WeighiNg fuNctiONaL aNd prOgressiON adVaNtages

In a plenary session at ASCO 2015, Brown et al. presented the results of Alliance NCCTG N0574, a phase 3 trial comparing whole-brain radiation therapy (WBRT) plus radiosurgery (SRS) to SRS alone in patients with 1 to 3 brain metastases, each <3 cm, by contrast magnetic resonance imaging (MRI). The primary endpoint was cognitive progression (CP), defined as decline >1 standard deviation (SD) from baseline in any of the 6 cognitive tests conducted at 3 months. A total of 213 patients were enrolled, with 2 ineligible and 3 cancels prior to receiving treatment. Cognitive progression at 3 months was more frequent after SRS+WBRT vs SRS alone (88.0% vs 61.9% respectively, p=0.002). There was more deterioration in the SRS+WBRT arm in immediate recall (31% vs 8%, p=0.007), delayed recall (51% vs 20%, p=0.002), and verbal fluency (19% vs 2%, p=0.02). Intracranial tumour control at 6 and 12 months were 66.1% and 50.5%, respectively, with SRS alone vs 88.3% and 84.9%, respectively, with SRS+WBRT (p<0.001). Differences in median overall survival (OS) were statistically nonsignificant at 10.7 months for SRS alone vs 7.5 months for SRS+WBRT respectively (HR=1.02, p=0.93).