Several imaging modalities currently exist for detection of metastases with different performance characteristics for skeletal and extraskeletal metastases. The combined administration of 18F-NaF and 18F-FDG (18F-/18F-FDG) in a single PET/CT scan for cancer detection has been proposed for detecting both extraskeletal and skeletal lesions.
A recent study published by Minamimoto et al. in the Journal of Nuclear Medicine compared this imaging technique with 99mTc MDP bone scintigraphy (BS) and whole-body MRI (WBMRI) in patients with breast and prostate cancers (15 patients in each group) who were referred for standard BS. Each patient underwent imaging with all three modalities and the findings were compared.
The study showed no statistically significant differences between 18F-/18F-FDG PET/CT and WBMRI in sensitivity (92.9% vs 92.9%, P = 1.00) for extra-skeletal lesions. On the other hand, 18F-/18F-FDG PET/CT showed significantly superior sensitivity and accuracy to either WBMRI or BS (96.2% vs 64.6%, P<0.001, 89.8% vs 65.9%, P<0.001) for the identification of skeletal lesions. Overall, 18F-/18F-FDG PET/CT performed similarly to a combination of WBMRI and BS in these patients.
While very promising, the results of this interesting study will require confirmation in a larger cohort of patients. If confirmed, these findings will have important implications for providing a single imaging modality for detection of both skeletal and visceral metastases in prostate cancer patients.
Andrei Iagaru, Ryogo Minamimoto, Camila Mosci, Mehran Jamali, Amir Barkhodari, Andreas Loening, Valentina Taviani, Erik Mittra, Sanjiv Gambhir, and Shreyas Vasanawala. Prospective evaluation of 99mTc MDP scintigraphy, 18F NaF/18F FDG PET/CT and WBMRI in patients with breast and prostate cancers J Nucl Med 2015 56:1305
Commenatry written by: Bishoy Faltas Dr. Bishoy Faltas is a medical oncologist in New York, New York and is affiliated with New York-Presbyterian University Hospital of Columbia and Cornell.