Metastatic prostate cancer: initial findings of PET with 2-deoxy-2-[F-18]fluoro-D-glucose.

Abstract
To evaluate the accuracy of positron emission tomography (PET) with 2-deoxy-2-[fluorine-18] fluoro-D-glucose (FDG) in the detection of osseous and soft-tissue metastases of prostate cancer. Thirty-four patients (mean age, 71 years) with biopsy-proved prostate cancer and known or suspected metastatic disease were examined. Blinded interpretation of the PET images was compared with bone scan, CT, and clinical follow-up findings. In 202 untreated osseous metastases in 22 patients, the sensitivity of FDG PET was 65% (131 of 202 metastases), with a positive predictive value of 98% (131 of 133 positive findings). The estimated standardized uptake value in metastases was 2.1-5.7. Soft-tissue metastases to the lymph nodes or liver were identified, but evaluation of pelvic lymph node metastases was severely limited because of bladder tracer activity. FDG PET can help identify osseous and soft-tissue metastases of prostate cancer with a high positive predictive value but is less sensitive than bone scintigraphy in the identification of osseous metastases.