The carrier molecule coupled with alpha particle (Bi-213-DOTATOC) led to shrinkage of primary tumours as well as liver and bone metastases (bottom image)© EU, 2012
"Image of the year": alpha therapy results on digestive tumours
A picture is worth a thousand words. This is the reason why the image shown has been awarded the title of "image of the year" by the Society of Nuclear Medicine (SNM). It comes from a study led by the Joint Research Centre´s (JRC) Institute for Transuranium Elements (ITU) and conducted in collaboration with University Hospital Heidelberg
It illustrates the effectiveness of the use of a tumour specific carrier molecule (DOTATOC, able to recognise gastroenteropancreatic neuroendocrine tumours - GEP-NETs - cells) coupled with an alpha emitting particle (Bi-213) to treat multi-resistant GEP-NET tumours, showing the remarkable results that can be achieved.
According to the scientific committee awarding this prize at the 2012 SNM Annual Meeting (June 9-13): "it opens a new door for those patients whose cancer does not respond to traditional chemotherapy".
In this specific case, the study performed at clinical level proves that the use of the carrier molecule coupled with an alpha emitting particle (Bi-213-DOTATOC) provided efficient treatment of gastroenteropancreatic neuroendocrine tumours (GEP-NETs). These are rare, slow growing tumours that develop in the digestive system and are distributed throughout the body and which frequently develop resistance to common beta therapy. Patients tolerated the treatment well, and there was no acute kidney, endocrine or hematologic toxicity.
This Joint Research Centre (JRC) study was conducted in the framework of the Seventh Framework Programme of the European Atomic Energy Community (Euratom) for nuclear research and training activities.
Targeted Alpha Therapy (also called Alpha-Immunotherapy) is considered a new approach to cancer treatment. It is based on the coupling of alpha particle emitting radioisotopes to tumour selective carrier molecules, such as monoclonal antibodies or peptides. These molecules have the ability to selectively target tumour cells even if they are spread throughout the body.
Radionuclides that emit alpha particles seem particularly promising for targeted therapy, since alpha particles are highly energetic and have a very short range in human tissue, corresponding to only a few cell diameters, much less than the commonly used beta radioisotopes. Consequently, targeted alpha therapy allows the specific targeting and killing of individual malignant cells, while minimising the toxicity to surrounding healthy tissue.
The JRC-Institute for Transuranium Elements, located in Karlsruhe (Germany), is specialised in synthesis and in vitro testing of novel radio conjugates, as well as preclinical research and clinical trials with partner hospitals.