Defiance Clinic now offers test for staging some types of cancer

Defiance Clinic now offers an advanced imaging technique that aids physicians in the treatment of certain types of cancer.

The new technique combines PET (positron emission tomography) with CT (computed tomography) in a technique called PET/CT fusion imaging. The test is used to determine if and where some cancers have spread, a process called staging. Doctors use this information to plan treatment.

The mobile equipment brought to the Clinic by Alliance Imaging, Inc., of Canton, OH, first makes a PET scan, immediately followed by a CT scan. A computer program then combines the two images to pinpoint a precise location for the cancer.

PET produces a visual image of the rate at which cells are using blood sugar (glucose). Cancer cells metabolize blood glucose at a higher rate than normal cells. Cancerous activity shows up as hot spots on the PET images, explained James P. Eisenberg, M.D., radiologist at the Clinic.

Common forms of cancer that can be staged with PET include those of the lung, breast and colon as well as lymphoma and some others.

“In cancer patients, changes in cell metabolism sometimes occur before a tumor mass is large enough to be found on physical examination or by CT or MRI (magnetic resonance imaging) used alone. PET can often identify where cancer is spreading or metastasizing earlier,” Dr. Eisenberg said.

“The PET scan gives us an image of the body’s physiology, of how the cells are functioning at the molecular level. The CT scan gives us an image of the anatomy, the physical structures of the body. By superimposing the PET image over the CT image, we get a detailed view of what is happening and where it is happening,” he explained.

“We are able to give the patient’s oncologist the full story—not just that cancer is present, but where it is and how aggressive it is. That information helps in choosing the most appropriate treatment,” he said.

Once a patient has been accurately staged and treatment has begun, the combined scan can be used for some types of cancers to monitor the effectiveness of the therapy.

“Repeat scans give the patient’s oncologist valuable feedback. If a treatment is not having the desired result, PET/CT fusion will quickly let the oncologist know so appropriate adjustments can be made,” Dr. Eisenberg said. “Although this new technology is not perfect and does occasionally produce false positives, it truly allows us to practice medicine at the molecular level. PET/CT fusion is a quantum jump ahead in healthcare delivery.”

PET/CT fusion uses a safe, short-lived radioactive isotope, injected about 45 minutes before the scan. Blood glucose levels should be checked before the isotope is injected. There are no known side effects from the radioactive tracer. Patients can resume their normal activities immediately after it is completed.