Reirradiation for progressive brain metastases

Brain metastases constitute one of the most common distant metastases of cancer and are increasingly being detected with better diagnostic tools. The standard of care for solitary brain metastases with the primary disease under control is surgery followed by radiotherapy. Radiotherapy is also the primary modality for the treatment of multiple brain metastases, and improves both the quality of life and survival of patient. Unfortunately, more than half of these treated patients eventually progress leading to a therapeutic dilemma. Another course of radiotherapy is a viable but underutilized option. Reirradiation resolves distressing symptoms and has shown to improve survival with minimal late neurotoxicity. Reirradiation has conventionally been done with whole brain radiotherapy, but now studies with stereotactic radiosurgery have also shown promising results. In this review, we focus on reirradiation as a treatment modality in such patients. We performed a literature search in MEDLINE (www.pubmed.org) with key words brain metastases, reirradiation, whole brain radiotherapy, stereotactic radiosurgery, interstial brachytherapy, and brain. The search was limited to the English literature and human subjects.