Palliative radiotherapy: history, recent advances, and future directions.

Radiotherapy has been used to palliate cancer symptoms since shortly after the time that X rays were discovered late in the 1800's. The 20th century witnessed improvements in treatment planning and delivery that permitted radiotherapy to serve as a successful, timely, and cost-efficient palliative intervention. Palliative radiation oncology has risen to the level of its own subspecialty, as evidenced by the formation of palliative radiation oncology clinical services and dedicated palliative radiotherapy guidelines, while additional changes have begun to alter the very definition and goals of palliative radiotherapy. Local treatment may now be offered with dual goals of symptom relief and the potential for increased disease-free or overall survival. While these new directions show great promise, novel strategies must be formulated to manage the increased complexity, workload, and cost of these approaches.