Patterns of care with regard to whole-brain radiotherapy technique and delivery among academic centers in the United States

Abstract

Despite the recent advances in systemic therapy, metastatic spread to the brain continues to be the most common neurologic complication of many cancers. The clinical incidence of brain metastases varies with primary cancer diagnosis, with estimates ranging from 1.2%-19.8%.1,2 Metastatic spread to the brain is even more prevalent at autopsy, with evidence of intracranial tumor being found in 26% of patients in some series.3 It is possible that the clinical incidence of metastatic disease to the brain will continue to increase as newer therapeutic agents improve survival and imaging techniques continue to improve. The management of brain metastases has changed rapidly as technological improvements have made treatment increasingly safe and efficacious. Traditionally, treatment consisted of radiotherapy to the whole brain, with or without surgical resection.4,5 More recently, stereotactic radiosurgery (SRS) has been adopted on the basis of evidence that it is safe and efficacious alone or in combination with radiotherapy to the whole brain.6 Further evidence is emerging that neurocognitive outcomes are improved when whole-brain radiotherapy (WBRT) is omitted, which possibly contributes to improved patient quality of life.7 Taking into account this and other data, the American Society for Radiation Oncology’s Choosing Wisely campaign now recommends not routinely adding WBRT to radiosurgery in patients with limited brain metastases.8 Despite this recommendation, many patients continue to benefit from WBRT, and it remains a common treatment in radiation oncology clinics across the US for several reasons. Many patients present with multiple brain metastases and are ineligible for radiosurgery. Even for technically eligible patients, WBRT has been shown to improve local control and decrease the rate of distant brain failure over radiosurgery alone.6 With higher rates of subsequent failures, patients receiving radiosurgery alone must adhere to more rigorous follow-up and imaging schedules, which can be difficult for many rural patients who have to travel long distances to centers.