Abstract:
Objectives:
High-resolution prostate imaging may allow for detection of subtle changes in tumor size, decrease the reliance on biopsies, and help define tumor boundaries during ablation. This pilot clinical trial evaluates a novel high-resolution prostate MRI for detection of small, biopsy-proven prostate tumors.
Methods
Our team developed a software that can be loaded on any modern MRI to generate high resolution diffusion-weighted imaging sequences (HR-DWI), which were compared to standard diffusion-weighted imaging sequence (S-DWI) in a prospective pilot trial in active surveillance patients. HR-DWI captures the entire volume of the prostate rather than sections, reducing streaking artifacts and geometric distortions. Multiple shots, rather than single shots, are used to differentiate signal and noise, enhancing resolution. All images were read by two radiologists. The primary outcome was the percent of biopsy-proven zones seen in 17 patients. The trial was powered to detect discordant proportions of 0.04 and 0.40 at one-sided alpha = 0.05.
Results
The resolution was defined using standard phantoms. HR-DWI produced a 5-fold improvement in spatial resolution when compared to S-DWI. Multiparametric (MP)-MRI incorporating S-DWI was useful for predicting biopsy results (AUC 0.72, Fisher's exact p < 0.001); however, using HR-DWI allowed MP-MRI to be more highly predictive of biopsy results (AUC 0.88, Fisher's exact p < 0.001). AUC for MP-MRI incorporating HR-DWI was significantly larger than MP-MRI incorporating S-DWI (p = 0.002). MP-MRI with HR-DWI had a sensitivity of 95.7% and identified tumor in 22 of 23 zones proven to have cancer on biopsy. In contrast, MP-MRI with S-DWI had a sensitivity of 60.9% and only identified 14 of 23 biopsy-positive zones (p = 0.004).
Keywords:
MRI, Prostate cancer, Diffusion weighted imaging
Citation: Ali-Reza Sharif-Afshar, Christopher Nguyen, Tom S. Feng, Lucas Payor, Zhaoyang Fan, Rola Saouaf, Debiao Li, Hyung L. Kim Prospective Pilot Trial To Evaluate A High Resolution Diffusion-weighted MRI In Prostate Cancer Patients DOI: http://dx.doi.org/10.1016/j.ebiom.2016.03.041.
Published Online: April 14, 2016, Accepted: March 29, 2016, Received in revised form: March 28, 2016, Received: February 12, 2016
Copyright: © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Conclusion
We developed a novel DWI and evaluated its improved resolution in a clinical setting. This technology has many potential applications and should be evaluated in future clinical trials as a patient management tool.
Disclosure
All authors have no relevant financial or nonfinancial relationships to disclose.
Acknowledgements
The project described was supported by the Lauhlere Family Fund and the National Center for Advancing Translational Sciences, Grant UL1TR000124 and NIH Grant 1F31EB018152-01A1. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.
