Melanoma is a life-threatening type of skin cancer that can be treated if diagnosed early. Lesions can occur anywhere throughout the body, however, lesions arising on the bottom of the foot or the nail can be difficult to recognize. Melanoma is malignant cancer from the pigment-producing cells of the skin, called the melanocytes. There is a relationship between ultra-violet (UV) exposure and melanoma in sun-exposed areas. Caucasian populations have a much greater risk of developing the disease than those of Hispanic, Asian and Afro-Caribbean races. Non-caucasians overall have a much lower rate of the disease, however, these individuals can develop melanoma in areas such as the palms of the hands, the sole of the foot and the skin around the nails.
The skin lesions that melanoma arises from can be tan, brown, or black in color, and can be raised up or flat. In the nail, they can appear as streaks going down the length of the nail, but in many dark-skinned people, this is not abnormal.
During the colder months, many people switch to enclosed shoes and pay little attention to the skin on their feet. However, pigmented skin lesions can develop during this time of less exposure to the sun, and can be missed when one is not paying attention to their feet, unlike lesion on the face, arms, or trunk which are more visible on a daily basis. While the majority of these new skin lesion are benign, malignant melanoma and other sun-based skin cancers can develop. Unfortunately, some cases of melanoma can look like a small simple mole one would pay little attention to, and other forms lack any major pigment at all, making diagnosis difficult without a biopsy.
All pigmented or permanently discolored areas of the skin should be evaluated by a physician, whether they are new or old. Doctors are trained to look at features that can offer a glimpse as to whether the lesion should be investigated further. Our podiatrists routinely evaluate suspicious skin lesions on the feet and ankles, and we do catch lesions that have abnormal cells and cases that are malignant. The standard test to determine if the lesion is abnormal is a punch biopsy, in which the doctor gathers a very small plug of skin at the lesion site for a pathologist to evaluate under the microscope. This simple test can save a life.
If you notice or have noticed a discolored bump, patch of skin, or mole on your feet or ankles that does not go away in a couple of weeks, do yourself a favor and have one of our podiatrists take a look at it. Melanoma is not common, but occurs frequently enough and is deadly enough that close attention needs to be made to pigmented skin lesions. Of course, you should keep an eye on the rest of your skin as well, and see your family doctor or dermatologist if you notice something discolored or unusual.