Breast imaging is entering an exciting era, with many new applications to add to the standard mammogram and ultrasound exam. These techniques include breast tomosynthesis, breast scintimammography, and molecular imaging, such as breast-specific gamma imaging and PET. However, the application of MRI to breast imaging has gained the most acceptance and is rapidly disseminating into routine clinical practice.
Numerous studies have repeatedly demonstrated breast MRI to have a significantly greater sensitivity for breast cancer than conventional mammography, ultrasound, or physical exam. In some studies, the sensitivity approaches 100 percent (including DCIS). Like mammography, breast MRI suffers from a lack of specificity. The exact role of breast MRI in the detection and management of breast cancer is still under investigation. However, there are several well-established clinical applications of breast MRI.
Breast MRI versus Mammography
MRI imaging of the breast offers advantages and disadvantages over traditional mammography.
Mammography is relatively inexpensive and is widely available. There is mandated physician training and CME required to practice mammography. There is standardization for reporting and working up abnormal findings. Breast MRI is relatively new, with little individual or cumulative physician experience. However, the American College of Radiology has developed a lexicon of Breast MRI terminology to encourage standardization. All breast MRI exams are now reported using the BIRADS reporting system, which is familiar from mammography.
Mammography relies on significant breast compression (which can be quite uncomfortable) and standard X-ray technique. [Although the use of mammography is well accepted, there is an inherent risk of radiation-induced breast cancer with standard X-ray technique. This is particularly significant for younger patients who face many years of cumulative breast radiation exposure.] continued ...