Melanoma used to be rare; North Americas' lifetime risk of developing the disease was one in 1,500. But the incidence is on the rise - and it often targets healthy people in the prime of their lives.
Natalie Love was 24 and in the midst of wedding planning when she first noticed what she thought was a pimple on her temple. When it started changing size and colour over the next few months, she mentioned it to her doctor, who wasn't worried, so she didn't think it was urgent. She got married, she got pregnant—but she kept an eye on the blemish. "It was changing and growing even more," recalls Natalie, now a 41-year-old mom in Stonewall, Man. In fact, she realized that it was looking more like a mole.
Though her doctor still wasn't concerned, she did agree to refer her to a surgeon. Just after her first son was born in June 2001, Natalie went in to have the mole removed and biopsied. The diagnosis: melanoma. "I was shocked," she says.
More Than Skin Cancer
Simply calling melanoma "cancer of the skin" is a bit misleading. A more accurate description would be "starts in the skin, then can spread anywhere" cancer. It's a malignant tumour that originates in melanocytes, the cells responsible for making melanin, and can develop in weeks or take years to materialize. But if not caught, it "will start to invade," says Dr. Harvey Lui, head of the department of dermatology and skin science at The University of British Columbia and a dermatologist at BC Cancer Agency. "It will go deeper into the skin and reach a blood vessel, a nerve or the lymphatic system. That's when it can access the rest of your body."
Melanoma is the third most common type of skin cancer, and the most dangerous—and its incidence has been rising for decades.
In the 1930s, the lifetime risk of melanoma for North Americans was one in 1,500; now, it's one in 63. (Canadian women fare a little better than average, with a risk of one in 90.) The Canadian Cancer Society estimates that 6,800 people were diagnosed last year.
The steady upswing in melanoma comes down to sun safety. Although we all know to use sunscreen, many people are "half-hearted" about it, says Dr. Elaine McWhirter, a medical oncologist specializing in melanoma at the Juravinski Cancer Centre in Hamilton, an associate professor at McMaster University and a member of the Melanoma Network of Canada's board of directors. It's thought that about 90 percent of cases are related to UV exposure and a history of blistering sunburns.
UV exposure damages DNA in skin cells, causing genetic mutations that can lead to cells becoming cancerous. What's more, tanning beds—which the World Health Organization calls "carcinogenic"—remain readily accessible. Plus, even if Canadians are practising sun safety now, those who grew up before it was a public health concern can still develop cancer due to sun exposure in their youth.
Natalie says she was never a sunseeker, but sunscreen wasn't common when she was young, and on occasion she did get scorched. Because her melanoma was caught in Stage I, meaning it was less than one millimetre thick and hadn't broken open or spread, the treatment simply called for cutting it out, also known as a wide excision. "The surgeon was very positive. He said the likelihood of it coming back was slim," recalls Natalie, who went for post-surgery checkups for the next eight years. "I felt like I had dodged a bullet."
But one cruel characteristic of melanoma is how unpredictably it can behave. In 2008, she started getting what she thought were sinus headaches. They got progressively worse, until they were bad enough to cause blurred vision and make her vomit. A CT scan in December 2009 revealed a fist-size brain tumour. The cancer had spread, after all, and she needed surgery. "Initially, I thought, OK, they'll remove this, then I'll be fine. But I realized quickly that this cancer was going to keep coming back. I'm living with cancer, and it's not just going to be cured," says Natalie, whose cancer is now considered Stage IV, or metastatic melanoma
"It is rare to see very late recurrences," says Dr. McWhirter. "The majority of recurrences are within the first two to three years after surgery in those with higher risk melanoma." Yet, mysteriously, the disease can come back several decades after someone is seemingly cured, with no symptoms in between. It's called tumour dormancy. "A few microscopic cells may have escaped before the melanoma was cut out," Dr. McWhirter explains. "It's likely our immune system then keeps them in check for a long period of time."
This is what Natalie and her doctor suspect may have happened in her case: A few cancer cells were left behind; they lay dormant for years and then, for reasons unknown, woke up. (What ultimately reactivates the cancer cells is not fully understood.) Although the surgeon successfully removed Natalie's first brain tumour, she has developed new tumours since then, including spots on her lung, which were also surgically removed. There have been so many recurrences over the years, she hasn't kept count, and she's currently undergoing treatment for small tumours in her brain.
Dealing emotionally with melanoma has been "up and down, up and down," says Natalie, who keeps a blog on living with cancer (ithinkiwillgoforawalk.blogspot.ca). "But once I realized that this is sort of my job now, it was a bit easier. Some peace came with that."
If melanoma is caught early, it's considered very treatable. For those with Stage I disease, the five-year survival rate is 88 to 95 percent, says Dr. McWhirter. But if the cancer has spread, the outlook has historically been bleak. "In the old days, for incurable [Stage IV] melanoma, the five-year survival was about five percent," says Dr. Marcus Butler, a medical oncologist at the Princess Margaret Cancer Centre in Toronto. This was the case even a decade ago, says Dr. Mariusz Sapijaszko, an Edmonton-based dermatologist and president of the Canadian Dermatology Association.
But now, there's reason to feel more optimistic: In just the past few years, several groundbreaking treatments for Stage III or IV melanoma have been approved. "With these advances, the prospects for previously hopeless situations are better than ever before," says Dr. Sapijaszko.
These game-changers include immunotherapy drugs known as "checkpoint inhibitors," which unleash the power of our immune system. Normally, this system keeps us healthy by deploying T-cells, which go looking for things that don't belong; when an invader is found, our system ramps up to snuff it out, but then it winds down, so it's not in constant fight mode. What checkpoint inhibitors do is "take away the brakes, so the immune system doesn't turn off," says Dr. McWhirter. "We want it to recognize the melanoma cells so it can attack." There may be side-effects to these drugs, including joint pain, itching, thyroid dysfunction and less commonly serious problems in the lungs, liver or kidneys, but since the drugs are intended for advanced cases, the potential benefit outweighs the risk. The more effective of these drugs are pembrolizumab and nivolumab.
Another new approach to melanoma is called targeted therapy, which includes pairing medications like dabrafenib with trametinib. According to Dr. McWhirter, "combinations of targeted therapy are more effective and often have fewer side-effects." Whereas chemotherapy can kill even healthy cells, targeted therapy focuses on cancerous cells by zeroing in on what makes them different, such as an altered protein.
But what doctors find especially promising is combination therapy—such as using immunotherapy alongside targeted drugs, and combinations of checkpoint inhibitors—which has the potential to be more effective and to help patients live longer. Already, this two-in-one approach has seen great success; the survival rate for people with Stage IV melanoma in Canada is now 10 to 19 percent. "We have seen a dramatic increase in the percentage of people alive five years later," says Dr. Butler. " ‘Cure' is a word we're anxious about using, but we actually do have patients with Stage IV disease who look as if they're ‘cured.' "
Natalie's most recent scan showed that a couple of her brain tumours have shrunk. She's taking an immunotherapy drug and responding well. The cancer remains something she'll need to treat indefinitely, but at this point, it's a chronic illness, not a terminal one. She's grateful for the care she has received, and the breakthroughs that have saved lives like hers. "They didn't have these drugs a few years ago," she says. "It's pretty amazing."
Darker skin is safe from skin cancer. "Everyone is at risk for melanoma," says The University of British Columbia's Dr. Harvey Lui. A U.S. study published last year in the Journal of the American Academy of Dermatology found that while melanoma is most common in Caucasians, patients of colour (particularly African-Americans) were less likely to survive it.
SPF is the best way to protect against melanoma. Sunscreen is a must, but it's not all you should be doing. It's like safe driving, says Dr. Lui: "Just because you’re wearing a seatbelt doesn't mean you can drive like a maniac." You should still limit sun exposure, avoid midday UV (when rays are the strongest) and cover up with a hat and clothing.
If you don't get sunburned, there's no harm done. Even a tan is a sign of DNA damage that can lead to skin cancer. That's why the only safe bronze is faux. Furthermore, the DNA damage that can lead to skin cancer is caused by both types of rays—UVB (which cause burning) and UVA (which don't cause burning but are still destructive).
"A lot of melanomas are found by patients or their relatives, not by doctors," says Dr. Mariusz Sapijaszko, president of the Canadian Dermatology Association. Do a monthly check using the ABCDE method, and don't forget hard-to-see places like your back, a frequent site for skin cancer.
Melanomas are often lopsided; ordinary moles usually aren't.
Plain old moles typically have a smooth, distinct edge, while melanomas look more irregular and ragged.
Benign moles tend to be one even shade, whereas melanomas can have a mix of colours, such as red, grey, white, black and brown.
Melanoma lesions are often (though not always) more than six millimetres wide.
If a mole changes in colour, size, shape or symptom (like bleeding or feeling itchy), see a doctor. Can't memorize all the red flags? Remember this general rule: If one of your moles looks like an "ugly duckling"—different from the rest—get it checked out.