Yield of bone scintigraphy for the detection of metastatic disease in treatment-naive prostate cancer: a systematic review and meta-analysis

Aim To evaluate the yield of staging bone scintigraphy in patients with treatment-naive prostate cancer. Materials and methods A computerised search of the MEDLINE and EMBASE databases was performed to find relevant original literature. Studies that investigated the positivity of a staging bone scintigraphy according to prostate-specific antigen (PSA) levels and/or Gleason score in patients with treatment-naive prostate cancer were eligible for inclusion. Meta-analytic pooling was performed using the inverse variance method for calculating weights. Results Fifty-four eligible studies, which included a total sample size of 20,421 patients, were included. The pooled proportions of the positive bone scintigraphy in patients with PSA ≤10, 10 <PSA ≤20, and PSA >20 were 3.5% (95% confidence interval [CI]: 2.4–5%), 6.9% (95% CI: 4.5–10.3%), and 41.8% (95% CI: 36.3–47.6%). The pooled proportions of the positive bone scintigraphy examinations in patients with Gleason score ≤6, 7, and ≥8 were 4.1% (95% CI: 2–8%), 10% (95% CI: 6.1–15.8%), and 28.7% (95% CI: 21.8–36.8%). Meta-regression analysis revealed that the Gleason score was a significant factor affecting study heterogeneity in patients with PSA ≤10 (p = 0.04). Pooled proportions of positive bone scintigraphy examinations showed 3.4% in patients with a PSA of ≤10 and 3.3% in patients with 10 <PSA ≤20 regarding a Gleason score of ≤7. Conclusion The present results demonstrate a low proportion of positive bone scintigraphy examinations in treatment-naïve prostate cancer patients with PSA≤20 and Gleason score ≤7. The present study may help guide decision support in daily clinical practice regarding the need for bone scintigraphy in this group of patients and might be considered in the design of future clinical guidelines.