Operational characteristics of ¹¹C-choline positron emission tomography/computerized tomography for prostate cancer with biochemical recurrence after initial treatment

Purpose: We examined the performance of ¹¹C-choline positron emission tomography/computerized tomography for its ability to delineate prostate cancer distribution and extent after initial therapy. Materials and Methods: A consecutive series retrospective review was performed of all patients with prostate cancer who were evaluated using ¹¹C-choline positron emission tomography/computerized tomography from September 2007 to November 2010 at the Mayo Clinic. Statistical analysis was performed to determine the sensitivity, specificity, positive predictive value, negative predictive value and prostate specific antigen threshold for the detection of recurrent lesions. Results: In the study period 176 patients with biochemical recurrence after primary treatment failure underwent ¹¹C-choline positron emission tomography/computerized tomography. Using patient based analysis ¹¹C-choline positron emission tomography yielded a sensitivity, specificity, positive predictive value and negative predictive value of 93%, 76%, 91% and 81%, respectively. Of the 176 positron emission tomography/computerized tomography scans performed 56 (32%) were deemed clinically useful as defined by the ability to identify lesions not delineated using conventional imaging, thereby prompting changes in clinical management. The optimal prostate specific antigen for lesion detection was 2.0 ng/ml. On multivariate analysis prostate specific antigen at positron emission tomography (HR 1.37, p = 0.04) and clinical stage at initial diagnosis of prostate cancer (HR 5.19, p = 0.0035) were significant predictors of positive ¹¹C-choline positron emission tomography/computerized tomography. Conclusions: ¹¹C-choline positron emission tomography/computerized tomography performs well in men with biochemical recurrence after primary treatment failure. The optimal prostate specific antigen value for lesion detection is approximately 2.0 ng/ml. We found that ¹¹C-choline positron emission tomography/computerized tomography substantially enhances the rate of prostate cancer lesion detection by approximately 32% beyond what can be garnered using conventional imaging techniques and at a lower prostate specific antigen value.