PT - JOURNAL ARTICLE AU - Arnoldo Piccardo AU - Francesco Paparo AU - Matteo Puntoni AU - Sergio Righi AU - Gianluca Bottoni AU - Lorenzo Bacigalupo AU - Silvia Zanardi AU - Andrea DeCensi AU - Giulia Ferrarazzo AU - Monica Gambaro AU - Filippo Grillo Ruggieri AU - Fabio Campodonico AU - Laura Tomasello AU - Luca Timossi AU - Simona Sola AU - Egesta Lopci AU - Manlio Cabria TI - <sup>64</sup>CuCl<sub>2</sub> PET/CT in Prostate Cancer Relapse AID - 10.2967/jnumed.117.195628 DP - 2018 Mar 01 TA - Journal of Nuclear Medicine PG - 444--451 VI - 59 IP - 3 4099 - http://jnm.snmjournals.org/content/59/3/444.short 4100 - http://jnm.snmjournals.org/content/59/3/444.full SO - J Nucl Med2018 Mar 01; 59 AB - Our objective was to evaluate the biodistribution, kinetics, and radiation dosimetry of 64CuCl2 in humans and to assess the ability of 64CuCl2 PET/CT to detect prostate cancer (PCa) recurrence in patients with biochemical relapse. Methods: We prospectively evaluated 50 PCa patients with biochemical relapse after surgery or external-beam radiation therapy. All patients underwent 64CuCl2 PET/CT, 18F-choline PET/CT, and multiparametric MRI within 15 d of each other. Experienced readers interpreted the images, and the detection rate (DR) of each imaging modality was calculated. Histopathology, when available; clinical or laboratory response; and multidisciplinary follow-up were used to confirm the site of disease. In parallel, biodistribution, kinetics of the lesions, and radiation dosimetry of 64CuCl2 were evaluated. Results: From a dosimetric point of view, an administered dose of 200 MBq for 64CuCl2 translated into a 5.7-mSv effective dose. Unlike 18F-choline, 64CuCl2 was not excreted or accumulated in the urinary tract, thus allowing thorough pelvic exploration. The maximum 64CuCl2 uptake at the sites of PCa relapse was observed 1 h after tracer injection. In our cohort, 64CuCl2 PET/CT proved positive in 41 of 50 patients, with an overall DR of 82%. The DRs of 18F-choline PET/CT and multiparametric MRI were 56% and 74%, respectively. The difference between the DRs of 64CuCl2 PET/CT and 18F-choline PET/CT was statistically significant (P &lt; 0.001). Interestingly, on considering prostate-specific antigen (PSA) value, 64CuCl2 PET/CT had a higher DR than 18F-choline PET/CT in patients with a PSA of less than 1 ng/mL. Conclusion: The biodistribution of 64CuCl2 is more suitable than that of 18F-choline for exploring the pelvis and prostatic bed. The 64CuCl2 effective dose is like those of other established PET tracers. In patients with biochemical relapse and a low PSA level, 64CuCl2 PET/CT shows a significantly higher DR than 18F-choline PET/CT.