Sunlight is the leading cause of melanoma, so most people only check their body for skin cancer in areas that receive a lot of sunlight. However, new research suggests that there’s one place where the sun rarely shines that you should regularly check for melanoma.
That place is the bottom of your feet. While sunlight may be the leading cause of skin cancer, there are other common causes that can contribute to melanoma development. Daily tear and wear may contribute to skin cancer development, and no area of are body takes as regular a beating as our feet. According to Japanese researchers, melanomas on the soles of the feet tend to develop in areas that receive the most stress when people walk or run, so the ball, heel and arch of your foot are all susceptible to melanoma,
“Our clinical observation suggests that mechanical stress — such as plantar pressure and shear stress — is involved in the development of melanoma on the sole,” said senior researcher Dr. Ryuhei Okuyama of Shinshu University School of Medicine in Matsumoto, Japan.
Okuyama added that because people rarely check the underside of their feet, cancers found in these locations are often in a more advanced stage that other cancers, which can have deadly consequences.
Skin Cancer and Your Feet
The good news is that melanoma development is rather rare. Only 1 percent of all skin cancers are melanomas, but they are the most deadly form of cancer. The American Cancer Society expects roughly 76,000 Americans to be diagnosed with melanoma this year, and approximately 10,000 will die from the cancer.
Melanoma development on the feet is even rarer, as they account for about 2.3 cases out of a million in the United States, but as we mentioned above, oftentimes they aren’t caught until the damage has been done. Only about 40 of the 123 patients reviewed for a study of melanomas on the underside of the foot had a cancer that was 1 millimeter or less thick, which is much lower than the national average for skin cancers on other areas of the body.
“Once you get above that 1 millimeter level, you can be in serious trouble,” said Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society.
The most common locations were on the sole and ball of the foot, where pressure is regularly placed while walking. Fewer instances were reported on the arch, which receives little pressure when walking, but still plays a crucial role in movement. Dr. Lichtenfield said the study findings were interesting, but it doesn’t necessarily prove that excess wear and tear will lead to melanoma development.
“The authors have provided us with useful and thought-provoking information, but whether stress is the cause of melanoma in these locations is unknown,” he said. “It’s unlikely this is the complete story about why these melanomas happened in the first place. There may well be other factors involved.”
Regardless of whether pressure on your feet can lead to melanoma development, one thing is clear – Doctors and patients need to be checking feet regularly for lesions or moles.
“In our view, a foot check should be considered as a part of skin cancer exam, especially in elder persons,” concluded Dr. Okuyama. “Lesions on the sole are hardly noticed in daily life.”
