To help find breast cancer early, you should begin by checking your breasts for lumps every month, beginning at about age 20. Your doctor can teach you how to check your breasts on your own. You should also have your doctor check your breasts every 1 to 2 years beginning when you're 30, and you should have a mammogram (an x-ray of your breasts) and a thermogram (a thermal image of the breast) every 1 to 2 years beginning at age 40. If you have risk factors for breast cancer, such as a family history, your doctor may want you to have mammograms/thermograms more often or start having them sooner.

To help find cervical cancer early, have regular Pap smears. During a Pap smear, your doctor takes a sample of cells from your cervix to be tested. You should have your first Pap smear when you start having sex or by age 18. Continue having a Pap smear once a year until you've had at least 3 normal ones. After this, you should have a Pap smear at least every 3 years, unless your doctor suggests that you need one more often. Keep having Pap smears throughout your life, even after menopause.

To help find prostate cancer early, first talk to your doctor about your risk. Doctors don't all agree on whether screening is needed for men who aren't at high risk of prostate cancer.

The National Cancer Institute, the American Cancer Society, the U.S. Preventive Services Task Force and the American Academy of Family Physicians recommend that men talk to their doctors about whether screening is needed.

Your doctor may examine your prostate by putting a gloved, lubricated finger a few inches into your rectum to feel your prostate gland. This is called a digital rectal exam. A normal prostate feels firm and rubbery. If there are hard spots on the prostate, your doctor may suspect cancer.

Another way to check for prostate cancer is with a blood test called the PSA test. PSA is short for prostate-specific antigen. Men who have prostate cancer may have a higher level of PSA in their blood. However, the PSA level can also be high because of other, less serious causes such as infection.

To help find testicular cancer early, examine your testicles on a routine basis. If you find anything unusual during a self-exam (like a lump or swelling), see your doctor right away. The best time to do the exam is during or right after a shower or a bath. The warm water relaxes the skin on your scrotum and makes the exam easier. Your doctor can give you more specific information about checking your testicles.

Most colorectal cancers begin as a polyp (say “pahl-ip”). At first, a polyp is a small, harmless growth in the wall of the colon. However, as a polyp gets larger, it can develop into a cancer that grows and spreads. See your doctor if you have any of the following warning signs:

• Bleeding from your rectum
• Blood in your stool or in the toilet after you have a bowel movement
• A change in the shape of your stool
• Cramping pain in your lower stomach
• A feeling of discomfort or an urge to have a bowel movement when there is no need to have one

A digital rectal exam is usually used along with another screening test to check for colorectal cancer. Tests used to screen for colorectal cancer include the following:

• Fecal occult blood test (in which your stool is checked for blood that you can't see)
• Flexible sigmoidoscopy (in which a tiny camera is inserted into your colon, allowing your doctor to look at the rectum and the lower part of your colon)
• Double-contrast barium enema (for which you take an enema and have an x-ray to find abnormal spots)
• Colonoscopy (similar to a flexible sigmoidoscopy, except the entire colon is examined)

Colorectal cancer is more common in older people, so doctors usually screen people after the age of 50 years. Some people have risk factors that make them more likely to get colorectal cancer at a young age. Screening should begin earlier in these people.

Talk to your family doctor to decide which screening tests you should have and how often you should be screened.

The best way to find skin cancer early is to keep an eye on your skin, especially moles. The ABCDE rule (see below) can help you remember what to look for when you're checking any moles on your skin. If you notice any of these signs, talk to your doctor right away.

Signs of skin cancer: The ABCDE rule

 A for asymmetry: A mole that, when divided in half, doesn't look the same on both sides.

 B for border: A mole with edges that are blurry or jagged.

 C for color: Changes in the color of a mole, including darkening, spread of color, loss of color, or the appearance of multiple colors such as blue, red, white, pink, purple or gray.

 D for diameter: A mole larger than 1/4 inch in diameter.

 E for elevation: A mole that is raised above the skin and has an uneven surface.