Gene profiling predicted responses to colorectal, pancreatic cancer treatment

These two studies "highlight the direction that the field of oncology is going, both in terms of research and practice. The notion being that tumors that look the same under the microscope – colon cancers, for example – at the level of their molecular makeup may actually fit into several different categories that all look the same to a pathologist. We’re starting to use these categorizations based on the genetic makeup, the profile, and of what genes are turned on and off to help us make treatment decisions about which drugs might work best against which particular tumors, and which drugs might not work at all," Dr. Neal J. Meropol said.

The studies look at different ways of profiling tumors and tumor cells that ultimately could help guide treatment by predicting which tumors will respond to chemotherapy and which are likely to develop resistance.

Dr. Yu’s study of pharmacogenetic modeling "shows that it’s possible using a noninvasive methodology – simply a blood sample – to identify tumor cells and to characterize them at the molecular level. This is important, first of all, because it doesn’t require another biopsy of a patient’s tumor, which would be more invasive," Dr. Meropol said. "But, also, we know that when a tumor that initially responds to treatment starts to grow again, it has acquired new mutations, new characteristics that make it resistant to the therapy that it once responded to. This new technique allows you to sample the tumor over time through the bloodstream and change therapy appropriately based on changes in the tumor genomics at that point in time."

Dr. Neal J. Meropol is chief of hematology and oncology at Case Western Reserve University, Cleveland. He gave these comments as moderator of the press briefing. He has been a consultant or advisor to Precision Therapeutics.