Recent advances in MRI include: high field 3 Tesla machines for improved signal/contrast to noise ratios, multichannel RF transmission to improved field homogeneity, and digital multichannel RF receiving coils fur further SNR/CNR enhancement. MRI anatomic imaging provides high soft tissue contrast and special resolution. The protocol at Ohio State University includes both morphologic and parametric MRI: high resolution T1/T2 weighted signals, amide proton transfer, diffusion weighted imaging, dynamic contrast enhanced imaging, and diffusion weighted whole body imaging with background body signal suppression.
Imaging of neo-angiogenesis can exist at both the micro- and macro-circulation levels. Visual assessment of bladder cancer is improved with DCE-MRI to help localize malignant bladder tumors. This is augmented by color mapping. Microcirculation characteristics differ between clusters, implying various pharmokinetic parameters. Tumors of various stage may be identified with different cluster patterns. The following clinical step is to determine whether these cluster patterns predict treatment responders or non-responders.
Qualitative DWI requires no exogenous agent. The apparent diffusion coefficient (ADC) is estimated to quantify the water diffusibility in tissue microenvironments, with higher water diffusivity resulting in a higher ADC. At Ohio State, Dr. Knopp and colleagues quantify the special heterogeneity of ADC in tumor tissues at baseline and correlate the quantitative assessment of this with tumor response. This helps in differentiating malignant from benign lesions. In addition, these images can be augmented with next generation PET
We look forward to the rapidly advancing field of molecular imaging to have continued applications in bladder cancer and hope for it to permeate throughout all urologic malignancies.
Presented by: Michael V. Knopp, MD, PhD Vice Chair of Research, Professor, Novartis Chair of Imaging Research, Director, Wright Center of Innovation in Biomedical Imaging, Division of Imaging Science, Wexner Medical Center, Ohio State University
Written by: David B. Cahn, DO, MBS, @dbcahn, Fox Chase Cancer Center, Philadelphia, PA at the 18th Annual Meeting of the Society of Urologic Oncology, November 20-December 1, 2017 – Washington, DC