James L. Mulshine, M.D., professor at the Rush University Medical Center in Chicago, will be describing his use of quantitative imaging as a biomarker of drug response in lung cancer.
Lung cancer is still the world’s leading cause of cancer death; however, drug development is slow and expensive. The primary barrier is the outdated and imprecise method of evaluating drug response. Dr. Mulshine advocates using 3-D tumor imaging as a “surrogate endpoint” of measuring drug responsiveness rather than the unidimensional measurements currently used, much the way cholesterol levels rather than the frequency of heart attacks are now used to evaluate the efficacy of lipid-lowering drugs.
Spiral, or helical, CT scanning is a quick way to measure changes in tumor volume with high resolution. It can, therefore, be applied to “window-of-opportunity” drug trials, in which tumors are imaged both before and after drug exposure. Changes in tumor volume and signaling pathways precipitated by the drug treatment can be measured.
Tumor reduction assessed by high-resolution CT was recently used successfully as an endpoint in a Phase II trial of pazopanib, an oral angiogenesis inhibitor targeting VEGFR, PDGFR, and c-kit in patients with stage I–II non-small-cell lung cancer.