Although use of the term "theranostic" is relatively recent, the concept goes back to the earliest days of nuclear medicine, with the use of radioiodine for diagnosis and therapy of benign and malignant thyroid disease being arguably the most successful molecular radiotherapy in history. A diagnostic scan with123I-,124I-, or a low activity of131I-iodide is followed by therapy with high activity131I-iodide. Similarly, adrenergic tumours such as phaeochromocytoma and neuroblastoma can be imaged with123I-metaiodobenzylguanidine (MIBG) and treated with131I-MIBG. Bone scintigraphy can be used to select patients with painful bone metastases from prostate cancer who may benefit from treatment with beta- or alpha-particle emitting bone seeking agents, the most recent and successful of which is223Ra radium chloride. Anti-CD20 monoclonal antibodies can be used to image and treat non-Hodgkins lymphoma, though this has not been as commercially successful as initially predicted. More recently established theranostics include somatostatin receptor targeting peptides for diagnosis and treatment of neuroendocrine tumours with agents such as68Ga-DOTATATE and177Lu-DOTATATE, respectively. Finally, agents which target prostate specific membrane antigen (PSMA) are becoming increasingly widely available despite the current lack of a commercial product. With the recent licensing of the somatostatin peptides and the rapid adoption of68Ga- and177Lu-labelled PSMA targeting agents, we have built upon the experience of radioiodine and are already seeing a great expansion in the availability of widely accepted theranostic radiopharmaceuticals.
The British journal of radiology. 2018 Feb 23 [Epub ahead of print]
James R Ballinger
Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, London, UK.