In addition to the dramatic impact on surgical patients, PET scans also had an impact on patients for whom radiotherapy was planned but who subsequently did not receive the treatment. Because of the PET scans, surgery or radiotherapy was initiated for 18 patients.
PET was also able to allay concerns. For five of the patients with suspicious findings on conventional imaging, PET scans were found to be normal, and follow-ups indicated no recurrence.
One of PETs traditional strengths has been its ability to detect disease before it is visible on other imaging modalities but where other indications, such as rising CEA levels, suggest that disease is recurring somewhere in the body. The study reiterated this point: Overall, 12% of the patients were moved from observation to active treatment and 10 of the12 patients had rising markers.
The authors cautioned that PET scans did have some limitations. In a small number of cases, while PET identified that disease was present, it underestimated the extent of the disease as revealed by later treatment or invasive surgery. There were also 4 false-negative findings, which the authors attribute primarily to the small size, <1cm, of the lesions.
The study examined the PET scans and treatment progress of 96 patients who were referred for PET, and for whom their physicians had indicated a proposed treatment plan based on their current (pre-PET) status, and an additional
Contact: Karen Lubieniecki
Society of Nuclear Medicine