Background Patients with negative TRUS biopsies yet persistently rising PSA values are at risk for occult but significant prostate cancers. The ability of multiparametric MRI and ultrasound (MRI/US) fusion biopsy to detect these occult prostate lesions may make it an effective tool in this challenging scenario. Methods Men with one or more negative systematic prostate biopsies participated in this trial. Between March 2007 and November 2011 all men underwent prostate 3T endorectal coil MRI and MRI/US fusion biopsy. In addition, all patients underwent standard 12 core TRUS biopsy in addition to targeted MRI/US fusion biopsy of concerning lesions identified on MRI. Results Of the 195 men with previous negative biopsies, 73 (37%) were found to have cancer using the MRI/US fusion platform combined with 12 core TRUS biopsy. High grade cancer (Gleason sum 8+) was discovered in 21 men (11%). All 21 men with high grade disease (100%) were detected with MRI/US fusion targeted biopsy while standard TRUS biopsy missed 12 of these high grade cancers (55%). Upgrading occurred in 28 men (38.9%) as a result of MRI targeting versus standard TRUS biopsy. The diagnostic yield of MRI with guided biopsy was unrelated to the number of previous negative biopsies, and persisted despite increasing number of previous biopsy sessions. On multivariable analysis, only PSAD and MRI suspicion level remained significant predictors of cancer. Conclusion Multiparametric MRI in conjunction with a MRI/US fusion biopsy platform is a novel diagnostic tool for detecting prostate cancer and may be ideally suited for patients with negative TRUS biopsies in the face of a persistent clinical suspicion for cancer.

Background Prostate cancer is currently diagnosed by random biopsies resulting in the discovery of multiple low risk cancers that often lead to overtreatment. Multiparametric magnetic resonance imaging (mpMRI) may have the potential to identify patients at low risk for cancer, thus obviating the need for biopsy. Methods We reviewed 800 consecutive patients who underwent a 3 Tesla mpMRI of the prostate with endorectal coil from March 2007 to November 2011. Two radiologists independently reviewed all suspicious lesions using T2-weighted, diffusion weighted, spectroscopic, and dynamic contrast enhanced MRI sequences. Patients with only low suspicion lesions (maximum of two positive parameters on mpMRI) who subsequently underwent TRUS/MRI-fusion targeted biopsy were selected for analysis. Results One hundred and twenty-five patients with only low suspicion prostatic lesions on mpMRI were identified. On TRUS/MRI-fusion biopsy, 77 of these patients (62%) had no cancer detected, 38 patients had Gleason 6 disease, and 10 patients had Gleason 7 (3+4) disease. Thirty patients with cancer detected on biopsy qualified for active surveillance using 2011 NCCN guidelines. No cases of high risk (≥ Gleason 4+3) cancer were identified on biopsy and of the fifteen patients that underwent radical prostatectomy at our institution, none were pathologically upgraded to high risk cancer. Thus, for patients with only low suspicion lesions, 88% (107 patients) either had no cancer or clinically insignificant disease. Conclusion Our results demonstrate that low suspicion lesions on mpMRI are associated with either negative biopsies or low grade tumors suitable for active surveillance. Such patients have a low risk of harboring high risk prostate cancers.

Purpose Anteriorly located prostate cancer (PCa) is traditionally under-diagnosed using transrectal ultrasound (TRUS)-guided biopsy, although it represents a significant proportion of all PCa. We describe the detection rate of these tumors with the addition of MR/US fusion-guided biopsy (FGB) to standard TRUS-guided biopsy. Materials and Methods All patients regardless of their prior biopsy history who were referred for clinical suspicion of PCa (i.e elevated PSA and abnormal DRE) underwent 3T multiparametric-MRI (MP-MRI) screening; and those with suspicious lesions in the anterior region of the prostate were identified. Patients then received a FGB of all suspicious lesions in addition to systematic 12-core extended sextant TRUS-guided biopsy. We conducted a lesion based analysis comparing cancer detection rates of anterior targets using FGB versus systematic cores taken from the same anatomic sextant within the prostate. Lengths of cancer in the most involved core were also compared between the two biopsy techniques employed. Patients with only anterior targets were analyzed separately. Results Of 499 patients undergoing FGB, 162 patients had a total of 241 anterior lesions. Mean age, PSA, and prostate volume in this group was 62 years, 12.7ng/dl, and 57mL, respectively. In total, PCa was diagnosed in 121 (50.2%) of anterior lesions identified on MP-MRI. Sixty-two (25.7%) of these anterior lesions were documented positive for cancer on systematic 12-core TRUS-guided biopsy cores, while 97 (40.2%) were positive on the targeted FGB cores (p=0.001). In lesions that were positive on both FGB and TRUS biopsy, the most involved core was 112% longer on FGB (3.7mm vs. 1.6mm, p≤0.01). Forty-two patients had only anterior lesions on MP-MRI; twenty-four of them (57.1%) were found to have cancer on the FGB + TRUS biopsy platform. Six patients were positive on FGB only. Thirteen were positive on both modalities. However, 7 of 13 were upgraded by to a higher Gleason score by FGB. All 5 patients positive on TRUS biopsy only were active surveillance candidates. Conclusion FGB detects significantly more anteriorly located PCa than TRUS-guided biopsy alone and may serve to be an effective tool for this subset of patients.

What ' s known on the subject? and What does the study add? MRI has been shown to improve prostate cancer detection rates. Pinto et al . ( J Urol 2011; 86: 1281 -5) reported their outcomes on 101 patients with low, moderate or high suspicion lesions on multiparametric MRI that were subsequently targeted via an MRI/ ultrasound fusion biopsy platform. The prostate cancer detection rates were 27%, 66% and 89% respectively. Sciarra et al . ( Clin Cancer Res 2010; 16: 1875 -83) performed a prospective trial in 180 patients with prior negative biopsy and persistent PSA elevation. Patients were randomized to either MRI targeted biopsy followed by random 12-core TRUS biopsy vs random TRUS guided biopsy alone. Prostate cancer detection in the MRI targeted group was 45.5% vs 24.4% in the random group.Although MRI has been shown to improve prostate cancer detection rates, there has not previously been any work looking at the ability of MRI to detect prostate cancer localized to the very distal apex of the prostate. This is an important topic in that it might lead clinicians to counsel their patients in treatment decisions if it is felt that a treatment might not treat this section of the prostate well, e.g. high intensity focused ultrasound therapy that might spare the distal apex. OBJECTIVE• To describe an undescribed ' very distal ' apical prostate cancer on multiparametric MRI (mpMRI) since apical prostate cancer can be diffi cult to detect in transrectal ultrasound guided biopsy and might therefore be missed in treatment decisions such as high intensity focused ultrasound or surgical therapy. PATIENTS AND METHODS• From January 2011 to December 2012 a total of 210 consecutive patients underwent 3 T mpMRI with endorectal coil followed by our previously described MRI/ ultrasound image fused and directed TRUS biopsies.• Patients also underwent 12-core TRUS sextant biopsies.• The inclusion criteria required at least one distal apical prostate lesion visualized on mpMRI and targeted for biopsy. RESULTS• A total of 38 men (median age 62 years, median PSA 7.68 ng/dL) were identifi ed as having distal apical prostate cancer on mpMRI.• Thirteen patients (34%) had a prior diagnosis of cancer and were on active surveillance protocols while 25 (66%) did not. Of those patients, 21 (55%) had undergone a median of two prior negative biopsies.• Twenty-two patients (58%) were positive on biopsy for prostate cancer. On breakdown of patients who were positive, 17 (77%) were positive on TRUS random biopsies and 21 (95%) were positive on MRI targeted biopsies with the majority of patients having multifocal disease.• At the distal apical lesions of interest, 80% were positive on MRI targeted biopsy. In addition 33% of these patients were upgraded based on MRI targeted biopsy at the distal lesion. CONCLUSIONS• Very distal apical prostate cancer can be accurately detected and sampled with mpMRI and subsequent MRI/ultrasound fusion biopsy.• This may aid clinicians and patients in decision making for therapeutic modalities. KEYWORDSprostate ca...