Radioligand theranostics (RT) in oncology use cancer-type specific biomarkers and molecular imaging (MI), including positron emission tomography (PET), single-photon emission computed tomography (SPECT) and planar scintigraphy, for patient diagnosis, therapy, and personalized management. While the definition of theranostics was initially restricted to a single compound allowing visualization and therapy simultaneously, the concept has been widened with the development of theranostic pairs and the combination of nuclear medicine with different types of cancer therapies. Here, we review the clinical applications of different theranostic radiopharmaceuticals in managing different tumor types (differentiated thyroid, neuroendocrine prostate, and breast cancer) that support the combination of innovative oncological therapies such as gene and cell-based therapies with RT.

The balance between proliferation and programmed cell death – apoptosis – is essential for multicellular organisms which use apoptosis to regulate and maintain the number and type of their cells during embryogenesis, growth and homeostasis. Increased cell proliferation or enhanced cell loss can be caused by dysregulated apoptosis and are observed in various diseases: in clinical scenarios such as neurodegenerative disorders, myocardial infarction and stroke the rate of apoptosis is upregulated compared to the physiological situation, while in clinical scenarios such as cancer or autoimmune diseases which are connected with pathological proliferation, apoptosis is often downregulated. Therefore, non-invasive imaging of apoptosis is of great clinical interest as patients would clearly benefit from the diagnosis of cell loss post infarction or from monitoring apoptosis triggered by chemotherapy or radiation therapy of tumours. Several biochemical transformations occur in apoptotic cells offering different biological targets for the development of specific molecular biomarkers of apoptosis. Key steps that occur during apoptosis have already been evaluated; among these are the externalisation of phospholipid phosphatidylserine to the outer leaflet of the cell membrane, which can be visualized by labeled annexin A5 and the activation of caspases, especially effector caspase-3, which can be addressed by labeled enzyme substrates or synthetic caspase inhibitors. Here, recent advances in tracer development for the molecular imaging techniques PET, SPECT and optical imaging are presented, the discussion of breakthroughs is involved, drawbacks and methodological issues of apoptosis imaging are highlighted.

We describe the development and first evaluation of a novel S100A9 specific molecular imaging probe (Cy5.5-CES271) for optical imaging of local inflammatory activity in vivo.