Anwar Roshanali Padhani MD, Presenter: Advisory Board, Acuitas Medical Ltd Advisory Board, Siemens AG Speakers Bureau, Siemens AG Researcher, Siemens AG Speakers Bureau, Johnson & Johnson

Giuseppe Petralia MD, Abstract Co-Author: Nothing to Disclose

Heminder Kaur Sokhi MRCS, FRCR, Abstract Co-Author: Nothing to Disclose

Francesco Sanguedolce PhD, MD, Abstract Co-Author: Nothing to Disclose

Nicola Anyamene, Abstract Co-Author: Nothing to Disclose

Giles Hellawell MD, MRCS, Abstract Co-Author: Nothing to Disclose

To investigate the ability of multiparametric MRI (mpMRI) to predict early treatment outcomes of Active Surveillance (AS) patients.

100 AS patients (cT1a-c; PSA≤10ng/ml; PSA density ≤0.2ng/ml/cc; Gs≤6; highest tumor volume in cores ≤50%) underwent 3 monthly PSA testing and repeat TRUS biopsy at 1 & 4 years. mpMRI (T2W, DWI, DCE &MRSI) was undertaken annually. The first mpMRI was evaluated by two independent radiologists (1&4 years experience), blinded to the 2yr outcome (continued/discontinued AS). mpMRI features including index lesion (IL) presence, location, size, type (diffuse/nodular), sequence PI-RADS score, ADC value, MRSI metabolic ratio, and DCE curve type were recorded. Overall Likert score for clinically significant disease and reader’s evaluation of suitability for AS were noted. Interobserver agreement, univariate and multivariate analysis and treatment free survival curves were calculated.  

Mean time on AS was 24.7 months; 44 withdrew from AS for PSA DT ≤2 years (11.4%), upgrading at repeat biopsy (11.4%), worsening mpMRI appearances (17.4%) and due to patient preference (2.3%). No differences were found between the continued/ discontinued AS groups for age, PSA, gland volume, PSA density. Interobserver agreement was moderate for DCE PI-RADS score (0.57) and substantial to almost perfect (0.63-97) for the remaining continuous/ordinal variables). A number of mpMRI features were significantly correlated to outcome on univariate analysis (both radiologists). Using logistic regression, significant variables were T2W PI-RADS score and ADC value for the more experienced radiologist, while stage, IL type, DCE PI-RADS score, overall Likert score and suitability assessment for the less experienced radiologist. mpMRI significantly improved outcomes prediction for the more experienced radiologist only (odds ratio 2.4). Survival curves showed clear separation for IL PI-RADS score, overall Likert score and suitability for AS for both observers (p<0.001).  

Baseline mpMRI can identify additional features that predict short term outcomes of AS.  

mpMRI has the potential to increase the precision of patient selection at initial triage for AS by helping to confirm suitability of patients by minimizing the inclusion of higher risk patients.  

Padhani, A, Petralia, G, Sokhi, H, Sanguedolce, F, Anyamene, N, Hellawell, G, Multiparametric MRI Predicts 2 Year Outcomes for Low Risk Prostate Cancer Patients on Active Surveillance  .  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014064.html