Published on June 30th, 20170
St. Luke’s offers new type of PET/CT scan
New technology helps detect recurrent prostate cancer sooner
St. Luke’s University Health Network is among the first in the region to offer a new PET/CT scan for patients who have been treated for prostate cancer but who may be having a recurrence.
The scan uses the new molecular imaging agent recently approved by the U.S. Food and Drug Administration, Axumin™ (fluciclovine F-18). Axumin, a synthetic amino acid, can not only detect if disease is present but also its extent and how rapidly it is spreading. The results of the nuclear medicine scan can help determine the best course of follow-up treatment, said Dr. Frank Tamarkin, Chief of Urology at St. Luke’s.
“The sooner you treat someone for metastatic prostate cancer, the better your outcome is going to be,” Dr. Tamarkin said.
When men are diagnosed with primary prostate cancer, they often have surgery to remove the prostate (prostatectomy) and/or radiation therapy. After treatment, patients are monitored with periodic PSA (prostate specific antigen) blood tests, Dr. Tamarkin said. A rise in PSA levels after treatment indicates that the cancer has likely recurred. But the location of the recurrence is often difficult to determine, he said. “Recurrence occurs in one-quarter to one-third of treated patients,” Dr. Tamarkin said.
PET (positron emission tomography) is combined with CT (computerized tomography). PET/CT scans using fluorodeoxyglucose (FDG) work well for other cancers such as lung, breast and lymphoma, but until Axumin did not work as reliably for recurrent prostate cancer, said Dr. Edgar Cheng, Chief of Nuclear Medicine at St. Luke’s.
The PET/CT with Axumin is for patients who have been treated for prostate cancer but whose PSA is higher than 2, Dr. Tamarkin said. “PSA should be undetectable after prostatectomy,” Dr. Tamarkin explained. “Typically, after radiation the PSA goes below 1 and stays there.” Patients whose PSA is rising rapidly also might be candidates for the test, Dr. Cheng said.
The radioactive tracer is injected into the patient prior to his undergoing PET/CT imaging. If present, prostate cancer cells will absorb the radioactive tracer, Dr. Cheng said. When they do, they emit energy in the form of photons. The PET/CT scanner detects these photons while the computer produces detailed images of the patient’s anatomy and shows where metastatic disease may be – bone, pelvis and abdomen are the most likely, Dr. Cheng said. The patient is imaged from his head to his thighs.
Treatments for prostate cancer and metastatic disease have improved tremendously in the last few years, Dr. Tamarkin said. Being able to offer PET/CT scans to patients who were previously treated for prostate cancer who have rising PSA levels will improve the quality of their care and could increase survival, he said.
Prostate cancer is one of the most frequently diagnosed cancer in men. One in six men will be diagnosed with prostate cancer during his lifetime, according to the American Cancer Society. Guidelines from the American Urological Association recommend men of average risk begin screening age 55, Dr. Tamarkin said. Men should begin screening at 50 if they have risk factors such as a strong family history or are African American.