Mri-based cancer lesion analysis with 3d printed patient specific prostate cutting guides

Am J Clin Exp Urol. 2019 Aug 15;7(4):215-222. eCollection 2019.

Abstract

Purpose: MRI methods have improved diagnosis and treatment planning for prostate cancer. However, validation and standardization is needed to encourage widespread adoption of these methods. The purpose of this study was to improve validation methods by creating a prostate cutting guide and to develop a method for 3D comparison between MRI data and post-prostatectomy histological tissue slices. Methods: Prostate Specific Membrane Antigen (PSMA) Positron Emission Tomography (PET)/MRI was performed on 10 patients with prostate cancer before and after chemohormonal treatment. Post-treatment images were used to design patient-specific prostate cutting guides that were used to create uniform thickness sections of surgically removed prostates. The thickness of the prostate tissue slices matched the imaging slice thickness so that comparisons could be made between MRI results and histopathological study results. A method was also developed to compare post-slicing prostate bulk geometry with the predicted MRI prostate geometry. Results: The prostate cutting guides were used to successfully section the prostate for histopathogical evaluation and slice-by-slice MRI comparison. Surface comparison results displayed an average dimensional difference of 1.99 ± 3.19 mm between MRI and post-prostatectomy slice reconstruction prostate geometries. Conclusion: MRI-based prostate cutting guides were designed, fabricated, and implemented in a study examining the utility and accuracy of MRI for the detection of prostate cancer. Furthermore, a three-dimensional part comparison method was developed, which can be used for validation of MRI with pathological and histological data. Future work will analyze more subjects to examine the effectiveness of these guides for histopathological prostate analysis with MRI and PET/MRI.

Keywords: 3D printing; Magnetic resonance imaging; prostate cancer; prostatectomy.