"Studies have consistently demonstrated that the risk of CNS involvement is high in patients with HER2-positive metastatic breast cancer. Incidence ranges from 15% to 55%, depending on length of follow-up and stringency of screening. Within the HER2-positive cohort, estrogen receptor (ER)-negative disease confers a greater risk than ER-positive disease. In a 3,000-plus patient cohort from a National Comprehensive Cancer Network database, women with ER-negative disease had a 63% increased risk over ER-positive patients, he said."
"compared to patients with triple-negative breast cancer, those with HER2-positive disease have a longer time from metastatic diagnosis to CNS relapse (approximately 1 year vs < 6 months), greater control of extracranial disease at the time of CNS relapse (50% vs rarely), and longer median overall survival from the time of CNS relapse (1–2 years vs 3–5 months). However, patients with triple-negative disease rarely die as a result of CNS progression alone, whereas up to 50% of those with HER2-positive disease do, he pointed out."
"Patients with HER2-positive disease who receive local therapy as the primary approach to CNS metastasis often develop progression over the ensuing months and years."
“Our treatment goals are to prolong survival, palliate neurologic symptoms, and prevent symptom progression. And we have to balance treatment-related toxicities with overall brain control and minimize the risk of ‘neurologic’ death—that is, death from the progression of the CNS metastases,” Dr. Winer said.
How to Approach the Problem of CNS Metastasis in HER2-Positive Patients
http://www.ascopost.com/issues/march...-patients.aspx