407 research outputs found
MRI-targeted or standard biopsy for prostate-cancer diagnosis
Background Multiparametric magnetic resonance imaging (MRI), with or without targeted biopsy, is an alternative to standard transrectal ultrasonography-guided biopsy for prostate-cancer detection in men with a raised prostate-specific antigen level who have not undergone biopsy. However, comparative evidence is limited. Methods In a multicenter, randomized, noninferiority trial, we assigned men with a clinical suspicion of prostate cancer who had not undergone biopsy previously to undergo MRI, with or without targeted biopsy, or standard transrectal ultrasonography-guided biopsy. Men in the MRI-targeted biopsy group underwent a targeted biopsy (without standard biopsy cores) if the MRI was suggestive of prostate cancer; men whose MRI results were not suggestive of prostate cancer were not offered biopsy. Standard biopsy was a 10-to-12-core, transrectal ultrasonography-guided biopsy. The primary outcome was the proportion of men who received a diagnosis of clinically significant cancer. Secondary outcomes included the proportion of men who received a diagnosis of clinically insignificant cancer. Results A total of 500 men underwent randomization. In the MRI-targeted biopsy group, 71 of 252 men (28%) had MRI results that were not suggestive of prostate cancer, so they did not undergo biopsy. Clinically significant cancer was detected in 95 men (38%) in the MRI-targeted biopsy group, as compared with 64 of 248 (26%) in the standard-biopsy group (adjusted difference, 12 percentage points; 95% confidence interval [CI], 4 to 20; P=0.005). MRI, with or without targeted biopsy, was noninferior to standard biopsy, and the 95% confidence interval indicated the superiority of this strategy over standard biopsy. Fewer men in the MRI-targeted biopsy group than in the standard-biopsy group received a diagnosis of clinically insignificant cancer (adjusted difference, -13 percentage points; 95% CI, -19 to -7; P<0.001). Conclusions The use of risk assessment with MRI before biopsy and MRI-targeted biopsy was superior to standard transrectal ultrasonography-guided biopsy in men at clinical risk for prostate cancer who had not undergone biopsy previously. (Funded by the National Institute for Health Research and the European Association of Urology Research Foundation; PRECISION ClinicalTrials.gov number, NCT02380027 .)
Effect of Level of Urology Training on Gleason Score and Prostate Volume Estimation Agreement between Transrectal Ultrasound Guided Biopsy and Radical Prostatectomy Specimen
Introduction Transrectal ultrasound guided prostate biopsy may be performed by operators with various levels of training. Little is known about the impact of training level on biopsy results. We evaluated the effect of training level on the accuracy of transrectal ultrasound guided prostate biopsy findings. Methods We retrospectively reviewed 500 consecutive patients who underwent transrectal ultrasound guided prostate biopsy and subsequent radical prostatectomy. Transrectal ultrasound operators were stratified based on level of training as junior, senior, chief, fellow or staff. Linear regression was performed to analyze the effect of training level on volume estimates. A weighted Kappa statistic evaluated agreement between biopsy and pathological Gleason scores while an adjusted cumulative logistic regression model analyzed the effects of training level. Results A total of 482 patients were included in the final analysis. Transrectal ultrasound guided biopsy was performed by staff in 78 (16%) patients, by fellows in 18 (4%), chief residents in 48 (10%), senior residents in 126 (26%) and junior residents in 212 (44%). There was no significant difference between transrectal ultrasound and radical prostatectomy specimen volume estimates among the training levels. Level of training was not significantly associated with pathological features, including Gleason score, primary Gleason grade, highest single Gleason grade and estimated tumor volume. Study limitations include the retrospective design and the variability among members of the same group. Conclusions Agreement between biopsy and pathological Gleason scores is high for all levels of training. Training level has no impact on prostate volume estimations or the prediction of pathological features
Predictors of prostate volume reduction following neoadjuvant cytoreductive androgen suppression
Purpose: Limited duration cytoreductive neoadjuvant hormonal therapy (NHT) is used prior to definitive radiotherapeutic management of prostate cancer to decrease prostate volume. The purpose of this study is to examine the effect of NHT on prostate volume before permanent prostate brachytherapy (PPB), and determine associated predictive factors.
Material and methods : Between June 1998 and April 2012, a total of 1,110 patients underwent PPB and 207 patients underwent NHT. Of these, 189 (91.3%) underwent detailed planimetric transrectal ultrasound before and after NHT prior to PPB. Regression analysis was used to assess predictors of absolute and percentage change in prostate volume after NHT.
Results: The median duration of NHT was 4.9 months with inter quartile range (IQR), 4.2-6.6 months. Prostate-specific antigen (PSA) reduced by a median of 97% following NHT. The mean prostate volume before NHT was 62.5 ± 22.1 cm 3 (IQR: 46-76 cm 3 ), and after NHT, it was 37.0 ± 14.5 cm 3 (IQR: 29-47 cm 3 ). The mean prostate volume reduction was 23.4 cm 3 (35.9%). Absolute prostate volume reduction was positively correlated with initial volume and inversely correlated with T-stage, Gleason score, and NCCN risk group. In multivariate regression analyses, initial prostate volume (p < 0.001) remained as a significant predictor of absolute and percent prostate volume reduction. Total androgen suppression was associated with greater percent prostate volume reduction than luteinizing hormone releasing hormone agonist (LHRHa) alone (p = 0.001).
Conclusions : Prostate volume decreased by approximately one third after 4.9 months of NHT, with total androgen suppression found to be more efficacious in maximizing cytoreduction than LHRHa alone. Initial prostate volume is the greatest predictor for prostate volume reduction
Salinity variations in the northern Coorong Lagoon, South Australia: Significant changes in the ecosystem following human alteration to the natural water regime
European settlement and drought have significantly impacted the hydrology of the Coorong, a shallow coastal lagoon complex in South Australia, which is part of a terminal wetland at the mouth of the River Murray. An increased salinity associated with lower water levels and progressive isolation from ocean flushes contributed to a severe decline in ecological diversity over the past decades. Here we have conducted a molecular and stable isotopic study of a sedimentary core from the northern Coorong Lagoon spanning more than 5000 years to investigate the recent palaeoenvironmental history of the ecosystem. Major alterations were evident in many biogeochemical parameters in sediments deposited after the 1950s coinciding with the beginning of intensified water regulations. The most prominent shift occurred in δ13C profiles of C21–C33n-alkanes from average values of −23.5‰ to an average of −28.2‰.Further changes included decreases in carbon preference index (CPI) and average chain length (ACL) of the n-alkane series as well as significant increases in algal (e.g. C20 HBI, long chain alkenes and C29-alkadiene) and bacterial (e.g. 13C depleted short chain n-alkanes and hopanoids, δ13C: −35.9‰ to −30.1‰) derived hydrocarbons. Long chain n-alkanes with a strong odd/even predominance as observed here are typically attributed to terrigenous plants. In the Coorong however, terrigenous input to sedimentary OM is only minor. Therefore changes in the before mentioned parameters were attributed to a source transition from a major contribution of macrophytes towards predominantly microalgae and bacteria.δD values of C21–C33n-alkanes showed a general trend towards more enriched values in younger sediments, indicating an overall rising salinity. However, the most pronounced positive shift in these profiles again occurred after the 1950s. Altogether this study demonstrates that the recent human induced changes of the Coorong hydrology, compounded by a severe drought led to an increase in salinity and alterations of primary production which have been much more significant than natural variations occurring throughout the Holocene over several thousands of years
Biparametric versus Multiparametric MRI for Prostate Cancer Diagnosis:The PRIME Diagnostic Clinical Trial
Importance: Multiparametric magnetic resonance imaging (MRI), with or without prostate biopsy, has become the standard of care for diagnosing clinically significant prostate cancer. Resource capacity limits widespread adoption. Biparametric MRI, which omits the gadolinium contrast sequence, is a shorter and cheaper alternative offering time-saving capacity gains for health systems globally.Objective: To assess whether biparametric MRI is noninferior to multiparametric MRI for diagnosis of clinically significant prostate cancer.Design, Setting, and Participants: A prospective, multicenter, within-patient, noninferiority trial of biopsy-naive men from 22 centers (12 countries) with clinical suspicion of prostate cancer (elevated prostate-specific antigen [PSA] level and/or abnormal digital rectal examination findings) from April 2022 to September 2023, with the last follow-up conducted on December 3, 2024.Interventions: Participants underwent multiparametric MRI, comprising T2-weighted, diffusion-weighted, and dynamic contrast–enhanced (DCE) sequences. Radiologists reported abbreviated biparametric MRI first (T2-weighted and diffusion-weighted), blinded to the DCE sequence. After unblinding, radiologists reported the full multiparametric MRI. Patients underwent a targeted biopsy with or without systematic biopsy if either biparametric MRI or multiparametric MRI was suggestive of clinically significant prostate cancer.Main outcomes and measures: The primary outcome was the proportion of men with clinically significant prostate cancer. Secondary outcomes included the proportion of men with clinically insignificant cancer. The noninferiority margin was 5%.Results: Of 555 men recruited, 490 were included for primary outcome analysis. Median age was 65 (IQR, 59-70) years and median PSA level was 5.6 (IQR, 4.4-8.0) ng/mL. The proportion of patients with abnormal digital rectal examination findings was 12.7%. Biparametric MRI was noninferior to multiparametric MRI, detecting clinically significant prostate cancer in 143 of 490 men (29.2%), compared with 145 of 490 men (29.6%) (difference, −0.4 [95% CI, −1.2 to 0.4] percentage points; P = .50). Biparametric MRI detected clinically insignificant cancer in 45 of 490 men (9.2%), compared with 47 of 490 men (9.6%) with the use of multiparametric MRI (difference, −0.4 [95% CI, −1.2 to 0.4] percentage points). Central quality control demonstrated that 99% of scans were of adequate diagnostic quality.Conclusion and relevance: In men with suspected prostate cancer, provided image quality is adequate, an abbreviated biparametric MRI scan, with or without targeted biopsy, could become the new standard of care for prostate cancer diagnosis. With approximately 4 million prostate MRIs performed globally annually, adopting biparametric MRI could substantially increase scanner throughput and reduce costs worldwide.Trial registration: ClinicalTrials.gov Identifier: NCT0457184
Comparing biparametric to multiparametric MRI in the diagnosis of clinically significant prostate cancer in biopsy-naive men (PRIME): a prospective, international, multicentre, non-inferiority within-patient, diagnostic yield trial protocol
Introduction
Prostate MRI is a well-established tool for the diagnostic work-up for men with suspected prostate cancer (PCa). Current recommendations advocate the use of multiparametric MRI (mpMRI), which is composed of three sequences: T2-weighted sequence (T2W), diffusion-weighted sequence (DWI) and dynamic contrast-enhanced sequence (DCE). Prior studies suggest that a biparametric MRI (bpMRI) approach, omitting the DCE sequences, may not compromise clinically significant cancer detection, though there are limitations to these studies, and it is not known how this may affect treatment eligibility. A bpMRI approach will reduce scanning time, may be more cost-effective and, at a population level, will allow more men to gain access to an MRI than an mpMRI approach.
Methods
Prostate Imaging Using MRI±Contrast Enhancement (PRIME) is a prospective, international, multicentre, within-patient diagnostic yield trial assessing whether bpMRI is non-inferior to mpMRI in the diagnosis of clinically significant PCa. Patients will undergo the full mpMRI scan. Radiologists will be blinded to the DCE and will initially report the MRI using only the bpMRI (T2W and DWI) sequences. They will then be unblinded to the DCE sequence and will then re-report the MRI using the mpMRI sequences (T2W, DWI and DCE). Men with suspicious lesions on either bpMRI or mpMRI will undergo prostate biopsy. The main inclusion criteria are men with suspected PCa, with a serum PSA of ≤20 ng/mL and without prior prostate biopsy. The primary outcome is the proportion of men with clinically significant PCa detected (Gleason score ≥3+4 or Gleason grade group ≥2). A sample size of at least 500 patients is required. Key secondary outcomes include the proportion of clinically insignificant PCa detected and treatment decision
Global Variation in Magnetic Resonance Imaging Quality of the Prostate
Background
High variability in prostate MRI quality might reduce accuracy in prostate cancer detection.
Purpose
To prospectively evaluate the quality of MRI scanners taking part in the quality control phase of the global PRIME (Prostate Imaging Using MRI ± Contrast Enhancement) trial using the Prostate Imaging Quality (PI-QUAL) standardized scoring system, give recommendations on how to improve the MRI protocols, and establish whether MRI quality could be improved by these recommendations.
Materials and Methods
In the prospective clinical trial (PRIME), for each scanner, centers performing prostate MRI submitted five consecutive studies and the MRI protocols (phase I). Submitted data were evaluated in consensus by two expert genitourinary radiologists using the PI-QUAL scoring system that evaluates MRI diagnostic quality using five points (1 and 2 = nondiagnostic; 3 = sufficient; 4 = adequate, 5 = optimal) between September 2021 and August 2022. Feedback was provided for scanners not achieving a PI-QUAL 5 score, and centers were invited to resubmit new imaging data using the modified protocol (phase II). Descriptive comparison of outcomes was made between the MRI scanners, feedback provided, and overall PI-QUAL scores.
Results
In phase I, 41 centers from 18 countries submitted a total of 355 multiparametric MRI studies from 71 scanners, with nine (13%) scanners achieving a PI-QUAL score of 3, 39 (55%) achieving a score of 4, and 23 (32%) achieving a score of 5. Of the 48 (n = 71 [68%]) scanners that received feedback to improve, the dynamic contrast-enhanced sequences were those that least adhered to the Prostate Imaging Reporting and Data System, version 2.1, criteria (44 of 48 [92%]), followed by diffusion-weighted imaging (20 of 48 [42%]) and T2-weighted imaging (19 of 48 [40%]). In phase II, 36 centers from 17 countries resubmitted revised studies, resulting in a total of 62 (n = 64 [97%]) scanners with a final PI-QUAL score of 5.
Conclusion
Substantial variation in global prostate MRI acquisition parameters as a measure of quality was observed, particularly with DCE sequences. Basic evaluation and modifications to MRI protocols using PI-QUAL can lead to substantial improvements in quality
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