News | February 11, 2008

PET More Accurate than CT for Detecting Lung Nodules

February 12, 2008 - Positron emission tomography (PET) was far more reliable than computed tomography (CT) in detecting whether or not a nodule was malignant, according to findings in a large, multi-institutional study comparing PET and CT in their accuracy in the characterization of lung nodules.

The researchers found that when PET and CT results were interpreted as "probably" or "definitely" benign, the results were "strongly associated with a benign final diagnosis," therefore, the modalities were equally good at making this determination. PET’s superior specificity (accuracy in characterizing a nodule as benign or malignant), however, resulted in correctly classifying 58 percent of the benign nodules that had been incorrectly classified as malignant on CT. Furthermore, when PET interpreted SPNs as definitely malignant, a malignant final diagnosis was 10 times more likely than a benign.

"CT and PET have been widely used to characterize solitary pulmonary nodules (SPNs) as benign or malignant," said James W. Fletcher, professor of Radiology at Indiana University School of Medicine in Indianapolis, IN. "Almost all previous studies examining the accuracy of CT for characterizing lung nodules, however, were performed more than 15 years ago with outdated technology and methods, and previous PET studies were limited by small sample sizes."

"Detecting and characterizing SPNs is important because malignant nodules represent a potentially curable form of lung cancer. Identifying which SPNs are most likely to be malignant enables physicians to initiate the proper therapy before local or distant metastases develop," said Fletcher.

In a head-to-head study addressing the limitations of previous studies, PET and CT images on 344 patients were independently interpreted by a panel of experts in each imaging modality, and their determination of benign and malignant nodules were compared to pathologic findings or changes in SPN size over the next two years.

SPNs are commonly encountered in both primary and specialty settings, often showing up on chest X-rays obtained for some other purpose than cancer screening and are often the first manifestation of lung cancer. The question for these patients then becomes whether to undergo surgery, undergo a needle biopsy or "watch and wait" to find out if the nodule is benign or malignant but treatable.

“In patients with an untreated and undiagnosed SPN between 7 and 30 millimeters, PET provides better identification of malignant nodules that require a more aggressive treatment approach,” said Fletcher. “PET in combination with CT can also provide good identification of those nodules that are most likely to be benign, suggesting that a ‘watch and wait’ strategy can be adopted in lieu of unnecessary invasive - and expensive - procedures such as needle biopsy or surgery,” he added.

For more information: http://www.snm.org

Related Content

PET Tracer Gauges Effectiveness of Promising Alzheimer's Treatment

Longitudinal PET imaging with 18F-AV45. PET imaging shows the average 18F-AV45 uptake per animal group at 8 and 13 months of age. A significant interaction of genotype treatment was observed in the cortex (p = 0.0248), hippocampus (p = 0.0071) and thalamus (p = 0.0084), indicating reduced [18F]-AV45 uptake in BACE1 inhibited transgenic mice. Credit: MICA, University of Antwerp, Belgium.

News | Radiopharmaceuticals and Tracers | December 28, 2017
In the December featured basic science article in The Journal of Nuclear Medicine, Belgian researchers report on the...
Michael J. Fox Foundation and Tau Consortium Developing PET Tracers for Neurodegenerative Disease
News | Radiopharmaceuticals and Tracers | October 27, 2017
The Michael J. Fox Foundation for Parkinson's Research (MJFF) and the Tau Consortium announced a funding partnership to...
SNMMI Publishes New FDG PET/CT Appropriate Use Criteria
News | PET-CT | October 25, 2017
The Society of Nuclear Medicine and Molecular Imaging (SNMMI) has published appropriate use criteria (AUC) for FDG PET/...
Majority of Recurrent Prostate Cancer Patients' Treatment Plan Changed Following Fluciclovine 18F PET/CT
News | Prostate Cancer | October 04, 2017
Blue Earth Diagnostics recently announced the results of a pre-planned interim analysis from an investigational...
Toshiba Highlights Latest CT Advancements at RSNA 2017
News | Computed Tomography (CT) | September 18, 2017
Toshiba Medical announced that it will display several new enhancements to its existing computed tomography (CT)...
Double Targeting Ligands to Identify and Treat Prostate Cancer

The mice were imaged with small-animal PET/CT using 124I-RPS-027 (7.4 MBq [200 μCi]). Credit: JM Kelly et al., Department of Radiology, Weill Cornell Medicine, New York, NY

News | Prostate Cancer | September 14, 2017
Researchers have demonstrated a new, effective way to precisely identify and localize prostate cancer tumors while...
Blue Earth Diagnostics Announcing Results of FALCON PET/CT Trial at ASTRO 2017
News | PET-CT | September 13, 2017
September 13, 2017 — Blue Earth Diagnostics announced the upcoming oral presentation of initial results from the FALC
FDG-PET/CT Predicts Melanoma Patients' Response to Immune Checkpoint Inhibitor Therapy
News | PET-CT | September 07, 2017
September 7, 2017 — Advanced melanoma has a poor prognosis, but immune checkpoint inhibitor therapy can be effective
Videos | Nuclear Imaging | August 24, 2017
Prem Soman, M.D., director of nuclear cardiology at the Heart and Vascular Institute, University of Pittsburgh, and p
ASNC and SNMMI Release Joint Document on Diagnosis, Treatment of Cardiac Sarcoidosis
News | Cardiac Imaging | August 18, 2017
August 18, 2017 — The American Society of Nuclear Cardiology (ASNC) has released a joint expert consensus document wi
Overlay Init