Renuka Iyer, MD, of the Department of Medicine, and Dan Iancu, MD, of the Department of Pathology and Laboratory Medicine at Roswell Park Cancer Institute (RPCI) are studying how a new test called CellSearch could be used with standard radiographic methods to monitor treatment results in patients with locally advanced or metastatic gallbladder or biliary duct cancers. The goal of the study is to see if CellSearch could predict patient response to therapy earlier than traditional measures. Patients could be spared the expense and unpleasant side effects of continuing with an ineffective treatment course.
CellSearch, (manufactured by Veridex, LLC), is the first automated, FDA-approved system for detecting and counting circulating tumor cells (CTCs) in the blood of patients with metastatic breast, prostate and colon cancers. It requires just 7.5 milliliters of blood—less than two teaspoons—and is sensitive enough to detect a single CTC in that small sample. Used in conjunction with imaging, the results can help guide treatment decisions.
"Seeing the tumors shrink doesn't tell the whole story," explains Dan Iancu, MD, of the Department of Pathology and Laboratory Medicine. "Even if you shrink the tumor, you could still have CTCs or cancer stem cells that are not destroyed." If CTC levels remain high after chemotherapy has ended, chances are that the prognosis is poor and the cancer may recur. In the long run it might be possible to unite genetic, serologic, and pathologic biomarkers to see how patients are likely to respond before treatment begins.
CellSearch can support research as well, enabling scientists to capture CTCs to study their genetic makeup in the search for new, targeted therapies. The technology was cited at this year's Cleveland Clinic Medical Innovation Summit as one of the Top 10 Medical Innovations for 2009, and was awarded the 2009 Prix Galien—the equivalent of the Nobel Prize in pharmaceutical research and development.