Free-hand transperineal multiparametric magnetic resonance imaging/transrectal ultrasound fusion-guided targeted biopsy for the diagnosis of prostate cancer: a prospective study

Objective To assess the value of free-hand transperineal multiparametric magnetic resonance imaging/transrectal ultrasound(mpMRI/TRUS) fusion-guided targeted biopsy(TB) for the diagnosis of prostate cancer(PCa). Methods Patients with elevated PSA level and/or an abnormal DRE finding were recruited prospectively between January 2015 and September 2016. Patients were classified to various scores from 2 to 5 according to prebiopsy mpMRI PI-RADS. Based on free-hand transperineal mpMRI/TRUS fusion-guiding, a 2-cores TB for each cancer-suspicious lesion were carried out and followed 12-cores systematic biopsy(SB) protocol. Pathological findings of biopsy and radical prostatectomy (RP) specimens were analyzed. Results A total of 397 patients were enrolled in this study. The median age of the patients was (68.2±7.4)years old, ranging 42-78 years. The median PSA level was (15.0±12.4)ng/ml, ranging 3.0-88.3 ng/ml. DRE showed abnormality in 28 patients(7.1%). The median prostate volume was (41.6±16.4)cm3, ranging 24.6-89.8 cm3. The PCa detection rate of TB was significantly increased compared with SB (44.8 % vs. 34.8%) (P=0.003), especially in clinically significant PCa (P<0.001) and intermediate/high-risk PCa (P=0.003), respectively. Of the all 588 mpMRI targeted lesions, 277 lesions were positive. A total of 105 index tumors were identified in RP specimens, the locations of TB-proven cancer showed 96.6% (85/88) in correspondence with the location of the index lesion in RP specimens. Conclusions Free-hand transperineal mpMRI/TRUS fusion-guided TB providing greater detection of intermediate-high risk PCa while limits over detection of low risk PCa. Moreover, TB can reliably predict the location of an index tumor. Key words: Magnetic resonance imaging; Prostate cancer; Fusion image; Biopsy; Risk stratification