Is it true that breast lump or tumor have been in your breast for a year or two and a mammogram can see them?

Yes, even longer: Yes, actually breast cancer begins as a single cell and probably requires 10 years of growth to become approximately 1 cm in size. This is when it will first be revealed during an exam by the doctor. While a mammogram may pick it up slightly sooner it is certainly the fact that the mass has been there for many years prior to its discovery with mammographic imaging.

Yes.: A breast lump can be seen as small as 3 or 4 mm in a fatty breast , but may be larger before it is discovered in a dense breast, as most breast lumps of concern are of similar density to glandular tissue. The benefit of a mammogram is to find a cancer prior to it becoming palpable to you or your doctor.

Yes: Some breast tumors, even cancers, are slowly growing and may have formed a year or even two before it became large enough to bee seen. It may be easier to understand this by knowing that a tumor the size of a small pea already has over a billion cells it.

Yes,: cancers begin at the cellular level and may take several years before they get large enough to be visualized on a mammogram.