This review describes the current knowledge and challenges of breast cancer
staging and screening with MRI of the breast. Assessment of local disease
extent, including tumor size, multicentricity, and chest wall invasion, can
be obtained more accurately with MRI than with mammography. Moreover, inte
rnational experts have established standardized reporting of MRI staging re
sults, taking into account tumor size measurements and the number of breast
quadrants involved. Results from MRI assessment of the axilla and skin are
promising, but need further refinement. Preliminary results of the use of
breast MRI in patients at high risk for breast cancer demonstrated a superi
ority of breast MRI over the combined use of mammography and high-frequency
ultrasound. The role of MRI in this subset of patients may be confirmed by
ongoing larger multicenter trials. Strict protocol conditions are mandator
y to maintain a high standard of quality. Confirming the nature of "MRI-onl
y" lesions with MRI-guided biopsy systems will allow changes in treatment p
lanning. More accurate tumor diagnosis and tumor volume evaluation may allo
w minimally invasive treatment strategies. (C) 2001 Wiley-Liss, Inc.