After about two decades in the front ranks of academic cancer research, the Vermont Cancer Center began the new century with its reputation intact. But warning signs soon emerged, followed by a downward trajectory that culminated nearly four years ago. That's when officials in the University of Vermont College of Medicine, where the center is housed, decided not to reapply to the National Cancer Institute for designation as a "comprehensive" cancer center. They concluded they couldn't make a credible case for meeting the institute's rigorous requirements for clinical, laboratory and other research.