Malignant melanoma is the most aggressive and life-threatening skin cancer. It develops in the cells that give the skin its colour (melanocytes) and has a very high tendency to spread to other areas of the body. The cure rates depend greatly on the stage of melanoma by the time of detection. Unlike many other types of cancer, melanoma strikes people of all ages groups, even the young.
Melanoma of the foot
Feet are one of the least cared for parts of the body, mostly ignored unless they cause a problem. Melanoma of the foot and ankle are often missed or diagnosed too late. This is especially true of melanoma arising within the nail unit or plantar (sole) surface, as they can be difficult to identify.
Most cases of melanoma are caused by too much exposure to ultraviolet (UV) rays from the sun or tanning beds. This exposure can include intense UV radiation obtained during short periods, or lower amounts of radiation obtained over longer periods.
Who can this affect?
Anyone can get melanoma, but some factors put a person at greater risk for developing this type of cancer. These include:
- Fair skin
- Blond, light or red hair
- Blistering sunburns before the age of 18
- Family history of melanoma
- Numerous moles, especially if they appeared at a young age
- Ultraviolet light exposure
What you should look for
Melanoma can occur anywhere on the skin, even in areas of the body not exposed to the sun. Melanoma usually looks like a spot on the skin that is predominantly brown, black, or blue—although in some cases it can be mostly red or even white.
There are four signs—known as the ABCDs of melanoma—to look for when self-inspecting moles and other spots on the body:
- Asymmetry: One-half of the lesion is not identical to the other, which means one half is different in shape from the other half
- Border: The lesion has an irregular, ragged, notched blurred or indistinct border
- Colour: The lesion is of more than one colour, rather than a single, solid colour
- Diameter: The lesion has a diameter greater than 6 mm is a cause of concern
- Evolution: The lesion changes in size, shape or colour
If any of these signs are present on the foot, it is important to see a foot care provider right away. It is also essential to see a MD if there is discolouration of any size underneath a toenail (unless the discolouration was caused by trauma, such as stubbing a toe or having something fall on it).
Precautions to avoid getting melanoma of the foot and ankle, as well as general precautions, include:
- Wear water shoes or shoes and socks. Flip flops do not provide protection!
- Use adequate sunscreen in areas that are unprotected by clothing or shoes. Be sure to apply sunscreen on the soles as well as the tops of feet.
- Inspect all areas of the feet daily, including the soles, underneath toenails, and between the toes.
- If you wear nail polish, remove it occasionally so that you can inspect the skin underneath the toenails.
- Avoid UV radiation during the sun’s peak hours (10 a.m. to 4 p.m.), beginning at birth. While sun exposure is harmful at any age, it is especially damaging to children and adolescents.
- Wear sunglasses that block 100% of all UV rays; both UVA and UVB.
- Wear a wide-brimmed hat.
Remember: Early detection is crucial with malignant melanoma. If you see any of the “ABCDE” signs or if you have discolouration beneath a toenail that is unrelated to trauma, consult your doctor as soon as possible.