Novel tracers and their development for the imaging of metastatic prostate cancer.

There are presently no accurate methods of imaging prostate cancer metastases to bone. An unprecedented number of novel imaging agents, based on the biology of the disease, are now available for testing. We reviewed contemporary molecular imaging modalities that have been tested in humans with metastatic prostate cancer, with consideration of the studies' adherence to current prostate cancer clinical trial designs. Articles from the years 2002 to 2008 on PET using (18)F-FDG, (11)C-choline, (18)F-choline, (18)F-flouride, (11)C-acetate, (11)C-methionine, and (18)F-fluoro-5alpha-dihydrotestosterone in patients with metastatic prostate cancer were reviewed. Although these studies are encouraging, most focus on the rising population with prostate-specific antigen, and many involve small numbers of patients and do not adhere to consensus criteria for clinical trial designs in prostate cancer. Hence, although many promising agents are available for testing, such studies would benefit from closer collaboration between those in the fields of medical oncology and nuclear medicine.