Basal cell carcinoma: Most common and least dangerous type of skin cancer; grows slowly and rarely spreads; usually on face in form of small round lump either red, pale, or pearly color; a type of skin cancer in which the cancer cells resemble the basal cells of the epidermis.
Benign tumor: Not a cancer; grows slowly; does not spread to other parts of the body like a cancer can.
Biopsy: The removal of a sample of tissue that is then examined under a microscope.
Cancer: Uncontrolled growth and spread of abnormal cells.
Carcinoma: A type of cancer that begins in the lining or covering tissues of an organ.
Dermis: Underlying layers of the skin, containing hair follicles, fat cells, and sweat glands.
Epidermis: Outermost layer of the skin, containing basal cells and squamous cells.
Immune: Protected or safe from disease.
Malignant: Cancerous; grows uncontrollably.
Malignant tumor: Cancer that grows uncontrollably and can spread to other parts of the body; if left untreated it leads to death.
Melanin: The brown pigment which gives skin its color; the amount of this substance accounts for variations in skin color in different people and different races.
Melanocytes: Special cells in the epidermis of the skin which makes melanin.
Melanoma: Potentially fatal form of skin cancer; it can spread rapidly; usually curable if found early; cancer that begins in the melanocytes.
Ozone layer: Ozone gas occurs naturally in the upper atmosphere where it forms a layer that protects the Earth's surface by absorbing a large amount of harmful UV radiation.
Pre-cancerous: A term used to describe a condition that may or is likely to become cancer.
Skin cancer: There are three main types: basal, squamous, and melanoma. Skin cancer rates in Florida are one of the highest in the country.
Squamous cell carcinoma: Common form of skin cancer that appears on areas of the body most exposed to the sun; starts as scaling red areas which grow rapidly, bleed easily, and may form sores that do not heal; a type of skin cancer in which the cells resemble the squamous cells of the epidermis.
Sun protection factor (SPF): SPF indicates the degree of protection the sunscreen provides. A sunscreen with an SPF of 4 provides the least protection; sunscreen with an SPF of at least 15 provides the most protection. SPF is based on how long unprotected skin takes to burn when exposed to artificial sunlight.
Sunscreen: A substance that blocks the effects of the sun's harmful rays; using sunscreen can reduce the risk of skin cancer.
Tumor: An abnormal growth of tissue on or in the body formed by a collection of cells. A tumor may be benign (not a cancer) or malignant (a cancer).
Ultraviolet radiation (UV radiation): The sun's harmful rays. UV radiation is made up of three parts: UVA, UVB, and UVC; invisible rays that are part of the energy that comes from the sun.
UVA: originally believed to be harmless but now believed to cause skin damage.
UVB: causes skin damage, sunburn, and skin cancer.
UVC: none reaches the Earth's surface; it is all absorbed by the ozone layer.
This page last reviewed April 24, 2007
United States Department of Health Human Services