Skin cancer is the most common type of cancer, probably making up more than half of all diagnosed cases of cancer, according to the American Cancer Society (ACS). The incidence of skin cancer is rising dramatically in the United States. More than one million cases of nonmelanoma and 59,600 cases of melanoma skin cancer were diagnosed in 2005, and more than 7,910 deaths from melanoma and 2,800 deaths from nonmelanoma skin cancers are expected in 2006. In fact, between 40 percent and 50 percent of people in the U.S. over age 65 will develop nonmelanoma skin cancer. This type of cancer is highly treatable when diagnosed in its early stages, and is usually relatively easy to diagnose.
The majority of lifetime sun exposure occurs before age 20 and skin cancer can take 20 years or more to develop. In fact, very young children who experience as few as two to three severe sunburns are believed to have an increased risk of developing skin cancer later in life. That's not to say you should ignore your risk of developing skin cancer. You need to be concerned about skin cancer, whether your sun bathing days are over or you still spend time pursuing the perfect tan.
The Structure of Skin
The skin is the largest organ in your body, and is the body's first defense against disease and infection. It also protects your internal organs from injuries. The skin regulates body temperature, prevents excess fluid loss and also helps to remove excess water and salt from your body.
Skin is composed of two layers: the epidermis (the outermost layer of skin) and the dermis (the lower layer). The epidermis itself has four layers: the stratum corneum, the granular layer, the squamous cell layer and the basal cell layer. Keratin (dead, dense protein cells) makes up the stratum corneum or outer layer of the epidermis—the skin layer that can be seen and felt.
The granular layer moves the dead keratin cells to the surface of the epidermis. The squamous cell layer produces keratin for the stratum corneum and also transports water. The basal cell layer is the lowest layer of the epidermis. This is where squamous cells are produced and also where the cells that produce melanin, or skin pigment, reside.
The dermis is the deeper layer of skin. It is a diverse combination of blood vessels, hair follicles and sebaceous glands or oil glands. The proteins collagen and elastin are found in the dermis. They provide support and elasticity to the skin. The sun's rays eventually break down these proteins. With age, the skin naturally begins to wrinkle and sag.
The subcutaneous level, or subcutis, is a layer of fatty tissue that provides nourishment to the dermis and upper layers of skin. It also conserves body heat and cushions internal organs against trauma. Blood vessels, nerves, sweat glands and deeper hair follicles are found here.
Types of Skin Cancer
There are two main groups of skin cancer: nonmelanoma skin cancer, the most common type of skin cancer, and melanoma (sometimes referred to as "malignant melanoma" skin cancer).
According to the ACS, basal cell carcinoma makes up 75 percent of skin cancers, and squamous cell carcinomas account for about 20 percent; together, these two types account for 95percent of all new cases of skin cancer. Over one million cases of nonmelanoma skin cancer are diagnosed every year in the U.S. Men have a higher risk than women of developing these skin cancers.
Melanoma is the least common, but most aggressive of the three types of skin cancer. It originates in the skin's melanocytes—the cells that produce pigment, or melanin.
In 2006, the ACS estimates that 62,190 new cases of melanoma will be diagnosed in the United States—about four percent of all diagnosed skin cancers. But melanoma accounts for about 75 percent of skin cancer deaths, according to the American Academy of Dermatology (AAD). One person dies of melanoma almost every hour (every 68 minutes).
Risk Factors
Anyone can develop skin cancer, but people with fair complexions are more susceptible to precancerous conditions and skin cancer than people with darker skin tones. Caucasians have a 10 times increased risk of developing skin cancer than African Americans. That's because darker skin has more melanin, which provides some natural protection against the sun's damaging rays. In addition to fair skin, other risk factors for skin cancer include:
a personal history of skin cancer
a tendency to freckle or burn easily
lots of sun exposure throughout your life
many sunburns as a child or adolescent
family history of the skin cancer or conditions that are more likely to develop into skin cancer
chronic, non-healing scarring
radiation therapy
exposure to toxic materials, such as arsenic, coal tar, creosote
exposure to certain subtypes of human papilloma virus (HPV 6,11,16,18) especially in people with compromised immune systems
taking immunosuppressant drugs (after an organ transplant, for instance)
The majority of lifetime sun exposure occurs before age 20 and skin cancer can take 20 years or more to develop. In fact, very young children who experience as few as two to three severe sunburns are believed to have an increased risk of developing skin cancer later in life. That's not to say you should ignore your risk of developing skin cancer. You need to be concerned about skin cancer, whether your sun bathing days are over or you still spend time pursuing the perfect tan.
The Structure of Skin
The skin is the largest organ in your body, and is the body's first defense against disease and infection. It also protects your internal organs from injuries. The skin regulates body temperature, prevents excess fluid loss and also helps to remove excess water and salt from your body.
Skin is composed of two layers: the epidermis (the outermost layer of skin) and the dermis (the lower layer). The epidermis itself has four layers: the stratum corneum, the granular layer, the squamous cell layer and the basal cell layer. Keratin (dead, dense protein cells) makes up the stratum corneum or outer layer of the epidermis—the skin layer that can be seen and felt.
The granular layer moves the dead keratin cells to the surface of the epidermis. The squamous cell layer produces keratin for the stratum corneum and also transports water. The basal cell layer is the lowest layer of the epidermis. This is where squamous cells are produced and also where the cells that produce melanin, or skin pigment, reside.
The dermis is the deeper layer of skin. It is a diverse combination of blood vessels, hair follicles and sebaceous glands or oil glands. The proteins collagen and elastin are found in the dermis. They provide support and elasticity to the skin. The sun's rays eventually break down these proteins. With age, the skin naturally begins to wrinkle and sag.
The subcutaneous level, or subcutis, is a layer of fatty tissue that provides nourishment to the dermis and upper layers of skin. It also conserves body heat and cushions internal organs against trauma. Blood vessels, nerves, sweat glands and deeper hair follicles are found here.
Types of Skin Cancer
There are two main groups of skin cancer: nonmelanoma skin cancer, the most common type of skin cancer, and melanoma (sometimes referred to as "malignant melanoma" skin cancer).
According to the ACS, basal cell carcinoma makes up 75 percent of skin cancers, and squamous cell carcinomas account for about 20 percent; together, these two types account for 95percent of all new cases of skin cancer. Over one million cases of nonmelanoma skin cancer are diagnosed every year in the U.S. Men have a higher risk than women of developing these skin cancers.
Melanoma is the least common, but most aggressive of the three types of skin cancer. It originates in the skin's melanocytes—the cells that produce pigment, or melanin.
In 2006, the ACS estimates that 62,190 new cases of melanoma will be diagnosed in the United States—about four percent of all diagnosed skin cancers. But melanoma accounts for about 75 percent of skin cancer deaths, according to the American Academy of Dermatology (AAD). One person dies of melanoma almost every hour (every 68 minutes).
Risk Factors
Anyone can develop skin cancer, but people with fair complexions are more susceptible to precancerous conditions and skin cancer than people with darker skin tones. Caucasians have a 10 times increased risk of developing skin cancer than African Americans. That's because darker skin has more melanin, which provides some natural protection against the sun's damaging rays. In addition to fair skin, other risk factors for skin cancer include:
a personal history of skin cancer
a tendency to freckle or burn easily
lots of sun exposure throughout your life
many sunburns as a child or adolescent
family history of the skin cancer or conditions that are more likely to develop into skin cancer
chronic, non-healing scarring
radiation therapy
exposure to toxic materials, such as arsenic, coal tar, creosote
exposure to certain subtypes of human papilloma virus (HPV 6,11,16,18) especially in people with compromised immune systems
taking immunosuppressant drugs (after an organ transplant, for instance)
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