Prognostic scores for brain metastasis patients: use in clinical practice and trial design

Brain metastases (BM) are the most serious neurological complication of cancer that results in significant morbidity and mortality in these patients. The most common primary malignancies that lead to BM include lung, breast and melanoma. Until recently the outcomes of patients with BM has been dismal. The current therapeutic options include surgery, whole brain radiation therapy (WBRT), stereotactic radiation (SRS), systemic therapy and symptom management only. Prognostic scores, a useful tool for BM patients, as an estimation of a patient's prognosis can guide tailored treatment for these patients. It is appropriate to recommend more aggressive approaches in patients with good performance status and limited disease and focus on symptom control and palliative measures when the disease is more advanced, or comorbidity preclude aggressive therapy. Due to vastly different outcomes, prognostic scores are important to stratify patients in clinical trials. A number of prognostic scoring systems for BM patients have been proposed that include Recursive Partitioning Analysis (RPA), the Score Index For Radiosurgery (SIR), the Basic Score for Brain Metastases (BSBM), the Rotterdam system (ROTTERDAM), the Golden Grading System (GGS), 2 Rades classification (RADES), the Graded Prognostic Assessment (GPA) and the disease specific Graded Prognostic Assessment (ds-GPA). In this article, we will review the important prognostic scoring systems and their utility in clinical decision making and trial design.