The International Lymphoma Radiation Oncology Group recently announced their new guidelines highlighting the use of 3-D computed tomography (CT)-based radiation therapy planning and the use of volumetric image guidance for an improved treatment of children with Hodgkin lymphoma.
These new approaches intend to decrease the dose of radiation to preserved tissue, diminishing the risk of late events. The publication will be available within the next weeks in the American Society for Radiation Oncology journal Practical Radiation Oncology.
Patients with pediatric Hodgkin lymphoma have been subject to similar radiation and chemotherapy regimens as the ones given to adults suffering from the condition, increasing the exposure of children to high dose therapies.
Previous guidelines for radiation therapy have emphasized the use of 2-D imaging and bony markers in order to characterize appropriate dosing of radiation therapy treating great volumes of normal lymphoma tissue due to the ambiguity concerning which areas had lymph nodes.
The guideline, entitled “Implementation of contemporary radiation therapy planning concepts for pediatric Hodgkin Lymphoma: Guidelines from the International Lymphoma Radiation Oncology Group,” underlines the use of new imaging methods and progress in radiation therapy planning equipment as effective approaches to treat pediatric Hodgkin lymphoma patients, lowering the risk for side events, such as heart disease and second cancers.
In the new guidelines, experts describe new approaches to identify the target volumes to be exposed to radiation therapy, and recommend how clinicians should implement the “involved site radiation therapy” concept in order to specifically delineate target radiation sections, limiting the dose to organs at risk.
In the guideline, the authors state that for an effective evaluation of the magnitude and place of the lymphoma, clinicians should evaluate the results provided by contrast-enhanced CT and fluorodeoxyglucose-PET (FDG-PET). The authors also describe the assessment of chemotherapy response on the target lymphoma and the volume of tissue preserved, by using a new established capacity to fuse CT and FDG-PET images captured before and after chemotherapy to CT imaging acquired 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 David C. Hodgson, MD, associate professor in the Department of Radiation Oncology at the University of Toronto in Toronto, a radiation oncologist at Princess Margaret Hospital/University Health Network in Toronto and lead author of the guidelines.
“This guideline has the potential to reduce the radiation therapy breast dose by about 80 percent and the heart dose by about 65 percent 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. We are also excited that these guidelines will be utilized in an upcoming Children’s Oncology Group Study of involved-site radiation therapy for high-risk Hodgkin lymphoma patients and eagerly await the study’s results,” he concluded.