Inoperable brain metastases from non-small cell lung cancer: what part does whole brain radiotherapy play in standard treatment?

Lung cancer is the second commonest cancer in the UK with an incidence in 2006 of 37 100, and is the commonest cause of death from cancer, causing more than 33 000 deaths (22% of cancer deaths) each year.1 More than three-quarters of lung cancers fall into the histological category of non-small cell lung cancer (NSCLC). Currently, 10% of patients with NSCLC present with symptomatic brain metastases, and between a quarter and a third of those who initially survive radical treatment for stage III NSCLC will go on to develop brain metastases during their remaining life span.2 It is anticipated that over the next decade, an increasing proportion will develop brain metastases as adjuvant chemotherapy, concurrent chemoradiotherapy for locally advanced disease and chemotherapy for metastatic disease result in longer overall survival times.

For several decades, administration of steroids followed by whole brain radiotherapy (WBRT) has been standard treatment for inoperable multiple brain metastases of any primary cancer. The duration of survival for patients with a diagnosis of multiple brain metastases is strongly influenced by their performance status and also by the presence or absence of active extracranial disease. Data from three North American clinical trials which studied dose and fractionation for WBRT were used to divide patients with brain metastases from a variety of primary sites into three prognostic subgroups using recursive partitioning analysis (RPA).3 The group identified as having the best survival were aged less than 65 years, had a Karnofsky Performance Status score ≥70 and had controlled primary disease with no metastases outside the brain. In this group, termed RPA class I, median survival was …