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BACKGROUND: The inclusion criterion for active surveillance (AS) is low- or intermediate-risk prostate cancer. The predictive value of the presence of a suspicious lesion at magnetic resonance imaging (MRI) at the time of inclusion is insufficiently known. OBJECTIVE: To evaluate the percentage of patients needing active treatment stratified by the presence or absence of a suspicious lesion at baseline MRI. DESIGN SETTING AND PARTICIPANTS: A retrospective analysis of the data from the multicentric AS GAP3 Consortium database was conducted. The inclusion criteria were men with grade group (GG) 1 or GG 2 prostate cancer combined with prostate-specific antigen <20 ng/ml. We selected a subgroup of patients who had MRI at baseline and for whom MRI results and targeted biopsies were used for AS eligibility. Suspicious MRI was defined as an MRI lesion with Prostate Imaging Reporting and Data System (PI-RADS)/Likert ≥3 and for which targeted biopsies did not exclude the patient for AS. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was treatment free survival (FS). The secondary outcomes were histological GG progression FS and continuation of AS (discontinuation FS). RESULTS AND LIMITATIONS: The study cohort included 2119 patients (1035 men with nonsuspicious MRI and 1084 with suspicious MRI) with a median follow-up of 23 (12-43) mo. For the whole cohort, 3-yr treatment FS was 71% (95% confidence interval [CI]: 69-74). For nonsuspicious MRI and suspicious MRI groups, 3-yr treatment FS rates were, respectively, 80% (95% CI: 77-83) and 63% (95% CI: 59-66). Active treatment (hazard ratio [HR] = 2.0, p < 0.001), grade progression (HR = 1.9, p < 0.001), and discontinuation of AS (HR = 1.7, p < 0.001) were significantly higher in the suspicious MRI group than in the nonsuspicious MRI group. CONCLUSIONS: The risks of switching to treatment, histological progression, and AS discontinuation are higher in cases of suspicious MRI at inclusion. PATIENT SUMMARY: Among

Background: Careful assessment of the reasons for discontinuation of active surveillance (AS) is required for men with prostate cancer (PCa). Objective(s): Using Movember's Global Action Plan Prostate Cancer Active Surveillance initiative (GAP3) database, we report on reasons for AS discontinuation. Design, setting, and participants: We compared data from 10 296 men on AS from 21 centres across 12 countries. Outcome measurements and statistical analysis: Cumulative incidence methods were used to estimate the cumulative incidence rates of AS discontinuation. Results and limitations: During 5-yr follow-up, 27.5% (95% confidence interval [CI]: 26.4-28.6%) men showed signs of disease progression, 12.8% (95% CI: 12.0-13.6%) converted to active treatment without evidence of progression, 1.7% (95% CI: 1.5-2.0%) continued to watchful waiting, and 1.7% (95% CI: 1.4-2.1%) died from other causes. Of the 7049 men who remained on AS, 2339 had follow-up for >5 yr, 4561 had follow-up for <5 yr, and 149 were lost to follow-up. Cumulative incidence of progression was 27.5% (95% CI: 26.4-28.6%) at 5 yr and 38.2% (95% CI: 36.7-39.9%) at 10 yr. A limitation is that not all centres were included due to limited information on the reason for discontinuation and limited follow-up. Conclusion(s): Our descriptive analyses of current AS practices worldwide showed that 43.6% of men drop out of AS during 5-yr follow-up, mainly due to signs of disease progression. Improvements in selection tools for AS are thus needed to correctly allocate men with PCa to AS, which will also reduce discontinuation due to conversion to active treatment without evidence of disease progression. Patient Summary: Our assessment of a worldwide database of men with prostate cancer (PCa) on active surveillance (AS) shows that 43.6% drop out of AS within 5 yr, mainly due to signs of disease progression. Better tools are needed to select and monitor men with PCa as part of AS. After about 5 yr, about 56% of men were still

Two active surveillance risk calculators to predict disease reclassification on prostate biopsy are externally validated by the Movember Foundation's Global Action Plan (GAP3) consortium. They proved to be clinically useful and could reduce unnecessary biopsies, but need recalibration to local settings. Background: Men with prostate cancer (PCa) on active surveillance (AS) are followed through regular prostate biopsies, a burdensome and often unnecessary intervention, not without risks. Identifying men with at a low risk of disease reclassification may help reduce the number of biopsies. Objective(s): To assess the external validity of two Canary Prostate Active Surveillance Study Risk Calculators (PASS-RCs), which estimate the probability of reclassification (Gleason grade >=7 with or without >34% of biopsy cores positive for PCa) on a surveillance biopsy, using a mix of months since last biopsy, age, body mass index, prostate-specific antigen, prostate volume, number of prior negative biopsies, and percentage (or ratio) of positive cores on last biopsy. Design, setting, and participants: We used data up to November 2017 from the Movember Foundation's Global Action Plan (GAP3) consortium, a global collaboration between AS studies. Outcome measurements and statistical analysis: External validity of the PASS-RCs for estimating reclassification on biopsy was assessed by calibration, discrimination, and decision curve analyses. Results and limitations: Five validation cohorts (Prostate Cancer Research International: Active Surveillance, Johns Hopkins, Toronto, Memorial Sloan Kettering Cancer Center, and University of California San Francisco), comprising 5105 men on AS, were eligible for analysis. The individual cohorts comprised 429-2416 men, with a median follow-up between 36 and 84 mo, in both community and academic practices mainly from western countries. Abilities of the PASS-RCs to discriminate between men with and without reclassification on biopsy were reasonab

An improved crack velocity monitoring procedure able to cope with irregular crack initiation and crack acceleration in ceramics has been developed and used to obtain KId measurements for silicon nitride, polycrystalline alumina and magnesia. The system allowed extended recording times at fast sweep rates for open-camera single shot oscilloscope work. Velocity data was obtained for three point bend tests on PMMA using surface resistance grids to monitor crack growth and an auto-resistance technique was used for velocity measurements during bend tests on tool steels. For the latter, the data was interpreted using an iterative procedure based on an empirical estimate of the functional dependence of the dynamic potential output. Consistent and reproducible data was obtained using auto-resistive crack length measurements for fast fracture in bending, tension and combined impact-tension tests but the interpretation of the resulting data requires further clarification.

Combined tensile-impact tests have been performed. It was found that a wide range of crack velocity was encompassed and the detailed crack acceleration behavior was unpre-dictable. An improved crack-velocity monitoring procedure for single-shot oscilloscope work has been devised that gives an extended record time at fast sweep rates. This was accomplished by using the signal to modulate the radius of a circular time base and the trigger to intensify a pre-blanked trace. Calibration procedures utilising the self-resistance of the cracking specimen to monitor crack growth have been completed and a recording system has been developed to monitor pretrigger and post trigger crack velocity data. (Author, modified-PL)