In vivo imaging of apoptosis.

Despite over a decade of intense investigation there is still no routine method for the clinical imaging of apoptosis in oncologic patients. There have been multiple tracers proposed but none as of yet has received FDA approval. Radiolabeled annexin V is one of the few radiotracers that has been widely used in Phase II trials and is still under development. In this review we will first detail the general mechanisms involved with apoptosis and other common forms of cell death. Next we will outline the latest in vivo imaging data in animal models and humans including that obtained with radiolabeled annexin V. It is hoped that improved understanding of the complex biochemical pathways involved with cell death will lead to at least several radiopharmaceuticals with the ability to image apoptosis as part of improving the care and treatment of patients suffering from cancer.