The use of high resolution MRI of the prostate is an exciting new tool in the diagnosis of and treatment planning for prostate cancer. MRI of the prostate is NOT a screening tool for cancer of the prostate, but can help to direct prostate biopsy in those men with abnormal/rising PSA levels with negative prostate transrectal ultrasound (TRUS) biopsies by their urologist. The use of several different ways to look at the prostate gland with MRI is known as Multi-Parametric Prostate Imaging and includes typical anatomic imaging along with additional imaging techniques of Diffusion Weighted Imaging (DWI) and Dynamic Contrast Enhanced (DCE) imaging, the latter imaging after the intravenous injection of a MRI specific contrast material; there is rapid and frequent scanning of the prostate after the injection of this contrast, with “mapping” of the prostate gland, looking for areas typical of prostate malignancy, with rapid uptake and then release of contrast. There are likewise findings on DWI which are often, but not always, associated with these prostate cancers. By using both anatomic and somewhat functional imaging of the prostate, we can often demonstrate areas of tumor and then direct biopsy.
The same imaging, both of the gland and the entire pelvic region, can aid in staging the tumor, which then directs the type of treatment options available. MRI can readily show local extension of tumor outside the prostate covering, or capsule, as well as regional spread to the lymph nodes of the pelvis.
Following radiation or surgical therapy to the gland, when the PSA level is abnormally rising or there is clinical suspicion of tumor, these described MRI techniques can often identify new or recurrent areas of tumor.