Treatment of brain metastases in favorable prognosis patients

INTRODUCTION

Metastases are the most common intracranial tumor in adults, accounting for more than one-half of all intracranial tumors. The primary approaches to the treatment of brain metastases include whole brain radiation therapy (WBRT), surgery, and stereotactic radiosurgery (SRS). Although WBRT was the mainstay of treatment beginning in the 1970s, occasional long-term survivors were seen following surgical resection in patients without extracranial disease [1-4].

Analysis of large series of patients with brain metastases has identified those factors that predict a favorable response to treatment and improved survival. The key prognostic determinants and the management of patients with a favorable prognosis will be reviewed here.

The etiology, clinical manifestations, and diagnosis of brain metastases and the treatment of patients with a poor prognosis are discussed elsewhere. (See "Overview of the clinical manifestations, diagnosis, and management of patients with brain metastases" and "Treatment of brain metastases in poor prognosis patients".)

FAVORABLE VERSUS POOR PROGNOSIS

The median survival of patients who receive supportive care and are treated only with corticosteroids is approximately one to two months. The use of WBRT in large series increased the average survival from three to six months, and larger gains were seen in carefully selected subsets [5-8].

The key parameters that determine survival after the diagnosis of brain metastases are performance status, the extent of extracranial disease, and age. The importance of these factors in determining outcome was illustrated by the use of recursive partitioning analysis (RPA) to analyze prognostic factors in 1200 patients from three Radiation Therapy Oncology Group (RTOG) brain metastases trials [9].