576 for hemorrhage and prostatitis after the procedure. Furthermore, if the lesion is small, biopsy may not be per- formed accurately [4-6]. Regarding sampling errors, that is pointed out to be a limitation of prostate biopsy. It could be overcome to a certain degree by TRUS-guided biopsy; nonetheless, for intra-prostatic, tiny, focal prostate cancer lesions, it is not at a level comparable to the sensitivity of MRI. 　Magnetic resonance imaging is a useful method for diag- nosing prostate cancer and for determining disease stages. Particularly, it has been widely used to assess the location and border of tumors and the depth of infiltration to ad- jacent organs. Its sensitivity and specificity are con- tinuously being improved [30]. However, when MRI is per- formed after prostate biopsy, due to hemorrhages within tissues, it is difficult to determine the location of lesions, the range, and the cancer margin border, and thus the size of the lesion may be underestimated or overestimated [7-9]. But, as confirmed in our study, until now, the sensitivity of MRI that is performed before prostate biopsy is not great enough to replace prostate biopsy. 　Accuracy, low cost, reduced morbidity rate of other dis- eases or complications, and noninvasiveness are the best conditions for tumor diagnosis if possible. MRI is still an expensive diagnostic tool. However, it provides higher res- olution and contrast images of suspicious lesions with 3D reconstruction and it makes prostate biopsy more accu- rate, thus reducing the false-negative rate and morbidity rate. As observed in our study, MRI performed before pros- tate biopsy is anticipated to be of help in the diagnosis of prostate cancer and the determination of the area of biopsy. We suggest that additional studies on more patients are re- quired in the future. CONCLUSIONS The sensitivity, the positive predictive value, and the le- sion location match rate of MRI performed before prostate biopsy were lower than that of MRI performed after biopsy. Nonetheless, the possibility of the biopsy result influenc- ing the reading of the MRI cannot be ruled out. In compar- ison with other previous reports, our results suggest that the sensitivity of prostate cancer detection by MRI is on the rise. We thus conclude that MRI as a screening tool to diag- nose prostate cancer has become more useful. In addition, MRI before prostate biopsy can provide more information by which to identify prostate cancer during prostate biopsy, which is anticipated to be of help in reducing the false-neg- ative rate. 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