Follow-up of women with breast cancer: comparison between MRI and FDG PET.

The aim of this study was to compare MRI of the breast with 18F-fluoro-deoxy-glucose (FDG) positron emission tomography (PET) in patients with suspected local or regional breast cancer recurrence or suspected contralateral breast cancer. Thirty-two patients (mean age 57.2 years, age range 32–76 years) with suspected loco-regional recurrence (n=19), chest wall recurrence (n=5), and suspected secondary tumor of the contralateral breast (n=8) underwent MRI of the breast and FDG PET of the whole body and breast region. Cytology/histology (n=17) or a clinical follow-up examination (n=15) with additional imaging served as the standard of reference. A McNemar test was performed to compare PET and MRI, and kappa was determined to quantify agreement of both methods. Sensitivity was 79 and 100%, specificity was 94 and 72%, and accuracy was 88 and 84% for MRI and PET, respectively. Additional metastases outside the field of view of MRI were found in PET in 5 patients. In this study both imaging methods had comparable accuracy. The detection of distant metastases with whole-body PET imaging can influence patient management.