Abstract
Some men are subjected to multiple repeated biopsies because of ongoing suspicion of prostate cancer, which might subject them to complications. The aim of the study was to determine the diagnostic accuracy of magnetic resonance imaging (MRI)/target fusion–guided biopsy in comparison with systematic biopsy in our low prevalence prostate cancer population, in terms of validity measure, case detection rate, and detection of clinically significant cancer.
This is a retrospective cohort study. All consecutive patients who met the inclusion criteria (all men with persistent high prostate-specific antigen levels >4 ng/ml and/or subnormal finding in direct rectal examination, with suspicious regions identified on prebiopsy MRI) were subjected to transrectal MRI/ultrasound fusion–guided biopsy.
A total of 165 cases met the inclusion criteria and were included in the study. The cancer detection rate (CDR) of target biopsy was significantly higher than that of standard biopsy (27.9% vs 14%, respectively), and 25 cases (52%) were missed by standard strategy and correctly classified by multiparametric MRI with targeted biopsy (MRI-TB). On the other hand, only 2 cases (4.3%) were misclassified by MRI-TB, and one of them was clinically significant. There was an exact agreement between the 2 strategies in 15 (31%) cases. Targeted biopsy diagnosed 41.5% more high-risk cancers vs systematic biopsy (41.6% vs 6.2%, P < .001). The difference between sensitivity, specificity, and negative predictive value of MRI-TG varies between 80% and 98%.
The CDR of prostate cancer in general and clinically significant cancer, in specific, is significantly higher with MRI-TG modality than with systematic modality. Yet, MRI-TG biopsy still misses some men with clinically significant prostate cancer. Hence, the addition of a 12-core biopsy is required to evade missing cases of clinically significant and insignificant cancer.