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 * Intradermal: dermis * Compound: epidermis and dermis * Atypical (dysplastic) nevus: This type of nevus must be diagnosed based on histological features. Clinically, atypical nevi are characterized by variable pigmentation and irregular borders. * Becker's nevus * Blue nevus (rarely congenital): A classic blue nevus is usually smaller than 1 cm, flat, and blue-black in color. * Hori's nevus * Nevus spilus (speckled lentiginous nevus): This lesion includes dark speckles within a tan-brown background. * Pigmented spindle cell nevus * Spitz nevus * Zosteriform lentiginous nevus Usually congenital * Congenital melanocytic nevus * These nevi are often categorized based on size, however, the lesions usually grow in proportion to the body over time, so the category may change over an individual's life. This categorization is important because large congenital melanocytic nevi are associated with an increased risk of melanoma, a serious type of skin cancer. * Small: File:Conjunctival nevus.Conjunctival nevus of a 32-year-old male File:Micrograph of an intradermal melanocytic nevus.Micrograph of an intradermal melanocytic nevus File:Normal mole (1).Acquired melanocytic nevi File:Dysplastic nevi (4).Atypical nevus File:Becker's nevus of shoulder.Becker's nevus File:Blue Nevus.Blue nevus File:Naevus-spilus.Nevus spilus File:Spitz nevus.Spitz nevus File:Congenital nevus from CDC.Congenital melanocytic nevus File:Nevus of Ota Before IBRITE C.Nevus of Ota File:Compound nevus left buttock.Compound nevus, left buttock Decreased melanin Acquired * Nevus anemicus Congenital * Nevus depigmentosus File:Nevus anemicus.Nevus anemicus File:Nevus Depigmentosus.Nevus depigmentosus Additional types of nevi do not involve disorders of pigmentation or melanocytes. These additional nevi represent hamartomatous proliferations of the epithelium, connective tissue, and vascular malformations. Epidermal nevi These nevi represent excess growth of specific cells types found in the skin, including those that make up oil and sweat glands. * Verrucous epidermal nevus * Nevus sebaceous * Nevus comedonicus * Eccrine nevus * Apocrine nevus Connective tissue nevi Connective tissue nevi represent abnormalities of collagen in the dermis, the deep layer of the skin. * Collagenoma * Elastoma Vascular nevi These nevi represent excess growth of blood vessels, including capillaries. * Nevus simplex (nevus flammeus nuchae), also known as a stork bite or salmon patch. File:NaevusSebaceus res.Nevus sebaceous File:Nevus flammeus nuchae ("stork bite" "Storchenbiss").Nevus flammeus nuchae Intramucosal nevi An intramucosal nevus is a nevus within the mucosa as found in for example the mouth and genital areas. In the mouth, they are found most frequently on the hard palate. They are typically light brown and dome-shaped. Intramucosal nevi account for 64% of all reported case of oral nevi.
symptom of Melanoma
symptom of Skin cancer
symptom of Basal-cell carcinoma
symptom of Mucosal melanoma
symptoms of Mucosal melanoma
symptom of Hodgkin lymphoma
symptom of Lymphoma
symptom of Psoriasis