Diagnostic and cost-effectiveness of axial skeleton MRI in staging high-risk prostate cancer

Omar El-Taji; Hannah Evans; Vandan Arora; Suzanne Amin; Manal Kumar; Thiagarajan Nambi Rajan

doi:10.1002/bco2.210

Diagnostic and cost-effectiveness of axial skeleton MRI in staging high-risk prostate cancer

BJUI Compass. 2023 Jan 31;4(3):346-351. doi: 10.1002/bco2.210. eCollection 2023 May.

Authors

Omar El-Taji¹, Hannah Evans¹, Vandan Arora^{2

3}, Suzanne Amin², Manal Kumar¹, Thiagarajan Nambi Rajan¹

Affiliations

¹ Department of Urology Wirral University Teaching Hospitals Wirral UK.
² Department of Radiology Wirral University Teaching Hospitals Wirral UK.
³ School of Medicine University of Bolton Bolton United Kingdom.

Abstract

Introduction: Current literature suggests that axial skeleton magnetic resonance imaging (AS-MRI) is more sensitive than Tc 99m bone scintigraphy (BS) for detecting bone metastases (BM) in high-risk prostate cancer (PCa). However, BS is still widely performed. Its diagnostic accuracy has been studied; however, its feasibility and cost implications are yet to be examined.

Methods: We reviewed all patients with high risk PCa undergoing AS-MRI over a 5-year period. AS-MRI was performed on patients with histologically confirmed PCa and either PSA > 20 ng/ml, Gleason ≥8, or TNM Stage ≥T3 or N1 disease. All AS-MRI studies were obtained using a 1.5-T AchievaPhilips™MRI scanner. We compared the AS-MRI positivity and equivocal rate with that of BS. Data were analysed according to Gleason score, T-stage and PSA. Multivariate logistic regression analyses were used to quantify the strength of association between positive scans and clinical variables. Feasibility and burden of expenditure was also evaluated.

Results: Five hundred three patients with a median age of 72 and a mean PSA of 34.8 ng/ml were analysed. Eighty-eight patients (17.5%) were positive for BM on AS-MRI (mean PSA 99 [95% CI 69.1-129.9]). Comparatively 409 patients (81.3%) were negative for BM on AS-MRI (mean PSA 24.7 (95% CI [21.7-27.7]) (p = 0.007); 1.2% (n = 6) of patients had equivocal results (mean PSA 33.4 [95% CI 10.5-56.3]). There was no significant difference in age (p = 0.122) between this group and patients with a positive scan, but there was a significant difference in PSA (p = 0.028), T stage (p = 0.006) and Gleason score (p = 0.023). In comparison with BS, AS-MRI detection rate was equivalent or higher compared with the literature. Based on NHS tariff calculations, there would be a minimum cost saving of £8406.89. All patients underwent AS-MRI within 14 days.

Conclusion: The use of AS-MRI to stage BM in high-risk PCa is both feasible and results in a reduced burden of expenditure.

Keywords: bone metastasis; cost analysis; high‐risk; magnetic resonance imaging; prostate cancer.