Positron emission tomography with c11-acetate for tumor detection and localization in patients with prostate-specific antigen relapse after radical prostatectomy

To evaluate positron emission tomography with C11-acetate as a method for detecting and localizing prostate cancer recurrence. No technique for localizing and detecting prostate cancer recurrence after biochemical relapse available today is sensitive enough to localize recurrence at a stage at which salvage radiotherapy is still curative. Twenty patients (age 56 to 77 years) who had undergone radical prostatectomy and had an increasing prostate-specific antigen level measured on two consecutive occasions were included. In addition to the investigations usually performed when prostate cancer recurrence is suspected, they underwent positron emission tomography with C11-acetate as the marker. Pathologic uptake of acetate was seen in 15 (75%) of the 20 patients. In 8 of these patients, a solitary lesion was found (seven in the prostatic fossa and one at the regional lymph nodes). Multiple lesions were found in the remaining 7. False-positive uptake was seen in 3 men (15%). Additional investigations in these men revealed pathologic findings other than prostate cancer. Positron emission tomography with C11-acetate as marker is a promising method for early detection and localization of prostate cancer recurrence. False-positive uptake does occur.