Which Cancer Tests Do You Really Need? Feb. 1, 2013 -- Not all cancer screening tests are helpful, and some are potentially harmful, according to a new Consumer Reports rating.

In the new report, Consumer Reports recommends only three of 11 common cancer screening tests, and then only for certain age groups.

Screenings for cervical, colon, and breast cancer are recommended.

Screenings for cancers affecting the bladder, lungs, skin, mouth, prostate, ovaries, pancreas, and testicles are not.

"The science of prevention and screening has changed," says John Santa, MD, MPH, director of the Consumer Reports Health Ratings Center. He oversaw the project.

"Consumers need to know that some screening tests are terrific, some are not good, and some can harm you," Santa says.

"We are not talking about people at high risk," he says. "And of course they are not symptomatic. We're not talking about what you should do if you have a mole that is changing or if you feel a breast lump."

The full report is in the March issue of Consumer Reports.

Slideshow: Top Cancer-Fighting Foods