Several basic self-exams are available that help in the early detection of some serious diseases such as breast cancer, testicular cancer, and skin cancer. For skin cancer (melanoma), the ABCD rule is a convenient guide to the usual signs of melanoma. Be on the lookout and notify your doctor about any of the following changes to a mole or birthmark:
- A is for asymmetry: One-half of a mole or birthmark does not match the other.
- B is for border: The edges are irregular, ragged, notched, or blurred.
- C is for color: The color is not the same all over, but may have differing shades of brown or black, sometimes with patches of red, white, or blue.
- D is for diameter: The area is larger than 6 millimeters (about ¼ inch—the size of a pencil eraser) or is growing larger.
The most important warning sign for skin cancer is a spot on the skin that is changing in size, shape, or color over a period of one month to two years.
