Fighting cancer: history and role of nuclear medicine

In 1898, Pierre and Marie Curie isolated two new chemical elements: radium and polonium. In 1901, radium prepared by Pierre Curie was used for the first time to treat patients with skin lesions.

When war broke out in Europe in 1914, Marie Curie, who had already lost her husband, enlisted to help the wounded. While amputations were inevitably common in these emergency situations, the scientist worked on other solutions to help the wounded, employing x-rays to detect foreign objects in the body.

By the end of the war, the results spoke for themselves with over a million wounded helped thanks to Marie Curie's x-ray techniques. The United States then became interested in her work and funded the continuation of her research.

The production of radioisotopes subsequently developed in the United States after World War 2. One of these, technetium-99, became more widely available in hospitals in the 1970s with the use of molybdenum-99/technetium-99 generators.

Technetium-99 is still used in more than 80% of diagnostic procedures in nuclear medicine. Radioisotopes are key in enabling doctors to diagnose certain diseases, including cancer. 

The principle is to inject a radioactive substance (a tracer), which by emitting gamma radiation or positrons makes it possible to perform functional imaging. Resulting images are either scintigraphies (with gamma radiation emission) or positron emission tomographies (PET scans). 

Radioisotopes can also be used for therapeutic applications. Their radiation can in some cases destroy cancer cells using high energy. The most powerful of them, alpha emitters (which emit a helium nucleus when they decay) are used in alpha therapy.

Targeted Alpha Therapy (TAT) has a dual objective:

• Destroy cancer cells
• Limit damage to healthy cells

Targeted alpha therapy treatments make it possible to target diseased cells using vectors (particularly antibodies) to which a radioactive isotope is attached. The radioisotope’s radiation destroys the DNA of the targeted cancer cells.

Up to the present, the isotopes used for these treatments have mainly been beta (β) emitters. The specific nature of alpha emitters, whose energy is much higher and range much lower, could potentially improve the treatment of certain diseases while reducing side effects.

However, the supply of alpha-emitting radioisotopes is a constraining factor. The development of alpha therapy is dependent on it. Research into new methods for the production and purification of radioisotopes is ongoing and should be supported*.

The foundation of nuclear and medical expertise underpinning the creation of Orano Med in 2009 has enabled the emergence of lead-212 alpha therapy. Thanks to the group's long standing expertise, Orano Med's teams are now able to produce this isotope at the required purity level.

Production is carried out in several stages: the video below details the different stages.

The production processes are being industrialized. Orano Med is working with its partners to develop new lead-212 alpha therapies to treat various cancer types for which the therapeutic options are currently limited.

To learn more about recent advances in nuclear medicine and Orano Med's collaborations in this field, you can watch the video below.