title: Extended trastuzumab therapy improves the survival of HER2-positive breast cancer patients following surgery and radiotherapy for brain metastases.
abstract: Brain metastases usually present late during the course of breast cancer and are associated with an unfavorable prognosis. It was previously demonstrated that the status of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor type 2 (HER2) may be altered in the time window between the emergence of the primary breast tumor and the development of metastases. The aim of this study was to compare the expression of ER, PR and HER2 in pathology samples of primary breast cancer and brain metastases in order to evaluate whether previously administered therapy was able to modify this status and determine whether biomarker alterations affect prognosis after the development of brain metastases. Data were collected from 62 patients who were initially diagnosed with breast cancer that had metastasized to the brain. The ER, PR and HER2 status of the samples from the primary tumors and the brain metastases was determined. Differences in the immunohistochemical profiles of ER, PR or HER2 between the primary tumors and the brain metastases in 17 patients (29.3%) were identified. The patients with HER2-positive brain metastases who received trastuzumab had no leptomeningeal metastases and exhibited a longer survival time after brain metastases compared to the HER2-positive patients who did not receive trastuzumab and the patients with HER2-negative brain metastases (P=0.0005). Our results suggested that the patients treated with trastuzumab following surgery and radiotherapy for brain metastases exhibited a better prognosis. Thus, the HER2 status in brain metastases requires re-evaluation and extended trastuzumab therapy is recommended after brain metastases.
authors.affiliation: Department of Neurosurgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511;
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Okita
authors.affiliation: Departments of Neurosurgery and Neuro-Oncology, National Cancer Center, Tokyo 1040045;
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Narita
authors.affiliation: Department of Neurosurgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511;
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Departments of Neurosurgery and Neuro-Oncology, National Cancer Center, Tokyo 1040045;
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Arita
authors.affiliation: Breast and Medical Oncology, National Cancer Center, Tokyo 1040045;
authors.forename: Kan
authors.initials: K
authors.lastname: Yonemori
authors.affiliation: Breast Surgery, National Cancer Center, Tokyo 1040045;
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kinoshita
authors.affiliation: Breast and Medical Oncology, National Cancer Center, Tokyo 1040045;
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fujiwara
authors.affiliation: Pathology and Clinical Laboratories, National Cancer Center, Tokyo 1040045;
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tsuda
authors.affiliation: Departments of Breast and Endocrine Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Komoike
authors.affiliation: Department of Neurosurgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511;
authors.forename: Hidemitsu
authors.initials: H
authors.lastname: Nakagawa
authors.affiliation: Departments of Breast and Endocrine Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tamaki
authors.affiliation: Pathology and Cytology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511, Japan.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tomita
authors.affiliation: Departments of Neurosurgery and Neuro-Oncology, National Cancer Center, Tokyo 1040045;
authors.forename: Soichiro
authors.initials: S
authors.lastname: Shibui
authors.affiliation: Department of Neurosurgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 5378511;
authors.forename: Motohiko
authors.initials: M
authors.lastname: Maruno
keywords: HER2; blood-brain barrier; brain metastases; breast cancer; trastuzumab