Feasibility and preliminary experience of quantitative T2* mapping at 3.0 T for detection and assessment of aggressiveness of prostate cancer.

RATIONALE AND OBJECTIVES To assess the feasibility of quantitative T2* mapping at 3.0 T for prostate cancer detection and to investigate the use of T2* values to characterize tumor aggressiveness, with whole-mount step-section pathologic analysis as the reference standard. MATERIALS AND METHODS Prostate multiecho T2* was performed in 55 consecutive patients with prostate cancer using a multishot fast-field echo sequence at 3.0 T magnetic resonance imaging. T2* mapping was obtained by exponentially fitting the multiecho T2* images pixel by pixel with different echo times for each slice. Generalized estimating equations were used to test the T2* value difference between normal and malignant prostate regions and the association between T2* value and tumor Gleason scores. RESULTS The T2* values of the cancerous prostatic regions (mean: 42.51 ± 0.65 milliseconds) were significantly lower (P < .001) than those of the normal prostatic regions (mean: 74.87 ± 0.99 milliseconds). Adopting a threshold value of 59.27 milliseconds, T2* mapping resulted in 94.8% sensitivity and 77.3% specificity in the identification of prostate cancer. A lower mean T2* value was significantly associated with a higher tumor Gleason score (mean T2* values of 53.53, 43.75, 33.66, and 22.95 milliseconds were associated with Gleason score of 3 + 3, 3 + 4, 4 + 3, and ≥8, respectively P < .05). CONCLUSIONS From these preliminary data, quantitative T2* mapping seems to be a potential method in the characterization of prostate cancer. T2* mapping may provide additional quantitative information that significantly correlated with prostate cancer aggressiveness.