Comparison of re-biopsy with preceded MRI and re-biopsy without preceded MRI in patients with previous negative biopsy and persistently high PSA.

Abstract

To retrospectively compare re-biopsy with preceded magnetic resonance imaging (MRI) and re-biopsy without preceded MRI. Between January 2007 and May 2011, 669 patients (mean 64 years; range 38-91 years) underwent a re-biopsy because of previous negative biopsy (median 1; 1-5) and persistently high prostate-specific antigen (PSA 10.6 ng/ml; 2.5-997.1 ng/ml). 3T MRI using a phased-array coil was performed in 171 (MRI group) but not in 498 (non-MRI group) prior to re-biopsy. Transrectal ultrasound-guided biopsy was performed in both MRI and non-MRI groups. MRI and non-MRI groups were compared in terms of cancer detection rate [(number of cancer-proven patients/number of patients in MRI or non-MRI group) × 100] and positive core rate [(number of cancer-positive cores/number of cores in MRI or non-MRI group) × 100] using Fisher exact test. Odds ratio and 95% confidence interval were also obtained. Pathologic diagnosis of the biopsy was considered standard reference. Of 669 patients, 129 (19.3%) were diagnosed with adenocarcinoma. The cancer detection rates of MRI and non-MRI groups were 33.3% (57/171) and 14.5% (72/498), respectively (p < 0.001). The positive core rates of these groups were 9.2% (167/1 818) and 3.2% (179/5 631), respectively (p < 0.001). The odd ratios of cancer detection rate and positive core rate were 3.0 (95% confidence interval 2.0-4.4) and 3.1 (2.5-3.8), respectively. Re-biopsy with preceded MRI yields higher cancer detection rate and positive core rate than re-biopsy without preceded MRI. MRI should be considered prior to re-biopsy in patients with previous negative biopsy and persistently high PSA.