'Dose painting': Customizing radiation treatment
By using biological data gleaned from PET imaging, researchers move closer to treating cancer with very targeted, high doses of radiation tailor-made for every single tumor.
A molecular-imaging technique using positron emission tomography (PET) sheds enough light on the biological processes of tumors that researchers hope to one day treat cancers with very targeted, high doses of radiation therapy customized for each individual tumor, according to research presented last week.
The study was presented at the Society of Nuclear Medicine's 57th Annual Meeting in Salt Lake City, Utah. Researchers used PET, X-ray computed tomography, and Philips-developed pharmacokinetic-modeling software to determine a tumor's anatomy and physiology and develop a high-dose intensity modulated radiation therapy (IMRT) plan tailored for that particular tumor. Customizing radiation in this way is called "dose painting."
"The research that we are conducting...[is] moving closer to more personalized treatment of hard-to-treat cancers based on the biology of each individual patient's tumor," says Kristi Hendrickson, lead author of the study and medical physicist at the University of Washington Medical Center in Seattle. "By modeling the data acquired from PET scans, we can potentially reduce damage to surrounding healthy tissue, as well as provide the ability to do 'dose painting,' delivering a highly customized form of radiation therapy for each patient."
This study is just the latest to come out of several years of research. But because it involved only one patient--with advanced head and neck cancer who was scanned using PET as well as two imaging agents, 18F-FDG to measure glucose metabolism and 18F-FMISO to measure hypoxia--researchers say additional clinical trials are needed to better evaluate how effective IMRT treatment plans can be.