1Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea
2Department of Radiation Oncology, Ewha Womans University College of Medicine, Seoul, Korea
3Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
4Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea
5Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Korea
6Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
7Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
8Proton Therapy Center, National Cancer Center, Goyang, Korea
9Department of Radiation Oncology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
10Department of Radiation Oncology, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
11Department of Radiation Oncology, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Korea
12Department of Radiation Oncology, Chungnam National University College of Medicine, Daejeon, Korea
13Department of Radiation Oncology, Gyeongsang National University School of Medicine and Gyeongsang National University Changwon Hospital, Changwon, Korea
14Department of Radiation Oncology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun, Korea
15Department of Radiation Oncology, Dongnam Institute of Radiological and Medical Sciences, Busan, Korea
16Department of Radiation Oncology, Yangsan Pusan National University Hospital, Pusan National University School of Medicine, Yangsan, Korea
17Department of Radiation Oncology, Korea University Ansan Hospital, Korea University College of Medicine, Asan, Korea
18Department of Radiation Oncology, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea
19Department of Radiation Oncology, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju, Korea
20Department of Radiation Oncology, Chosun University Medical School, Gwangju, Korea
21Department of Radiation Oncology, Seoul National University Bundang Hospital, Seongnam, Korea
Copyright © 2022 by the Korean Cancer Association
This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Ethical Statement
This study was approved by the institutional review board of each institution. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Because of the retrospective design of the analysis, requirement for obtaining informed consent of participants included in the study was exempted.
Author Contributions
Conceived and designed the analysis: Kim K, Kim IA.
Collected the data: Jung W, Shin KH, Im SA, Kim HJ, Kim YB, Chang JS, Kim JH (Jee Hyun Kim), Choi DH, Park YH, Kim DY, Kim TH, Choi BO, Lee SW, Kim S, Kwon J, Kang KM, Chung WK, Kim KS, Nam JH, Yoon WS, Kim JH (Jin Hee Kim), Cha J, Oh YK.
Contributed data or analysis tools: Kim JS, Kim K, Kim IA.
Performed the analysis: Kim JS, Kim K.
Wrote the paper: Kim JS, Kim K.
Writing-review and editing: Kim JS, Kim K, Jung W, Shin KH, Im SA, Kim HJ, Kim YB, Chang JS, Kim JH (Jee Hyun Kim), Choi DH, Park YH, Kim DY, Kim TH, Choi BO, Lee SW, Kim S, Kwon J, Kang KM, Chung WK, Kim KS, Nam JH, Yoon WS, Kim JH (Jin Hee Kim), Cha J, Oh YK, Kim IA.
Conflicts of Interest
Conflict of interest relevant to this article was not reported.
Characteristic | 2005–2008 (group I) | 2009–2011 (group II) | 2012–2014 (group III) | p-value |
---|---|---|---|---|
No. of patients | 98 | 200 | 302 | |
Age at primary BC (yr) | 45.1 (39.2–51.9) | 45.5 (37.8–52.8) | 48.1 (41.8–53.7) | 0.019 |
Age at BM (yr) | 49.0 (41.4–56.1) | 48.3 (39.8–56.2) | 51.2 (45.6–57.4) | 0.008 |
Interval of primary BC and BM (mo) | 30.6 (14.4–48.9) | 29.4 (16.5–56.4) | 34.2 (19.2–54.0) | 0.482 |
Tumor subtype | ||||
HR+/HER2− | 17 (17.3) | 54 (27.0) | 96 (31.8) | 0.082 |
HER2+ | 46 (46.9) | 87 (43.5) | 126 (41.7) | |
Triple-negative | 35 (35.7) | 59 (29.5) | 80 (26.5) | |
Initial BC stage | ||||
Stage I | 11 (11.2) | 17 (8.5) | 28 (9.3) | 0.092 |
Stage II | 39 (39.8) | 56 (28.0) | 99 (32.8) | |
Stage III | 35 (35.7) | 70 (35.0) | 94 (31.1) | |
Stage IV | 13 (13.3) | 57 (28.5) | 81 (26.8) | |
ECOG | ||||
0–1 | 69 (70.4) | 130 (65.0) | 197 (65.2) | 0.601 |
2–3 | 29 (29.6) | 70 (35.0) | 105 (34.8) | |
Primary tumora) | ||||
Uncontrolled | 23 (23.5) | 39 (19.6) | 82 (27.7) | 0.092 |
Controlled | 75 (76.5) | 160 (80.4) | 214 (72.3) | |
Extracranial metastasis | ||||
Absent | 26 (26.5) | 33 (16.5) | 41 (13.6) | 0.011 |
Present | 72 (73.5) | 167 (83.5) | 261 (86.4) | |
Symptoms | ||||
No | 14 (14.3) | 24 (12.0) | 34 (11.3) | 0.725 |
Yes | 84 (85.7) | 176 (88.0) | 268 (88.7) | |
No. of BMs | ||||
≤ 4 | 51 (52.0) | 116 (58.0) | 163 (54.0) | 0.548 |
> 4 | 47 (48.0) | 84 (42.0) | 139 (46.0) | |
Location of BM | ||||
Supra- or infra-tentorial | 51 (52.0) | 109 (54.5) | 134 (44.4) | 0.068 |
Both | 47 (48.0) | 91 (45.5) | 168 (55.6) | |
Breast-GPA | ||||
0–1.0 | 13 (13.3) | 20 (10.0) | 34 (11.3) | 0.903 |
1.5–2.0 | 27 (27.6) | 63 (31.5) | 84 (27.8) | |
2.5–3.0 | 47 (48.0) | 89 (44.5) | 139 (46.0) | |
3.5–4.0 | 11 (11.2) | 28 (14.0) | 45 (14.9) |
Values are presented median (IQR) or number (%). BC, breast cancer; BM, brain metastasis; Breast-GPA, breast cancer-specific graded prognostic assessment; ECOG, Eastern Cooperative Oncology Group; HER2, human epidermal growth factor receptor 2; HR, hormone receptor; IQR, interquartile range.
a) Available data only.
Characteristic | 2005–2008 (group I) | 2009–2011 (group II) | 2012–2014 (group III) | p-valuea) |
---|---|---|---|---|
WBRT alone | 64 (65.3) | 114 (57.0) | 160 (53.0) | 0.036 |
SRS or FSRT alone | 18 (18.4) | 41 (20.5) | 81 (26.8) | 0.045 |
Op alone | 3 (3.1) | 7 (3.5) | 12 (4.0) | 0.657 |
Op or SRS or FSRT → WBRT | 9 (9.2) | 27 (13.5) | 39 (12.9) | 0.454 |
WBRT → SRS | 1 (1.0) | 2 (1.0) | 1 (0.3) | 0.358 |
Other brain-directed treatment | 3 (3.1) | 9 (4.5) | 9 (3.0) | 0.733 |
Subsequent systemic therapy | 77 (78.6) | 158 (79.0) | 235 (77.8) | 0.810 |
Anti-HER2 therapyb) | 23 (50.0) | 54 (62.1) | 66 (52.4) | 0.846 |
Baseline characteristics according to the year of brain metastasis diagnosis
Characteristic | 2005–2008 (group I) | 2009–2011 (group II) | 2012–2014 (group III) | p-value |
---|---|---|---|---|
No. of patients | 98 | 200 | 302 | |
Age at primary BC (yr) | 45.1 (39.2–51.9) | 45.5 (37.8–52.8) | 48.1 (41.8–53.7) | 0.019 |
Age at BM (yr) | 49.0 (41.4–56.1) | 48.3 (39.8–56.2) | 51.2 (45.6–57.4) | 0.008 |
Interval of primary BC and BM (mo) | 30.6 (14.4–48.9) | 29.4 (16.5–56.4) | 34.2 (19.2–54.0) | 0.482 |
Tumor subtype | ||||
HR+/HER2− | 17 (17.3) | 54 (27.0) | 96 (31.8) | 0.082 |
HER2+ | 46 (46.9) | 87 (43.5) | 126 (41.7) | |
Triple-negative | 35 (35.7) | 59 (29.5) | 80 (26.5) | |
Initial BC stage | ||||
Stage I | 11 (11.2) | 17 (8.5) | 28 (9.3) | 0.092 |
Stage II | 39 (39.8) | 56 (28.0) | 99 (32.8) | |
Stage III | 35 (35.7) | 70 (35.0) | 94 (31.1) | |
Stage IV | 13 (13.3) | 57 (28.5) | 81 (26.8) | |
ECOG | ||||
0–1 | 69 (70.4) | 130 (65.0) | 197 (65.2) | 0.601 |
2–3 | 29 (29.6) | 70 (35.0) | 105 (34.8) | |
Primary tumor |
||||
Uncontrolled | 23 (23.5) | 39 (19.6) | 82 (27.7) | 0.092 |
Controlled | 75 (76.5) | 160 (80.4) | 214 (72.3) | |
Extracranial metastasis | ||||
Absent | 26 (26.5) | 33 (16.5) | 41 (13.6) | 0.011 |
Present | 72 (73.5) | 167 (83.5) | 261 (86.4) | |
Symptoms | ||||
No | 14 (14.3) | 24 (12.0) | 34 (11.3) | 0.725 |
Yes | 84 (85.7) | 176 (88.0) | 268 (88.7) | |
No. of BMs | ||||
≤ 4 | 51 (52.0) | 116 (58.0) | 163 (54.0) | 0.548 |
> 4 | 47 (48.0) | 84 (42.0) | 139 (46.0) | |
Location of BM | ||||
Supra- or infra-tentorial | 51 (52.0) | 109 (54.5) | 134 (44.4) | 0.068 |
Both | 47 (48.0) | 91 (45.5) | 168 (55.6) | |
Breast-GPA | ||||
0–1.0 | 13 (13.3) | 20 (10.0) | 34 (11.3) | 0.903 |
1.5–2.0 | 27 (27.6) | 63 (31.5) | 84 (27.8) | |
2.5–3.0 | 47 (48.0) | 89 (44.5) | 139 (46.0) | |
3.5–4.0 | 11 (11.2) | 28 (14.0) | 45 (14.9) |
Values are presented median (IQR) or number (%). BC, breast cancer; BM, brain metastasis; Breast-GPA, breast cancer-specific graded prognostic assessment; ECOG, Eastern Cooperative Oncology Group; HER2, human epidermal growth factor receptor 2; HR, hormone receptor; IQR, interquartile range.
a)Available data only.
Treatment distribution according to the year of brain metastasis
Characteristic | 2005–2008 (group I) | 2009–2011 (group II) | 2012–2014 (group III) | p-value |
---|---|---|---|---|
WBRT alone | 64 (65.3) | 114 (57.0) | 160 (53.0) | 0.036 |
SRS or FSRT alone | 18 (18.4) | 41 (20.5) | 81 (26.8) | 0.045 |
Op alone | 3 (3.1) | 7 (3.5) | 12 (4.0) | 0.657 |
Op or SRS or FSRT → WBRT | 9 (9.2) | 27 (13.5) | 39 (12.9) | 0.454 |
WBRT → SRS | 1 (1.0) | 2 (1.0) | 1 (0.3) | 0.358 |
Other brain-directed treatment | 3 (3.1) | 9 (4.5) | 9 (3.0) | 0.733 |
Subsequent systemic therapy | 77 (78.6) | 158 (79.0) | 235 (77.8) | 0.810 |
Anti-HER2 therapy |
23 (50.0) | 54 (62.1) | 66 (52.4) | 0.846 |
Values are presented as number (%). FSRT, fractionated stereotactic radiotherapy; HER2, human epidermal growth factor receptor 2; Op, operation; SRS, stereotactic radiosurgery; WBRT, whole-brain radiotherapy.
a)p-value for trend,
b)In HER2+ patients.
Values are presented median (IQR) or number (%). BC, breast cancer; BM, brain metastasis; Breast-GPA, breast cancer-specific graded prognostic assessment; ECOG, Eastern Cooperative Oncology Group; HER2, human epidermal growth factor receptor 2; HR, hormone receptor; IQR, interquartile range. Available data only.
Values are presented as number (%). FSRT, fractionated stereotactic radiotherapy; HER2, human epidermal growth factor receptor 2; Op, operation; SRS, stereotactic radiosurgery; WBRT, whole-brain radiotherapy. p-value for trend, In HER2+ patients.