|A Conversation with Dr. Gary Kelloff|
Dr. Gary Kelloff is special advisor to NCI's Cancer Imaging Program in the Division of Cancer Treatment and Diagnosis. He is providing scientific input for the FDG-PET Lung and Lymphoma Projects being sponsored by the Foundation for the National Institutes of Health's Biomarkers Consortium (See "Director's Update").
What are the FDG-PET Lung and Lymphoma Projects?
These projects emerged from discussions among NCI, FDA, and the Centers for Medicare and Medicaid Services under the auspices of the Oncology Biomarkers Qualification Initiative (OBQI) announced earlier this year. The three federal health agencies believe that FDG-PET can provide an early indication of therapeutic response that is well correlated with clinical outcomes for chemotherapy in common forms of lung cancer and lymphoma.
FDG (fluorodeoxyglucose) is a glucose analog with a radioactive tracer attached to it. Tumor cells, particularly those from especially aggressive tumors, will consume significantly larger amounts of it than normal surrounding tissue. The result is that FDG's presence can be detected by PET (positron emission tomography) imaging in tumors as small as 1 centimeter.
These FDG-PET clinical trials could have enormous effect on patient management by validating a tool that can identify response to treatment and help in developing new drugs.
What is the focus of the FDG-PET lung study?
The FDG-PET lung project is based on the American College of Radiology Imaging Network phase II study of FDG-PET/CT as a predictive marker of tumor response and patient outcome in non-small-cell lung cancer (NSCLC). Studies have shown that lung cancer tumors have very high rates of glucose utilization and can be imaged efficiently by FDG-PET. The availability of such a sensitive measurement could streamline clinical trials of new treatments for lung cancer and, hence, accelerate new drug approvals.
What is the focus of the FDG-PET lymphoma study?
The FDG-PET lymphoma study is based on the Cancer and Leukemia Group B phase III randomized FDG-PET assessment and comparison of R-CHOP - the standard chemotherapy for diffuse large B-cell lymphomas (DLBCL) - with dose-adjusted-EPOCH-R, a new regimen for DLBCL. FDG uptake has been a significant early predictor of residual or recurrent disease and disease progression, as well as progression-free and overall survival. So far, there are no standardized criteria for PET imaging or established procedures for transmission, storage, quality assurance, and analysis of PET images. This project is a first step in developing the standardized protocols and endpoints that will be needed to move forward.
Will results and data from the FDG-PET projects be made publicly available?
One of the goals of the Biomarkers Consortium is to make the research results and data publicly available as quickly as possible. We expect that the data generated from these projects will be made publicly available through NCI'S Web-based cancer Biomedical Informatics Grid™, which enables the access and sharing of clinical trial data.