Five studies reported on various combinations of treatments in patients with central nervous system (CNS) metastases from breast cancer.105-109
Two non-comparative phase II trials investigated the combination of radiotherapy and chemotherapy.105,106 Objective response rates were 58% and 76%, and complete response rates were observed in 7.4% and 12% of patients with breast cancer primary tumours in the Addeo 2008 and Cassier 2008 trials respectively. In the two studies, median overall survival was 8.8 months and 6.5 months, and 1 year survival was 18.5% and 28% in the Addeo 2008 and Cassier 2008 trials respectively. Median progression free survival was 6 months and 5.2 months in the Addeo 2008 and Cassier 2008 trials respectively.
One retrospective study reported significantly longer survival for surgery and radiotherapy compared to radiotherapy alone (p=0.001) as well as longer survival in patients who receive systemic chemotherapy after radiotherapy (p=0.015).108 Treatment modality, KPS and administration of systemic chemotherapy were significant prognostic factors for overall survival on multivariate analysis.
One retrospective study that included 15% patients with breast cancer as the primary tumour reported that surgery and SRS was associated with longer survival compared with SRS alone (p=0.020) and that the survival of SRS alone patients was statistically superior to the survival of patients who received WBRT alone (p=<0.001).107
A third retrospective study that included 17% patients with breast cancer primary tumour found significant improvement in local control (p=0.002) with the addition of a boost to WBRT and surgery.109