PT - JOURNAL ARTICLE AU - Ana E. Brito AU - Felipe Mourato AU - Allan Santos AU - Camila Mosci AU - Celso Ramos AU - Elba Etchebehere TI - Validation of the Semiautomatic Quantification of <sup>18</sup>F-Fluoride PET/CT Whole-Body Skeletal Tumor Burden AID - 10.2967/jnmt.118.211474 DP - 2018 Dec 01 TA - Journal of Nuclear Medicine Technology PG - 378--383 VI - 46 IP - 4 4099 - http://tech.snmjournals.org/content/46/4/378.short 4100 - http://tech.snmjournals.org/content/46/4/378.full SO - J. Nucl. Med. Technol.2018 Dec 01; 46 AB - Our purpose was to validate a semiautomatic quantification of the skeletal tumor burden on 18F-fluoride PET/CT using manual quantification as a reference. Methods: We quantified 51 18F-fluoride PET/CT examinations performed on female breast cancer patients. Clinical information (age; time of disease presentation; presence of visceral metastases; and time to death, progression, or a bone event) was recorded. The total volume of 18F-fluoride–avid skeletal metastases and the total activity of 18F-fluoride–avid metastases were calculated manually and semiautomatically. Results: Manual and semiautomatic metrics correlated strongly (P &lt; 0.0001; 95% confidence interval, 0.9300–0.9769). On multivariable analysis, the semiautomatic measures of total activity for 18F-fluoride–avid metastasis correlated significantly with overall survival (P = 0.0001) and progression-free survival (P = 0.0006). Approximate times for calculating skeletal tumor burden (semiautomatic vs. manual) were, respectively, 30 s versus 321 s in patients with fewer than 5 metastases, 120 s versus 640 s in patients with 5–10 metastases, and 240 s versus 1207s in patients with more than 10 metastases. Conclusion: Semiautomatic quantification of whole-body 18F-fluoride PET/CT skeletal tumor burden can replace manual quantification in breast cancer patients and is a strong independent biomarker of prognosis.