The goal is for all people with breasts to have more knowledge on their options when it comes to breast health screenings.
The hope is by providing this information, you can make the best-informed decision for your own body and your own health.
The vision is empowered patient-centered advocates for 'Best Practices' (which is not the same as 'standard of care').
When screening/detecting cancer, earlier is always better.
A typical mammogram is the oldest of screening tools, and a limited one. For a comparison of breast screening methods, go to independent site DenseBreast-info.org.
Not all breast cancer is the same: The two current 'main' types of are Ductal (now also known as NST - No Specific Type) and Lobular.
You're probably familiar with NST/ductal breast cancer, which typically presents as a 'lump'. But for dense breast tissue it's routine for mammograms to miss lumps in the early stages, when they're easiest to treat.
For lobular cancer, it is routine for mammograms to miss lesions at even later stages, when they're even harder to treat.
Screening mammograms routinely miss early NST/Ductal cancer in dense breasts. Check out the EXCELLENT video from independent site DenseBreast-info.org about dense breast mammogram 'masking' (watch how difficult it is to see lump in slides C and D).
Because of these imaging issues, several states have already made breast density reporting to patients a requirement. Not sure of your status? Find out more at the independent site Dense Breast-Info.org.
So What's the difference?
The two machines use different technology, which results in difference in their accuracy and in what they can see. A mammogram is more likely to give you a false-negative: false-meaning the result looks normal even though breast cancer is present, causing delay in detection and treatment.
The other possible kind of "incorrect" result is a false-positive. A false-positive result looks abnormal even though there is no cancer in the breast. It requires more testing to confirm or rule out and monitoring in the future.
MRI's have a much lower rate of false-negatives, and a similar rate of false-positives.
With just a mammogram you could have cancer and not know for years (routine for lobular cancer). Even if an MRI gives a false positive - it can be stressful, but another test can quickly confirm or rule out cancer. Which would you rather have happen to you?
Read below for more details.
Overall, screening mammograms miss about 1 in 8 breast cancers. (12.5%) Women with dense breasts or lobular cancer are more likely to get false-negative results. False-negative mammograms can give women a false sense of security, thinking that they don’t have breast cancer when in fact they do (mammograms have the highest false negatives all screening methods).
A false-positive mammogram looks abnormal even though there is no active cancer in the breast. Abnormal results often require extra testing (MRI, diagnostic ultrasound or even a breast biopsy) The false positive rate for mammograms is 7-12% (and is the lowest of all screening methods).
Ductal Breast Cancer
Mammograms routinely miss NST/ductal lesions in the early stages if 'masked' by any dense tissue, causing delay in treatment ad harsher treatments.
Lobular Breast Cancer
Mammograms routinely miss lobular cancer.
Overall: Less false negatives, more sensitive screening (earlier detection), fine for dense breasts, routinely detects lobular cancer
A false positive result looks abnormal even though there is no cancer in the breast. Abnormal results often require extra testing (diagnostic ultrasound or even a breast biopsy) to find out if the change is cancer. A false-positives are often cited as the "problem" with MRI. Recent studies and improvements have changed this. The false positive rate for MRI is 5-8%.
Ductal Breast Cancer
MRI are more sensitive than mammograms and can detect small ductal cancers earlier (when they are more treatable), even through dense tissue.
Lobular Breast Cancer
MRI's can see the changes in breast tissue that indicate lobular cancer.
MRI's are more accurate, and can see through dense tissue, where mammograms routinely cannot.