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

Abstract

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 >\u200980% concordance with good correlation (SUVmax κ\u2009=\u20090.71, SUVavg κ\u2009=\u20090.62, SUVsum κ\u2009=\u20090.62). Moderate correlation (κ\u2009=\u20090.43) 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\u2009=\u20090.52) 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.