Digital PET detects smaller cancerous lesions, produces images nuclear medicine experts prefer

Digital positron emission tomography can detect smaller abnormalities and is preferred by nuclear medicine experts when compared to high-resolution PET, according to a new study.

A team of Dutch researchers came to that conclusion after a prospective head-to-head comparison revealed the digital modality detected nearly 40 potentially cancerous lesions that were considered unmeasurable or invisible using conventional PET. Further investigations are needed to confirm its superior diagnostic performance, but the initial results utilizing this new approach are encouraging.

The findings, led by first author Daniëlle Koopman, PhD, with Technical Medicine Center in the Netherlands, were published Feb. 14 in the Journal of Nuclear Medicine.

PET modalities using silicon photomultipliers with digital readouts are relatively new, the authors noted. And compared to traditional scanners, these digital PET systems have better spatial and timing resolution, which has been proven to yield higher-quality images with increased standardized uptake values.

Given that PET imaging, using the radiopharmaceutical fluorodeoxyglucose (FDG), is becoming increasingly important to diagnosing, monitoring and treating cancer, Koopman et al. sought to better understand how the digital modality compared to its traditional counterpart in patients with various forms of the disease.

Unlike previous studies, the group compared both conventional and digital PET using high-resolution reconstructions. This approach has been shown to significantly improve the legacy modality, but its impact is less understood when applied to the digitized version.

Koopman and colleagues injected 66 patients with the FDG agent and performed both digital and conventional PET imaging in each individual. Two nuclear medicine specialists reviewed the scans for lesions and rated image quality.

Overall, digital PET was able to detect more lesions, changed patients' diagnosed stage of cancer and produced images that were preferred by the two experts. Specifically, the novel modality found 37 additional lesions in 27 patients that did not show up on conventional scans. And in 65% of cases, the specialists preferred digital PET-produced images.

Future studies will be needed to confirm the superiority of this new approach, the authors noted. But depending on those results, digital PET may become big news in the field of oncology.

“With improved small lesion detection and upstaging in some cases, digital PET may provide a more accurate diagnosis compared to conventional PET and this could influence patient treatment and prognosis,” Koopman and colleagues concluded.