DETECTION OF BONY METASTASES OF ANDROGEN-INDEPENDENT PROSTATE-CANCER BY PET-FDG

Fourteen F-18 fluorodeoxyglucose (FDG) studies were carried out in 13 patients known to have bony metastases from carcinoma of the prostate. One patient was newly diagnosed. The remaining patients had various t ypes of therapy and were considered hormonally resistant. The average age was 67. All patients had extensive bony metastases shown on the co nventional Tc99m-MDP bone scans. Only about 18% of bony lesions appare nt on the conventional bone scans showed corresponding increase of FDG uptake. Anatomical correlation was performed by using co-registered i mages of SPECT and PET in the same area. The positive FDG uptake was n ot related to the duration of illness, level of PSA, previous therapy, and magnitude of disease involvement. It appears that only a small pe rcentage of bony metastases is associated with increased glycolysis. I t is possible that other metabolic processes are more important than g lycolysis for providing prostate cancer with a source of energy and nu trients.