Digital infrared thermal imaging is an ideal way to screen for breast cancer.
Since it is totally non-invasive, it can be used safely at any age. The denser breast tissue before menopause that makes standard mammograms difficult do not pose any problems for thermograms. Thermal imaging can often pick up changes well before they become clear on other screening methods.
Inflammatory breast cancer, a more aggressive form of breast cancer that can't be picked up by mammograms, can be readily detected by thermography.
Thermal imaging is best used in conjunction with mammography, and can also be used when mammograms aren't tolerated or otherwise feasible.
Here is a collection of images so you can see samples of what will turn up with digital infrared thermal imaging:
Flash (put pointer on images to see captions) or (same pictures) gallery.

With strict standardized interpretation protocols having been established for over 15 years, infrared imaging of the breast has obtained an average sensitivity and specificity of 90%. As a future risk indicator for breast cancer, a persistent abnormal thermogram caries a 22 times higher risk and is 10 times more significant than a first order family history of the disease. Studies clearly show that an abnormal infrared image is the single most important risk marker for the existence of or future development of breast cancer.

-The Biomedical Engineering Handbook, Third Edition, Medical Devices and Systems published by CRC Press, 2006.

Dr. Sherri Tenpenny DO maintains an informative blog about breast health, click here to visit it.

Click here (or here) for the transcript and video (though the video seems to be down) of a news segment on thermography from KAKE news in Kansas. Here is a transcript and video of a news story from WHDH in Boston.
Here's a video about breast thermography I came across on YouTube (be warned that the videography is a bit dizzying):