By Amber Hair

Staff writer

Decades of preparation have gone into making Ridley-Tree Cancer Center a leader in the field of nuclear medicine, and Drs. Bill Pace and Dave Carlson are working hard to keep it there.

Nuclear medicine is the use of radioactive materials to diagnose and treat diseases. At Ridley-Tree, Pace and Carlson are using a new radioactive tracer to find and treat prostate cancer earlier and more effectively.

“We’ve been waiting for this moment in nuclear cancer for a long time,” Pace said.

With the tracer, Pylarify, the doctors can use low-energy isotopes to detect cancer in its earlier stages and then take pictures of what’s going on — if a tumor is growing or shrinking, if it’s spreading to other tissues or if it’s still contained in a single area. 

They can then use a higher-energy version of the tracer to treat the cancer with monthly injections that deliver more radiation to the cancerous cells and less radiation to the healthier cells.

This takes away a lot of the investigative work that often comes with cancer care. People with the same diagnoses don’t always respond to the same treatments, which means that doctors and patients often have to work together to find one therapy that will work out of a variety of options.

With Pylarify, Pace said, “We know how the therapy is going to work because we took photos of the chemistry.” 

As a result, patients suffer fewer comorbidities and complications. More traditional cancer treatments can often ride the line between curing cancer and causing such taxing side effects that the patient has to stop treatment early.

“We’re hoping to take a quantum leap in both fighting (prostate cancer) and treating it,” Carlson said.

Pylarify was approved by the FDA in 2021, but it still has relatively limited availability. A therapy like this is usually only offered in large academic centers, which means that if it weren’t available in Santa Barbara, people would have to go to Los Angeles or San Francisco to get the treatment.

Pace and Carlson are both leaders in their field, and they’ve got the credentials to prove it. Carlson is part of the Society for Nuclear Medicine and Molecular Imaging, and he regularly donates time to go back to UC San Francisco, where he received graduate medical education, to teach nuclear medicine to others.

Pace was among the earliest group of doctors to be trained in nuclear medicine at Stanford University, where he had both a residency and a fellowship in nuclear medicine. Both doctors are also certified by the American Board of Nuclear Medicine.

Jill Fonte, the spokeswoman for Sansum Clinic, Ridley-Tree’s parent organization, said their expertise in the field is one of the key factors that sets Ridley-Tree part from cancer centers in other similarly sized communities.

“The doctors’ extensive education and experience in interpreting nuclear medicine studies allow them to notice more subtle abnormalities that might potentially go unnoticed or perhaps missed by less experienced readers and physicians,” Fonte said. “It is a rarity to find two nuclear medicine physicians with these qualifications in a community of this size.”

Both doctors credit Ridley-Tree’s long-term commitment to staying at the forefront of nuclear medicine. The nuclear medicine department has more than 20 people, including doctors, nuclear medicine technicians, nurses and other staff, and it has earned accreditation by the Intersocietal Accreditation Commission in the areas of nuclear cardiology, general nuclear medicine and positron emission technology.

“This is not something that pops up overnight,” Pace said.