Beach parties, lazy days at the pool, barbecues, picnics in the park, outdoor concerts. This is what summer fun means to many Americans. Getting that summer sun-kissed, bronze skin is often a point of pride and a sign of beauty and vigor for adults. But dermatologists are alarmed about the increasing rate of skin cancers in the U.S. Increased exposure to the sun directly correlates to an increased risk for skin cancer.
Dr. Bob Harper, a dermatologist with Marietta Dermatology & The Skin Cancer Center, said there’s no other type of cancer whose prevalence is increasing more rapidly than skin cancer.
“From 1970 to 2009, the incidence of melanoma increased by 800 percent among women and 400 percent among men,” Harper said. “More than 3 and a half million skin cancers will be diagnosed in 2 million people just this year. … There’s no other cancer in humans that has advanced at that accelerated a rate. You would think it’s probably because we are a sun-loving, sun-worshipping society and that’s what causes most of these. There are going to be almost 80,000 new cases of melanoma diagnosed in the United States this year. And unfortunately, almost 10,000 people will succumb to their melanoma.”
Medical communities are calling this an epidemic. But what exactly is skin cancer? Skin cancer refers to any cancer that begins in skin cells. Most cases are caused by over-exposure to UV rays from the sun or tanning beds. Treatment generally consists of surgical removal of cancerous cells. More aggressive and deadly types of cancer, such as malignant melanoma, are treated with a combination of surgery, chemotherapy and radiation.
Understanding skin anatomy is important to understanding skin cancer. Skin is a complex organ consisting of not just skin, but also hair follicles and sweat glands. It’s divided into two layers: An upper, thinner layer called the epidermis and a deeper, thicker layer called the dermis. Most ill effects from the sun take place in the epidermis because this layer is most exposed to sunlight and it takes a direct hit, leading to injury of the epidermis.
There are three types of skin cancer: Basal cell, squamous cell and melanoma.
Basal cell skin cancer
At the base of the border between the epidermis and the dermis sits the basal cells. These cuboidal cells lie at the base of the epidermis. As they migrate upward toward the surface, they flatten and mature into squamous cells. When they reach the top, they die and create a dry surface layer. Harper said he thinks of this as our plate of armor. This plate of armor is our first line of defense against germs and pathogens, and it helps prevent too much water loss. Skin also provides insulation, temperature regulation and sensation.
When a basal cell gets injured enough by sun damage, it turns into a basal cell skin cancer or basal cell carcinoma. Basal cell skin cancer is the most common type of skin cancer. While it rarely kills, basal cell skin cancer can cause disfigurement. According to the National Institutes of Health, about 80 percent of basal cell skin cancers occur on the head and neck, with the rest mainly on the trunk and lower limbs, particularly in women.
Basal cell skin cancer spots are shiny or pearly on the edge, Harper said. Crusting and bleeding in the center can frequently develop.
Squamous cell skin cancer
Squamous cell skin cancer develops the same way basal cell skin cancer does but it occurs in squamous cells. Its spots are often red and scaly. They can also have hard nodules and frequently look dome or horn-shaped. Often times, these areas bleed and fail to heal. Squamous cell cancer is the second most common skin cancer, but it is not nearly as dangerous as melanoma.
Malignant melanoma is the most deadly form of skin cancer.
“These are the big boys — the most serious,” Harper said.
In the basal layer, about every 8th or 10th cell is not a basal cell, but a sun tan cell. A sun tan cell is called a melanocyte. When a melanocyte becomes cancerous, it’s melanoma.
“Melanocytes make that color that we call a tan,” Harper said. “Technically the chemical is called melanin, but that’s what gives your skin a brown color when you’re out in sunlight. But these little melanocytes will only activate and generate that brown color if they get injured. So a tan is actually a sign of injury. Our society — our culture — thinks of a tan as being nice, sporty, outdoorsy, vigorous, maybe even quote ‘healthy.’ It’s become a symbol of summertime to come back from the beach with a tan. But it actually happens only because these little melanocytes are getting injured.”
According the American Family Physician group, malignant melanoma is responsible for 75 percent of all skin-cancer related deaths.
“When I went into practice in the early 1980s, your life chance of having melanoma was about 1 in 250, 270, something like that,” Harper said. “That was what we thought was a very large chance – an unacceptably large chance.”
In 2000, the rate jumped to 1 in 75 and in 2010 the rate was 1 in 50, Harper said.
ABC’s of spotting malignant melanoma
Suspicious spots and moles on the body that might be malignant melanomas can be spotted using the mnemonic “ABCDE.” A stands for asymmetric, B stands for border, C stands for color, D stands for diameter and E stands for evolving. Harper said E should also stand for extremely dark. These dangerous moles are often black in color.
“A black spot that sticks around that’s very, very uncharacteristically dark from the rest of your moles – get it checked,” Harper said, adding that melanomas can occur anywhere on the body. “Sometimes we refer to it as the ugly duckling sign — it just stands out from the rest of your moles.”
A malignant melanoma will appear asymmetrical. In contrast, a normal mole will be more evenly round or oval shaped.
The border of a malignant melanoma will appear irregular and jagged.
A mole that is more than one color is also suspicious. Normal spots are usually one hue.
The diameter should be no larger than the head of a pencil eraser or one-quarter of an inch.
If a mole evolves or changes shape over time, this is also suspicious and calls for a doctor’s appointment.
If any of these features are present in a mole that has recently appeared on the skin, the person should immediately get it checked by a dermatologist. If the doctor thinks the mole is suspicious, he or she will have it biopsied and sent for analysis. Most skin cancers spread slowly and are treatable and curable when caught early.
“Early detection is the name of the game,” Harper said.
But by being aware of suspicious moles and visiting a dermatologist, people can help keep their skin healthy and reduce their risk.