|
Nevus
Nevus () is a nonspecific medical terminology, medical term for a visible, circumscribed, chronic (medicine), chronic lesion of the skin or mucosa. The term originates from , which is Latin for "birthmark"; however, a nevus can be either congenital (present at birth) or acquired. Common terms (''mole'', ''birthmark'', ''beauty mark'', etc.) 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 Neoplasm, 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 ... [...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 usually a Malignancy, noncancerous condition of pigment-producing Human skin, skin cells. It is a type of melanocytic tumor that contains nevus cells. 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 (singular "nevus"), occurring commonly in humans. 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 2 decades of a person's life, with about 1 in every 100 babies being born with moles. Acquired moles are a form of Benign tumor, benign neoplasm, while congenital moles, or congenital nevi, are considered a min ... [...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" a ... [...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 of ... [...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] |
Nevus Depigmentosus
Nevus depigmentosus is a loss of pigment in the skin which can be easily differentiated from vitiligo. Although age factor has not much involvement in the nevus depigmentosus but in about 19% of the cases these are noted at birth. Their size may however grow in proportion to growth of the body. The distribution is also fairly stable and are nonprogressive hypopigmented patches. The exact cause of nevus depigmentosus is still not clearly understood. A sporadic defect in the embryonic development has been suggested to be a causative factor. It has been described as "localised albinism", though this is incorrect. Those with nevus depigmentosus may be prone to sunburn due to the lack of pigment, and the patient should use good sun protection. Sunscreen should be applied to all exposed skin, since reduced tanning of normal skin will decrease the contrast with hypopigmented skin. Most patients with nevus depigmentosus do not pursue treatment for their lesion. There is no way to repigmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spitz Nevus
A Spitz nevus is a benign Skin condition#Lesions, skin lesion. A type of melanocytic nevus, it affects the Epidermis (skin), 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 hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevus Anemicus
Nevus anemicus is a congenital disorder characterized by macules of varying size and shape that are paler than the surrounding skin and cannot be made red by trauma, cold, or heat.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. Page 582. . The paler area is due to the blood vessels within the area which are more sensitive to the body’s normal vasoconstricting chemicals. Signs and symptoms This benign patch appears on the skin at birth or in early childhood. In most people these are under in size. If there is doubt about the diagnosis, rubbing the area causes the skin around the lesion to become red while the lesion itself does not change in color. Often the patches are difficult to see against the background color of the patient’s skin, but if sunburn develops, then the white area stands out prominently. The involved area is lighter than the normal skin, not because of a loss of pigment occurs, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanoma
Melanoma is the most dangerous type of skin cancer; it develops from the melanin-producing cells known as melanocytes. It typically occurs in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In very rare cases melanoma can also happen in the lung which is known as primary pulmonary melanoma and only happens in 0.01% of primary lung tumors. In women, melanomas most commonly occur on the legs; while in men, on the back. Melanoma is frequently referred to as malignant melanoma. However, the medical community stresses that there is no such thing as a 'benign melanoma' and recommends that the term 'malignant melanoma' should be avoided as redundant. About 25% of melanomas develop from nevus, moles. Changes in a mole that can indicate melanoma include increaseespecially rapid increasein size, irregular edges, change in color, itchiness, or nevus#Classification, skin breakdown. The primary cause of melanoma is ultraviolet light (UV) exposure in th ... [...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 condition#Lesions, skin lesion. A type of melanocytic nevus, it affects the Epidermis (skin), epidermis and dermis.LeBoit, PE, Burg G, Weedon D, Sarasin A. (Eds) World Health Organization Classification of Tumours: ... References External links Melanocytic nevi and neoplasms {{Cutaneous-condition-stub} ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birthmark
A birthmark is a congenital, benign irregularity on the skin which is present at birth or appears shortly after birth—usually in the first month. Birthmarks can occur anywhere on the skin. They are caused by overgrowth of blood vessels, melanocytes, smooth muscle, fat, fibroblasts, or keratinocytes. Dermatologists divide birthmarks into two types: pigmented birthmarks and vascular birthmarks. Pigmented birthmarks caused by excess skin pigment cells include: moles, café au lait spots, and Mongolian spots. Vascular birthmarks, also called red birthmarks, are caused by increased blood vessels and include macular stains (salmon patches), hemangiomas, and port-wine stains. A little over 1 in 10 babies have a vascular birthmark present by age 1. Several birthmark types are part of the group of skin lesions known as nevi or naevi, which is Latin for "birthmarks". Birthmarks occur as a result of a localized imbalance in factors controlling the development and migration of skin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nevus Of Ota
Nevus of Ota is a hyperpigmentation that occurs on the face, most often appearing on the white of the eye. It also occurs on the forehead, nose, cheek, periorbital region, and temple. It was first reported by Masao Ōta of Japan in 1939. Cause Nevus of Ota is caused by the entrapment of melanocytes in the upper third of the dermis. It is found only on the face, most commonly unilaterally, rarely bilaterally and involves the first two branches of the trigeminal nerve. The sclera is involved in two-thirds of cases (causing an increased risk of glaucoma). It should not be confused with Mongolian spot, which is a birthmark caused by entrapment of melanocytes in the dermis but is located in the lumbosacral region. Women are nearly five times more likely to be affected than men, and it is rare among Caucasian people. Nevus of Ota may not be congenital, and may appear during puberty. Skin treatment A Q-switched 1064 nm laser has been successfully used to treat the condition. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
