Fig. 1From: Prognostic factors of brain metastasis and survival among HER2-positive metastatic breast cancer patients: a systematic literature reviewPRISMA Diagram. aThis includes one additional article identified from the review of the bibliography of a systematic review/meta-analysis after initial record screening, hence there appears to be one extra article in this diagram; PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-AnalysesBack to article page