Primary and metastatic brain tumors.

Abstract

High-grade malignant gliomas (HGG) are the most common and malignant primary central nervous system tumors. Despite therapeutic efforts and advances in biologic knowledge, these diseases remain lethal. Standard treatment of HGG is based on surgery and radiotherapy, usually followed by adjuvant chemotherapy. Many randomized trials addressing the role of post-radiation or "adjuvant" chemotherapy have been conducted in the last three decades, yielding inconclusive results. However, a statistically significant survival benefit with adjuvant chemotherapy has been demonstrated in two meta-analyses with nitrosourea-based adjuvant chemotherapy and a recent phase III trial has demonstrated a survival advantage for radiotherapy with concomitant and adjuvant temozolomide (TMZ) in patients with newly diagnosed glioblastoma. Since high-grade malignant gliomas can seldom be cured, the primary aim of treatments for recurrent disease is to improve progression-free survival (PFS), and to improve or preserve neurological functions. TMZ showed activity even in the treatment of recurrent HGG with a good toxicity profile, whether few data are available for effective treatments in patients treated with adjuvant TMZ. As a result, new agents and novel approaches are required. Furthermore, molecular studies to evaluate chemosensitivity predictors are necessary for patients' selection. Brain metastases are estimated to occur in 20% to 40% of cancer patients, with a higher risk in lung cancer, breast cancer and melanoma. The incidence of brain metastases is rising as results of better imaging procedures and improvements in treatments which leave more cancer patients at risk as survival increases. The prognosis is dependent on a number of factors such as histology of primary tumor, performance status, localization number and size of brain metastases and status of extra cranial disease. Surgery and radiotherapy are indicated in controlled disease with isolated brain metastases. Systemic chemotherapy represents he optimal treatment in chemosensitive tumors with multiple or isolated brain metastases.