1. Department of Internal Medicine, Center for Breast Cancer, Hospital, National Cancer Center, 323 Ilsanro, Goyang 10408, Republic of Korea
2. Cancer Data Center, National Cancer Control Institute, National Cancer Center, 323 Ilsanro, Goyang 10408, Republic of Korea
3. Division of Rare and Refractory Cancer, Research Institute, National Cancer Center, 323 Ilsanro, Goyang 10408, Republic of Korea
4. Department of Pathology, National Cancer Center, Hospital, 323 Ilsanro, Goyang 10408, Republic of Korea
5. Department of Surgery, Center for Breast Cancer, Hospital, National Cancer Center, 323 Ilsanro, Goyang 10408, Republic of Korea
6. Division of Clinical Research, Research Institute, National Cancer Center, 323 Ilsanro, Goyang 10408, Republic of Korea
7. Center for Proton Therapy, National Cancer Center, 323 Ilsanro, Goyang 10408, Republic of Korea