Relationship Between Human Epidermal Growth Factor Receptor 2 (Her2) Status And Central Nervous System Metastases In Gastroesophageal Cancer.

145Background: Central nervous system (CNS) metastases (mets) in gastroesophageal (GE) cancers are rare. There have only been limited studies examining the role of HER2 status in CNS mets in GE cancers. Methods: A retrospective analysis was performed for patients (pts) treated for GE cancers at the Princess Margaret Cancer Centre from 2011-2016. Quantitative and qualitative data were collected for all pts with CNS mets. Kaplan-Meier method was used to calculate overall survival (OS) and CNS progression free survival (PFS) for CNS mets pts. Results: Of 34 GE cancer pts diagnosed with CNS mets, 11 were HER2+, 11 HER2- and 12 had unknown HER2 status. Median time from initial cancer diagnosis to CNS mets was 10.3 months (13.4 in HER2+, 5.8 in HER2-, 11.7 in HER2 unknown). Characteristics at CNS mets diagnosis included: median age 63; 85% male; 74% had extracranial systemic mets; performance status ECOG 0-1 (64%), 2 (12%), 3-4 (24%). Treatment for CNS mets is shown in Table 1. Median OS from diagnosis of CNS m...