Brain metastases in Asian HER2-positive breast cancer patients: anti-HER2 treatments and their impact on survival.
BACKGROUND
In Asia, large-scale studies on anti-HER2 treatment in HER2-positive breast cancer patients with brain metastases are limited. We studied the treatment patterns of these patients in Asia to evaluate the impact of anti-HER2 treatment on the time to occurrence of brain metastases (TTBM) and survival after brain metastasis (BM).


METHODS
A retrospective study of HER2-positive breast cancer patients diagnosed with BM between January 2006 and December 2008 in six Asian countries was conducted. Demographics, tumour characteristics, treatment details, and events dates were collected from medical records.


RESULTS
Data from 280 patients were analysed. Before BM, 63% received anti-HER2 treatment. These patients had significantly longer TTBM than those without anti-HER2 treatment (median 33 vs 19 months; P<0.002). After BM, 93% received radiotherapy, 57% received chemotherapy, and 41% received anti-HER2 treatment (trastuzumab and/or lapatinib). Use of both anti-HER2 agents, primarily sequentially, after BM demonstrated the longest survival after BM and was associated with a significant survival benefit over no anti-HER2 treatment (median 26 vs 6 months; hazard ratio 0.37; 95% CI 0.19-0.72).


CONCLUSIONS
Anti-HER2 treatment before BM was associated with longer TTBM. Anti-HER2 treatment after BM was associated with a survival benefit, especially when both trastuzumab and lapatinib were utilised.
Department of Medical Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore.
Y S
YS
Yap
G H
GH
Cornelio
B C R
BC
Devi
C
C
Khorprasert
S B
SB
Kim
T Y
TY
Kim
S C
SC
Lee
Y H
YH
Park
J H
JH
Sohn
N
N
Sutandyo
D W Y
DW
Wong
M
M
Kobayashi
S H
SH
Landis
E M
EM
Yeoh
H
H
Moon
J
J
Ro
D000328:Adult; D000368:Aged; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology / Q000556:secondary*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D005260:Female; D006801:Humans; D000077341:Lapatinib; D008875:Middle Aged; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use*; D011799:Quinazolines / Q000627:therapeutic use; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D012189:Retrospective Studies; D000068878:Trastuzumab; D055815:Young Adult
D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000077341:Lapatinib; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab