Fabio Almeida MD, Presenter: Nothing to Disclose

Mark Scholz MD, Abstract Co-Author: Nothing to Disclose

Richard Lam MD, Abstract Co-Author: Nothing to Disclose

Jeffrey Turner MD, Abstract Co-Author: Nothing to Disclose

Charles Myers MD, Abstract Co-Author: Nothing to Disclose

Elisa Blackwell, Abstract Co-Author: Nothing to Disclose

This study compared C11-Acetate (CA) positron emission tomography (PET/CT) and F18 Sodium Fluoride (F18-NaF) PET bone imaging for the detection of skeletal metastasis in men with biochemically recurrent PCa.

Men with PCa  previously having had definitive therapy demonstrating a rising PSAs were evaluated retrospectively. CA PET/CT studies where performed and F18-NaF PET performed within 2 months was compared. Imaging studies were reviewed for the presence/absence of skeletal lesions, and for concordance in the number of detected lesions. Detection rates of soft tissue lesions was also evaluated on the CA PET studies in relation to the presence/absence of skeletal lesions. PSA kinetics were evaluated.

183 studies (men age 45 – 88) met our criteria for image review. PSA ranged from 0.5 – 148 (median 2.5). CA PET detected skeletal lesions in 59 (32%) of studies, whereas F18-NaF PET detected lesions in 75 (41%). In 22 studies, CA PET and F18-NaF where concordant, demonstrating a solitary bony lesion in 14 and multiple bony lesions in 7. 57 studies were discordant. F18-NaF PET demonstrated lesions not seen on CA PET in 36 (20%) studies (median PSA 3.05, median PSA doubling time[dt] 4 months). CA PET found bony lesions in 14 studies (8%) not present on the F18-NaF studies. In 7 studies there were non-specific findings on the F18-NaF study that where negative on the CA PET and therefor felt to be benign. In studies positive for bony lesions, CA PET additionally identified soft tissue lesions in 31 (17%) studies. In 78 (42%) studies CA PET identified soft tissue lesions when no bone lesions where found on either CA PET or F18-NaF (median PSA 2.36, median PSAdt 5 months). These lesions were found to be in the pelvis in 61 (33%), extrapelvic regions in 6 (3%) and involving both pelvic and extrapelvic soft tissue sites in 11 (6%).

CA PET and F18-NaF PET are useful and appear complimentary for the detection of skeletal metastasis in patients with biochemical recurrence of PCa, but do show discordance in their detection rates. CA PET also detected soft tissue lesions in most patients negative for bone lesions. PSA kinetics do not appear to help select one imaging study over the other.

PCa recurrence after definitive treatment occurs in up to 40% of patients. Conventional imaging is of limited value in detection in early biochemical recurrence, thereby limiting treatment options.

Almeida, F, Scholz, M, Lam, R, Turner, J, Myers, C, Blackwell, E, C11-Acetate PET/CT and F18 Sodium FluoridePET Bone Imaging in the Detection of Skeletal Metastasis in Biochemically Recurrent Prostate Adenocarcinoma (PCa).  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14009237.html