Evolution of the techniques of radiation therapy in the management of lymphoma.

Radiation techniques for the treatment of Hodgkin's disease have evolved dramatically in the past century. Shortly after the discovery of X-rays, the lymphomas in general, and Hodgkin's disease in particular, were noted to be radiosensitive. However, equipment limitations restricted the ability to administer sufficient doses to adequate depth to ensure long-term control. This situation improved sequentially with the development of the Coolidge tube, (60)Co machine, and medical linear accelerators. With megavoltage radiation it was possible to demonstrate cures of stage I-II disease with high-dose extended-field irradiation. When combined modality therapy programs were introduced, this permitted restriction of radiation fields and doses in order to decrease toxicity. Innovative advanced technologies such as PET simulation, 3-D treatment planning, intensity-modulated radiotherapy, active breathing control, and proton therapy have further improved the outcomes for patients treated with irradiation.