Comparison of NaF and FDG PET/CT for assessment of treatment response in castration-resistant prostate cancers with osseous metastases.

Abstract

BACKGROUND:

Assessment of skeletal metastases' response to therapy is a highly relevant but unresolved clinical problem. The main goal of this work was to compare pharmacodynamic responses to therapy assessed with positron emission tomography-computed tomography (PET/CT) using fluorine-18 sodium fluoride (NaF) and fluorine-18 fluorodeoxyglucose (FDG) as the tracers.

MATERIALS AND METHODS:

Patients with prostate cancer with known osseous metastases were treated with zibotentan (ZD4054) and imaged with combined dynamic NaF/FDG PET/CT before therapy (baseline), after 4 weeks of therapy (week 4), and after 2 weeks of treatment break (week 6). Kinetic analysis allowed comparison of the voxel-based tracer uptake rate parameter Ki, the vasculature parameters K1 (measuring perfusion/permeability) and Vb (measuring vasculature fraction in the tissue), and the standardized uptake values (SUVs).

RESULTS:

Correlations were high for the NaF and FDG peak uptake parameters (Ki and SUV correlations ranged from 0.57 to 0.88) and for vasculature parameters (K1 and Vb correlations ranged from 0.61 to 0.81). Correlation was low between the NaF and FDG week 4 Ki responses (ρ = 0.35; P = .084) but was higher for NaF and FDG week 6 Ki responses (ρ = 0.72; P < .0001). Correlations for vasculature responses were always low (ρ < 0.35). NaF and FDG uptakes in the osseous metastases were spatially dislocated, with overlap in the range from 0% to 80%.

CONCLUSION:

This study found that late NaF and FDG uptake responses are consistently correlated but that earlier uptake responses and all vasculature responses can be unrelated. This study also confirmed that FDG and NaF uptakes are spatially dislocated. Although treatment responses assessed with NaF and FDG may be correlated, using both tracers provides additional information.

• Authors: Urban Simoncic, Scott Perlman, Glenn Liu, Mary Jane Staab, Jane Elizabeth Straus, Robert Jeraj
• Journal: Clinical genitourinary cancer (Clin Genitourin Cancer) Vol. 13 Issue 1 Pg. e7-e17 (Feb 2015) ISSN: 1938-0682 [Electronic] United States
• PMID: 25128349 (Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical References

• Pyrrolidines
• ZD4054
• Fluorodeoxyglucose F18
• Sodium Fluoride

Topics

• Aged
• Aged, 80 and over
• Bone Neoplasms (drug therapy, secondary)
• Clinical Trials, Phase III as Topic
• Fluorodeoxyglucose F18
• Humans
• Male
• Middle Aged
• Positron-Emission Tomography
• Prostatic Neoplasms, Castration-Resistant (drug therapy, pathology)
• Pyrrolidines (administration & dosage)
• Sodium Fluoride
• Tomography, X-Ray Computed
• Treatment Outcome