Page 3 - The Contemporary Role of Conventional Imaging for Staging, Re-staging, and Monitoring Prostate Cancer: Impact on Management

Gleave and colleagues performed a retrospective scan. Indeed, false positives are not often considered
review of patients with newly diagnosed prostate when evaluating bone scan results, and a number
cancer to assess the relationship between serum of benign conditions can show increased tracer
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prostate-specific antigen (PSA) level and a positive uptake. Consequently, a false positive result could
bone scan. Only 6% of 490 evaluable patients had a lead to major changes in clinical management, thus
positive bone scan on initial evaluation and the authors inconclusive or suspicious bone lesions on bone scan
concluded that routine bone scan could be eliminated should be confirmed by another imaging modality (CT,
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in patients with PSA levels less than 10 ng/mL. In a MRI) or a bone biopsy.
similar study, the rate of positive scan was 1% (3/308)
in patients with Gleason score 2-7, PSA of 50 ng/mL Guidance for Imaging Use in Primary Staging
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or less, and clinical stage of T2b or less. A systematic
review of 23 studies examining the role of bone scan for Before Local Therapies
detecting metastasis showed that patients with newly
diagnosed, low-risk prostate cancer were unlikely to any of the leading urology or urology-oncology
have metastatic disease detected by bone scan or CT. 6 Massociations have provided recommendations for
optimal use of imaging procedures for primary staging
Despite a lack of strong reference standard for of prostate cancer (Table 2). In patients with newly
bone disease, the performance of various imaging diagnosed prostate cancer, imaging investigations
modalities for detection of early bone metastases in should be limited to men with unfavourable
prostate cancer was assessed in two meta-analyses: intermediate- and high-risk disease. In these cases,
conventional imaging was compared with highly conventional imaging such as bone scan, MRI, and
specific choline-PET/CT (Table 1). These data highlight CT are suggested modalities.
the relatively poor specificity of conventional bone

Table 1. Sensitivity and Specificity of Imaging Modalities for Detecting Early Bone Metastases

Eligible Pooled Per-Patient Sensitivity Pooled Per-Patient Specificity
Studies (N)

Tc-Bone Choline F-Fluoride Whole Tc-Bone Choline F-Fluoride MRI
Scan PET/CT PET/CT Body MRI Scan PET/CT PET/CT

Wondergem et al, 2013 8 13 Range 85.2% 86.9% – Range 96.5% 79.9% –
(39-100%) (57-80%)

Shen et al, 2014 9 27 79% 91% – 97% 82% 99% – 95%

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