MRI-guided core biopsy of the prostate in the supine position--introduction of a simplified technique using large-bore magnet systems.

OBJECTIVES: To introduce a simplified technique for MRI-guided core biopsies (MRGB) of the prostate in the supine position using large-bore magnet systems. METHODS: Fifty men with a history of negative transrectal ultrasound-guided biopsies underwent MRGB in either a 1.5-T (13/50) or 3.0-T (37/50) wide-bore MRI unit. MRGBs were conducted with the patients in a supine position using a dedicated MR-compatible biopsy device. RESULTS: We developed a dedicated positioning device for the supine position. Using this device, the biopsies were performed successfully in all patients. Apart from minor rectal bleeding, only one patient developed a major side effect (urosepsis). Histology revealed prostate cancer in 25/50 (50 %) patients. CONCLUSIONS: The new technique appears feasible. Its major advantage is the more comfortable and patient-friendly supine position during the biopsy without the need to modify the MRI system's patient table. KEY POINTS: • A novel positioning device for MRI-guided prostate biopsies has been developed. • Biopsies can be performed in the patient-friendly supine position. • The positioning device can be utilised without modifying the MRI's patient table.

Magnetic resonance image-guided biopsies with a high detection rate of prostate cancer.

AIM: To explore the potential of transrectal magnetic resonance image- (MRI-) guided biopsies of the prostate in a patient cohort with prior negative ultrasound guided biopsies. PATIENTS AND METHODS: Ninety-six men with suspected prostate cancer underwent MRI-guided prostate biopsies under real-time imaging control in supine position. RESULTS: Adenocarcinoma of the prostate was detected in 39 of 96 patients. For individual core biopsies, MRI yielded a sensitivity of 93.0% and a specificity of 94.4%. When stratifying patients according to the free-to-total prostate-specific antigen (PSA) ratio, the prostate cancer discovery rate was significantly higher in the group with ratios less than 0.15 (57.1%). CONCLUSION: MRI-guided biopsy of the prostate is a diagnostic option for patients with suspected prostate cancer and a history of repeatedly negative transrectal ultrasound-guided biopsies. Combined with the free-to-total PSA ratio, it is a highly effective method for detecting prostate cancer.

Prostate cancer in PI-RADS scores 1 and 2 version 2.1: a comparison to previous PI-RADS versions.

PURPOSE: To evaluate the validity of PI-RADS categories 1 and 2 version 2.1 (V2.1) as predictors of the absence of carcinoma and to reevaluate lesions that were analysed as suspicious prior to PI-RADS or according to PI-RADS versions 1 and 2 and classified as PI-RADS 1 or 2 in V2.1. METHODS: Retrospective evaluation of 1170 multiparametric MRIs performed at one academic teaching hospital (2012-2019). Study cohort comprised 188 men that achieved PI-RADS scores 1 or 2 (V2.1) and underwent systematic and targeted biopsy, split into one group with suspect findings in the original reports that were created prior to PI-RADS or with version 1 and 2, and another group with unremarkable reports. Differences in presence of prostate cancer and PSA density were assessed by Chi-square and Fisher's exact test, and the negative predictive value (NPV) for both groups was conducted. RESULTS: The NPV for clinically significant carcinoma (csCa) was 89.1% for 55 men with suspect findings in the original report and 93.2% for 133 men with negative MRI. There was no difference between the groups regarding the detection of csCa (p = 0.103). PSA density was significantly higher in the group with suspect original reports (p = 0.015). CONCLUSION: A PI-RADS score 1 or 2 appears less likely to miss existing prostate cancer, although a small amount of csCa can be overlooked. In case of clinical suspicion or elevated PSA density and PI-RADS score 1 or 2, an individual decision has to be taken if biopsy is necessary or if monitoring is sufficient.

MRI spectroscopy in screening of prostate cancer.

BACKGROUND: The purpose of this study was to evaluate the suitability of MR Spectroscopy in screening for prostate cancer in comparison to T2-weighted MR imaging. MATERIALS AND METHODS: Forty-six patients with biopsy confirmed prostate cancer underwent combined endorectal-body-phased-array MRI at 1.5T (Tesla). Twelve patients were additionally examined with 3D-spectroscopy sequence. The results of the spectroscopy were compared with the findings of T2-weighted MR imaging and the histological examination of radical prostatectomy specimens. RESULTS: With 3D-spectroscopy, a choline+creatine/citrate-ratio of 0.45 for healthy tissue and a ratio of 1.90 for tumor tissue were found and a significant difference between the groups was demonstrated. In 6 cases diagnosis of tumor localization was improved with spectroscopy in comparison with T2-weighted imaging alone. CONCLUSION: 3D-spectroscopy is a suitable technique for improving MR imaging of prostate cancer. This method can improve the diagnostic accuracy of T2-weighted imaging alone. At present, 3D-CSI spectroscopy alone can not be recommended with sufficient validity.

Impact of magnetic resonance imaging-guided prostate biopsy in the supine position on the detection of significant prostate cancer in an inhomogeneous patient cohort.

OBJECTIVE: The aim of this study was to determine the tumour detection rate of magnetic resonance-guided biopsy (MRGB) in the supine position for significant prostate cancer in an inhomogeneous patient cohort. MATERIALS AND METHODS: Thirty-two consecutive patients with a total prostate-specific antigen > 4 ng/ml and/or a tumour-suspicious palpable lesion upon digital rectal examination and a cancer-suspicious region in multiparametric magnetic resonance imaging (MRI) underwent MRGB in a standard 1.5 T magnet. Diagnostic MRI was performed in 20 patients at the authors' institute and 12 men at another location. Eight patients were investigated at 3 T and 24 at 1.5 T. Twenty men had prior negative biopsies and 12 were biopsy naïve. All biopsies were performed in the supine position using a table-mounted device and an 18 G biopsy gun. RESULTS: The overall tumour detection rate was 53% (17/32). Two cores (median; range 1-4) were extracted. Clinically significant cancers were found in 94% (16/17). None of the patients showed any postbiopsy complications. The prostate volumes of patients with cancer were significantly lower (39.3 ml) than those of men without cancer (49.7 ml). No significant differences were found between the numbers of tumour-positive and tumour-negative collected cores. In a median follow-up of 14 months, no cancer was detected in the negative biopsy group. CONCLUSION: MRGB in the supine position can be a valuable tool to detect significant prostate cancer, even in a patient cohort with different prebiopsy pathways. The biopsy method could be a reasonable alternative to MRGB in the prone position.

The Value of Endorectal Magnetic Resonance Imaging of the Prostate in Improving the Detection of Anterior Prostate Cancer.

BACKGROUND/AIM: The diagnosis of anterior prostate cancer (APC) is troublesome due to its anatomical location. Patients with an APC often require multiple sets of biopsies until diagnosis is made. The objective of this study is to examine if endorectal magnetic resonance imaging (e-MRI) of the prostate could improve the detection of APC. PATIENTS AND METHODS: A retrospective review of 412 patients records with a clinical suspicion of prostate cancer (PCa) (prostate-specific antigen (PSA) levels >4 ng/ml or a suspicious finding on digital rectal examination (DRE)) who underwent conventional e-MRI (e-cMRI) and functional e-MRI (e-fMRI) of the prostate and subsequent prostate biopsy from April 2004 to July 2010 was conducted. All patients had a history of at least one prior negative set of prostate biopsy. Sixty-five percent (N=268) of patients' images were considered suspicious for PCa of which 53 (12.8%) cases were considered to be suspicious for APC (defined as the presence of PCa anterior to the urethra). All patients underwent an 18-core transrectal ultrasonography (TRUS)-guided biopsy of the peripheral zone and an additional 3-core TRUS-targeted biopsy anterior to the urethra. RESULTS: The median age and median PSA levels of the patients was 68.9 (range=56-72) years and 12.7 ng/ml (range=6.4-21.3), respectively. DRE was only positive in 6 patients (11.4%). The overall PCa detection rate was 90.5%. APC was detected through the targeted cores in 48 patients (90.5%). Seven patients (13.2%) exhibited a PCa of the peripheral zone as well. e-MRI-positive predictive value was 90.5%. CONCLUSION: e-MRI of the prostate has a high predictive value in detecting APC. Patients with a constant increase of PSA levels, negative DRE findings and prior negative sets of prostate biopsy are ideal candidates for e-MRI of the prostate and subsequent TRUS-targeted biopsies of possible suspicious anterior gland sites.

How good is post-biopsy multiparametric magnetic resonance imaging in detecting and characterising the index lesion of localised prostate cancer?

OBJECTIVE: The aim of this study was to evaluate the accuracy of multiparametric endorectal magnetic resonance imaging (mp-MRI) in detecting and characterising the largest tumour lesion, which is defined as the index tumour of prostate cancer. MATERIAL AND METHODS: A total of 55 patients with proven histological prostate cancer underwent post-biopsy MRI at 1.5 T and subsequent radical prostatectomy. The maximum tumour diameter (MTD) of the index lesion was determined independently by MRI and histopathology in a prospective manner. The detection rate of the index lesion, the MTD and volume by pathology, and the pathological tumour (pT) stage were correlated with the MTD by MRI using Pearson's correlation. RESULTS: Pathohistology revealed 158 cancer foci. MRI detected 55 foci. The sensitivity, specificity, accuracy, and negative and positive predictive values of mp-MRI for index lesion detection were 89%, 100%, 90%, 44% and 100%, respectively. Three positive correlations were found: one between the MTD of the index lesion by MRI and the MTD by pathology (Pearson coefficient = 0.890, p < 0.01), a second between the MTD by MRI and the index tumour volume at pathology (Pearson coefficient = 0.786, p < 0.01), and a third between the MTD and the pT stage (Pearson coefficient = 0.678, p < 0.01). CONCLUSION: mp-MRI can accurately detect the index lesion and estimate the TVP of localised prostate cancer.

Inapparent tumor on endorectal multimodality magnetic resonance imaging of prostate: should we perform a biopsy?

OBJECTIVES: To examine whether one could spare patients with a clinical suspicion of prostate cancer (PCa) but inapparent tumor on multimodality endorectal magnetic resonance imaging (e-MRI) of the prostate from undergoing prostate biopsy. METHODS: A total of 109 patients with a clinical suspicion of PCa underwent conventional and functional e-MRI of the prostate and subsequently prostate biopsy. The inclusion criteria were prostate-specific antigen level>4 ng/mL or a suspicious finding on digital rectal examination. The images were interpreted by a highly experienced radiologist and were considered negative for PCa in all cases. Regardless of the negative findings, all patients underwent an 18-core prostate biopsy. Functional e-MRI included contrast-enhanced e-MRI and diffusion-weighted imaging. The examinations were performed on a closed 1.0-T system combined with an endorectal body phased-array coil. The clinicopathologic parameters of the patients included age, prostate-specific antigen level, digital rectal examination findings, PCa detection rate, clinically significant PCa detection rate, high-grade PCa detection rate, and e-MRI specificity. RESULTS: The median age of the patients was 67.4 years, and the median prostate-specific antigen level was 12.9 ng/mL. The digital rectal examination findings were positive in 42 patients (38.5%) and negative in 67 patients (61.5%). Overall, PCa was detected in 19.2% of patients, with 47.6% cases defined as clinically significant and 38.1% as high grade. Overall, the e-MRI specificity was 80.8%. CONCLUSIONS: The results of our study have shown that the absence of tumor on e-MRI scans of patients with a clinical suspicion of PCa does not rule out the probability of clinically significant and high-grade PCa, making prostate biopsy mandatory for these patients as well.

Guided e-MRI prostate biopsy can solve the discordance between Gleason score biopsy and radical prostatectomy pathology.

INTRODUCTION: The aim of this study is to examine if guided prostate biopsies based on abnormalities detected by conventional and functional endorectal magnetic resonance imaging (MRI) yield a more reliable representation of the radical prostatectomy pathology and to identify probable preoperative clinical variables that stratified patients likely to harbor significant upgrading. PATIENTS AND METHODS: From April 2004 to April 2009, a review of N=70 patients records diagnosed with prostate cancer by a 3-6 core guided transrectal ultrasound (TRUS) prostate biopsy based on abnormalities detected by conventional and functional endorectal MRI and who subsequently underwent radical prostatectomy and exhibited a significant upgrading was conducted. Additionally, a multivariate analysis with a significant upgrading as the outcome was performed including the following parameters: prostate specific antigen (PSA) level, clinical stage, prostate size and duration from biopsy to radical prostatectomy. RESULTS: A significant upgrading was noted in only 8.5% of patients, with 1.4% exhibiting a significant downgrading and the rest 90.1% exhibiting an exact Gleason score match. No preoperative clinical variables that stratified patients likely to harbour significant upgrading were identified. CONCLUSIONS: This type of biopsy method seems to solve the discordance between the biopsy Gleason score and radical prostatectomy pathology regardless of known preoperative clinical variables that can affect it.

The role of conventional and functional endorectal magnetic resonance imaging in the decision of whether to preserve or resect the neurovascular bundles during radical retropubic prostatectomy.

OBJECTIVE: Because the recovery of erectile function and the avoidance of positive surgical margins are important but competing outcomes, the decision whether to preserve or resect a neurovascular bundle (NVB) during radical prostatectomy (RP) is based on information concerning mostly the presence and location of extracapsular extension (ECE). Conventional endorectal magnetic resonance imaging (e-ctMRI) and functional endorectal MRI (e-ftMRI) of the prostate provide an excellent depiction of the pelvic and prostate anatomy, and are also useful in predicting the presence of prostate cancer as well as ECE, seminal vesicle invasion (SVI) and NVB involvement. Their predictive qualities, however, have shown significant interobserver variability. The aims of this study are to report on accuracy using e-ctMRI and e-ftMRI, and to assess their value in making the decision whether to preserve or resect the NVBs during RP. MATERIAL AND METHODS: From 2004 to 2007, 75 consecutive patients with a biopsy-proven prostate cancer and satisfactory erectile function, who were scheduled to undergo RP, were subjected to e-ctMRI and e-ftMRI before surgery. Interpretation was performed by a highly experienced radiologist blinded to patient clinical data. All patients underwent RP and a nerve-sparing (NS) procedure was considered appropriate if the tumour did not extend outside the capsule in the posterolateral region of the prostate as assessed by the images. RESULTS: An NSRP was performed in 78.7% of patients. Based on the e-ctMRI and e-ftMRI findings, the operative strategy was changed in 44% of patients. The findings favoured NVB preservation in 67% of patients with a high clinical probability of ECE, and opposed NVB preservation in 33% of patients with a low clinical probability of ECE. Based on the final histopathological findings, the surgical plan was successfully changed in all patients. The sensitivity, specificity and accuracy rate were 92%, 100% and 100% for ECE, SVI and NVB involvement, respectively, results which are higher than all other published international standards in this matter. CONCLUSIONS: e-ctMRI and e-ftMRI comprise a sufficient modality in detecting prostate cancer, ECE, SVI and NVB involvement. This technique seems to one of the most sensitive preoperative clinical staging methods for selective patients, and extremely useful for identifying candidates for an NSRP.