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The promise of nuclear medecine

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Specialised institutes, laboratories, cyclotrons, training courses, innovative SMEs... In the space of a few years, Nantes has put in place a veritable network of expertise in the field of nuclear medicine. A group which now finds itself at the top level, not only in France but in Europe.

Next July, the second International Workshop on Innovative Personalized Radioimmunotherapy, will be held in Nantes (see below). It is no coincidence that the event is being held here : the centre in Nantes grouped together at the Isotop-4-Life consortium, has a chain of expertise which is unique in France; it includes the Institut de Cancérologie de l'Ouest - Cancer research institute (ICO) and the CHU – teaching hospital, the Nantes Angers cancer research centre (CRCNA), the Subatech laboratory at the Ecole des Mines, the University and the CNRS (National centre for scientific research) as well as the Arronax cyclotron - all of them the latest additions to the competitiveness cluster : Atlanpole Biothérapies. Two labels have been awarded as part of 'Investments for the future' in recognition of its level of excellence : the labex IRON and the Equipex ArronaxPlus.

"Over a number of years, Nantes has built up a comprehensive arsenal in this science, on the initiative of Jean-François Chatal, one of the founders of the CRCNA, and longtime head of Nuclear medicine at Nantes CHU (teaching hospital) and ICO (Cancer research institute), and a pioneer of immunotherapy in France", says Françoise Kraeber-Bodéré, professor and present head of Nuclear medicine. She herself received a "Victoire de la médecine" award for her work in 2009.

In fact nuclear medicine is not a new discipline : it has been used for more than fifty years in the case of thyroid cancer treatment for example."But nuclear medicine is a fast-growing field and has been for the last ten years, continues Françoise Kraeber-Bodéré. We now have some very effective tools for imaging, as well as for diagnosis and treatment."

On the imaging side, the development of tomography by the emission of positrons (PET), from the year 2000 onwards, was a major step forward in cancer research. By injecting a small amount of radioactive chemicals into the body, it is now possible to measure the metabolic activity of an organ, by monitoring the changes shown in the concentration of the radioactive 'tracers'. "This enables us to detect changes in tumors, and analyse the processes taking place, the doctor explained. Which in turn enables us to calculate the chances of survival, and recovery of the patient." The PET scan – of which there are now about a hundred in France – is often used in conjunction with a CT scan (x-ray computed tomogaphy), using 'multi-modal imaging' to get a complete picture. This makes it possible to detect and monitor smaIl tumors of around 5 mm. In addition, along with 18F which is generally used in conjunction with a radiolabelled glucose molecule (FDG), new radiotracers are being developed for diagnosis, and therapy follow-up.

 

Combining imaging and treatment

 

Meanwhile, on the treatment side, new and more effective radioactive drugs, are being developed. These products are safe for the patients to use, because their "half-life" is quite short – usually no more than a few hours. The medical personnel are closely monitored, and adverse side effects are rare. And of course there is no long-life nuclear waste. As a result these technologies are becoming more widely accepted.

According to Françoise Kraeber-Bodéré "Today the idea is to combine imaging and treatment. We can see how the drug is taken up into the diseased organ, and how fast, then treatment can be adapted to the patient, depending on what has been observed... This combintion promises to be very useful in the case of cancer treatment." Similarly, for the treatment of breast cancer, which is hormone-dependent, one method of treatment is to use hormone blocking therapy : a PET scan shows how the patient's body has reacted to the hormone blocking therapy, and the treatment can be adapted accordingly, offering alternative treatment where the therapy has been unsuccessful.

This approach is the culmination of a new trend in cancer research : the growth of personalised immunotherapy. Each patient is offered 'targeted' therapy which corresponds to their genetic and biological characteristics and also takes into account their environment and lifestyle. This kind of 'personalised' approach which leads to more effective treatment, and causes fewer side-effects, is rapidly being used more extensively.

Which diseases can be treated using these methods ? Most lymph node cancers, thoracic cancers, gastrointestinal cancers, leukemia, gynecologic cancers... but it is not only cancer which can benefit from nuclear medicine : it is also possible to treat inflammatory and cardiovascular diseases. Nuclear medicine could even play a role in neurology, using its images of the brain. Alzheimer's disease is another area where this technology can be used, enabling earlier detection of the condition (one of the key themes in the IRON project) and perhaps, in the near future, therapies.

 

New isotopes

 

Doctors now need more effective radio pharmaceuticals so that treatment therapies can be more effective : 18F attached to a glucose molecule, zirconium-89, yttrium-90, lutetium-177... This is where the physicists and chemists from the Arronax cyclotron – the most powerful in Europe, with an overall investment of 37 million euros - come in. "One of our activities is the production of new radioisotopes, for imaging as well as for therapy, Férid Haddad, deputy director of the cyclotron and lecturer at Nantes University, told us,. At the moment we are working on a total of seven  isotopes for medical use.." One of them, strontium-82, has even been sold to the United States, through a supplier in Nantes. Another isotope, copper-64, which shows up oxygen tension in tumors, and is an important parameter in the success of radiotherapy, is being investigated at  ICO and at the CHU.

For their part, the teams working at the Subatech lab (subatomic physics and associated technologies), specialists in particle physics centred on major research facilities such as the CERN, are using their knowlegde to design new imaging tools. One of the most important designs, in the Xemis (Xenon imaging system) project, is a "three photon camera", using a noble gas, called xenon. It provides accurate 'images' of tumor development, and helps to reduce the doses of medication. The camera also works with a new radio tracer – scandium, which is also being studied by the radiochemists at the lab. "We hope to be able to greatly enhance imaging, compared to techniques being used at the moment, explained Dominique Thers, assistant lecturer at the Ecole des Mines. This will provide patients with personalised treatment and more frequent scans. We are already changing the rules of the game." Subatech has just started building a prototype for use on small animals, with a budget of one million euros, as part of the ArronaxPlus Equipement d'excellence project, a world premier. A number of patents have been filed, and a major manufacturer is ready to take part in the venture. The objective being to do a feasibilty study for a three photon camera, for humans.

 

Economic spinoffs

 

The collaborative work of teams from different diciplines is one of the strengths of the center in Nantes. "It's important that we all manage to speak the same language", says Dominique Thers. Doctors, chemists, physicists, chemists and biologists all work in the field of nuclear medicine... There are even teams from human and social sciences. The research goes way beyond the goal of producing radionuclides and radiopharmaceuticals for therapeutic and diagnosistic purposes. There is also the question of how human and organisational factors are taken into account when dealing with medical advancement. Innovation constitutes a complex social process which is not  only concerned with the scientific side of things. Nuclear medicine should be seen in a socio-economic context, involving radioactivity, techniques, knowledge, and regulations. It addresses important issues at societal level, both for organisations and individuals. "For example it considers the question of patient perception of the risks involved in the new diagnostic examinations, and therapies explained Bénédicte Geffroy, head of the Social Sciences and Management department at the Ecole des Mines. What experience does she have of using ionising radiation in healthcare ? For healthcare professionals there is the question of the risks involved in handling low doses of radioactivity. What effect does this have on the way they work and to what degree ?"

A highly complex network has been built up, around the Nuclear Medicine department, (the NucSan project, funded by the regional council of the Pays de la Loire region, the IRON Laboratory of excellence). This network now offers a wide range of training courses for students. In particular there is a Master's course on tracer development and a degree course on radiation protection. Not forgetting the doctoral students and foreign teachers drawn here by the increasingly high profile of the center in Nantes.

Apart from they key issue of public health, there are important economic spin-offs resulting from all this. A number of collaborative projects have been set up, such as Theranean with  AAA  – Advanced Acceleration Applications.

Several startups have been founded, such as Chelatec, a spin-off from Inserm which was created ten years ago and specializes in radioisotopic labelling, or Atlab Pharma, which produces radiopharmaceuticals, ou AI4R. A large industrial group is also interested in these technologies. Overall, several hundred people are already working in this sector, be it in laboratories or in industry. This should launch the Nantes center for nuclear medicine into an upward spiral.

 

WIPR 2013: An international workshop in Nantes

 

The second Workshop on Innovative Personalized Radio-immunotherapy - WIPR, will be held in Nantes from July 9 to 12. Some 150 participants from all over the world will be coming to learn about the latest progress in radioimmunotherapy.

"We will be bring together all the actors involved in the chain : doctors, biologists, chemists, pharmacists, as well as involving the industrial sector, says Sandrine Huclier, associate professor at the University, and event organiser, who works on the chemistry of new radioisotopes such as scandium. What we want to do is provide the opportunity to exchange, either at round table discussions, or more informally, to discuss issues from the points of view academic researchers and industrial decision makers." There will be lots of topical issues under discussion : the production of new radioisotopes, their chemical composition, the use of antibodies or peptides, and the expected benefits of 'multi-modal' imaging ...

There will be an exhibition for the general public from 10 June at the Institut de Recherche en Santé de l'Université de Nantes (IRS-UN). The WIPR will be held at the new Pharmacy faculty of Nantes, and will take place over two weeks. This event will reinforce the position of the center in Nantes at the cutting edge of nuclear medicine both in France and internationally.

To know more : www.mines-nantes.fr/wipr201

 

For more information:

Nuclear medicine in healthcare : listen to the programme from 'Labo des savoirs'

Nuclear science and healthcare

Personalised treatment : www.inserm.fr and www.paristechreview.com

Issue 5 of the science magazine 'Têtes chercheuses'

Création site internet : Agence web Images Créations