Prognostic factors in patients with brain metastases

Management of patients with brain metastases (BrM) has been evolving over time, with a general tendency towards a more aggressive treatment approach. Although whole brain radiotherapy (WBRT) remains the mainstay of treatment for the majority of patients, the indications for stereotactic radiosurgery (SRS) with or without WBRT have been expanding rapidly. In order to select patients who would benefit from the improved intracranial control rates obtained with advanced radiation therapy techniques, knowledge of prognostic factors is essential. Literature findings indicate that performance status, age and systemic tumour activity (extracranial metastases and primary tumour status) are the major determinants of survival for patients with BrM. Based on recursive partitioning analysis (RPA) of these factors, the Radiation Therapy Oncology Group has developed a prognostic classification system for patients with BrM. RPA Class 1 represents the most favourable subset of patients with Karnofsky performance status of > or = 70, age under 65 years, controlled primary tumour and no extracranial metastases. RPA Class 3 patients have KPS < 70, associated with poor median survival rates. RPA Class 2 contains the remainder of patients, a rather heterogeneous subset of patients with intermediate survival rates. This RPA classification system, which has been validated for patients treated with WBRT, surgery and SRS, respectively, appears to be a valuable tool for assessment of prognosis in patients with BrM.