Some of the most dangerous places skin cancer can occur are on the bottom of feet, between toes and under toenails.When board-certified dermatologist Dr. Elizabeth Tanzi was pregnant with her first child, a dark spot formed on her lower leg. Six months later, when the spot began to grow, the alarm bells started ringing.
“As a dermatologist, I knew that any change in a mole could indicate developing cancer, so I had it biopsied, and it was a melanoma,” she said. “I was 37 at the time and extremely worried, but the surgeon was able to remove it completely.”
Skin cancer is one of the most common forms of cancer, with over 9,000 Americans being diagnosed with the disease every day. Healthy sun safety practices, monthly self-checks and being cognisant of the ABC’s of skin cancer (asymmetry, border, colour, diameter and evolving) are always good ideas, but dermatologists warn that there are other things to consider that people might find surprising.
Though reggae music pioneer Bob Marley died of melanoma that started underneath his toenail, the nails are still an area where cancer often goes undetected.
“We most commonly see squamous cell carcinoma and melanoma under the nail,” explained Dr. Jennifer Holman, a board-certified dermatologist with U.S. Dermatology Partners Tyler. “Squamous cell carcinoma presents much like a wart under the nail, while melanoma presents as new, irregular or changing pigment streaks along the nail and cuticle.”
The problem with this location is that it closely resembles a bleeding wart, bruise or fungal infection, and many people don’t realise it could be something more serious. For this reason, cancer that forms under the nail can have a very poor prognosis, Tanzi said.
Holman, who was diagnosed with melanoma after noticing a changing mole on her stomach, attributes her diagnosis to her use of heavy indoor tanning in college.
“We know that even a single indoor tanning exposure can exponentially increase the risk of melanoma, and that women under 30 are six times more likely to develop early onset melanoma if they are indoor tanning users,” Holman said.
The reason? According to Holman, indoor tanning typically involves concentrated UVA radiation, which specifically increases the risk of melanoma.
“We typically think of UVB as the rays that cause sunburns, but UVA penetrates more deeply and increases that risk,” she said. “Skin cancer incidence is higher than that of any other human malignancy, and yet one of its root causes (ultraviolet radiation) is perhaps better understood than any other human carcinogen.”
Though uncommon, getting skin cancer in between your toes is a possibility — and a dangerous one, at that.
“Melanoma, when caught early, has a very good cure rate, however, when it’s allowed to progress and spread down into the skin, it can be deadly,” Tanzi said. “Since people may not notice a changing mole between their toes or on the bottom of the foot, melanoma in these areas is particularly dangerous because it goes undetected for long periods of time and is allowed to spread.”
According to the American Academy of Dermatology, about half of melanomas are self-diagnosed — so if you notice a spot of concern, have it checked out by a board-certified dermatologist.
The most common forms of skin cancer are basal cell carcinoma, squamous cell carcinoma and melanoma. While the first two types are associated with sun exposure, melanoma can occur in some circumstances even without the sun.
“I hear patients describe basal and squamous cell carcinomas as a spot that bleeds more easily,” Holman said. “Typically, patients think they have a pimple, inflamed hair follicle or bug bite when [it forms], but they don’t heal and continue to grow and bleed.”
Remember that skin lesions that bleed or don’t heal over time are never normal, and can be a big red flag for possible skin cancer.
Just say no to tanning beds.While dermatologists typically use the ABCDE rules for evaluating changes to your skin — spots that become Asymmetric, have an irregular Border, new or changing Colours, a Diameter greater than a pencil eraser, or seem to be Evolving — this isn’t true of all melanomas, Holman said.
“Sometimes they don’t even have any pigment at all — the main thing to look out for is any spot, even if you aren’t sure how long it’s been present, that’s changing or doesn’t heal after a few weeks.”
Early diagnosis is crucial for both the cosmetics of the scar left behind and the overall survival rate of the patient.
Especially in the early stages, skin cancer can resemble benign skin conditions like eczema or psoriasis. Unfortunately, this similarity can lead to misdiagnosis or delayed diagnosis.
“I have patients come to me thinking they have a patch of eczema or psoriasis, but they can actually be a superficial basal or squamous cell,” Holman said. “Both psoriasis and eczema (atopic dermatitis) can present as red, scaly patches, but if an area is unresponsive to traditional treatments or doesn’t heal or go away after a few weeks, it should be evaluated by a board-certified dermatologist.”
While people with fairer skin types are more likely to get skin cancer, people of all skin tones are at risk for skin cancer, even those with darker skin.
Holman, who recently did a melanoma excisional surgery on a woman with the darkest skin type, said that unfortunately, melanoma is less suspected and therefore often detected later in darker skin types.
“About the same number of Caucasians and African Americans develop melanoma on the feet while Asian and African Americans most often develop melanoma on the hands and feet,” Holman said. “This is why there is a higher morbidity and mortality rate for melanoma in darker skin tones, as melanoma on the bottom of the feet, between the toes and under the nails is often detected at a later stage and as a result, can carry a higher risk.”
