New PET tracers reveal the presence of tumors that were difficult to see before.
"We're particularly excited about Dototate, a peptide that binds to somatostatin receptors," said Jonathan McConathy, MD, PhD, Director of the Division of Molecular Imaging and Therapeutics at UAB. "It's a type tracer that we refer to as a theranostic, combining both diagnostic and therapeutic properties. In addition to helping us detect neuroendocrine cancers, it is available in a form that delivers targeted radiation to malignant cells in a type of cancer that often has few other treatment options."
Another area where current research is improving diagnosis and treatment is in prostate cancer.
"Different PET tracers bind to receptors in different types of tumors. Agents used with other types of cancer haven't worked with prostate tumors, but our researchers are working with Fluciclovine, an amino acid tracer that shows high uptake in prostate cancer cells," McConathy said. "Since it helps to detect which lymph nodes are involved, it should help to improve outcomes. It could also help some patients with less advanced cancers avoid the need for surgery."
A new estradiol tracer awaiting FDA approval could be helpful in monitoring estrogen in women with metastatic breast cancer. Another advance already available at UAB combines PET scans with a simultaneous MRI.
"Most of the time we're combining simultaneous PET and CT to give us a clearer view of what's going on, the morphology and more diagnostic information. But there are certain types of cancers where an MRI can tell us more. Now we have the option of using a simultaneous PET scan and MRI when needed," McConathy said.
For some time now, tracers have allowed precision targeting of tumors for both radiotherapy and surgery. New agents are now being developed that will allow monitoring of T-cells and other elements of the immune system. This should offer major advantages in tracking immune therapies used against cancer. It also has great potential for assisting in research into disorders that arise from the immune system.
Drug development is another area where new and better tracers are moving health care forward.
"Agents that track a drug could show where it is active and whether it crosses the blood brain barrier or reaches another target area. It could save months of delay and help researchers fine tune the optimum approach to drug delivery," McConathy said. "In clinical trials, researchers could see if the drug is getting where it needs to be without the need for biopsy or waiting six months or more to see how participants are doing."
Beyond molecular imaging where McConathy focuses most of his efforts, other advances in imaging are playing a role in both research and better patient care.
"Real time fluorescence allows surgeons to see the margins of tumors as they operate so they can remove the cancer with good margins," he said. "As we develop new and better tracer agents, we should continue to improve the ability to precision target therapies."
Many of the advances in imaging are also making a difference in other types of conditions such as neurological and cardiovascular disorders.
"A tracer that attaches to infected heart cells shows us whether an infection is present and exactly which areas need treatment," McConathy said. "There is no need for the risk of a biopsy or the chance of missing the right area.
"Another wonderful thing about PET agents, especially compared to other forms of imaging, is that such a very small mass of tracer is necessary that we rarely, if ever, see side effects or allergic reactions. It's just about unheard of."
McConathy also emphasized UAB's commitment to making its advanced imaging technologies accessible to the people of Alabama and making the PET tracers it produces available to other imaging sites around the state.
"It's an exciting time for molecular imaging and therapy," he said. "As more new tracers are developed and approved for use, precision care for patients will continue to improve."
