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Nevi
Nevus (plural nevi) is a nonspecific medical term for a visible, circumscribed, chronic lesion of the skin or mucosa. The term originates from ''nævus'', which is Latin for "birthmark"; however, a nevus can be either congenital (present at birth) or acquired. Common terms, including mole, birthmark, and beauty mark, are used to describe nevi, but these terms do not distinguish specific types of nevi from one another. Classification The term ''nevus'' is applied to a number of conditions caused by neoplasias and hyperplasias of melanocytes, as well as a number of pigmentation disorders, both hypermelanotic (containing increased melanin, the pigment responsible for skin color) and hypomelanotic (containing decreased melanin). Suspicious skin moles which are multi-colored or pink may be a finding in skin cancer. Increased melanin Usually acquired * Melanocytic nevus ** Melanocytic nevi can be categorized based on the location of melanocytic cells *** Junctional: epidermis * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanocytic Nevus
A melanocytic nevus (also known as nevocytic nevus, nevus-cell nevus and commonly as a mole) is a type of melanocytic tumor that contains nevus cells. Some sources equate the term mole with "melanocytic nevus", but there are also sources that equate the term mole with any nevus form. The majority of moles appear during the first two decades of a person's life, with about one in every 100 babies being born with moles. Acquired moles are a form of benign neoplasm, while congenital moles, or congenital nevi, are considered a minor malformation or hamartoma and may be at a higher risk for melanoma. A mole can be either subdermal (under the skin) or a pigmented growth on the skin, formed mostly of a type of 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 and can occur in all mammalian species, but have been documented most extensively in human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanocytic Nevus
A melanocytic nevus (also known as nevocytic nevus, nevus-cell nevus and commonly as a mole) is a type of melanocytic tumor that contains nevus cells. Some sources equate the term mole with "melanocytic nevus", but there are also sources that equate the term mole with any nevus form. The majority of moles appear during the first two decades of a person's life, with about one in every 100 babies being born with moles. Acquired moles are a form of benign neoplasm, while congenital moles, or congenital nevi, are considered a minor malformation or hamartoma and may be at a higher risk for melanoma. A mole can be either subdermal (under the skin) or a pigmented growth on the skin, formed mostly of a type of 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 and can occur in all mammalian species, but have been documented most extensively in human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital Melanocytic Nevus
The congenital melanocytic nevus is a type of melanocytic nevus (or mole) found in infants at birth. This type of birthmark occurs in an estimated 1% of infants worldwide; it is located in the area of the head and neck 15% of the time. Signs and symptoms The congenital melanocytic nevus appears as a circumscribed, light brown to black patch or plaque, potentially very heterogeneous in consistency, covering any size surface area and any part of the body. As compared with a melanocytic nevus, congenital melanocytic nevi are usually larger in diameter and may have excess terminal hair, a condition called hypertrichosis. If over projected adult diameter with hypertrichosis, it is sometimes called giant hairy nevus; more usually these largest forms are known as large or giant congenital melanocytic nevus. The estimated prevalence for the largest forms is 0.002% of births. Melanocytic nevi often grow proportionally to the body size as the child matures. As they mature, they often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysplastic Nevus
A dysplastic nevus or atypical mole is a nevus (mole) whose appearance is different from that of common moles. In 1992, the NIH recommended that the term "dysplastic nevus" be avoided in favor of the term "atypical mole". An atypical mole may also be referred to as an atypical melanocytic nevus, atypical nevus, B-K mole, Clark's nevus, dysplastic melanocytic nevus, or nevus with architectural disorder. Dysplastic nevi often grow to larger than ordinary moles and may have irregular and indistinct borders. Their color may not be uniform and may range from light pink to very dark brown. They usually begin flat, but parts may be raised above the skin surface. See ABCDE and "ugly duckling" characteristics below. Dysplastic nevi can be found anywhere, but are most common on the trunk in men, and on the calves in women. There is some controversy in the dermatology community as to whether or not the "dysplastic"/"atypical" nevus exists. Some have argued that the terms "dysplastic" and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanoma
Melanoma, also redundantly known as malignant melanoma, is a type of skin cancer that develops from the pigment-producing cells known as melanocytes. Melanomas typically occur in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In women, they most commonly occur on the legs, while in men, they most commonly occur on the back. About 25% of melanomas develop from moles. Changes in a mole that can indicate melanoma include an increase in size, irregular edges, change in color, itchiness, or skin breakdown. The primary cause of melanoma is ultraviolet light (UV) exposure in those with low levels of the skin pigment melanin. The UV light may be from the sun or other sources, such as tanning devices. Those with many moles, a history of affected family members, and poor immune function are at greater risk. A number of rare genetic conditions, such as xeroderma pigmentosum, also increase the risk. Diagnosis is by biopsy and analysis of any skin lesio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spitz Nevus
A Spitz nevus is a benign skin lesion. A type of melanocytic nevus, it affects the epidermis and dermis.LeBoit, PE, Burg G, Weedon D, Sarasin A. (Eds) World Health Organization Classification of Tumours: Pathology and Genetics of Skin Tumours. Lyon: ''IARC''Press. 2006. It is also known as an epithelioid and spindle-cell nevus, and misleadingly as a benign juvenile melanoma, and Spitz's juvenile melanoma). The name ''juvenile melanoma'' is generally no longer used as it is neither a melanoma, nor does it occur only in children.Crotty, K. Spitz Naevus: Histological features and distinction from malignant melanoma. Australasian Journal of Dermatology. 38 (suppl): S49-S53. 1997. Pathophysiology The cause of Spitz nevi is not yet known. There is an association with sunburn, but causation is not established. Genetic studies of Spitz nevi have shown that most cells have the normal number of chromosomes, however a minority (25%) of cells have been shown to contain extra copies of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevus Sebaceous
Nevus sebaceus or sebaceous nevus (the first term is its Latin name, the second term is its name in English; also known as an "organoid nevus"James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . and "nevus sebaceus of Jadassohn"Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. .) is a congenital, hairless plaque that typically occurs on the face or scalp. Such nevi are classified as epidermal nevi and can be present at birth, or early childhood, and affect males and females of all races equally.Teng, Joyce M.CNevus sebaceous, University of Wisconsin Hospitals and Clinics Authority, last updated 16 November 2007. The condition is named for an overgrowth of sebaceous glands, a relatively uncommon hamartoma A hamartoma is a mostly benign, local malformation of cells that resembles a neoplasm of local tissue but is usually due to an overgrowth of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Becker's Nevus
Becker's nevus (also known as "Becker's melanosis", "Becker's pigmentary hamartoma", "nevoid melanosis", and "pigmented hairy epidermal nevus") is a benign skin disorder predominantly affecting males. The nevus can be present at birth, but more often shows up around puberty. It generally first appears as an irregular pigmentation (melanosis or hyperpigmentation) on the torso or upper arm (though other areas of the body can be affected), and gradually enlarges irregularly, becoming thickened and often hairy (hypertrichosis). The nevus is due to an overgrowth of the epidermis, pigment cells ( melanocytes), and hair follicles. This form of nevus was first documented in 1948 by American dermatologist Samuel William Becker (1894–1964). Clinical information Medical knowledge and documentation of this disorder is poor, likely due to a combination of factors including recent discovery, low prevalence, and the more or less aesthetic nature of the effects of the skin disorder. Thus t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevus Spilus
Nevus spilus, also known as speckled lentiginous nevus, is a light brown or tan birth mark, speckled with small, dark spots or small bumps. If it occurs in a segmental pattern then it is sometimes referred to as a Zosteriform speckled lentiginous nevus. It may be associated with types of phakomatosis pigmentovascularis. Prevalence is between 0.2% and 2.8%. See also * Phakomatosis pigmentokeratotica * Skin lesion A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of th ... * List of cutaneous conditions References External links Melanocytic nevi and neoplasms {{Cutaneous-condition-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Nevus
A blue nevus is a type of coloured mole, typically a single well-defined blue-black bump. The blue colour is caused by the pigment being deep in the skin. Diagnosis is by visualisation and dermoscopy. A biopsy is sometimes performed, or the whole lesion surgically removed. The outcome is generally good but there is a small chance of cancerous transformation. Differential diagnosis includes dermatofibroma and melanoma. Blue nevi are more common in females than males. It was first studied in 1906 by Tièche, a student of Josef Jadassohn. Classification Blue nevi may be divided into the following types: * A ''patch blue nevus'' (also known as an "acquired dermal melanocytosis", and "dermal melanocyte hamartoma") is a cutaneous condition characterized by a diffusely gray-blue area that may have superimposed darker macules. * A ''blue nevus of Jadassohn–Tièche'' (also known as a "common blue nevus", and "nevus ceruleus") is a cutaneous condition characterized by a steel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigmented Spindle Cell Nevus
A pigmented spindle cell nevus is a skin condition characterized by a dark brown to black macule or papule, usually less than 6 mm. It was characterized in 1975. See also * Partial unilateral lentiginosis * List of cutaneous conditions * Spitz nevus A Spitz nevus is a benign skin lesion. A type of melanocytic nevus, it affects the epidermis and dermis.LeBoit, PE, Burg G, Weedon D, Sarasin A. (Eds) World Health Organization Classification of Tumours: Pathology and Genetics of Skin Tumours. L ... References External links Melanocytic nevi and neoplasms {{Dermatology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Cancer
Skin cancers are cancers that arise from the skin. They are due to the development of abnormal cells that have the ability to invade or spread to other parts of the body. There are three main types of skin cancers: basal-cell skin cancer (BCC), squamous-cell skin cancer (SCC) and melanoma. The first two, along with a number of less common skin cancers, are known as nonmelanoma skin cancer (NMSC). Basal-cell cancer grows slowly and can damage the tissue around it but is unlikely to spread to distant areas or result in death. It often appears as a painless raised area of skin that may be shiny with small blood vessels running over it or may present as a raised area with an ulcer. Squamous-cell skin cancer is more likely to spread. It usually presents as a hard lump with a scaly top but may also form an ulcer. Melanomas are the most aggressive. Signs include a mole that has changed in size, shape, color, has irregular edges, has more than one color, is itchy or bleeds. More th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
