Use of choline tracers in the prostate carcinoma management

Prostate cancer is the second most frequently diagnosed cancer in men. This incidence has increased because of the introduction of screening with prostate-specific antigen (PSA) and the use of improved biopsy techniques. Choline PET/CT cannot be recommended as a first-line screening procedure for primary prostate cancer. PET/CT has a limited sensitivity due to its dependency on tumor configuration and size, and a limited specificity in differentiation between prostate cancer and benign pathologies. PET/CT could be useful in the detection of malignant lymph nodes in case of nodes greater than 5 mm in diameter. An application of choline PET/CT may be to increase the detection rate of clinically suspected prostate cancer with multiple negative prostate biopsies. Choline PET/CT has proved to be useful for restaging patients with prostate cancer with biochemical failure. Studies have shown that the positive detection rate of choline PET/CT increases with increasing PSA values. The definition of a PSA cut-off value to refer prostate carcinoma with biochemical recurrence would be helpful for the clinical management of these patients. Several PSA cut-off values have been proposed by literature. The routine use of choline PET/CT cannot be recommended only in patients with an absolute PSA value of < 1 ng/mL. Moreover, the sensitivity of ¹⁸F-Fluorocholine (FCH) PET/CT is significantly higher in patients with a PSA velocity > 2 ng/mL per year or a PSA-doubling time ≤ 6 months. In case of early bone metastases ¹⁸F-FCH could be superior to ¹⁸F-sodium fluoride due to the absence of bone reaction and remodelling.