The clinical value of MR elastography in the diagnosis of prostate cancer / 中华放射学杂志

ABSTRACT

Objective To investigate the clinical value of MR elastography in the diagnosis of prostate cancer at 3.0 T, and to assess the elasticity and viscosity of prostate cancer and benign prostatic diseases. Methods Eight patients (63±7years old) with 12 foci of prostate cancer and 10 patients(59±3 years old) with 14 foci of prostatitis in the peripheral zone were evaluated by MR elastography.MR elastography was performed by transmitting low-frequency longitudinal mechanical waves of 100 Hz into prostate with a transducer placed above the pubic bones. The phase images were reconstructed to acquire viscoelastic mapping. T test was used to compare the mean elasticity and viscosity of prostate cancer and prostatitis. The correlation of elasticity and Gleason scores between prostate cancer and prostatitis were also retrospectively analyzed with Pearson Correlation. Results The mean elasticity and viscosity were significantly higher in prostate cancer[(6.55±0.47)kPa,(6.56±0.99)Pa·s,respectively]than in prostatitis[(1.99±0.66)kPa,(2.13±0.21)Pa·s,respectively],and the difference was statistically significant (t=19.392,16. 372; P ＜ 0.01). In 8 patients with prostate cancer, the Gleason scores were 5 (2 cases), 6 (3 cases), 7 (2 cases) and 8 (1 case), respectively. The mean elasticity for the cases with different Gleason scores was 5.83,6.02,7.45 and 8.05 kPa, respectively. There was a positive correlation between Gleason scores and elasticity of the prostate cancer( r = 0. 913, P ＜ 0. 01 ) in this study.Conclusion MR elastography can be used to visualize the difference in stiffness between prostate cancer and benign prostatic disease, it is a new imaging method with great potential in grading of prostate cancer.