Breast cancer subtypes and survival in patients with brain metastases

Abstract

Introduction Brain metastases (BM) occur in up to one third of patients with metastatic breast cancer (MBC), whose incidences and prognoses by breast cancer subtypes in BM have not been well delineated.

Risk factors for brain relapse in HER2-positive metastatic breast cancer patients

“…The risk factors for the development of brain relapse in general breast cancer patient populations include younger age, aggressive tumor growth, dissemination to other distant sites and steroid receptor negativity [18][19][20][21][22]. The knowledge of the risk factors for brain relapse in a subset of HER2-positive advanced breast cancer patients has been limited, and our study is among the few investigating this issue [23,24].…”

“…In this series the steroid receptor status and tumor grade were not related to the risk of brain relapse. The lack of steroid receptor expression is considered an adverse prognostic factor in general breast cancer population, and also includes increased risk of brain relapse [18][19][20][21][22]31]. The knowledge on the predictive value of steroid receptor status for brain metastases in HER2-positive advanced breast cancer patients is scarce.…”

“…It is hoped that determining tumor and host risk factors for brain metastasis might allow selection of candidates for preventive strategies. Most studies addressing risk factors for brain relapse included unselected breast cancer patients [18][19][20][21][22], whereas little is known on this issue in HER2-positive breast cancer patients [23,24]. In this study we assessed retrospectively the impact of selected clinical and pathological variables on the risk of brain relapse in a large, unselected group of patients with metastatic HER2-positive breast cancer.…”

Antidepressant use and risk of central nervous system metastasis

“…Triple-negative tumor status (ER-/PR-/HER2-), ER-, PR-, and basal-like tumors also were associated with an increased risk of brain metastasis [153,175,187,193,195,216,219,221,230]. Brain metastasis as the first site of metastasis developed quickly and most frequently in breast cancer patients with HER2 and triple-negative tumors [153,231].…”

“…Overexpression of HER2 is repeatedly supported as a risk factor for brain metastasis in breast cancer patients [57,175,193,221,222], and the risk has increased since the development of trastuzumab (Herceptin; Genentech, San Francisco, CA), a monoclonal antibody therapy [57]. Trastuzumab has significantly reduced progressive systemic disease in HER2 positive patients, but the likelihood of developing brain metastasis is higher [223].…”