High Spatiotemporal Resolution Prostate MRI

Prostate cancer is, after lung cancer, the second leading cause of death by cancer in men. Approximately one in nine men in the United States will be diagnosed with prostate cancer in their lifetime. Thus, the prevalence of prostate cancer is very high. Also, once it diagnosed, the 5-year survival rate of men undergoing treatment for prostate cancer is very high, well over 90%. Thus, any means for improving the rate of accurate detection of prostate cancer would have major implications on men's health. Yet another aspect of prostate cancer is that the degree of aggressiveness is highly variable. Means for further characterizing if prostate cancer is non-aggressive could possibly spare men the unnecessary cost and potential side effects associated with major treatment. Similarly, if known cancer is determined to be aggressive, then this could quickly stimulate treatment.

The purpose of this project is to develop an improved method for using magnetic resonance imaging (MRI) for the detection and characterization of prostate cancer. Current MRI methods can portray the transit of contrast-enhanced blood through the prostate gland but with relatively coarse spatial detail and at a rate of one 3D image every 6 seconds. We will develop means for providing a factor of 10 improvement in this, allowing very high spatial detail images with frame times in the range of 2 to 3 seconds. This improvement will allow improved accuracy and precision in determining time-related parameters with fine spatial detail. We will provide this improvement by adapting methods we have previously developed in another application in the imaging of contrast-enhanced blood, namely for the imaging of blood vessels. These techniques are based on MRI physics and MRI engineering.

The types of patients that will benefit from this project are men who have elevated PSA (prostate specific antigen) levels. This MRI test will help determine if there is prostate cancer actually present, allowing direct visualization and localization within the prostate gland. That subgroup of men who have known prostate cancer will further benefit from this test in that the temporal parameters determined from the MRI test can help characterize the level of aggressiveness of the known cancer. An additional group of men who can benefit from the test are those individuals who have undergone major treatment for prostate cancer, such as radical prostatectomy. This test will help assess if there has been recurrence of the cancer.

The benefits of the results of this project are improved overall accuracy in the detection of prostate cancer and improved confidence in the characterization of the aggressiveness of such cancer if it is detected. The risks of those undergoing the new test are no different from those associated with MRI used with intravenous administration of contrast material. These are regarded as minimal risk.

Improvements resulting from this project are expected to occur in phases. The technical improvements in spatial detail and faster frame rate are the principal purposes of the project and will occur over the 3 years of the requested funding. The manifestation of this in individual patient studies is expected to also be seen in studies done on patients recruited for this project, also over the 3-year timeframe. The assessment of improved clinical outcomes will need to be done in a detailed clinical study, ideally performed across multiple institutions. This is beyond the scope of this project, but is expected to be completable within approximately 3 years after the completion of this project.