Objective: To determine whether the level of prostate-specific antigen (PSA) can be used to decide which patients with newly diagnosed prostatic carcinoma require a staging bone scan.
Patients and methods: Of patients 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 determined within 4 weeks of the bone scan and were assessed retrospectively for the presence of bony metastases.
Results: Of the 98 patients, 26 who had bone scans showing bony metastases had a PSA level > 40 ng/mL. Reviewing the other published studies showed that in those newly diagnosed 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.