165 research outputs found
Novel actions of next-generation taxanes benefit advanced stages of prostate cancer.
PURPOSE: To improve the outcomes of patients with castration-resistant prostate cancer (CRPC), there is an urgent need for more effective therapies and approaches that individualize specific treatments for patients with CRPC. These studies compared the novel taxane cabazitaxel with the previous generation docetaxel, and aimed to determine which tumors are most likely to respond.
EXPERIMENTAL DESIGN: Cabazitaxel and docetaxel were compared via in vitro modeling to determine the molecular mechanism, biochemical and cell biologic impact, and cell proliferation, which was further assessed ex vivo in human tumor explants. Isogenic pairs of RB knockdown and control cells were interrogated in vitro and in xenograft tumors for cabazitaxel response.
RESULTS: The data herein show that (i) cabazitaxel exerts stronger cytostatic and cytotoxic response compared with docetaxel, especially in CRPC; (ii) cabazitaxel induces aberrant mitosis, leading to pyknotic and multinucleated cells; (iii) taxanes do not act through the androgen receptor (AR); (iv) gene-expression profiling reveals distinct molecular actions for cabazitaxel; and (v) tumors that have progressed to castration resistance via loss of RB show enhanced sensitivity to cabazitaxel.
CONCLUSIONS: Cabazitaxel not only induces improved cytostatic and cytotoxic effects, but also affects distinct molecular pathways, compared with docetaxel, which could underlie its efficacy after docetaxel treatment has failed in patients with CRPC. Finally, RB is identified as the first potential biomarker that could define the therapeutic response to taxanes in metastatic CRPC. This would suggest that loss of RB function induces sensitization to taxanes, which could benefit up to 50% of CRPC cases
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First Report of NRG Oncology/Radiation Therapy Oncology Group 0622: A Phase 2 Trial of Samarium-153 Followed by Salvage Prostatic Fossa Irradiation in High-Risk Clinically Nonmetastatic Prostate Cancer After Radical Prostatectomy.
PURPOSE: To investigate the utility of 153Sm lexidronam (Quadramet) in the setting of men with prostate cancer status post radical prostatectomy who develop biochemical failure with no clinical evidence of osseous metastases.
PATIENTS AND METHODS: Trial NRG Oncology RTOG 0622 is a single-arm phase 2 trial that enrolled men with pT2-T4, N0-1, M0 prostate cancer status post radical prostatectomy, who meet at least 1 of these biochemical failure criteria: (1) prostate-specific antigen (PSA) \u3e 1.0 ng/mL; (2) PSA \u3e 0.2 ng/mL if Gleason score 9 to 10; or (3) PSA \u3e 0.2 ng/mL if N1. Patients received 153Sm (2.0 mCi/kg intravenously Ă— 1) followed by salvage external beam radiation therapy (EBRT) to the prostatic fossa (64.8-70.2 Gy in 1.8-Gy daily fractions). No androgen deprivation therapy was allowed. The primary objective was PSA response within 12 weeks of receiving 153Sm. The secondary objectives were to: (1) assess the completion rate for the regimen of 153Sm and EBRT; (2) evaluate the hematologic toxicity and other adverse events (AEs) at 12 and 24 weeks; and (3) determine the freedom from progression rate at 2 years.
RESULTS: A total of 60 enrolled eligible patients were included in this analysis. Median follow-up was 3.97 years. A PSA response was achieved in 7 of 52 evaluable patients (13.5%), compared with the 25% hypothesized. The 2-year freedom from progression rate was 25.5% (95% confidence interval 14.4%-36.7%), and the biochemical failure rate was 64.4% (95% CI 50.5%-75.2%). Samarium-153 was well tolerated, with 16 (of 60) grade 3 to 4 hematologic AEs and no grade 5 hematologic AEs. Radiation therapy was also well tolerated, with no grade 3 to 5 acute radiation therapy-related AEs and 1 grade 3 to 4 and no grade 5 late radiation therapy-related AEs.
CONCLUSIONS: Trial NRG Oncology RTOG 0622 did not meet its primary endpoint of PSA response, although the regimen of 153Sm and salvage EBRT was well tolerated. Although the toxicity profile supports study of 153Sm in high-risk disease, it may not be beneficial in men receiving EBRT
Costs of Early Adjuvant Radiation Therapy After Radical Prostatectomy: A Decision Analysis
Purpose/Objective(s): Prospective, randomized trials support adjuvant radiation therapy (RT) for adverse pathologic features after radical prostatectomy (RP). However, adjuvant RT is not universally delivered in this setting. Criticisms of adjuvant RT include toxicity, financial costs, potential overtreatment, and effectiveness of salvage RT. The objective of this study was to construct a decision analytic model to estimate real world cost of RT vs. no RT within the context of the effectiveness of early adjuvant RT for prostate patients based on published clinical results of the Southwest Oncology Group prospective trial of adjuvant RT (SWOG 8794).
American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C
Simple Frameshifts in MIS Postoperative Pain Management Significantly Reduce Opiate Prescriptions
Aims for Improvement The intervention aimed to reduce narcotics provided to patients after MIS by reducing number of narcotic prescriptions and amount prescribed by 25% without affecting patientreported pain scores Usage measured in Morphine Equivalent Doses (MED) MED and pain score assessed at 3 time points: post-op day 1 (POD1), discharge (D/C) and follow-up (FU) apt Pre- and Post-intervention cohorts - Month 1 (Pre-intervention): 21 patients and Month 2 (Post-intervention): 30 patient
IGRT After Prostatectomy: Evaluation of Corrective Shifts and Toxicity Using Online Cone Beam CT vs. Weekly Port Films for Target Localization
Purpose/Objective(s): Image guidance (IG) may permit higher radiotherapy (RT) doses (\u3e65 Gy) after radical prostatectomy (RP) without increased toxicity, with improved accuracy and smaller margins. Conebeam (CBCT) allows IGRT with volumetric images. This study evaluated CBCT shifts and toxicity after conformal IGRT, compared to RT with port films.
American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C
PARP-1 regulates DNA repair factor availability.
PARP-1 holds major functions on chromatin, DNA damage repair and transcriptional regulation, both of which are relevant in the context of cancer. Here, unbiased transcriptional profiling revealed the downstream transcriptional profile of PARP-1 enzymatic activity. Further investigation of the PARP-1-regulated transcriptome and secondary strategies for assessing PARP-1 activity in patient tissues revealed that PARP-1 activity was unexpectedly enriched as a function of disease progression and was associated with poor outcome independent of DNA double-strand breaks, suggesting that enhanced PARP-1 activity may promote aggressive phenotypes. Mechanistic investigation revealed that active PARP-1 served to enhance E2F1 transcription factor activity, and specifically promoted E2F1-mediated induction of DNA repair factors involved in homologous recombination (HR). Conversely, PARP-1 inhibition reduced HR factor availability and thus acted to induce or enhance BRCA-ness . These observations bring new understanding of PARP-1 function in cancer and have significant ramifications on predicting PARP-1 inhibitor function in the clinical setting
Genetic relationship of diarrheagenic Escherichia coli pathotypes among the enteropathogenic Escherichia coli O serogroup
Preventing Prostate Biopsy Complications: to Augment or to Swab?
Aims for Improvement The aim of this study was to determine the antibiotic prophylaxis associated with the fewest infectious complications following prostate biopsy Determining the safest method allows the Jefferson Department of Urology to modify its biopsy protocol and improve the rate of post-biopsy complication
Guidance for the Conduct and Reporting of Clinical Trials of Breast Milk Substitutes
Question What is the best way to ensure the validity of clinical trials of breast milk substitutes while protecting trial participants? Findings Through a Delphi consensus project, guidance was developed to address issues specific to trials of breast milk substitutes assessing growth and tolerance, as well as trials of breast milk substitutes with other objectives. This consensus guidance summarizes best practice for the design, conduct, analysis, and reporting of trials of breast milk substitutes. Meaning Use of this guidance, in conjunction with existing clinical trial regulations, should enhance the quality and validity of trials of breast milk substitutes, protect trial participants, and support the evidence base for infant nutrition recommendations. This consensus guidance summarizes best practice for the design, conduct, analysis, and reporting of trials of breast milk substitutes. Importance Breast milk substitutes (BMS) are important nutritional products evaluated in clinical trials. Concerns have been raised about the risk of bias in BMS trials, the reliability of claims that arise from such trials, and the potential for BMS trials to undermine breastfeeding in trial participants. Existing clinical trial guidance does not fully address issues specific to BMS trials. Objectives To establish new methodological criteria to guide the design, conduct, analysis, and reporting of BMS trials and to support clinical trialists designing and undertaking BMS trials, editors and peer reviewers assessing trial reports for publication, and regulators evaluating the safety, nutritional adequacy, and efficacy of BMS products. Design, Setting, and Participants A modified Delphi method was conducted, involving 3 rounds of anonymous questionnaires and a face-to-face consensus meeting between January 1 and October 24, 2018. Participants were 23 experts in BMS trials, BMS regulation, trial methods, breastfeeding support, infant feeding research, and medical publishing, and were affiliated with institutions across Europe, North America, and Australasia. Guidance development was supported by an industry consultation, analysis of methodological issues in a sample of published BMS trials, and consultations with BMS trial participants and a research ethics committee. Results An initial 73 criteria, derived from the literature, were sent to the experts. The final consensus guidance contains 54 essential criteria and 4 recommended criteria. An 18-point checklist summarizes the criteria that are specific to BMS trials. Key themes emphasized in the guidance are research integrity and transparency of reporting, supporting breastfeeding in trial participants, accurate description of trial interventions, and use of valid and meaningful outcome measures. Conclusions and Relevance Implementation of this guidance should enhance the quality and validity of BMS trials, protect BMS trial participants, and better inform the infant nutrition community about BMS products.Peer reviewe
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Incorporating mpMRI biopsy data into established pre-RP nomograms: potential impact of an increasingly common clinical scenario
Background: We examine the practical application of multiparametric MRI (mpMRI) prostate biopsy data using established pre-RP nomograms and its potential implications on RP intraoperative decision-making. We hypothesize that current nomograms are suboptimal in predicting outcomes with mpMRI targeted biopsy (TBx) data.
Materials and methods: Patients who underwent mpMRI-based TBx prior to RP were assessed using the MSKCC and Briganti nomograms with the following iterations: (1) Targeted (T) (targeted only), (2) Targeted and Systematic (TS) and (3) Targeted Augmented (TA) (targeted core data; assumed negative systematic cores for 12 total cores). Nomogram outcomes, lymph node involvement (LNI), extracapsular extension (ECE), organ-confined disease (OCD), seminal vesicle invasion (SVI), were compared across iterations. Clinically significant impact on management was defined as a change in LNI risk above or below 2% (Δ2) or 5% (Δ5).
Results: A total of 217 men met inclusion criteria. Overall, the TA iteration had more conservative nomogram outcomes than the T. Moreover, TA better predicted RP pathology for all four outcomes when compared with the T. In the entire cohort, Δ2 and Δ5 were 16.6–25.8% and 20.3–39.2%, respectively. In the subset of 190 patients with targeted and systematic cores, TA was a better approximation of TS outcomes than T in 71% (MSKCC) and 82% (Briganti) of patients.
Conclusion: In established pre-RP nomograms, mpMRI-based TBx often yield variable and discordant results when compared with systematic biopsies. Future nomograms must better incorporate mpMRI TBx core data. In the interim, augmenting TBx data may serve to bridge the gap
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