The Radiation Therapy Oncology Group (RTOG) and the American College of Radiology Imaging Network (ACRIN) have launched a collaborative trial to evaluate adaptive radiotherapy (RT) with FDG-PET/CT for patients with non-small cell lung cancer (NSCLC).
The trial—RTOG 1106 and ACRIN 6697—has the primary treatment objective of determining whether tumor dose can be escalated to improve the freedom from local-regional progression rate at two years using FDG-PET/CT scans to individualize adaptive RT plans.
"For the past several decades, RT for NSCLC has been a ‘one-size-fits-all’ regimen with patients receiving a uniform dose for six to eight weeks and with no change in treatment plans or fields, regardless of patient size, tumor size or location of the tumor," principal investigator Feng-Ming Kong, MD, PhD, of the University of Michigan, Ann Arbor, said in a statement.
Patients will be randomized into two groups, with the control arm receiving a uniform RT dose of 60 Gy. Participants in the experimental arm will have RT planning modified to provide the highest possible dose to the residual active tumor while keeping doses to normal lung tissue constant at 20 Gy and doses to other adjacent organs within safe limits. All participants will undergo FDG-PET/CT scans at baseline and after four weeks of treatment. Both arms will receive RT once a day, five days a week for six weeks.
"We will also individualize treatment to every patient’s cancer including the primary lung tumor and any involved lymph nodes,” said Kong. “We hope to achieve a 20 percent increase in local tumor control as well as an improvement in survival."
The trial will address the effectiveness of imaging to predict where disease is present and where more aggressive efforts at local control of the tumor need to be focused.
In a subset of participants, [F-18] fluoromisonidazole-PET/CT will be conducted at baseline to identify the presence of hypoxia, which inhibits the production of the oxygen-free radicals that enable radiation to damage DNA and kill tumor cells.