By: Dan Sperling, MD

Magnetic resonance imaging (MRI) of the prostate has been steadily progressing from basic or conventional MRI to an accurate and detailed technology due to the integration of functional parameters. A functional parameter refers to an imaging feature that preferentially distinguishes healthy prostate tissue from cancer by enhancing a specific characteristic (function) of cell behavior. Today, there are five parameters that can be used alone or in various combinations:

• T 1 weighted MRI (T1W MRI)
• T2 weighted MRI (T2W MRI)
• Diffusion Weighted Imaging (DWI-MRI)
• Contrast-enhanced MRI (CE-MRI)
• MRI Spectroscopy (MRI-S)

(Other articles at this site have explained one or more of these parameters in more detail, and interested readers are referred to them in the endnotes.[i])

Each of these parameters highlights a cellular property that can distinguish healthy tissue from tumor tissue. For instance, tumor cells have greater density, less elasticity, different metabolite composition, and more water molecule restriction than healthy cells. Any one of the parameters by itself may indicate a suspicious abnormality. As an example, much has been written about the accuracy of DWI-MRI which “reads” the hydrogen protons in water molecules and thus can reveal how restricted the water molecules’ motion is.

An article on this site, “Combining MRI Parameters is Better than T2 Weighting Alone,” reported a Memorial Sloan-Kettering study comparing the imaging capability of T2W MRI, DWI-MRI and DCE-MRI alone and in combination to detect PCa recurrence. They found combining T2W and DWI most effective. Click here for details:  https://sperlingprostatecenter.com/combining-mri-parameters-better-t2-weighting-alone/

Another study, this time out of a Chinese university medical center, used the same three parameters to detect prostate cancer in the central gland.[ii] (For a diagram of prostate zones see http://www.gfmer.ch/selected_images_v2/detail_list.php?cat1=13&cat2=87&cat3=0&cat4=11&stype=n ) The goal of the Chinese study was to use the best imaging approach to qualitatively diagnose central gland prostate cancer (CGPCa). The basis for their study was 42 patients with biopsy-proven CGPCa and 42 patients biopsy-proven benign prostate hyperplasia (BPH). All patients were followed up by imaging using T2W, DWI, and DCE MRI, first separately, and then all combined. The results are shown in this table:

The authors concluded, “DWI is better than T?WI for diagnosing CGPCa. Combining T?WI+DWI+DCE-MRI can obviously improve the diagnostic accuracy of CGPCa. And it has excellent consistency with pathological analysis.”

Today’s multiparametric MRI is unparalleled at detecting lesions suspicious for cancer. While it may seem obvious that the synergistic information obtained when two or more parameters work together would be more valuable than any given parameter alone, the importance of such studies as this lays in the evolution of imaging as a diagnostic tool. In today’s world, a needle biopsy is still the only way to examine prostate tissue for the presence of PCa cells, and to learn more about those cells at the molecular level. As functional parameters advance, and tests are done to combine information, the diagnostic world moves closer to a future in which cancer diagnosis can confidently be made by means of noninvasive imaging.

[i] The following articles on various prostate MRI imaging parameters may be of interest:

1. Dynamic Contrast Enhanced MRI Correlates With Prostatectomy Findings https://sperlingprostatecenter.com/dynamic-contrast-enhanced-mri-correlates-prostatectomy-findings/
2. MRI Imaging of Prostate Cancer: Two Parameters (DWI, DCE) https://sperlingprostatecenter.com/mri-imaging-prostate-cancer-two-parameters/
3. Detecting Prostate Cancer Distribution: Two Important MRI Parameters (DWI, MRI-S)

https://sperlingprostatecenter.com/detecting-prostate-cancer-distribution-two-important-mri-parameters/

[ii] Li P, Yang W, Chen Z et al. Preliminary study of combining T2-weighted imaging, diffusion weighted imaging and dynamic contrast enhanced-magnetic resonance imaging for diagnosing prostatic central gland cancer. Zhonghua Yi Xue Za Zhi. 2014 Aug 19;94(31):2448-51