Objective To determine whether the level of prostate-specific antigen
(PSA) can be used to decide which patients with newly diagnosed prosta
tic carcinoma require a staging bone scan. Patients and methods Of pat
ients referred during an 18-month period for a staging bone scan, 98 (
median age 72 years, range 52-89) had had their serum PSA level determ
ined within 4 weeks of the bone scan and were assessed retrospectively
for the presence of bony metastases. Results Of the 98 patients, 26 w
ho had bone scans showing bony metastases had a PSA level >40 ng/mL. R
eviewing the other published studies showed that in those newly diagno
sed patients with a PSA level of <20 ng/mL, the probability of having
bony metastases detected on a bone scan was <1%. Conclusions A staging
bone scan can be omitted in the vast majority of patients with newly
diagnosed prostatic carcinoma and a PSA level <20 ng/mL.