1. Department of Radiology and Center for Breast Cancer, National Cancer Center, Goyang-si 410-769, Korea.
2. Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.
3. Department of General Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.