PET/CT Imaging Restages Prostate Cancer After Surgery
Imaging can detect [11C]choline uptake in patients with elevated PSA after prostate removal
FRIDAY, Aug. 27 (HealthDay News) -- Positron emission tomography/computerized tomography (PET/CT) to detect [11C]choline uptake appears to be useful for re-evaluating prostate cancer disease stage for men who have increasing prostate-specific antigen (PSA) levels after radical prostatectomy and no evidence of disease on conventional imaging, according to a study in the September issue of The Journal of Urology.
Giampiero Giovacchini, M.D., of the University of Milano-Bicocca in Italy, and colleagues studied 109 patients who had PSA levels above 0.2 ng/mL after radical prostatectomy, no lymph node disease at prostatectomy, no evidence of metastatic disease on conventional imaging, no androgen deprivation therapy, and no radiotherapy. The subjects underwent [11C]choline PET/CT to re-evaluate their prostate cancer disease stage.
The researchers found that the PSA counts in the group at time of imaging ranged from 0.22 to 16.76 ng/mL (median 0.81 ng/mL). Based on the PET/CT imaging, local recurrence was diagnosed in four patients (4 percent) and pelvic lymph node disease in eight patients (7 percent). Scans were positive in 5 percent of patients with PSA less than 1 ng/mL, 15 percent with PSA between 1 and 2 ng/mL, and 28 percent with PSA greater than 2 ng/mL.
"Positron emission tomography/computerized tomography detected increased [11C]choline uptake, suggesting recurrent disease in 11 percent of patients with prostate cancer, increasing PSA after radical prostatectomy, and no evidence of disease on conventional imaging. This modality may be useful to restage disease but it cannot be used to guide therapy," the authors write.