RSNA 2016

Abstract Archives of the RSNA, 2016


GU222-SD-TUA1

Volumetric Prostate Cancer Lesion Correlation on 3-Tesla Multiparametric MRI and Whole Mount Histopathology with Use of 3D-printed Custom-designed Molds

Tuesday, Nov. 29 12:15PM - 12:45PM Room: GU/UR Community, Learning Center Station #1



Awards
Student Travel Stipend Award

Pooria Khoshnoodi, MD, Los Angeles, CA (Presenter) Nothing to Disclose
Alan Priester, MS, Los Angeles, CA (Abstract Co-Author) Nothing to Disclose
Hector E. Alcala, MPH,PhD, Charlotteville, VA (Abstract Co-Author) Nothing to Disclose
Nazanin H. Asvadi, MD, Los Angeles, CA (Abstract Co-Author) Nothing to Disclose
Shyam Natarajan, Los Angeles, CA (Abstract Co-Author) Nothing to Disclose
Daniel J. Margolis, MD, Los Angeles, CA (Abstract Co-Author) Nothing to Disclose
Jiaoti Huang, Los Angeles, CA (Abstract Co-Author) Nothing to Disclose
Leonard S. Marks, MD, Los Angeles, CA (Abstract Co-Author) Speaker, Avero Diagnostics Investigator, Actavis, Inc Investigator, Indevus Pharmaceuticals Inc Investigator, Light Sciences Corporation Investigator, Hologic, Inc Investigator, Danaher Corporation Investigator, GlaxoSmithKline plc Investigator, Allergan, Inc Investigator, GTx, Inc Advisor, Indevus Pharmaceuticals Inc Advisor, Hologic, Inc Advisor, GlaxoSmithKline plc Advisor, GTx, Inc
Robert E. Reiter, MD, Los Angeles, CA (Abstract Co-Author) Nothing to Disclose
Steven S. Raman, MD, Santa Monica, CA (Abstract Co-Author) Nothing to Disclose
PURPOSE

To evaluate correlation of Prostate Cancer (CaP) tumor volume (TV) of regions of interest (ROI) on prostate multiparametric (MP) magnetic resonance imaging MRI (TVm)  with concordant foci TV on whole mount histopathology (WMHP) (TVh), and assess accuracy of MRI in estimating CaP TV stratified by Gleason score (GS) and  MP-MRI overall suspicion  assessment (OA).

METHOD AND MATERIALS

A HIPAA-compliant, IRB-approved study of 114 men who underwent 3T prostate MP-MRI before robotic radical prostatectomy from August 2013 to November 2015 was performed. Prostate and suspicious regions of interest (ROIs) were segmented on MRI and OA was determined using standardized criteria on a 1-5 scale. TVm was calculated by radiologist delineation of ROIs. A 3D patient-specific mold was printed to precisely fit the excised prostate based on MRI prostate segmentation. A pathologist contoured each tumor on all WMHP slides. Custom software automatically imported the annotated contoured WMHP slides, reconstructed the tumors in 3D, and calculated the TVh. A radiologist and pathologist reviewed each case to match each ROI to the concordant focus on WMHP. Pearson correlation coefficients (ρ) were calculated to determine strength of association between volumes of concordant lesion foci on MRI and WMHP.  Accuracy (A) of MRI in estimating CaP tumor volume (A=TVm/TVh) was calculated. Analyses were conducted using Stata 14.1. P-values<.05 were considered significant.

RESULTS

114 patients had 118 CaP foci (94 index tumors) on WMHP matched with MRI ROIs concordantly. Of 118 CaP foci GS was ≤6(3+3) in 26 (22%) , 7(3+4) in 59 (50%), ≥7(4+3) in 33 (28%). OA was 2 in 3 (3%), 3 in 37 (31%), 4 in 45 (38%), and 5 in 33 (28%). The median TVh and TVm were 1.12cc and 0.41cc respectively. The ρ between TVh and TVm was 0.55 overall (p<0.001), 0.27 in GS=6 (p=0.18), 0.52 in GS=3+4 (p<0.001) and 0.57 in GS≥4+3 (p<0.001) tumors. The ρ was 0.55,0.48 and 0.65 for tumors with OA of 3,4 and 5 respectively. The A was 0.28, 0.43 and 0.55 for OA 3,4 and 5 respectively (p<0.001).

CONCLUSION

On 3T MP-MRI, TVm has overall moderate correlation with TVh and true volume is consistently underestimated on MR. The best correlation is achieved for higher grade lesions and lesions with higher overall assessments. 

CLINICAL RELEVANCE/APPLICATION

3T MP-MRI consistently underestimates tumor size estimation, and its accuracy is important for targeted biopsy or focal therapy.