Anniversary paper: nuclear medicine: fifty years and still counting.

The history, present status, and possible future of nuclear medicine are presented. Beginning with development of the rectilinear scanner and gamma camera, evolution to the present forms of hybrid technology such as single photon emission computed tomography/computed tomography (CT) and positron emission tomography/CT is described. Both imaging and therapy are considered and the recent improvements in dose estimation using hybrid technologies are discussed. Future developments listed include novel radiopharmaceuticals created using short chains of nucleic acids and varieties of nanostructures. Patient-specific radiotherapy is an eventual outcome of this work. Possible application to proving the targeting of potential chemotherapeutics is also indicated.