Background: We evaluated the relationship between serum PSA and clinical variables to eliminate bone scanning in patients with prostate cancer having a low probability of bone metastasis.
Methods: The study included 366 patients with newly diagnosed prostate cancer between 1999 and 2005. Bone metastasis was studied for its correlation with various clinical and pathological variables in these patients.
Results: Bone metastasis was found in 28 (7.7%) of 366 patients. Fourteen patients had skeletal symptoms related to bone metastasis. The risk for bone metastases increased considerably with increases of PSA level, clinical T stage and Gleason score. The metastasis was not found in 161 patients with serum PSA concentration of 10 ng/ml or lower. In 95 patients with the concentration between 10 and 20 ng/ml only two had the metastasis. These two patients had T2 disease and Gleason scores of 7 or greater. In 204 patients with clinical stage T1 disease, one (0.5%) had the metastasis. In 117 patients with Gleason scores of 6 or less, the metastasis was found in two (1.7%).
Conclusions: For patients with serum PSA levels of 10 ng/ml or lower, bone scanning may be eliminated because of the negligible risk of bone metastases. In addition, scanning may not be necessary for those with PSA levels between 10 and 20 ng/ml, when they have T1 disease and Gleason scores of 6 or lower.