Thermograms are tests that measure heat patterns in the breasts on the assumption that breast cancers give off more heat than surrounding tissue. It is not reliable and should definitely not replace mammograms.
Blood tests for tumour markers are also not a reliable way to pick up breast cancers
Thermograms: Although cancers do theoretically generate more heat than surrounding tissue, this is not universally true. Thermograms are insufficiently accurate to be used as a screening or diagnostic test for breast cancer. Many of the promises made about thermography are misleading. Don’t trust your life to thermography or any other unproven test, no matter the hype and supposed safety.