Aim: The optimal biopsy strategy for prostate cancer detection, especially in men with isolated prostate-specific antigen (PSA) elevation, remains to be defined. We evaluated diagnostic yield and safety of transrectal ultrasound (TRUS)-guided transperineal systematic 14-core biopsy and compared the spatial distribution of cancer foci detected with this technique in men with and without abnormality on digital rectal examination (DRE).
Methods: In a prospective study, 289 men aged between 50 and 87 years (median age, 70 years) underwent TRUS-guided transperineal systematic 14-core prostate biopsy because of elevated PSA and/or abnormal DRE findings. Using the fan technique, 12 cores from the peripheral zone and two cores from the transition zone were obtained systematically. To characterize the spatial distribution of cancer positive cores, site-specific overall and unique cancer detection rates were compared between stage T1c and T2 cancers.
Results: Prostate cancer was detected in 105 of the 289 patients (36%). Major complications requiring prolonged hospital stay or re-hospitalization during a 4-week postbiopsy period were rare (1.4%). Sixty-seven stage T1c cancers were identified. These cancers were associated with significantly lower PSA and a smaller number of cancer positive cores when compared with stage T2 cancers (n= 38). The overall cancer detection rate was highest at the anterior peripheral zone and the posterior peripheral zone in stage T1c and stage T2 cancers, respectively. The unique cancer detection rate at the anterior peripheral zone was significantly higher in stage T1c cancers than in stage T2 cancers. Therefore, when the prostate is extensively biopsied using the transperineal approach, cancer positive cores are characteristically distributed anteriorly in stage T1c cancers and posteriorly in stage T2 cancers.
Conclusions: TRUS-guided transperineal systematic 14-core biopsy showed an apico-anterior distribution of cancer foci in stage T1c prostate cancers.