CAPABILITIES OF DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING TO EVALUATE THE EFFICIENCY OF TREATMENT FOR PROSTATE CANCER

Objective: to study the diagnostic capabilities of diffusionweighted magnetic resonance imaging (MRI) to evaluate the efficiency of treatment, the presence of progressive or recurrent prostate cancer (PC).

Material and methods. The results of small pelvic MRI in 44 patients who had medical (26 (59.1%) patients) or surgical (18 (40.9%) patients) treatment for PC were analyzed. Examinations were performed on a 1.5-Tesla superconducting MRI scanner with a multichannel phased array surface coil. Diffusion-weighted imaging (DWI) at b values of 1000 s/mm–2 was used in addition to the standard MRI protocol in all the cases. The measurable diffusion coefficient (MDC) was calculated when estimating DWI.

Results. Analysis of the results of DWI MRI has indicated that the criteria for the positive impact of medical treatment are a progressive decrease in the prostate volume, a reduction in a MRI signal of a tumor on isotropic DWI, and an increase in MDC. Progressive PC is suggested by a local increase in the MRI signal of a tumor on isotropic DWI and a low MDC. The study has establishes that after radical prostate vesiculectomy, the pattern of tissue masses at the site of cystourethral anastomosis should be assessed not earlier than 6 months postsurgery.

Conclusion. The performed studies have shown that DWI MRI is an objective technique to assess medical and surgical treatment for PC.

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