off about seven days later, in contrast to surgery, where the wound has to be [[suture]]d. For surgery, many dermatologic and plastic surgeons first use a freezing [[solution]], usually [[liquid nitrogen]], on a raised mole and then shave it away with a [[scalpel]]. If the surgeon opts for the shaving method, he or she usually also [[Cauterization|cauterizes]] the [[amputation|stump]]. Because a [[circle]] is difficult to close with stitches, the [[incision]] is usually [[elliptical]] or eye-shaped. [[Cauterization|Electrocautery]] is also used for removing skin tags and only reaches the outermost level of skin so that scarring is not a problem. ==See also== *[[Birthmark]] *[[Freckles]] ==References== {{reflist}} ==External links== *[http://www.mmmp.org Melanoma Molecular Map Project] *[http://www.cosmeticsurgery.com/articles/archive/an~221 Examples of moles that illustrate A-B-C-D warnings] *[http://www.nci.nih.gov/cancertopics/wyntk/moles-and-dysplastic-nevi National Cancer Institute Information on Moles] *[http://www.aad.org/public/Publications/pamphlets/Moles.htm Moles in a nutshell from the American Academy of Dermatology] [[Category:Dermatology]] [[Category:Plastic surgery]] [[de:Pigmentnävus]] [[es:lunar]] [[gd:Ball-dòbhrain]] [[it:Neo]] [[he:נקודת חן]] [[nl:Moedervlek]] [[ja:ほくろ]] [[fi:Luomi]] [[tl:Nunal]] [[vi:Nốt ruồi]] [[yi:פנים פימפל]]