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Background

Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.

Objective

To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.

Design, setting, and participants

We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.

Outcome measurements and statistical analysis

We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.

Results and limitations

The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.

Conclusions

mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.

Patient summary

Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging.  相似文献   
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The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed.  相似文献   
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ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics.  相似文献   
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Background

In the era of increasing scrutiny of delivery of quality care, efforts to decrease surgical overtreatment of insignificant prostate cancer (iCaP) continue.

Objective

To quantify the incidence of surgical overtreatment over time among a contemporary series of men diagnosed with CaP.

Methods

We retrospectively reviewed the medical records and pathologic specimens for men with CaP who underwent radical prostatectomy between January 2009 and December 2016 at a tertiary referral center. Overtreatment, defined as presence of iCaP in radical prostatectomy specimens, was the primary endpoint. iCaP was defined as a tumor of Gleason score no more than 6 and a tumor diameter ≤10mm (volume <0.5 cc). Independent predictors of iCaP were determined using a multivariable model.

Results

A total of 1,283 men were eligible for analysis. Overtreatment was found in 86 (6.7%) patients. The frequency of overtreatment significantly decreased from 15% (24/165) in 2009 to 3% (4/134) of patients in 2016 (P < 0.001). In the multivariable analysis, prostate-specific antigen density ≥0.15 vs. <0.15 (odds ratio [OR] 0.30, 95% confidence interval [CI] 0.15–0.64, P < 0.01), biopsy Gleason score 3+4 vs. 3+3 (OR 0.15, 95% CI 0.08–0.29, P < 0.01), African American vs. White ethnicity (OR 0.13, 95% CI 0.02–0.96, P = 0.045), and year of surgery (OR 0.88, 95% CI 0.77–0.99, P = 0.03) remained significant predictors of iCaP at surgery. Over the years of study, the odds of overtreatment decreased by 12% annually (OR 0.88, 95 CI 0.77–0.99, P = 0.03). At the same time, the pathological evidence of advanced disease at surgery (≥T3a with/without lymph node involvement) remained unchanged.

Comment

Surgical overtreatment of CaP has declined to a rate of approximately 3% at this tertiary referral center; further decline is likely. The decline probably has a multifactorial explanation: decreased rate of overdiagnosis, better patient selection for surgery, or change in the referral pattern.  相似文献   
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Gheita  Tamer A  Sayed  Safaa  Azkalany  Gada S  Abaza  Nouran  Hammam  Nevin  Eissa  AH 《Clinical rheumatology》2018,37(3):757-763
Clinical Rheumatology - The objective of this study is to assess toll-like receptor-9 (TLR9) expression in CD3-positive T lymphocytes and CD19-positive B lymphocytes in systemic sclerosis (SSc)...  相似文献   
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Background

Neoadjuvant chemotherapy (NAC) has been shown to improve survival in patients with urothelial carcinoma (UC). However, there are a subset of patients who do not respond or progress despite systemic treatment.

Methods

Data from the National Cancer Database on patients who underwent a radical cystectomy (RC) with or without NAC from 2006 to 2013 were abstracted. Covariates were balanced using inverse probability weighting methods. The primary outcome of overall survival in patients with residual disease by stage was evaluated using 90-day conditional landmark analysis and Cox proportional hazards modeling. Secondary outcome of predictors of residual disease was evaluated using multivariable logistic regression analysis.

Results

A total of 20,128 patients met our inclusion criteria; 16,058 patients underwent RC only (80%) and 4070 underwent RC with NAC (20%). Patients who received NAC were younger and healthier, treated at an academic center, and presented with higher stage. NAC was associated with improved overall survival amongst patients with cT3-4aN0 (HR 0.84 95% CI 0.73–0.97; p?=?0.02) and cN+ (HR 0.70, 95% CI 0.58–0.86; p?=?0.001). Predictors of no residual disease were NAC (OR 0.17, 95% CI 0.14–0.21; p?<?0.001) and treatment at an academic facility (OR 0.47, 95% CI 0.37–0.60; p?<?0.001). Patients with cT3-4a or cN+ had increased odds of having residual UC (OR 2.01, 95% CI 1.53–2.64; p?<?0.001, and OR 2.14, 95% CI 1.43–3.21; p?<?0.001, respectively) compared with cT2.

Conclusion

In patients with residual UC, NAC is associated with a significant survival benefit in higher stage disease only. Furthermore, those treated with NAC or at an academic center were less likely to have residual disease. Given the toxicity of NAC, more prudent patient selection for NAC is warranted and requires further study.
  相似文献   
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