Skin Cancer
About Different Types of Skin Cancer: Melanoma, Basal Cell Carcinoma, Squamous Cell Carcinoma and Keratoacanthoma
Skin cancer is the most commonly diagnosed cancer in the United States. The disease is grouped into two categories based on the type of cell from which the cancer originates - melanoma and non-melanoma; the latter includes basal cell carcinoma and squamous cell carcinoma.1 It is estimated that one in five Americans will develop some form of skin cancer during his or her lifetime. 2 Most cases of skin cancer can be cured if caught and treated when the disease is restricted to a small area of the skin. However, if the cancer spreads into the surrounding tissue or to other parts of the body, the disease can have devastating consequences and may become deadly.3
Layers of the Skin 1
The skin is composed of three layers,the epidermis, dermis and hypodermis (or subcutis). The epidermis, the top layer of the skin, is made up of many different cell types that give the skin structure and color. Basal cells are involved in regenerating skin and melanocytes produce the skin's pigment giving it color.
Melanoma
Melanoma is the less common, but more serious category of skin cancer that originates in the skin's pigment-producing cells known as melanocytes.3 According to the American Cancer Society, fewer than five percent of skin cancer diagnoses are melanoma, but melanoma accounts for a large majority of skin cancer deaths.3 Cases of melanoma have been increasing for at least 30 years.3 In 2012, it is estimated that more than 76,000 people will be diagnosed with melanoma and nearly 9,200 people will die from the disease.3
Eighty-four percent of melanoma cases are diagnosed and treated when the disease is restricted to a small area of the skin. However, if the cancer spreads to other tissues and organs (Stage IV, advanced or metastatic melanoma), a person's prognosis becomes worse. Only 15 percent of people with advanced melanoma are expected to live for five years or longer.3
Treatment
- Common treatments include surgery, chemotherapy, immunotherapy and radiation. However, treatment varies based on the stage of the disease. Early-stage (Stage I) melanoma is often treated with surgery, while advanced disease has few treatment options available and is not curable.3,4
- Current treatments for advanced melanoma include targeted therapy, chemotherapy, surgery, radiation and immunotherapy.3
Basal Cell Carcinoma (BCC)
The most common type of skin cancer is basal cell carcinoma (BCC), a slow-growing disease that originates in the skin's basal cells, which replace old cells that wipe away from the surface of the skin.1,2 Approximately 80 percent of non-melanoma skin cancers diagnosed are BCC.1
BCC is generally curable by surgery when caught early or restricted to a small area of the skin.3
In rare cases, if BCC is left untreated or comes back in the same location after surgery or radiation, it can advance further into surrounding areas and cause disfiguring and debilitating effects. People with locally advanced BCC have lesions that frequently occur on the face that are inoperable or disfiguring and can't be removed by surgery without causing irreparable damage. In some cases, advanced forms of BCC may lead to severe deformity or impaired function of the affected organs.1,5
The disease can also, in rare cases, spread to other parts of the body (metastasize).1 The length of time that people may live after BCC has spread to other parts of the body varies. In metastatic disease, median survival is approximately eight months.6
Treatment
- Common treatments include surgery, radiation, immunotherapy, chemotherapy, topical therapy or light therapy.1,7
- Current treatments for advanced forms of BCC include targeted therapy, surgery, radiation and chemotherapy.8
Squamous Cell Carcinoma and Keratoacanthoma
Squamous cell carcinoma (SCC) originates from squamous cells, which are found in the tissue that forms the surface of the skin.1 Like BCC, most cases of SCC may be cured if identified and treated when it is restricted to a small area of the skin.3
Keratocanthoma, a type of SCC, is a rapidly growing skin cancer that is often found on the head or neck. In some people, this cancer may disappear on its own and will rarely spread to nearby organs or tissues.1
Treatment
- Current treatments include surgery, radiation, chemotherapy or topical therapy.1
Rare types of non-melanoma skin cancer that account for less than one percent of all types of skin cancer, include Merkel cell carcinoma, Kaposi sarcoma, cutaneous lymphoma, skin adnexal tumors and various other types of sarcoma.1
Skin Cancer Risk Factors and Symptoms
Risk factors and symptoms vary between different types of skin cancer, but can generally include:1
Risk Factors
- Ultraviolet (UV) radiation – Prolonged exposure to UV rays found in the sun or tanning lamps and booths is thought to be a major risk factor for melanoma and BCCs1
- Weakened immune system – Medications or conditions that suppress the immune system may increase the risk of skin cancer. For example, people taking corticosteroids or who have a weakened immune system may be at increased risk.1
- Previous skin cancer history – People who have had skin cancer before have a higher chance of developing another one1
- Skin color – light or fair skin color is associated with a higher risk for melanoma and other skin cancers1
Symptoms
- A new mole or lesion on the skin, or a mole that changes in size, shape, or color and looks different from other moles on the body1
- For Melanoma – warning signs can include one half of the mole looking different from the other half, irregular edges, different colors on a single mole, a very large mole, or one that is bleeding, oozing or swells4
- For BCC – flat, firm, pale areas of the skin or small, raised, pink or red, translucent, shiny, waxy skin areas that may bleed after a minor injury or visible abnormal blood vessels with discoloration on the skin or an oozing crusted area of the skin1
Early Stage Melanoma
Early Stage BCC
Early stage skin cancer looks like an abnormal mole or a lesion that is restricted to a small area of the skin.
Prevention
Because prolonged exposure to UV rays from sunlight increases the risk of getting skin cancer, the American Cancer Society recommends that skin should be protected from intense exposure by clothing, sunglasses and sunscreen that is a sun protection factor (SPF) of 15 or greater.3
Important Safety Information
TODO - code to include safety info from CMS
