Moles

views updated May 23 2018

Moles

Definition

A mole (nevus) is a pigmented (colored) spot on the outer layer of the skin (epidermis).

Description

Moles can be round, oval, flat, or raised. They can occur singly or in clusters on any part of the body. Most moles are brown, but colors can range from pinkish flesh tones to yellow, dark blue, or black.

Everyone has at least a few moles. They generally appear by the time a person is 20 and resemble freckles at first. A mole's color and shape don't usually change. Changes in hormone levels that occur during puberty and pregnancy can make moles larger and darker. New moles may also appear during this period.

A mole usually lasts about 50 years before beginning to fade. Some moles disappear completely, and some never lighten at all. Some moles develop stalks that raise them above the skin's surface; these moles eventually drop off.

Types of moles

About 1-3% of all babies have one or more moles when they are born. Moles that are present at birth are called congenital nevi.

Other types of moles include:

  • Junctional moles, which are usually brown and may be flat or slightly raised.
  • Compound moles, which are slightly raised, range in color from tan to dark brown, and involve pigment-producing cells (melanocytes) in both the upper and lower layers of the skin (epidermis and dermis).
  • Dermal moles, which range from flesh-color to brown, are elevated, most common on the upper body, and may contain hairs.
  • Sebaceous moles, which are produced by over-active oil glands and are yellow and rough-textured.
  • Blue moles, which are slightly raised, colored by pigment deep within the skin, and most common on the head, neck, and arms of women.

Most moles are benign, but atypical moles (dysplastic nevi) may develop into malignant melanoma, a potentially fatal form of skin cancer. Atypical moles are usually hereditary. Most are bigger than a pencil eraser, and the shape and pigmentation are irregular.

Congenital nevi are more apt to become cancerous than moles that develop after birth, especially if they are more than eight inches in diameter. Lentigo maligna (melanotic freckle of Hutchinson), most common on the face and after the age of 50, first appears as a flat spot containing two or more shades of tan. It gradually becomes larger and darker. One in three of these moles develop into a form of skin cancer known as lentigo maligna melanoma.

Causes and symptoms

The cause of moles is unknown, although atypical moles seem to run in families and result from exposure to sunlight.

In the past several years, researchers have identified two genes known as CDKN2A and CDK4 that govern susceptibility to melanoma in humans. Other susceptibility genes are being sought as of early 2003. Most experts, however, think that these susceptibility genes are not sufficient by themselves to account for moles becoming cancerous but are influenced by a combination of other inherited traits and environmental factors.

Diagnosis

Only a small percentage of moles require medical attention. A mole that has the following symptoms should be evaluated by a dermatologist (a physician spealizing in skin diseases).

  • Appears after the age of 20
  • Bleeds
  • Itches
  • Looks unusual or changes in any way.

A doctor who suspects skin cancer will remove all or part of the mole for microscopic examination. This procedure, which is usually performed in a doctor's office, is simple, relatively painless, and does not take more than a few minutes. It does leave a scar.

The doctor may also use a dermatoscope to examine the mole prior to removal. The dermatoscope, which can be used to distinguish between benign moles and melanomas, is an instrument that resembles an ophthalmoscope. An immersion oil is first applied to the mole to make the outer layers of skin transparent.

A combination of high-frequency ultrasound and color Doppler studies has also been shown to have a high degree of accuracy in distinguishing between melanomas and benign moles.

Treatment

If laboratory analysis confirms that a mole is cancerous, the dermatologist will remove the rest of the mole. Patients should realize that slicing off a section of a malignant mole will not cause the cancer to spread.

Removing a mole for cosmetic reasons involves numbing the area and using scissors or a scalpel to remove the elevated portion. The patient is left with a flat mole the same color as the original growth. Cutting out parts of the mole above and beneath the surface of the skin can leave a scar more noticeable than the mole.

Scissors or a razor can be used to temporarily remove hair from a mole. Permanent hair removal, however, requires electrolysis or surgical removal of the mole.

Prognosis

Moles are rarely cancerous and, once removed, unlikely to recur. A dermatologist should be consulted if a mole reappears after being removed.

Prevention

Wearing a sunscreen and limiting sun exposure may prevent some moles. Anyone who has moles should examine them every month and see a dermatologist if changes in size, shape, color, or texture occur or if new moles appear.

A team of researchers at Duke University reported in 2003 that topical application of a combination of 15% vitamin C and 1% vitamin E over a four-day period offered significant protection against sunburn. The researchers suggest that this combination may protect skin against aging caused by sunlight as well.

Anyone with a family history of melanoma should see a dermatologist for an annual skin examination. Everyone should know the ABCDEs of melanoma:

  • A: Asymmetry, which occurs when the two halves of the mole are not identical
  • B: Borders that are irregular or indistinct
  • C: Color that varies in a single mole
  • D: Diameter, which should be no larger than a pencil eraser (about 6 mm)
  • E: Elevated above the surrounding tissue.

KEY TERMS

Dermatology The branch of medicine that studies and treats disorders of the skin.

Malignant melanoma A potentially fatal form of skin cancer that develops from melanocytes, which are skin cells containing melanin.

Melanin A dark insoluble pigment found in humans in the skin, hair, choroid layer of the eye, and a part of the brain called the substantia nigra.

Nevus (plural, nevi) The medical term for any anomaly of the skin that is present at birth, including moles and birthmarks.

A mole with any of these characteristics should be evaluated by a dermatologist.

Advances in photographic technique have now made it easier to track the development of moles with the help of whole-body photographs. A growing number of hospitals are offering these photographs as part of outpatient mole-monitoring services.

Resources

BOOKS

Beers, Mark H., MD, and Robert Berkow, MD, editors. "Dermatologic Disorders: Malignant Tumors." Section 10, Chapter 126. In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.

Beers, Mark H., MD, and Robert Berkow, MD, editors. "Dermatologic Disorders: Moles." Section 10, Chapter 125. In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.

Beers, Mark H., MD, and Robert Berkow, MD, editors. "Dermatologic Disorders: Reactions to Sunlight." Section 10, Chapter 119. In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.

PERIODICALS

Bennett, D. C. "Human Melanocyte Senescence and Melanoma Susceptibility Genes." Oncogene 22 (May 19, 2003): 3063-3069.

Bessoud, B., N. Lassau, S. Koscielny, et al. "High-Frequency Sonography and Color Doppler in the Management of Pigmented Skin Lesions." Ultra sound in Medicine & Biology 6 (June 2003): 875-879.

Bray, C. "The Development of an Improved Method of Photography for Mole-Monitoring at the University Hospital of North Durham." Journal of Audiovisual Media in Medicine 26 (June 2003): 60-66.

Hall, Daniel J., MD, and Michael Holtel, MD. "Malignant Melanoma of the Face and Neck." eMedicine July 3, 2003. http://www.emedecine.com.ent/topic27.htm.

Lin, J. Y., M. A. Selim, C. R. Shea, et al. "UV Photoprotection by Combination Topical Antioxidants Vitamin C and Vitamin E." Journal of the American Academy of Dermatology 48 (June 2003): 866-874.

Tucker, M. A., and A. M. Goldstein. "Melanoma Etiology: Where Are We?" Oncogene 22 (May 19, 2003): 3042-3052.

ORGANIZATIONS

American Academy of Dermatology. 930 N. Meacham Road, P.O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. Fax: (847) 330-0050. http://www.aad.org.

American Cancer Society. 1599 Clifton Road NE, Atlanta, GA 30329. (800) ACS-2345.

National Cancer Institute (NCI). NCI Public Inquiries Office, Suite 3036A, 6116 Executive Boulevard, MSC8332, Bethesda, MD 20892-8322. (800) 4-CANCER or (800) 332-8615 (TTY). http://www.nci.nih.gov.

Nevus Outreach, Inc. 1601 Madison Blvd., Bartesville, OK 74006. (877) 426-3887. http://www.nevus.org.

Moles

views updated May 17 2018

Moles

Desmans

Golden moles

Resources

Moles are small burrowing animals of the order Insectivora, mammals with teeth designed for crushing the outer shells of insects. The true moles and desmans (water-living moles) make up the family Talpidae, which inhabit most of North America and northern Eurasia. The similar golden moles of Africa, south of the Sahara, make up the family Chrysochloridae.

Moles vary from 1-3 in (24-75 mm) in length, plus a pink, naked tail that may be equally long, but is usually short. An adult male weighs more than 3.5 oz (100 g) and adult females less than that. A mole must eat its own weight in food each day or die, because its body has no fat preservation system.

Moles are thoroughly adapted for a life of digging. They have streamlined bodies, with nothing that might interfere with burrowing. Their front feet appear to come straight out of their bodies and are angled outward so that as they dig through soil, using first one hand, then the other, they appear to be swimming the breaststroke. Their flexible snouts are also used in digging, and their similarly tapered hind ends can easily move through soil. Unlike most mammals, whose hair lies toward the back of the body, a moles fur can lie equally well in either direction as the animal moves in either direction. The fur is very soft.

Their functioning eyes reveal only light and dark. Instead they rely primarily on their senses of smell and touch. The surface of the muzzle is covered with thousands of tiny sensory organs that allow it to analyze even the most delicate touch. These organs, called Eimers organs, identify food and digging sites. Their faces and forelimbs are also covered with special sensory hairs, called vibrissae.

The presence of moles is generally revealed by the presence of mounds of loosened soil called molehills. As they burrow, they toss the soil backward, and it eventually piles up on the surface. Surface burrows, which are visible from above, are dug in newly turned farm fields and very light soil, where the worms and other invertebrates the moles eat are near the top. Deep burrows, the digging of which produce molehills, are dug in heavier, drier soil where the invertebrates have moved downward to find moisture. These deep burrows may last many years and even many generations. They need to be rebuilt only if accidentally damaged. A mole marks a tunnel as its territory by giving off a strong odor from its scent gland. If the scent wears off and is not refreshed by the animal perhaps because it has fallen prey to an owlother animals may move into the burrow.

A moles entire life centers around its burrow. Certain areas of a moles burrow are used to store food, such as earthworms that have had their heads bitten off. In the center of the burrow is a nest lined with grasses and other dry material, such as scraps of

paper hauled in from the surface. Every mole sleeps in its nest, but a female also raises her young in it until they have been weaned.

Moles breed in early spring, and two to eight 2-in-long (50-mm) young are born in late spring. They are born blind, hairless, and red-colored, weighing about 0.1 oz (3.5 g). They are out on their own by early fall. Though many die during their migration to find their own burrowing grounds, moles often live for six or seven years. They are capable of breeding when they are about a year old.

The nose of the strange star-nosed mole (Condylura cristata ) of eastern North America is divided into 22 rubbery lobes, or tentacles, that make the black-furred animal look as if it has a pink flower on its nose. Each tentacle is covered with a large number of Eimers organs. The star-nosed mole also has an unusual tail. Longer than most the tails of most moles, it acts as a fat-storage organ during the breeding season. These are the only moles that live in pairs, with the male helping to raise the young. Their fur is waterproof, which lets them dig into saturated soil, as well as swim in search of tiny crustaceans to eat.

The little American shrew-mole (Neurotrichus gibbsii ) of the West Coast looks like a mole but has fur more like a shrews, which doesnt change direction. This is the smallest American mole, averaging only 2.5-3 in (6-7 cm) in body length. Oddly enough, its closest relative lives straight across the Pacific in Japan. Shrew-moles, though they burrow like other moles, leave their shallow burrows to search for food among the litter on a forest floor.

The common, or eastern, American mole is Scalopus aquaticus. Despite its webbed back feet and its scientific name, the common American mole is not a water-living animal. It has the widest range of any American mole, from Mexico to New England to Florida. Other western moles of California include the broad-footed mole (Scapanus latimanus ), the coast mole (S. orarius ), and Townsends mole (S. townsendii ).

There are about 13 species of Old World moles, all in genus Talpa. The European mole (T. europaea ) resides in most of Europe and over into central Russia. European moles have been known to turn their molehills into mountains, or at least fortresses, by building quite large structures above ground. Fortresses are found only in areas that flood regularly.

Moles dont eat bulbs of flowering plants as many gardeners who have watched their flowers die believe. Instead, other creatures such as meadow mice move into mole burrows, from which they can reach those succulent plant parts. Moles are now generally left alone except on golf courses. Their very soft skins were often collected at the end of the nineteenth century for use in high-quality clothing.

Desmans

The two species of desmans make up a separate subfamily from the true moles. One (Galemys pyrenaicus ) lives in the Pyrenees, the other (Desmana moschata ) in Russia, both by fast-flowing rivers. Desmans are swimmers. They swim with the aid of a flattened, rudderlike tail, powerful legs, and long back feet. Their fingers and toes are also webbed.

Desmans are much larger than moles, sometimes reaching 16 in (41 cm) including their tails. Their long, flexible snouts contain nostrils that can be closed tightly against the water by special valves. Their ears can also be closed. Their fur is especially soft, and the Russian desman has long been killed for its marketable fur. Two or more desmans will share their burrows, located in the banks of a river.

Golden moles

The family of golden moles is made up of about 20 species that live in Africa, south of the Sahara. They are not necessarily golden in color, though they do often have a colorful, lustrous sheen to their coats. They are tailless and, unlike true moles, blind. They are born with the remnants of useless eyes, which develop hairy coverings as they mature. The end of a golden moles nose is leathery to aid in burrowing through the soil, though the primary digging is done by heavy, sharp claws.

Grants desert golden mole (Eremitalpa granti ) of the Namib Desert has only dry sand to dig through. Its meandering burrow collapses behind it as it continually digs. Only if rain has fallen recently does the burrow hold its shape for any length of time. Other golden moles live in moister places where their burrows hold their shape.

The large golden moles of South Africa (Chrysospalax ) do not rely solely on ground invertebrates for food. They go to the surface at night to feed, hunting especially for giant worms. The surface may bring danger, however, and a golden mole that finds itself in danger may collapse dramatically, pretending to be dead. The Cape golden mole of Uganda (Chrysochloris stuhlmanni ) lives at fairly high altitudes, up to 10,000 ft (3,050 m).

Resources

BOOKS

Bailey, Jill. Discovering Shrews, Moles & Voles. New York: The Bookwright Press, 1989.

Caras, Roger A. North American Mammals: Fur-Bearing Animals of the United States and Canada. New York: Meredith Press, 1967.

Gorman, Martyn L., and R. David Stone. The Natural History of Moles. Ithaca, NY: Comstock Publishing Associates, 1990.

Nowak, Ronald M. Walkers Mammals of the World. 6th ed. Baltimore: The Johns Hopkins University Press, 1999.

Jean F. Blashfield

Moles

views updated May 14 2018

Moles

JUDSON KNIGHT

A mole is a high-ranking intelligence officer for one agency who covertly feeds information to a rival or enemy agency. In practice, the difference between a mole and an agent-inplacean employee of one intelligence agency who, of his or her own initiative, offers services to a rival or enemy agencyis a murky one, and seems to involve distinctions of rank. Moles are usually individuals who carry considerable authority within the agencies that employ them, and thus, the information they provide to their secondary employer is likely to be of high caliber.

In order to discuss examples of moles, it is necessary to draw distinctions between these and other categories of spy. Because high rank is usually regarded as a characteristic of a mole, most enlisted military personnel, such as the Marine guards at the U.S. embassy in Moscow during the 1980s, who were literally seduced into spying by attractive female KGB operatives, did not serve as moles, even though the intelligence they provided may have aided the services that used them as agents.

Furthermore, because moles are usually intelligence officers currently employed by the agency against which they are spying, the definition does not encompass all

members of the infamous Walker family spy ring, several of whom had retired from the U.S. Navy before they began spying for the Soviet Union. Most important, a mole is actively engaged in the covert collection and transfer of intelligence, meaning that inactive or sleeper agents, who are simply awaiting instructions before beginning work, do not qualify as moles.

Soviet and Russian Moles

In the superpower conflict between the Soviet Union and the United States during the Cold War, and between the United States and the Russian Federation in the years since, there have been many more known cases of moles employed by the Soviets and Russians than by the Americans. This is most likely not a result of American failure to use moles as extensively; rather, unless they were caught, the identities of moles friendly to the United States are unlikely to be exposed until many years after the fact.

Among the most infamous Soviet moles in the West was the Cambridge spy ring, whose members included Harold (Kim) Philby, Donald Maclean, Guy Burgess, John Cairncross, Anthony Blunt, and others. Recruited at Britain's Cambridge University in the 1930s, these were scions of the privileged classes who had become disillusioned with the system that had fostered them. Beginning with Blunt, they readily provided information against their own nation and its allies, and recruited others to do so.

The members of the Cambridge spy ring for the most part, refused to accept pay for their deeds. This was not only because most of them came from wealthy backgrounds, but also because they genuinely considered that spying for the Soviet Union served an idealistic purpose. Actions of the Cambridge ring cost many lives, either directly or indirectly, and many of those identified by them died in situations involving torture. In the end, several members of the ring, including its leader Kim Philby, crossed the Iron Curtain and spent the remainder of their days under the care of their Soviet sponsors.

Ideology and money. In the ideologically charged atmosphere of the 1930s, and among an elite class such as that of the Cambridge spy ring, it was possible for the Soviets to find agents willing to serve as moles for ideological reasons and not for profit. By the end of World War II and the beginning of the Cold War, however, the pattern had changed: rather than ideology, money had become the principal motivating factor for most moles, who provided mostly technical rather than strategic information to their Soviet handlers.

From the standpoint of the Soviets, this later crop of moles was more reliable than the Cambridge ring and other ideological spies of the 1930s. A spy motivated by ideology fancies himself to be acting on moral principle alone, and thus, free to resist orders that he finds objectionable. By contrast, an individual so driven by greed that he will literally sell human lives for money is not likely to judge any job too dirty if the price is right.

Such was the case with Aldrich Ames of the Central Intelligence Agency (CIA), who provided the Soviets and later the Russians with information for nine years. At the time of his arrest in 1994, he was driving a late model red XJ6 Jaguar, just one of many items he had purchased with the $2.7 million his handlers paid him over the course of the preceding decade. Much the same was the case with Robert Hanssen, a Federal Bureau of Intelligence counterintelligence special agent who served as a mole for the Soviets and Russians prior to his arrest in 2001.

A plethora of moles. The Cambridge ring and the two paid moles of the 1990s are just a few among many examples of Soviet and later Russian infiltration directed against the United States or the West in general. In 1963, it was discovered that French diplomat George Pâques had been collecting intelligence on the North Atlantic Treaty Organization (NATO) and passing it on to the Soviets. Three years later, U.S. authorities arrested William Whelan, an army lieutenant colonel who served as intelligence advisor to the army chief of staff.

During this period, CIA counterespionage chief James Jesus Angleton spent considerable energy and resources on uncovering moles. During the late 1960s and early 1970s, Angleton conducted an aggressive "molehunt" in which more than 120 CIA agents came under suspicion. Quarrels with CIA chief William Colby led to Angleton's dismissal in 1974. Yet, Angleton was not always inaccurate in his judgments; virtually from the moment he met Philby, an officer in British intelligence, he expressed suspicions that Philby was a molean assessment borne out by subsequent discoveries.

U.S. and British Moles

The most well known mole for the West was Oleg Penkovsky, a colonel in the KGB. From the late 1940s, Penkovsky served the Soviet regime faithfully, but he became increasingly disillusioned with Communism in general and Premier Nikita Khrushchev in particular. Assigned to set up a KGB network while operating under the cover of a trade delegation, he first attempted to contact U.S. authorities, who initially refused to accept that the high-ranking officer would willingly provide them with secrets. Frustrated, Penkovsky offered his services to British intelligence through businessman Greville Wynne in 1961.

Wynne arranged a meeting with British intelligence in London, and thereafter Penkovsky supplied valuable information to both British and American authorities. Over an 18-month period, he delivered more than 5,000 photo-graphs, as well as other information on Soviet military strength, war plans, missiles, and satellite systems. In the Cuban Missile Crisis of October 1962, President John F. Kennedy would make extensive use of information provided by Penkovsky. Afterward, the Soviets, aware that they had a mole in their midst, conducted a molehunt of their own. Several days after Penkovsky was tried and convicted in a 1963 show trial, he was executed by the KGB.

Another U.S. mole working in the Communist Bloc was Michael Goleniewski, a Polish military intelligence officer who passed secrets to the CIA before defecting to the West in 1960. Less fortunate was the case of Anatoly Filatov, caught in a CIA sex entrapment scheme in Algiers in 1976. Confronted with the threat of compromising revelations, Filatov agreed to provide the CIA with intelligence from the Soviet foreign ministry. Apprehended by the Soviets in 1978, he met the same fate as Penkovsky before him.

FURTHER READING:

BOOKS:

Buranelli, Vincent, and Nan Buranelli. Spy Counterspy: An Encyclopedia of Espionage. New York: McGraw-Hill, 1982.

Hood, William. Mole. New York: Norton, 1982.

Nash, Jay Robert. Spies: A Narrative Encyclopedia of Dirty Deeds and Double Dealing from Biblical Times to Today. New York: M. Evans, 1997.

Polmar, Norman, and Thomas B. Allen. Spy Book: The Encyclopedia of Espionage. New York: Random House, 1998.

Vise, David A. The Bureau and the Mole: The Unmasking of Robert Philip Hanssen, the Most Dangerous Double Agent in FBI History. New York: Atlantic Monthly Press, 2002.

West, Nigel. Molehunt: Searching for Soviet Spies in British Intelligence. New York: Berkley, 1991.

Wynne, Greville. The Man from Moscow: The Story of Wynne and Penkovsky. London: Hutchinson, 1967.

SEE ALSO

Ames (Aldrich H.) Espionage Case
Cambridge University Spy Ring
Cameras, Miniature
Hanssen (Robert) Espionage Case
Intelligence Agent
Sex-for-Secrets Scandal
United Kingdom, Intelligence and Security
Walker Family Spy Ring

Moles

views updated May 29 2018

Moles

Definition

A mole (nevus) is a pigmented (colored) spot on the outer layer of the skin (epidermis).

Description

Moles can be round, oval, flat, or raised. They can occur singly or in clusters on any part of the body. Most moles are brown, but colors can range from pinkish flesh tones to yellow, dark blue, or black.

A mole usually lasts about 50 years before beginning to fade. Some moles disappear completely, and some never lighten at all. Some moles develop stalks that raise them above the skin's surface; these moles eventually drop off.

Types of moles

Moles that are present at birth are called congenital nevi.

Other types of moles include:

  • junctional moles, which are usually brown and may be flat or slightly raised
  • compound moles, which are slightly raised, range in color from tan to dark brown, and involve pigment-producing cells (melanocytes) in both the upper and lower layers of the skin (epidermis and dermis)
  • dermal moles, which range from flesh-color to brown, are elevated, most common on the upper body, and may contain hairs
  • sebaceous moles, which are produced by over-active oil glands and are yellow and rough-textured
  • blue moles, which are slightly raised, colored by pigment deep within the skin, and most common on the head, neck, and arms of women

Most moles are benign (not cancerous), but atypical moles (dysplastic nevi) may develop into malignant melanoma, a potentially fatal form of skin cancer . Atypical moles are usually hereditary. Most are bigger than a pencil eraser, and the shape and pigmentation are irregular.

Congenital nevi are more apt to become cancerous than moles that develop after birth, especially if they are more than eight inches in diameter. Lentigo maligna (melanotic freckle of Hutchinson), most common on the face and after the age of 50, first appears as a flat spot containing two or more shades of tan. It gradually becomes larger and darker. One in three of these moles develop into a form of skin cancer known as lentigo maligna melanoma.

Demographics

Nearly everyone has at least a few moles. They generally appear by the time a person is 20 and at first resemble freckles. A mole's color and shape do not usually change; however, changes in hormone levels that occur during puberty and pregnancy can make moles larger and darker. New moles may also appear during this period. About 1 to 3 percent of all babies have one or more moles when they are born. Only about one in 1 million moles is cancerous.

Causes and symptoms

The cause of moles is unknown, although atypical moles seem to run in families and result from exposure to sunlight. During the early 2000s, researchers identified two genes known as CDKN2A and CDK4 that govern susceptibility to melanoma in humans. Other susceptibility genes are being sought. Most experts, however, think that these susceptibility genes are not sufficient by themselves to account for moles becoming cancerous but are influenced by a combination of other inherited traits and environmental factors.

When to call the doctor

Only a small percentage of moles require medical attention. A mole that has the following symptoms should be evaluated by a dermatologist (a physician specializing in skin diseases):

  • bleeds
  • itches
  • looks unusual or changes in any way

Diagnosis

A doctor who suspects skin cancer will remove all or part of the mole for microscopic examination. This procedure, which is usually performed in a doctor's office, is simple, relatively painless, and does not take more than a few minutes. It does leave a scar.

The doctor may also use a dermatoscope to examine the mole before removal. The dermatoscope, which can be used to distinguish between benign moles and melanomas, is an instrument that resembles an ophthalmoscope used to look at the eye. An oil is first applied to the mole to make the outer layers of skin transparent.

A combination of high-frequency ultrasound and color Doppler studies has also been shown to have a high degree of accuracy in distinguishing between melanomas and benign moles.

Treatment

If laboratory analysis confirms that a mole is cancerous, the dermatologist will remove the rest of the mole. Patients should realize that slicing off a section of a malignant mole will not cause the cancer to spread.

Removing a mole for cosmetic reasons involves numbing the area and using scissors or a scalpel to remove the elevated portion. The patient is left with a flat mole the same color as the original growth. Cutting out parts of the mole above and beneath the surface of the skin can leave a scar more noticeable than the mole.

Scissors or a razor can be used to temporarily remove hair from a mole. Permanent hair removal, however, requires electrolysis or surgical removal of the mole.

Prognosis

Moles are rarely cancerous and, once removed, unlikely to recur. A dermatologist should be consulted if a mole reappears after being removed.

Prevention

Wearing a sunscreen and limiting sun exposure may prevent some moles. Anyone who has moles should examine them every month and see a dermatologist if changes in size, shape, color, or texture occur or if new moles appear.

A team of researchers at Duke University reported in 2003 that topical application of a combination of 15 percent vitamin C and 1 percent vitamin E over a four-day period offered significant protection against sunburn . The researchers suggest that this combination may protect skin against aging caused by sunlight as well.

Anyone with a family history of melanoma should see a dermatologist for an annual skin examination. Everyone should know the ABCDEs of melanoma:

  • A: asymmetry, which occurs when the two halves of the mole are not identical
  • B: borders that are irregular or indistinct
  • C: color that varies in a single mole
  • D: diameter, which should be no larger than a pencil eraser (about 6 mm)
  • E: elevated above the surrounding tissue

A mole with any of these characteristics should be evaluated by a dermatologist.

Advances in photographic technique had as of 2004 made it easier to track the development of moles with the help of whole-body photographs. A growing number of hospitals are offering these photographs as part of outpatient mole-monitoring services.

Parental concerns

Very few moles are cancerous. Moles on the face or other frequently exposed areas of skin may be troubling for children. If a child is particularly troubled by a mole, a dermatologist can be consulted about its possible removal, although this often leaves a scar.

KEY TERMS

Dermatology The branch of medicine that studies and treats disorders of the skin.

Malignant melanoma The most serious of the three types of skin cancer, malignant melanoma arises from the melanocytes, the skin cells that produce the pigment melanin.

Melanin A pigment that creates hair, skin, and eye color. Melanin also protects the body by absorbing ultraviolet light.

Nevus (plural, nevi) The medical term for any anomaly of the skin that is present at birth, including moles and birthmarks.

Resources

BOOKS

Crowson, Neil A., et al. The Melanocytic Proliferations: A Comprehensive Textbook of Pigmented Lesions. New York: Wiley-Liss, 2001.

Thompson, June. Spots, Birthmarks, and Rashes: The Complete Guide to Caring for Your Child's Skin. Westport, CT: Firefly Books, 2003.

PERIODICALS

"About Moles, Melanomas, and Lasers: The Dermatologist's Schizophrenic Attitude toward Pigmented Lesions." Archives of Dermatology 139 (November 2003): 14057.

Bates, Betsy. "Imaging Devices Assist in Skin Cancer Diagnosis." Family Practice 33 (January 1, 2003): 18.

Chamilin, Sarah L. "Shedding Light on Moles, Melanoma, and the Sun." Contemporary Pediatrics 19 (June, 2002): 10210.

ORGANIZATIONS

American Academy of Dermatologists. PO Box 4014 Schaumburg, IL 601684014. Web site: <www.aad.org>.

Tish Davidson, A.M.
Maureen Haggerty
Rebecca J. Frey, PhD

Moles

views updated May 17 2018

Moles

Moles are small burrowing animals of the order Insectivora, mammals with teeth designed for crushing the outer shells of insects . The true moles and desmans (water-living moles) make up the family Talpidae, which inhabit most of North America and northern Eurasia. The similar golden moles of Africa , south of the Sahara, make up the family Chrysochloridae.

Moles vary from 1-3 in (24-75 mm) in length, plus a pink, naked tail that may be equally long, but is usually short. An adult male weighs more than 3.5 oz (100 g) and adult females less than that. A mole must eat its own weight in food each day or die, because its body has no fat preservation system.

Moles are thoroughly adapted for a life of digging. They have streamlined bodies, with nothing that might interfere with burrowing. Their front feet appear to come straight out of their bodies and are angled outward so that as they dig through soil , using first one hand, then the other, they appear to be swimming the breaststroke. Their flexible snouts are also used in digging, and their similarly tapered hind ends can easily move through soil. Unlike most mammals, whose hair lies toward the back of the body, a mole's fur can lie equally well in either direction as the animal moves in either direction. The fur is very soft.

Their functioning eyes reveal only light and dark. Instead they rely primarily on their senses of smell and touch . The surface of the muzzle is covered with thousands of tiny sensory organs that allow it to analyze even the most delicate touch. These organs, called Eimer's organs, identify food and digging sites. Their faces and forelimbs are also covered with special sensory hairs, called vibrissae.

The presence of moles is generally revealed by the presence of mounds of loosened soil called molehills. As they burrow, they toss the soil backward, and it eventually piles up on the surface. Surface burrows, which are visible from above, are dug in newly turned farm fields and very light soil, where the worms and other invertebrates the moles eat are near the top. Deep burrows, the digging of which produce molehills, are dug in heavier, drier soil where the invertebrates have moved downward to find moisture. These deep burrows may last many years and even many generations. They need to be rebuilt only if accidentally damaged. A mole marks a tunnel as its territory by giving off a strong odor from its scent gland. If the scent wears off and is not refreshed by the animal—perhaps because it has fallen prey to an owl—other animals may move into the burrow.

A mole's entire life centers around its burrow. Certain areas of a mole's burrow are used to store food, such as earthworms that have had their heads bitten off. In the center of the burrow is a nest lined with grasses and other dry material, such as scraps of paper hauled in from the surface. Every mole sleeps in its nest, but a female also raises her young in it until they have been weaned.

Moles breed in early spring, with two to eight little 2 inch (50 mm) young born in late spring. They are born blind, hairless, and red colored, weighing about 0.1 oz (3.5 g). They are out on their own by early fall. Though many die during their migration to find their own burrowing grounds, moles often live for six or seven years. They are capable of breeding when they are about a year old.

The nose of the strange star-nosed mole (Condylura cristata) of eastern North America is divided into 22 rubbery lobes, or tentacles, that make the black-furred animal look as if it has a pink flower on its nose. Each tentacle is covered with a large number of Eimer's organs. The star-nosed mole also has an unusual tail. Longer than most moles', it acts as a fat-storage organ during the breeding season. These are the only moles that lives in pairs, with the male helping to raise the young. Their fur is waterproof, which lets them dig into saturated soil, as well as swim in search of tiny crustaceans to eat.

The little American shrew-mole (Neurotrichus gibbsii) of the West Coast looks like a mole but has fur more like a shrew's, which doesn't change direction. This is the smallest American mole, averaging only 2.5-3 in (6-7 cm) in body length. Oddly enough, its closest relative lives straight across the Pacific in Japan. Shrew-moles, though they burrow like other moles, leave their shallow burrows to search for food among the litter on a forest floor.

The common, or eastern, American mole is Scalopus aquaticus. Despite its webbed back feet and its scientific name, the common American mole is not a water-living animal. It has the widest range of any American mole, from Mexico to New England to Florida. Other western moles of California include the broad-footed mole (Scapanus latimanus), the coast mole (S. orarius), and Townsend's mole (S. townsendii).

There are about 13 species of Old World moles, all in genus Talpa. The European mole (T. europaea) resides in most of Europe and over into central Russia. European moles have been known to turn their molehills into mountains , or at least "fortresses," by building quite large structures above ground. Fortresses are found only in areas that flood regularly.

Moles don't eat bulbs of flowering plants as many gardeners who have watched their flowers die believe. Instead, other creatures such as meadow mice move into mole burrows, from which they can reach those succulent plant parts. Moles are now generally left alone except on golf courses. Their very soft skins were often collected at the end of the nineteenth century for use in high-quality clothing.


Desmans

The two species of desmans make up a separate subfamily from the true moles. One (Galemys pyrenaicus) lives in the Pyrenees, the other (Desmana moschata) in Russia, both by fast-flowing rivers . Desmans are swimmers. They swim with the aid of a flattened, rudderlike tail, powerful legs, and long back feet. Their fingers and toes are also webbed.

Desmans are much larger than moles, sometimes reaching 16 in (41 cm) including their tails. Their long, flexible snouts contain nostrils that can be closed tightly against the water by special valves. Their ears can also be closed. Their fur is especially soft, and the Russian desman has long been killed for its marketable fur. Two or more desmans will share their burrows, located in the banks of a river.


Golden moles

The family of golden moles is made up of 17 species that live in Africa, south of the Sahara. They are not necessarily golden in color , though they do often have a colorful, lustrous sheen to their coats. They are tailless and, unlike true moles, blind. They are born with the remnants of useless eyes, which develop hairy coverings as they mature. The end of a golden mole's nose is leathery to aid in burrowing through the soil, though the primary digging is done by heavy, sharp claws.

Grant's desert golden mole (Eremitalpa granti) of the Namib Desert has only dry sand to dig through. Its meandering burrow collapses behind it as it continually digs. Only if rain has fallen recently does the burrow hold its shape for any length of time . Other golden moles live in moister places where their burrows hold their shape.

The large golden moles of South Africa (Chrysospalax) do not rely solely on ground invertebrates for food. They go to the surface at night to feed, hunting especially for giant worms. The surface may bring danger, however, and a golden mole that finds itself in danger may collapse dramatically, pretending to be dead. The Cape golden mole of Uganda (Chrysochloris stuhlmanni) lives at fairly high altitudes, up to 10,000 ft (3,050 m).


Resources

books

Bailey, Jill. Discovering Shrews, Moles & Voles. New York: The Bookwright Press, 1989.

Caras, Roger A. North American Mammals: Fur-Bearing Animals of the United States and Canada. New York: Meredith Press, 1967.

Gorman, Martyn L., and R. David Stone. The Natural History of Moles. Ithaca, NY: Comstock Publishing Associates, 1990.


Jean F. Blashfield

Moles (Birthmarks)

views updated Jun 08 2018

Moles (Birthmarks)

Birthmarks on the human face or body, usually classed medically as a benign form of nevus. Many superstitions exist about moles, and moleoscopy arose as a system of divination based on the position, character, and astrological connections of these markings. In folk belief, a mole on the throat was said to be a sign of good luck, but unlucky if located on the left side of the forehead near the hair. A mole on the chin, ear, or neck was said to indicate riches, but on the breast to signify poverty.

The position of moles on the various parts of the body had various meanings: On the feet and hands of a womanmany children; on the right arm and shoulder of a man or woman great lechery; on the ankles or feetmodesty in men and courage in women; on or about the kneesriches and virtue; on a woman's left kneemany children; on the thighsgreat poverty and unhappiness. An old folk rhyme from Nottingham-shire, England, indicated the belief that the position of a mole could affect rank in later life:

   "I have a mole above my right eye,
   And shall be a lady before I die."

Another belief was that hairs growing out of moles portended good luck.

During the great witchcraft manias of the sixteenth and seventeenth centuries, such birthmarks as moles, as well as warts, were considered "devil's marks" if they did not bleed when pricked. Professional witch finders like the infamous Matthew Hopkins (died 1647) used pricking on suspected witches. Moles, warts, scars, or other birthmarks were pricked with a long pin; if there was no pain or bleeding, the suspect was claimed to be a witch. Special pricking tools like thin daggers were developed, and some enthusiastic witch prickers (who claimed a substantial fee for each convicted witch) even used trick pricking tools with a hollow shaft and retractable blade, to make sure that the suspect would feel no pain and there would be no bleeding.

Moles (Animal)

views updated Jun 08 2018

Moles (Animal)

Many superstitions grew up around moles. It was a common error to believe that moles were blind, whereas in fact their eyes are small and often hidden in the hair. As late as Shakepeare's time, moles were popularly believed to be blind, as indicated in the dramatist's play The Tempest: "Pray you tread softly, that the blind mole may not hear a footfall."

Other popular beliefs were that if moles came into a meadow it was a sign of fair weather, that if a mole dug his hole very deep, you could expect a very severe winter, and that if a mole threw up earth during a frost, the frost would disappear in two days.

Some Gypsies believed that moles never touched earth that had been stained with blood. In Britain, farm laborers used to wear the forelegs and a hind leg of a mole in a bag around the neck to protect against toothache. It was also believed that if you pulled molehills up on St. Sylvester's Day (December 31), the moles would not throw up earth again.

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Moles

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