You have been asked to participate in this research study because you have an advanced cancer that produces a protein called carcinoembryonic antigen (CEA).  The purpose of this study is to determine the highest dose of a radioactive-labeled antibody called Y-90 anti-CEA M5A antibody that can be given without causing unmanageable side effects. Another purpose is to use a series of nuclear imaging studies to estimate the radiation dose of Y-90 anti-CEA M5A antibody to the whole body, normal organs and tumor.  Your treatment on this study is expected to last for 2-6 months, depending on whether you are not experiencing unmanageable side effects and whether your disease is not getting worse.  After your treatment on this study is over, your medical condition will be followed for approximately six months on this study, or until your cancer progresses (gets worse), or until you start another cancer treatment.