Introduction and objective: We aimed to evaluate the detection rate of PCa and clinically significant PCa (csPCa) in consecutive cores taken in course of Magnetic Resonance/Ultrasound (MRI/US) Fusion prostate biopsy
Material and methods: We prospectively enrolled 99 consecutive patients with clinical suspicion of PCa or previously diagnosed with low risk PCa in active surveillance protocol. Each patient was found with one or more detectable Index lesions at 1.5T mpMRI (multiparametric MRI) with endorectal coil. MRI/US Fusion-biopsy was performed from January 2015 to March 2017. Six targeted cores were taken in each Index lesion. Firstly, we evaluated the overall PCa detection rate and furthermore the csPSa (namely, Gleason score ≥ 3+4) diagnosis in these patients. In a second step, we analyzed a subgroup of patients referred to both targeted and systematic biopsy (n=71). In these patients, the overall and csPCa detection after systematic biopsy or targeted biopsy alone or in combination was assessed. Finally, we analyzed the detection rate of overall PCa, clinically insignificant PCa and csPCa according to the consecutive number of targeted core taken (namely, 1, 1-2, 1-3, 1-4, 1-5, 1-6).
Results: Table 1 depicts overall patients characteristics. Overall, 31 (31.3%) patients were biopsy naïve, 52 (52.5%) underwent one or more previous negative systematic biopsy and 16 (16.2%) had biopsy proven low risk PCa in active surveillance protocol. The index lesions diagnosed at mpMRI were classified as PIRADS 3 and 4-5 in 39.4% and 60.6% of cases, respectively. Concomitant systematic biopsy was performed in 71 (71.7%) patients. The overall PCa and csPCa detection rates were 75.8% and 58.6%, respectively. Considering patients referred to both systematic and targeted biopsy, the systematic biopsy alone would have detected 62% and 26.8% of PCa and csPCa, respectively. Targeted biopsy added 18.3% more cases, including 12.7% of csPCa (Table 2). Figure 1 depicts PCa detections according to Gleason group in each targeted biopsy core taken (namely, from core 1 to core 6). PCa and csPCa detection increases each consecutive targeted sample taken: 40.4% and 29.3%, 52.6% and 38.4%, 57.6% and 45.5%, 61.6% and 48.5%, 63.4% and 50.5%, 64.6% and 52.2%, in core 1, 1-2, 1-3, 1-4, 1-5 and 1-6, respectively (Figure 2).
Conclusions: Our study demonstrate that the detection of csPCa increases within each number of consecutive samples taken.
