Brain metastases

Abstract

Metastatic tumors to the brain are an increasing cause of morbidity and mortality in patients with systemic cancers. Many
new therapies used to treat systemic cancers do not penetrate the central nervous system (CNS) and do not protect patients
from the development of brain metastases. Surgery, radiosurgery, and radiation therapy are all used to treat brain metastases.
It is in our opinion a mistake to use only one or two of these modalities to the exclusion of other(s). The role of systemic
chemotherapy is still limited, due to both the issues of drug delivery caused by the blood brain barrier and to the relative
resistance of many of these tumors to chemotherapy. Traditionally, brain metastases have been grouped together regardless
of the origin of the tumor and have been treated with a single algorithm. As we encounter more patients for whom treatment
of the brain metastases is an important determinant of survival, we must tailor our treatment strategies to individual tumor
types. Also, we must recognize differences in each tumor’s sensitivity to chemotherapy and radiotherapy and differences in
their biology.