evidence: One fact remains clear: Mammography is still the best tool available to screen for breast cancer, with research showing it has lowered the number of breast cancer deaths by 40% since 1990. Myth #6: Mammograms don’t reduce deaths from breast cancer. [...] But one fact remains clear: Mammography is still the best tool available to screen for breast cancer, with research showing it has lowered the number of breast cancer deaths by 40% since 1990.