An Innovative Solution
The historical focus of TRIUMF’s research has been in accelerator-based subatomic physics and the related accelerator, detector, and isotope-production technology. Not only can critical isotopes used for medical imaging and treatment be produced with TRIUMF’s accelerators (called cyclotrons), but the techniques used by subatomic physicists to peer “inside” the atom can be used to image and trace these agents inside the body to study human health and disease in research known as nuclear medicine.
The core of the TRIUMF nuclear medicine program is positron-emission tomography (PET) imaging, a technique whereby tiny amounts of radioactive nuclei known as radioisotopes are combined with certain biomolecules and injected into the body. The biomolecules can be “traced” by imaging the decay products (two photons produced by the decay of the radioactive nucleus via the emission of a positron) outside the body. PET allows the concentration of positron-labeled compounds to be determined quantitatively in space and time within the living body. PET is more sensitive than any other human imaging method, such as MRI or CT, and has now become the “gold standard” for the detection of cancer.
Many diseases alter functional relationships within and between organ systems. Functional molecular imaging enables metabolic change to be visualized. The most sensitive approach for acquiring functional images is to use biologically active molecules that are labeled with radioisotopes. The development of positron-emission tomography in the 1970s and the use of a sugar molecule labeled with 18F enabled researchers to measure glucose metabolic rates in the living human brain for the first time. The dramatic advances in the detailed understanding of the molecular basis for many diseases offers the opportunity to design targeted functional imaging agents that will revolutionize the specificity/selectivity of disease diagnosis and aid in the direction of therapeutic interventions.
TRIUMF’s life sciences program is literally saving lives every day through its scientific projects. A critical diagnostic imaging drug (FDG) is sent to BC Cancer Agency (BCCA) each day to diagnose cancer, determine treatment regimes, and follow treatment efficacy. Several thousand British Columbians have been helped with this TRIUMF-BCCA program. In another program, over a hundred patients suffering from ocular melanoma have been successfully treated and cured by the proton irradiation facility at TRIUMF.
Other basic research projects include the development of PET radiopharmaceuticals that act as enzyme inactivators to follow the course of enzyme replacement therapy used in children’s diseases such as Gaucher’s disease. TRIUMF is also working on the development of radiometal-based radiopharmaceuticals for use as possible cancer imaging and therapy agents. With the acquisition of the microPET scanner by UBC, the PET group has broadened its research to include other diseases such as cancer and diabetes.
TRIUMF has provided considerable expertise and advice to other PET centres across Canada. TRIUMF’s PET chemistry group has provided both the Edmonton Cross Cancer PET facility and BCAA with 18F before the installation of their own cyclotrons.
The increased emphasis on PET has brought significant commercial interest in the development and production of enriched target material, automated chemistry devices, and other systems to carry out the synthesis of PET radiopharmaceuticals. TRIUMF has world-leading expertise in creating the initial quantities of radioisotopes and in combining them with biologically active molecules and compounds. Through partnerships with other researchers and clinicians in British Columbia and across Canada, TRIUMF scientists contribute to the overall understanding of human health.