Theranostics with Ga-68 somatostatin receptor PET/CT: monitoring response to peptide receptor radionuclide therapy.

Peptide receptor radionuclide therapy involves selective targeting of neuroendocrine tumors through the somatostatin receptors, the aim being to increase radiation dose to the tumors and spare the normal tissue. The advantage of this internal radiation therapy is the ability to selectively target multiple metastases throughout the body. Early and accurate assessment of therapy response helps not only to identify the poor responders but also to personalize the treatment regimes with the aim of achieving maximum treatment benefit. This is the basis of theranostics.