Do all patients with newly diagnosed prostate cancer need staging radionuclide bone scan? A retrospective study

ABSTRACT

PURPOSE: Define a group of patients with newly diagnosed prostate cancer, whose risk of bone metastasis is low enough to omit a bone scan staging study. MATERIALS AND METHODS: From 2003 to 2009, the medical records of patients who were newly diagnosed with prostate cancer were retrospectively reviewed. The data collected included age, digital rectal examination, serum prostate specific antigen (PSA), Gleason score, clinical T stage, and bone isotope scan. Patients were divided into two groups according to the results of bone isotope scan; positive group and negative group. A univariate and multivariate binary logistic regression was used to analyze the results. RESULTS: Of the 106 patients, 98 had a complete data collection and were entered into the study. The median age of the patients was 70.5 years and patients with a positive bone scan was 74 years, significantly higher than for patients with negative scans (69 years) (p = 0.02). Bone metastasis was detected in 39 cases (39.7 percent). In all patients with clinical T1-2 stage, a Gleason score of < 8 and PSA = 20 ng/mL, the bone isotope scans were negative. In univariate analysis, PSA (> 20 ng/mL) and Gleason score (> 7) were independently predictive of positive bone scan, while clinical stage was not. CONCLUSION: Staging bone scans can be omitted in patients with a PSA level of = 20 ng/mL, and Gleason score < 8. Our results suggest that by considering the Gleason score and PSA, a larger proportion of patients with prostate cancer could avoid a staging bone scan.