Trastuzumab treatment beyond brain progression in HER2-positive metastatic breast cancer.
BACKGROUND
Although trastuzumab therapy improves survival in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer, 40% of patients develop brain metastasis (BM) even when extracranial disease is under control. We studied whether trastuzumab therapy beyond or after BM was beneficial to patients with BM.


METHODS
The effect of trastuzumab on survival after BM was analyzed in 78 HER2-positive breast cancer patients. Patients were grouped according to trastuzumab therapy; no treatment and treatment before and after BM were diagnosed.


RESULTS
Overall survival after the diagnosis of BM as well as time to progression (TTP) of intracranial tumors was prolonged in patients who received trastuzumab after BM was diagnosed. Conversely, BM occurred much later in patients who received trastuzumab before BM. In the multivariate Cox regression model, age at BM <50 years, disease-free interval >or=24 months, TTP of intracranial tumor >or=4.8 months, and trastuzumab treatment after BM were significantly associated with longer survival after the onset of BM.


CONCLUSIONS
Trastuzumab therapy after the onset of BM in HER2-positive breast cancer patients is associated with a significant survival benefit after BM diagnosis compared with patients who never received or completed trastuzumab before the BM diagnosis.
Park
I H
IH
Center for Breast Cancer, National Cancer Center, Goyang, Gyeonggi, Korea.
Ro
J
J
Lee
K S
KS
Nam
B H
BH
Kwon
Y
Y
Shin
K H
KH
D000328:Adult; D000368:Aged; D000465:Algorithms; D000911:Antibodies, Monoclonal / Q000494:pharmacology / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality / Q000556:secondary*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D002277:Carcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D012189:Retrospective Studies; D016019:Survival Analysis; D000068878:Trastuzumab; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab