A high GS at diagnosis is a strong predictive factor for positive (18)F-choline PET/CT scan results for recurrent PCa, even when the PSA level is low (i.e., ≤1 ng/mL).

FDG PET/CT is more sensitive than CT and CA 15.3 in the evaluation of disease relapse. PET/CT might be considered a complementary imaging technique during follow-up in patients with breast cancer.

The current experience confirms the potential of fluorodeoxyglucose PET, and in particular of PET/CT, in detecting occult soft tissue and bone metastases in the presence of a progressive increase of serum tumor markers in BC patients, but this should be better defined in the current practical recommendations.