Skin cancer is the most common of all cancers. About 3.5 million cases of basal and squamous cell skin cancer are diagnosed in the United States each year. Melanoma, a potentially more dangerous type of skin cancer, will account for more than 73,000 cases of skin cancer in 2015.
What are basal and squamous cell skin cancers?
These types of skin cancer start in the basal cells or squamous cells of the skin, which is how they get their names. These cells are found in the epidermis, the upper layer of the skin. Most basal and squamous cell cancers develop on sun-exposed areas of the skin. These most common types of skin cancer may also be referred to as "non-melanoma skin cancer" or "keratinocyte carcinoma."
Basal cell carcinoma (BCC) accounts for approximately 75% of all skin cancer. It tends to grow slowly and very rarely spreads to other parts of the body. Left untreated or undetected, however, it may grow into the surrounding tissue. It may even grow into cartilage or bone. Rarely, it may track along nerves or blood vessels.
Squamous cell carcinoma (SCC) is the second most-common type of skin cancer. It is somewhat more likely to grow into deeper layers of skin and to spread, although this is still not common. It may at times grow rapidly. Like basal cell carcinoma, it may at times grow along nerves or blood vessels and will invade into any surrounding tissue. Approximately 4% of squamous cell carcinoma will metastasize (spread to lymph nodes or internal organs).
Both basal cell and squamous cell skin cancers can be readily cured if found and treated early.
What is melanoma skin cancer?
Melanoma is a cancer that begins in the melanocytes – the cells that make the brown skin pigment known as melanin, which gives the skin its color. Melanin helps protect the skin from the harmful effects of the sun's ultraviolet rays. Melanoma can start on nearly any part of the skin, even in places that are not normally exposed to the sun, such as the genital or anal areas. Melanoma is almost always curable when found in its very early stages. Although melanoma accounts for only a small percentage of skin cancers, it’s more likely to grow and spread to other parts of the body, where it can be hard to treat. Because of this, melanoma causes most skin cancer deaths, accounting for nearly 10,000 of the more than 13,000 skin cancer deaths each year. There recently have been incredible advances in medical oncology for metastatic melanoma, which will hopefully improve survival of those affected by metastatic disease.
Other types of skin cancer
There are many other rare types of skin cancer, such as Merkel cell carcinoma, cutaneous lymphoma, skin adnexal tumors, and sarcomas. These are all much less common than non-melanoma skin cancer or melanoma.
What are the risk factors for skin cancer?
Risk factors for skin cancer include:
Ultraviolet (UV) radiation (from sunlight or tanning beds and lamps)
Fair skin (easily sunburned, doesn’t tan much or at all, natural red or blond hair)
Light colored eyes
Previous history of skin cancer
Family history of skin cancer
Multiple or unusual moles
Severe sunburns in the past
Weakened immune system
Exposure to large amounts of coal tar, paraffin, arsenic compounds, or certain types of oil
What are the signs and symptoms of skin cancer?
Skin cancer can be found early, and both people and their doctors play important roles in finding skin cancer. If you have any of these symptoms, see a doctor:
Any change on your skin, especially in the size or color of a mole, growth, or spot, or a new growth (even if it has no color)
Scaliness, roughness, oozing, bleeding, or a change in the way an area of skin looks
A sore that doesn’t heal
The spread of pigmentation (color) beyond its border, such as dark coloring that spreads past the edge of a mole or mark
A change in sensation, such as itchiness, tenderness, or pain
The best ways to lower your risk of skin cancer are to avoid long exposure to intense sunlight and practice sun safety. You can still exercise and enjoy the outdoors while using sun safety at the same time. Here are some ways to be sun safe:
Seek shade, especially in the middle of the day (between 10 am and 4 pm) when the sun’s rays are strongest. Teach children the shadow rule: if your shadow is shorter than you, the sun’s rays are at their strongest. In Florida in particular, intensely strong sunlight may occur most of the day, before 10 am and beyond 4 pm.
Follow the Slip! Slop! Slap! and Wrap! rules:
Slip on a shirt: Cover up with protective clothing to guard as much as possible when you’re out in the sun. Choose comfortable clothes made of tightly woven fabrics that you can’t see through when held up to a light. You can find clothing with sun protection now, or even add SPF it to your laundry (Sun-Guard).
Slop on sunscreen: Use sunscreen and lip balm with broad spectrum protection and a sun protection factor (SPF) of 30 or higher. Apply a generous amount of sunscreen (about a palmful) to all areas of unprotected skin. Reapply every 2 hours and after swimming, toweling dry, or sweating.
Slap on a hat: Cover your head with a wide-brimmed hat, shading your face, ears, and neck.
Wrap on sunglasses: Wear sunglasses with 100% UVA and UVB absorption to protect your eyes and the surrounding skin.
Sunscreen doesn’t protect from all UV rays, so don’t use sunscreen as a way to stay out in the sun longer.
Follow these practices to protect your skin even on cloudy or overcast days. UV rays can travel through clouds.
Avoid other sources of UV light. Tanning beds and sun lamps are dangerous. They damage your skin and can cause cancer. Tanning beds have now been categorized as a human carcinogen by the World Health Organization (WHO), just like cigarettes.