Combined PET-CT better at detecting metastases.(of ovarian cancer)

2003 JAN 2 - (NewsRx.com & NewsRx.net) -- Hopkins radiologists have found that a combination of positron emission tomography (PET) and computed tomography (CT) detects cancer spread better than PET alone.

In a study presented at a recent meeting of the Radiological Society of North America, researchers reported that overall, PET-CT improves the ability to distinguish cancerous from normal tissue and locate metastases. The study used a scanner that fuses CT technology, which provides anatomical detail, with PET images, which detects metabolic activity of tumors.

Ten PET and 33 PET-CT scans were performed on 28 patients with ovarian cancer suspected to have spread to the abdominal cavity. There were 3 true positive and 2 true negative results with PET alone and 14 true positives and 10 true negatives with PET-CT. The PET scan alone produced 2 false-positives, while PET-CT produced none. There were no false-negatives with PET alone, and PET-CT had 5. Combined PET-CT had a fairly high sensitivity rate, accurately diagnosing cancer 73.6% of the time (14 of 19), and PET alone was able to diagnose all 3 positive cancers.

"PET-CT was very specific, as it was able to distinguish cancer from noncancer 100% of the time (10 of 10), while PET alone was specific for cancer only 50% of the time (2 of 4)," said Richard L. Wahl, MD, the Henry N. Wagner Jr. professor of nuclear medicine and director of the division of nuclear medicine at Johns Hopkins. Routine contrast-enhanced CT was able to find disease in 3 of the 5 ...