Nuclear medicine in therapy and diagnosis

From the IAEA Division of Human Health, Nuclear Medicine and Diagnostic Imaging Section

Proper nutrition

A gamma camera traces and detects radiopharmaceuticals inside a patient in order to produce diagnostic images.
(Photo: E. Estrada Lobato, IAEA)

Cancer affects everyone – regardless of age, gender, or walks of life – and represents a tremendous burden on patients, families and societies. Cancer is one of the leading causes of death in the world just behind cardiovascular diseases, particularly in developing countries.

Cancer occurs when cells in the body divide and grow uncontrollably. This may happen in any part of the body and can take many different forms. The various forms can behave very differently from one another and may grow at differing rates, and respond to treatments inconsistently. The disease can also spread to other parts of the body through the bloodstream or lymphatic system ̶ which is called metastasis ̶ but the original site of the cancerous cells determines the cancer type.

Nuclear medicine and diagnostic imaging can help diagnose cancer in its early stages and may help discriminate a tumour from a non-tumour, stage the patients after diagnosis of cancer has been established, and monitor the patient's treatment response. Such characterization is crucial at several stages of clinical management.

Chișinău, Moldova
(Photo: E. Estrada Lobato, IAEA)

Immediately after diagnosis, any patient with cancer must be correctly staged in order to gain a prognosis and select the most appropriate treatment(s) (surgery, chemo- or radiotherapy, or combined treatments). In this scenario, radionuclide imaging is useful to localize tumour lesions and is also important for assessing the effectiveness of therapy as well as, during follow-up, to distinguish whether abnormalities are caused by nonspecific post-treatment changes, or are due to tumour recurrence. In all these applications, the highest clinical benefit is achieved with hybrid image fusion analysis with PET/CT.

In addition to helping to find and characterize diseases in many types of cancer, nuclear medicine can be used in therapy as a unique way to kill cancer cells with minimal damage to surrounding tissue. One radioactive pharmaceutical called iodine-131 can be an integral component for the effective treatment of thyroid cancer. Other radioactive pharmaceuticals can be used to treat different cancers, including lymphoma, neuroblastoma and metastatic prostate cancer.

The IAEA plays a vital role in helping countries to establish or upgrade oncology and radiotherapy centres, and to build capacity in nuclear medicine and diagnostic imaging for diagnosis, and in some cases, treatment.

An example of the IAEA support provided to Member States to enhance their capabilities can be seen in Moldova. The IAEA has been supporting Moldova through two national projects, in which the Nuclear Medicine and Diagnostic Imaging Section and the Technical Cooperation Department helped strengthen the nuclear medicine practice to improve chronic disease diagnosis. This was done by implementing SPECT/ CT in clinical practice and preparing a feasibility study for establishing a PET centre, and more recently by updating the SPECT/CT system to a PET/SPECT/CT system. These actions contribute towards an earlier cancer diagnosis, decreased mortality rates caused by late stage diagnosis, improved evaluation of therapy selection as well as therapy monitoring, long term evaluation of patients and improved care of population.

As one of many initiatives to provide support to the scientific and medical community to further improve patient management, the IAEA initiated and sponsored a coordinated research project to help doctors effectively evaluate and treat patients with a form of non-Hodgkin's lymphoma, a very fast growing and aggressive type of cancer, using a nuclear diagnostic imaging technique (PET scan). This project involved the IAEA in cooperation with eight research centres from Brazil, Chile, Hungary, India, Italy, Philippines, South Korea, and Thailand, and researchers from France, Italy, Turkey and the United Kingdom. The results of the project have led to the largest database of these types of PET scan studies to date, as well as a series of recommendations on how doctors can evaluate the scans to effectively treat patients with this form of non-Hodgkin's lymphoma. The database will be a resource for further research in this area of medicine, and the recommendations are expected to influence how patient treatment is managed throughout entire treatment cycles, helping to ensure that patients receive safe and appropriate care. This study has received international recognition and was presented with the Editor's Choice Award as one of the best three papers published in 2014 in the Journal of Nuclear Medicine.

Robert Carr, one of the authors of the IAEA paper, receiving the Journal of Nuclear Medicine Editor's choice award among other recipients at the Society of Nuclear Medicine and Molecular Imaging annual meeting. (Photo: R. Kashyap, IAEA)