The impact of health-policy-driven subsidisation of prostate magnetic resonance imaging on transperineal prostate biopsy practice and outcomes

Abstract

Background: From 1 July 2018, the Australian Medicare Benefits Schedule (MBS) introduced rebates for multi-parametric magnetic resonance imaging (mpMRI) for the workup for prostate cancer (PCa). We aimed to determine if subsidisation of mpMRI prior to transperineal biopsy altered our institution's prostate biopsy practice patterns and outcomes.

Methods: All patients who underwent transperineal prostate biopsy at an Australian tertiary institution from 1 January 2017 to 1 January 2020 were identified. Patients with known PCa were excluded. Patients were stratified into two groups: a pre-subsidisation cohort comprising patients biopsied prior to the introduction of mpMRI subsidisation on 1 July 2018 and a post-subsidisation cohort comprising patients biopsied after 1 July 2018. Histopathological results were compared with further stratification based on mpMRI results. Clinically significant cancer was defined as ISUP Grade Group ≥ 2.

Results: Six hundred and fifty men fulfilled the inclusion criteria. Three hundred and sixty-one patients were in the pre-subsidisation cohort and 289 in the post-subsidisation cohort. Of the patients in the pre-subsidisation group, 36.3% underwent a pre-biopsy mpMRI compared with 77.5% in the post-subsidisation group. Of the patients in the pre-subsidisation group, 59.6% had positive biopsies (p = 0.024) compared with 68.2% in the post-subsidisation group. The rate of clinically significant PCa was lower in the pre-subsidisation group (39.1%) compared with the post-subsidisation (49.5%, p = 0.008). The negative predictive value of mpMRI for clinically significant PCa was 86.5%.

Conclusion: Our institution experienced a reduction of negative prostate biopsies and an increase in clinically significant PCa within transperineal biopsy specimens after the Australian healthcare system introduced financial subsidisation of mpMRI.

Keywords: MRI; diagnosis; elevated PSA; prostate cancer; public health.