Precancerous conditions of the skin have the potential to develop into melanoma.
An atypical mole (also called dysplastic nevus) is an unusual mole that looks different from an ordinary mole. Atypical moles are more likely than ordinary moles to develop into melanoma. Atypical moles are most commonly found on the back, chest, buttocks, breasts and scalp. They can be found on sun-exposed and non-exposed skin sites.
The following risk factor may increase a person’s chance of developing atypical moles:
The signs and symptoms of an atypical mole may include:
If the signs and symptoms of an atypical mole are present, or if the doctor suspects an atypical mole, tests will be done to make a diagnosis. Tests may include:
Treatment options for atypical moles may include:
Congenital melanocytic nevi are birthmarks or large moles that are present at birth or may develop during early childhood. There may be one or more present. People who are born with a congenital nevus or who develop one during early childhood have an increased risk of developing melanoma.
There are no known risk factors for developing congenital melanocytic nevi. However, researchers have suggested that a cell mutation may be a cause.
The signs and symptoms of congenital melanocytic nevi may include:
If the signs and symptoms of a congenital melanocytic nevi are present, or if the doctor suspects a congenital melanocytic nevi, tests will be done to make a diagnosis. Tests may include:
Treatment options for congenital melanocytic nevi depend on the size and location of the nevus, its potential to become cancerous and the person’s age.
For a small (less than 1.5 cm) or medium (between 1.5 and 20 cm) congenital nevus, treatment may include:
For large (greater than 20 cm) congenital nevus, treatment may include:
For lesions that are too large to be removed by surgery, treatment may include:
Lentigo maligna is a precancerous condition that may lead to lentigo maligna melanoma. Lentigo maligna is a spreading brown patch, often with considerable variation in colour. It is usually flat. It can slowly get bigger over years. Lentigo maligna is most commonly found on chronically sun-exposed areas, such as the face, neck, back of hands and lower legs.
Lentigo maligna can be confused with a benign condition called lentigo simplex. Lentigo simplex lesions are brown patches that develop on the face of elderly people from skin damage.
The following risk factor may increase a person’s chance of developing lentigo maligna:
The signs and symptoms of lentigo maligna may include:
If the signs and symptoms of lentigo maligna are present, or if the doctor suspects lentigo maligna, tests will be done to make a diagnosis. Tests may include:
Treatment options for lentigo maligna may include: