Background: (18)F-fluorocholine PET/CT is used to detect lymph node metastases in prostate cancer patients. Physiological (18)F-fluorocholine in the gastrointestinal tract, especially in the intestines, may interfere with the detection of malignant lymph nodes. Fasting is frequently proposed in literature; however, scientific support is lacking. This study aims to determine the impact of fasting on (18)F-fluorocholine uptake in the gastrointestinal tract.
Methods: Eighty patients were studied, 40 fasted for at least 6 h prior to (18)F-fluorocholine administration while the other 40 did not fast. (18)F-fluorocholine uptake pattern and intensity were evaluated in the intestine near the abdominal aorta and four regions near the iliac arteries. (18)F-fluorocholine intensity was also measured in the liver, pancreas, stomach and spleen.
Findings: No statistically significant differences were found in (18)F-fluorocholine uptake in the gastrointestinal tract between the fasting and non-fasting group.
Conclusions: Fasting for 6 h has no effect on (18)F-fluorocholine uptake in the gastrointestinal tract. Therefore, no effects on the detection of malignant lymph nodes are expected, and fasting is not recommended in our opinion.
Keywords: 18F-fluorocholine; PET/CT; Patient preparations; Prostate cancer; Urology.