New guidelines on radiation therapy aim to help physicians more effectively treat pediatric Hodgkin lymphoma (HL) while reducing the radiation dose to normal tissue.
Previous guidelines for pediatric HL have focused on 2D imaging and bony landmarks to define dose volumes for radiation therapy, and they’ve recommended treating large volumes of normal tissue, in part, because of uncertainty about which lymph node areas were involved.
The new guidelines, published in Practical Radiation Oncology, describe how to use modern imaging and advances in radiation therapy planning technology to treat patients with pediatric HL while decreasing the risk of late side effects, including second cancers and heart disease.
The authors describe methods for identifying target volumes for radiation therapy and how to implement the concept of involved-site radiation to define radiation target volumes and limit the dose to normal organs at risk.
According to the guidelines, accurate assessment of the extent and location of disease requires both contrast-enhanced CT as well as FDG-PET.
The document describes how the evaluation of response to chemotherapy influences the targeting of the lymphoma and the volume of normal tissue treated, by fusing CT and FDG-PET images taken before and after chemotherapy to CT imaging taken for radiation therapy planning.
“The emergence of new imaging technologies, more accurate ways of delivering radiation therapy, and more detailed patient selection criteria have made a significant change in our ability to customize treatment for many cancer patients,” said lead guideline author David C. Hodgson, MD, of the University of Toronto in Ontario, Canada.
“This guideline has the potential to reduce the radiation therapy breast dose by about 80% and the heart dose by about 65% for an adolescent girl with Hodgkin lymphoma. This shift in more personalized treatment planning tailored to the individual patient’s disease will optimize risk-benefit considerations for our patients and reduce the likelihood that they will suffer late effects from radiation therapy.”
