TY - JOUR T1 - Effects of Fasting on <sup>18</sup>F-DCFPyL Uptake in Prostate Cancer Lesions and Tissues with Known High Physiologic Uptake JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1081 LP - 1084 DO - 10.2967/jnumed.117.207316 VL - 59 IS - 7 AU - Maurits Wondergem AU - Friso M. van der Zant AU - Peter W. Vlottes AU - Remco J.J. Knol Y1 - 2018/07/01 UR - http://jnm.snmjournals.org/content/59/7/1081.abstract N2 - In the literature, a 4- to 6-h fast is recommended before a patient undergoes PET/CT with 2-(3-(1-carboxy-5-[(6-18F-fluoro-pyridine-3-carbonyl)-amino]-pentyl)-ureido)-pentanedioic acid (18F-DCFPyL); however, a scientific underpinning for this recommendation is lacking. Therefore, we performed a study to determine the impact of fasting on 18F-DCFPyL uptake. Methods: The study included 50 patients who fasted at least 6 h before 18F-DCFPyL administration and 50 patients who did not. Activity (SUVmax) was measured in lesions characteristic of prostate cancer and in normal tissues known to express high physiologic uptake. Results: Uptake in suspected lesions did not differ between the cohorts. 18F-DCFPyL uptake in the submandibular gland, liver, and spleen was significantly higher in the fasting than the nonfasting cohort. Conclusion: Our data show that fasting does not significantly affect 18F-DCFPyL uptake in suspected malignant lesions but does result in significantly lower 18F-DCFPyL uptake in tissues with high physiologic uptake. The absolute differences in uptake were relatively small; therefore, the effects of fasting on the diagnostic performance can be considered negligible. ER -