Mammography and Breast MRIs (Magnetic Resonance Imaging) are diagnostic screening tests used for detecting breast cancer. Each technology has its strengths and weaknesses. Here's some comparisons:
Mammography
Mammogram advantages:
- good at detecting DCIS (ductal carcinoma in situ)
- reliably detects calcifications
- widely available
- less expensive than MRI
- useful for women at any risk for breast cancer
- faster test than MRI (10 minutes or less)
Mammogram disadvantages:
- does not image well around implants
- compression of breast tissue (some discomfort)
- difficult to image dense breast tissue
- breast must be repositioned for different views
Breast MRI
Breast MRI advantages:
- more sensitive than mammograms, ultrasounds, and clinical breast exams
- useful for women at high risk for breast cancer
- finds invasive breast cancer well
- excellent at imaging around breast implants
- accurately images implant ruptures and leaked material
- no compression of breast tissue
- effectively images dense breast tissue
- helps evaluate inverted nipples
- finds primary tumor if cancer has spread to lymph nodes in armpit
- detects any remaining cancer after lumpectomy
- helps determine whether lumpectomy or mastectomy will be best treatment
- images both breasts simultaneously (useful for symmetrical comparison)
Breast MRI disadvantages:
- not good at detecting DCIS
- leads to many false-positive findings
- additional follow-up examinations and biopsies
- may not show all calcifications
- may cause claustrophobia
- requires use of injected contrast agent (Gadolinium)
- more expensive than mammogram ($100 vs $1000)
- not widely available
- slower than mammogram (30 – 60 minutes)
