Brain metastases from gastrointestinal tumours: tailoring the approach to maximize the outcome

Brain metastases from the gastrointestinal cancers (GI) are uncommon, but their incidence is constantly increasing due to several reasons, including improved systemic therapy and survival. Nevertheless, the average outcome of these patients is poor and related to patients' or disease characteristics, and to the availability of treatment options. Because of the lack of evidence-based recommendations, no optimal treatment strategy has been defined. The approach to brain metastases remains often tailored, and the action plan is selected on the basis of their number, size and location, the presence of symptoms and the extra-cranial disease status. Clinical prognostic factors have been identified and grouped into index scores that can be helpful in the treatment decision making. At the same time, molecular factors contributing to brain metastases are being revealed, and the role of the unique brain microenvironment is beginning to be investigated. The aim of this review is to present and discuss available data on brain metastases from GI cancers.