A Prospective Comparison of 18 F-Sodium Fluoride PET/CT and PSMA-Targeted 18 F-DCFBC PET/CT in Metastatic Prostate Cancer

J Nucl Med. 2018 Nov;59(11):1665-1671. doi: 10.2967/jnumed.117.207373. Epub 2018 Mar 30.

Abstract

The purpose of this study was to compare the diagnostic performance of 18F-DCFBC PET/CT, a first-generation 18F-labeled prostate-specific membrane antigen (PSMA)-targeted agent, and 18F-NaF PET/CT, a sensitive marker of osteoblastic activity, in a prospective cohort of patients with metastatic prostate cancer. Methods: Twenty-eight prostate cancer patients with metastatic disease on conventional imaging prospectively received up to 4 PET/CT scans. All patients completed baseline 18F-DCFBC PET/CT and 18F-NaF PET/CT scans, and 23 patients completed follow-up imaging, with a median follow-up interval of 5.7 mo (range, 4.2-12.6 mo). Lesion detection was compared across the 2 PET/CT agents at each time point. Detection and SUV characteristics of each PET/CT agent were compared with serum prostate-specific antigen (PSA) levels and treatment status at the time of baseline imaging using nonparametric statistical testing (Spearman correlation, Wilcoxon rank). Results: Twenty-six patients had metastatic disease detected on 18F-NaF or 18F-DCFBC at baseline, and 2 patients were negative on both scans. Three patients demonstrated soft tissue-only disease. Of 241 lesions detected at baseline, 56 were soft-tissue lesions identified by 18F-DCFBC only and 185 bone lesions detected on 18F-NaF or 18F-DCFBC. 18F-NaF detected significantly more bone lesions than 18F-DCFBC (P < 0.001). Correlation of PSA with patient-level SUV metrics was strong in 18F-DCFBC (ρ > 0.5, P < 0.01) and poor in 18F-NaF (ρ < 0.3, P > 0.1). When PSA levels were combined with treatment status, patients with below-median levels of PSA (<2 ng/mL) on androgen deprivation therapy (n = 11) demonstrated more lesions on 18F-NaF than 18F-DCFBC (P = 0.02). In PSA greater than 2 ng/mL, patients on androgen deprivation therapy (n = 8) showed equal to or more lesions on 18F-DCFBC than on 18F-NaF. Conclusion: The utility of PSMA-targeting imaging in metastatic prostate cancer appears to depend on patient disease course and treatment status. Compared with 18F-NaF PET/CT, 18F-DCFBC PET/CT detected significantly fewer bone lesions in the setting of early or metastatic castrate-sensitive disease on treatment. However, in advanced metastatic castrate-resistant prostate cancer, 18F-DCFBC PET/CT shows good concordance with NaF PET/CT.

Keywords: NaF; PET/CT imaging; PSMA; metastatic prostate cancer.

Publication types

  • Clinical Trial, Phase I
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antigens, Surface / metabolism*
  • Bone Neoplasms / diagnostic imaging
  • Bone Neoplasms / secondary
  • Cysteine / analogs & derivatives*
  • Fluorine Radioisotopes*
  • Glutamate Carboxypeptidase II / metabolism*
  • Humans
  • Male
  • Middle Aged
  • Positron Emission Tomography Computed Tomography / methods*
  • Prospective Studies
  • Prostatic Neoplasms / diagnostic imaging*
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology
  • Radiopharmaceuticals*
  • Soft Tissue Neoplasms / diagnostic imaging
  • Soft Tissue Neoplasms / metabolism
  • Soft Tissue Neoplasms / secondary

Substances

  • Antigens, Surface
  • Fluorine Radioisotopes
  • N-(N-((S)-1,3-Dicarboxypropyl)carbamoyl)-4-(18F)fluorobenzyl-L-cysteine
  • Radiopharmaceuticals
  • FOLH1 protein, human
  • Glutamate Carboxypeptidase II
  • Fluorine-18
  • Cysteine