Accurate knowledge of the biodistribution of 18F-choline is essential for the correct interpretation of PET/CT imaging. CT enables differentiation of physiological bowel activity and 18F-choline excretion in the ureters. In our series, 18F-choline uptake in benign pathological conditions mainly included sites of inflammation; nevertheless, accumulation in tumour deposits not because PC cannot be excluded, particularly in the brain, where correlative imaging with magnetic resonance is of the utmost importance.

Detection rate of (18)F-choline imaging is closely related to PSA and PSA kinetics. In particular, (18)F-choline PET/CT is recommended in patients with PSA >2 ng/ml, PSAdt ≤6 months and PSAve >2 ng/ml per year. CT is useful for detecting bone metastases that are not (18)F-choline-avid. The use of intravenous contrast agent seems unnecessary.

Our results support the conclusion of a very limited impact of ABVD chemotherapy on brain metabolism in patients with HD.