Skin Cancer: non-melanoma and melanoma

The skin is the body's largest organ. It protects against heat, light, injury, and infection. It helps control body temperature. It stores water and fat. The skin also makes vitamin D.

The skin has three main layers:

-              Epidermis: The epidermis is the top layer of the skin. It is mostly made of flat cells. These are squamous cells. Under the squamous cells in the deepest part of the epidermis are round cells called basal cells. Cells called melanocytes make the pigment found in skin and are located in the lower part of the epidermis.

-              Dermis: The dermis is under the epidermis. It contains blood vessels, lymph vessels, and glands. Some of these glands make sweat, which helps cool the body. Other glands make sebum. Sebum is an oily substance that helps keep the skin from drying out. Sweat and sebum reach the surface of the skin through tiny openings called pores. 

-              Hypodermis – which is fatty tissue

The skin cancer is the cancer that forms in tissues of the skin. When cancer arises from melanocytes it is called melanoma. When cancer arises from cells that do not make pigment it may begin in basal cells or squamous cells. Both types of skin cancer usually occur in skin that has been exposed to sunlight, such as the skin on the face, neck, hands, and arms. But skin cancer can occur anywhere.

Skin cancers are named for the type of cells that become cancerous.

Basal cell skin cancer grows slowly. It usually occurs on areas of the skin that have been in the sun. It is most common on the face. Basal cell cancer rarely spreads to other parts of the body.

Squamous cell skin cancer also occurs on parts of the skin that have been in the sun. But it also may be in places that are not in the sun. Squamous cell cancer sometimes spreads to lymph nodes and organs inside the body.

Risk Factors

   Studies have found the following risk factors for skin cancer:

-  UV radiation comes from the sun, tanning devices. A person's risk of skin cancer is related to lifetime exposure to UV radiation. Most skin cancer appears after age 50, but the sun damages the skin from an early age.  UV radiation affects everyone. But people who have fair skin that freckles or burns easily are at greater risk. These people often also have red or blond hair and light-colored eyes. But even people who tan can get skin cancer. People who live in areas that get high levels of UV radiation have a higher risk of skin cancer. Also, people who live in the mountains get high levels of UV radiation.  UV radiation is present even in cold weather or on a cloudy day.

-  Scars or burns on the skin

-  Exposure to arsenic at work

-  Chronic skin inflammation

-  Diseases that make the skin sensitive to the sun, such as albinism

-  Radiation therapy

-  Medical conditions or drugs that suppress the immune system

-  Personal or family history of  skin cancers

The best way to prevent skin cancer is to protect yourself from the sun. Also, protect children from an early age. Doctors suggest that people of all ages limit their time in the sun and avoid other sources of UV radiation.

It is best to stay out of the midday sun whenever you can. You also should protect yourself from UV radiation reflected by sand, water, snow, and ice. UV radiation can go through light clothing, windshields, windows, and clouds.

Wear long sleeves and long pants of tightly woven fabrics, a hat with a wide brim, and sunglasses that absorb UV.

Use sunscreen lotions. Sunscreen lotions may help prevent skin cancer, especially broad-spectrum sunscreen (to filter UVB and UVA rays) with a sun protection factor (SPF) of at least 15. But you still need to avoid the sun and wear clothing to protect your skin.

Symptoms

Most basal cell and squamous cell skin cancers can be cured if found and treated early. A change on the skin is the most common sign of skin cancer. This may be a new growth, a sore that doesn't heal, or a change in an old growth. Not all skin cancers look the same. Sometimes skin cancer is painful, but usually it is not. Checking your skin for new growths or other changes is a good idea.

The most common skin cancer symptoms are:

-  Small, pale lump

-  red lump

-  Sore or lump that bleeds or develops a crust

-  Flat red spot that is dry  may become itchy