Clinical and Molecular Correlates of Positron Emission Tomography (PET) With 89Zr-DFO-huJ591 in Metastatic Prostate Cancer

The purpose of this study is to define the safety and accuracy of 89Zr-DFO-huJ591 PET scans. By improving our ability to find cancer cells, the investigators hope to be able to improve treatment for patients in the future. The study doctors want to determine whether a new kind of scan, called a 89Zr-DFO-huJ591 PET scan, can specifically see prostate cancer that has spread to other parts of the body, especially the bones. The study doctors will also look at how the 89Zr-DFO-huJ591 reacts with the body and how long it stays in the body. The investigators will also ask the patient to have a biopsy performed. The study doctors will compare the findings the investigators see on the scans with findings on the optional tissue biopsy. Finally, the investigators will compare the pictures from a 89Zr-DFO-huJ591 PET scan with those of a standard PET scan (called FDG PET) and standard CT scans or magnetic resonance (MRI) scans or bone scans, depending on which standard scans the doctor has ordered. PET scanning uses a small amount of radiation attached to a molecule that is taken up by the cancer. In this trial, the patient will undergo two types of PET scans. One uses FDG. FDG is a standard tracer for PET scans. The patient will also undergo another type of PET scan that is experimental. This experimental PET uses a radioactive protein called J591. The radiation source is a type of metal called zirconium-89 (89Zr). The whole tracer, J591 plus the 89Zr, is abbreviated as 89Zr-DFO-huJ591. This tracer is what is being studied. The tracer used in a scan should find where the cancer is in the body.