The number of patents that is increasing in the field of radiopharmacy from 2000 until 2013 are over 4500 patents that have been deposited nationaly and internationally. However, only few of these patents had reached the market and became true radiopharmaceuticals. This paradigm is changing and the development of nanomaterials may be one of these factors. The development of nano-drugs for cancer imaging and therapy is desired. Besides all the investment (over 50 billion dollars) around the world, the result is quite promising and reveals a great deal of application of nanotechnology. In this review, some aspects related to tumor environment and radiopharmaceuticals (DDS) are studied.