Session: PD39: Prostate Cancer: Detection & Screening V
PD39-09: Impact of Prostate Imaging Quality (PI-QUAL) score on the detection of clinically significant prostate cancer in men undergoing MRI-targeted biopsy
Introduction: The Prostate Imaging Reporting and Data System (PI-RADS) guidelines represented the first step towards the definition of an optimal scan protocol, providing minimal technical requirements for mpMRI acquisition. However, PI-RADS does not provide measures to evaluate the quality of mpMRI. The Prostate Imaging Quality (PI-QUAL) score represents a tool that could provide clinicians with practical information on MRI quality that can influence patient care. However, evidence on its clinical impact is still limited. We aimed at investigating the impact of PI-QUAL scores on the diagnostic performance of mpMRI in a targeted biopsy cohort. Methods: Overall, 200 consecutive patients who underwent both prostate mpMRI and subsequent biopsy at a single institution were included. All patients with at least one visible lesion at MRI (i.e. PI-RADS score =3) underwent MRI-targeted biopsies with concomitant standard 12-core random systematic biopsy (TRUS-Bx). PI-QUAL scores were retrospectively assigned by two radiologists in consensus and were correlated to pre-biopsy PI-RADS scores and biopsy outcomes. Inter-reader agreement on PI-QUAL scores was determined on a subset of one-hundred men using percentage of agreement (PA), Agreement Coefficients (AC1 and AC2) and k coefficients. Results: Median age was 67 years while the median PSA and PSA density was 6 ng/ml and 0.12 ng/ml2, respectively. The prevalence of any PCa at biopsy was 69% while the prevalence of csPCa was 46%. According to original MRI reports, 9% had a maximum score of PI-RADS 2, 31% had PI-RADS 3 and 60% had PI-RADS 4-5. Image quality was optimal (PI-QUAL =4) in 176/200 (88%) and suboptimal (PI-QUAL <4) in 24/200 (12%). The proportion of PI-RADS 3 scores referred for biopsy was higher in scans of suboptimal quality as compared to scans of optimal quality (42% vs 30%). In PI-QUAL <4 scans, the rate of false-positive findings of MRI was higher as compared to PI-QUAL =4 scans (58% vs 49%), as was the detection rate of targeted biopsies in PI-RADS =4 scans (50% vs 66%). Agreement on overall PI-QUAL scores was good (PA 83%; AC2 0.72; k = 0.24). Conclusions: Scan quality may affect the diagnostic performance of prostate mpMRI in men undergoing MRI-targeted biopsy. Scans of suboptimal quality (PI-QUAL <4) were associated with a higher proportion of false positive biopsy referrals, especially for PI-RADS =4 scans. SOURCE OF Funding: None
