Treatment Response Assessment of Skeletal Metastases in Prostate Cancer with 18F-NaF PET/CT.

To determine the utility of 18F-sodium fluoride positron emission tomography-computed tomography (18F-NaF PET/CT) in the imaging assessment of therapy response in men with osseous-only metastatic prostate cancer.

In this Institutional Review Board-approved single institution retrospective investigation, we evaluated 21 18F-NaF PET/CT scans performed in 14 patients with osseous metastatic disease from prostate cancer and no evidence of locally recurrent or soft-tissue metastatic disease who received chemohormonal therapy. Imaging-based qualitative and semi-quantitative parameters were defined and compared with changes in serum PSA level.

Qualitative and semi-quantitative image-based assessments demonstrated > 80% concordance with good correlation (SUVmax κ = 0.71, SUVavg κ = 0.62, SUVsum κ = 0.62). Moderate correlation (κ = 0.43) was found between SUVmax and PSA-based treatment response assessments. There was no statistically significant correlation between PSA-based disease progression and semi-quantitative parameters. Qualitative imaging assessment was moderately correlated (κ = 0.52) with PSA in distinguishing responders and non-responders.

18F-NaF PET/CT is complementary to biochemical monitoring in patients with bone-only metastases from prostate cancer which can be helpful in subsequent treatment management decisions.

Nuclear medicine and molecular imaging. 2019 Jun 24 [Epub]

Erik M Velez, Bhushan Desai, Hossein Jadvar

Division of Nuclear Medicine, Department of Radiology, Keck School of Medicine, University of Southern California, 2250 Alcazar St., CSC 102, Los Angeles, CA 90033 USA.