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Related to amelanotic melanoma: Nodular melanoma
an anaplastic melanoma consisting of cells derived from melanocytes but not forming melanin.
a melanoma that lacks melanin. See also melanoma.
amelanotic melanomaA rare, poorly differentiated form of melanoma, which arises in patients with a previous pigmented melanoma, in particular the desmoplastic melanomas.
amelanotic melanomaDermatology A rare, poorly differentiated form of melanoma, which occurs in Pts with a previous pigmented melanoma. See Melanoma, Regression.
amelanotic melanomaneoplastic skin lesion not characterized by an increase in local skin pigmentation, and thus difficult to diagnose; characteristic of one-third of skin melanomas
a tumor arising from melanocytes, dendritic cells of neuroectodermal origin, or melanoblasts. They are most common in the skin, eye and oral cavity of dogs and aged gray horses, but occur occasionally as congenital lesions in pigs, goats and cattle. An inherited, malignant melanoma is recorded in swordtail-platyfish hybrids.
one containing little or no melanin.
usually pigmented plaques or nodules. Those with junctional activity are analogous to the human compound junctional nevus.
congenital melanoma of pigs
a single or multiple pigmented tumor of the skin or viscera that grows slowly and may metastasize. Spontaneous regression is common. An inherited form seen in Sinclair miniature pigs.
a tumor which arises from rests of melanocytes in the dermis, remnants of neural crest precursors. Pigmentation is variable. It is usually benign.
a malignant, rapidly growing, frequently ulcerated mass, consisting of either spindle cells or epithelioid cells or a mixture of the two, with a marked tendency to metastasize. The tumor cells may or may not (amelanotic) be pigmented. Although melanomas in pigs and cattle are usually benign and are not treated, those in horses, dogs, cats and occasional cases in sheep, goats and pigs are malignant. Called also nevocarcinoma.