A little-known sign of "aggressive" cancer appears in the nails

Our bodies have clever ways of telling us something is wrong, from showing physical symptoms, such as headaches and a runny nose, to unusual symptoms that prompt us to seek medical advice.

Our nails may be one of the ways the body uses to inform us of a disturbing health risk, as they can show symptoms of different types of cancer, including cancer under the skin, or as it is also called melanoma under the nails.

However, this condition is rare and accounts for 0.7% to 3.5% of all melanomas worldwide, according to the Cleveland Clinic.

The health website explains that it is most likely to develop in the big toe, thumb, or index finger.

The clear sign of this type of cancer is the presence of a dark vertical line on the nail, which is also known as a subungual lesion. It resembles a bruise under the nails, and is usually located along the lower edge of the nail, near the cuticle.

This dark line or stripe may start small but eventually grow to cover your entire nail. The colored line is usually less than three millimeters long, but may become wider over time.

Furthermore, the color change can be irregular and have different shades of blackish-brown. However, there are also cases in which subungual melanoma does not change the color of the nail, and instead, warning signs can be detected in the form of a small, irregularly shaped growth that can lift the nail.

The Cleveland Clinic website adds that melanoma under the nail may also cause:

- Split, cracked, or otherwise deformed nail.

- Irregular pigmentation (color change is not uniform).

- Swollen or inflamed nail.

- An ulcer appears or bleeding begins.

- Change in color of the skin surrounding the nail.

While all of these signs could indicate skin cancer, the American Cancer Society explains that some non-cancerous conditions and medications can cause these problems as well, so it will be "important to talk with your doctor about all medical problems you may have and about medications, vitamins, and minerals." "And the supplements you're taking so your risks can be discussed and you know what to expect."