Search

INTRODUCTION: Sex hormones have been implicated in the etiology of a number of diseases. To better understand disease etiology and the mechanisms of disease-risk factor associations, this analysis aimed to investigate the associations of anthropometric, sociodemographic and behavioural factors with a range of circulating sex hormones and sex hormone-binding globulin. METHODS: Statistical analyses of individual participant data from 12,330 male controls aged 25-85 years from 25 studies involved in the Endogenous Hormones Nutritional Biomarkers and Prostate Cancer Collaborative Group. Analysis of variance was used to estimate geometric means adjusted for study and relevant covariates. RESULTS: Older age was associated with higher concentrations of sex hormone-binding globulin and dihydrotestosterone and lower concentrations of dehydroepiandrosterone sulfate, free testosterone, androstenedione, androstanediol glucuronide and free estradiol. Higher body mass index was associated with higher concentrations of free estradiol, androstanediol glucuronide, estradiol and estrone and lower concentrations of dihydrotestosterone, testosterone, sex hormone-binding globulin, free testosterone, androstenedione and dehydroepiandrosterone sulfate. Taller height was associated with lower concentrations of androstenedione, testosterone, free testosterone and sex hormone-binding globulin and higher concentrations of androstanediol glucuronide. Current smoking was associated with higher concentrations of androstenedione, sex hormone-binding globulin and testosterone. Alcohol consumption was associated with higher concentrations of dehydroepiandrosterone sulfate, androstenedione and androstanediol glucuronide. East Asians had lower concentrations of androstanediol glucuronide and African Americans had higher concentrations of estrogens. Education and marital status were modestly associated with a small number of hormones. CONCLUSION: Circulating sex hormones in men are strongly associated

BackgroundMagnetic resonance imaging (MRI) is emerging as a robust, noninvasive method for detecting and characterizing prostate cancer (PCa), but limitations remain in its ability to distinguish cancerous from non-cancerous tissue. We evaluated the performance of a novel MRI technique, restriction spectrum imaging (RSI-MRI), to quantitatively detect and grade PCa compared with current standard-of-care MRI.MethodsIn a retrospective evaluation of 33 patients with biopsy-proven PCa who underwent RSI-MRI and standard MRI before radical prostatectomy, receiver-operating characteristic (ROC) curves were performed for RSI-MRI and each quantitative MRI term, with area under the ROC curve (AUC) used to compare each term's ability to differentiate between PCa and normal prostate. Spearman rank-order correlations were performed to assess each term's ability to predict PCa grade in the radical prostatectomy specimens.ResultsRSI-MRI demonstrated superior differentiation of PCa from normal tissue, with AUC of 0.94 and 0.85 for RSI-MRI and conventional diffusion MRI, respectively (P=0.04). RSI-MRI also demonstrated superior performance in predicting PCa aggressiveness, with Spearman rank-order correlation coefficients of 0.53 (P=0.002) and -0.42 (P=0.01) for RSI-MRI and conventional diffusion MRI, respectively, with tumor grade.ConclusionsRSI-MRI significantly improves upon current noninvasive PCa imaging and may potentially enhance its diagnosis and characterization.

BackgroundMagnetic resonance imaging (MRI) is emerging as a robust, noninvasive method for detecting and characterizing prostate cancer (PCa), but limitations remain in its ability to distinguish cancerous from non-cancerous tissue. We evaluated the performance of a novel MRI technique, restriction spectrum imaging (RSI-MRI), to quantitatively detect and grade PCa compared with current standard-of-care MRI.MethodsIn a retrospective evaluation of 33 patients with biopsy-proven PCa who underwent RSI-MRI and standard MRI before radical prostatectomy, receiver-operating characteristic (ROC) curves were performed for RSI-MRI and each quantitative MRI term, with area under the ROC curve (AUC) used to compare each term's ability to differentiate between PCa and normal prostate. Spearman rank-order correlations were performed to assess each term's ability to predict PCa grade in the radical prostatectomy specimens.ResultsRSI-MRI demonstrated superior differentiation of PCa from normal tissue, with AUC of 0.94 and 0.85 for RSI-MRI and conventional diffusion MRI, respectively (P=0.04). RSI-MRI also demonstrated superior performance in predicting PCa aggressiveness, with Spearman rank-order correlation coefficients of 0.53 (P=0.002) and -0.42 (P=0.01) for RSI-MRI and conventional diffusion MRI, respectively, with tumor grade.ConclusionsRSI-MRI significantly improves upon current noninvasive PCa imaging and may potentially enhance its diagnosis and characterization.

Purpose: Diffusion imaging in the prostate is susceptible to distortion from B0 inhomogeneity. Distortion correction in prostate imaging is not routinely performed, resulting in diffusion images without accurate localization of tumors. We performed and evaluated distortion correction for diffusion imaging in the prostate. Materials and methods: 28 patients underwent pre-operative MRI (T2, Gadolinium perfusion, diffusion at b=800s/mm2). The restriction spectrum protocol parameters included b-values of 0, 800, 1500, and 4000s/mm2 in 30 directions for each nonzero b-value. To correct for distortion, forward and reverse trajectories were collected at b=0s/mm2. Distortion maps were generated to reflect the offset of the collected data versus the corrected data. Whole-mount histology was available for correlation. Results: Across the 27 patients evaluated (excluding one patient due to data collection error), the average root mean square distortion distance of the prostate was 3.1. mm (standard deviation, 2.2. mm; and maximum distortion, 12. mm). Conclusion: Improved localization of prostate cancer by MRI will allow better surgical planning, targeted biopsies and image-guided treatment therapies. Distortion distances of up to 12. mm due to standard diffusion imaging may grossly misdirect treatment decisions. Distortion correction for diffusion imaging in the prostate improves tumor localization.

BackgroundStandard magnetic resonance imaging (MRI) of the prostate lacks sensitivity in the diagnosis and staging of prostate cancer (PCa). To improve the operating characteristics of prostate MRI in the detection and characterization of PCa, we developed a novel, enhanced MRI diffusion technique using restriction spectrum imaging (RSI-MRI).MethodsWe compared the efficacy of our novel RSI-MRI technique with standard MRI for detecting extraprostatic extension (EPE) among 28 PCa patients who underwent MRI and RSI-MRI prior to radical prostatectomy, 10 with histologically proven pT3 disease. RSI cellularity maps isolating the restricted isotropic water fraction were reconstructed based on all b-values and then standardized across the sample with z-score maps. Distortion correction of the RSI maps was performed using the alternating phase-encode technique.Results27 patients were evaluated, excluding one patient where distortion could not be performed. Preoperative standard MRI correctly identified extraprostatic the extension in two of the nine pT3 (22%) patients, whereas RSI-MRI identified EPE in eight of nine (89%) patients. RSI-MRI correctly identified pT2 disease in the remaining 18 patients.ConclusionsIn this proof of principle study, we conclude that our novel RSI-MRI technology is feasible and shows promise for substantially improving PCa imaging. Further translational studies of prostate RSI-MRI in the diagnosis and staging of PCa are indicated.

BackgroundStandard magnetic resonance imaging (MRI) of the prostate lacks sensitivity in the diagnosis and staging of prostate cancer (PCa). To improve the operating characteristics of prostate MRI in the detection and characterization of PCa, we developed a novel, enhanced MRI diffusion technique using restriction spectrum imaging (RSI-MRI).MethodsWe compared the efficacy of our novel RSI-MRI technique with standard MRI for detecting extraprostatic extension (EPE) among 28 PCa patients who underwent MRI and RSI-MRI prior to radical prostatectomy, 10 with histologically proven pT3 disease. RSI cellularity maps isolating the restricted isotropic water fraction were reconstructed based on all b-values and then standardized across the sample with z-score maps. Distortion correction of the RSI maps was performed using the alternating phase-encode technique.Results27 patients were evaluated, excluding one patient where distortion could not be performed. Preoperative standard MRI correctly identified extraprostatic the extension in two of the nine pT3 (22%) patients, whereas RSI-MRI identified EPE in eight of nine (89%) patients. RSI-MRI correctly identified pT2 disease in the remaining 18 patients.ConclusionsIn this proof of principle study, we conclude that our novel RSI-MRI technology is feasible and shows promise for substantially improving PCa imaging. Further translational studies of prostate RSI-MRI in the diagnosis and staging of PCa are indicated.

Purpose: Diffusion imaging in the prostate is susceptible to distortion from B0 inhomogeneity. Distortion correction in prostate imaging is not routinely performed, resulting in diffusion images without accurate localization of tumors. We performed and evaluated distortion correction for diffusion imaging in the prostate. Materials and methods: 28 patients underwent pre-operative MRI (T2, Gadolinium perfusion, diffusion at b=800s/mm2). The restriction spectrum protocol parameters included b-values of 0, 800, 1500, and 4000s/mm2 in 30 directions for each nonzero b-value. To correct for distortion, forward and reverse trajectories were collected at b=0s/mm2. Distortion maps were generated to reflect the offset of the collected data versus the corrected data. Whole-mount histology was available for correlation. Results: Across the 27 patients evaluated (excluding one patient due to data collection error), the average root mean square distortion distance of the prostate was 3.1. mm (standard deviation, 2.2. mm; and maximum distortion, 12. mm). Conclusion: Improved localization of prostate cancer by MRI will allow better surgical planning, targeted biopsies and image-guided treatment therapies. Distortion distances of up to 12. mm due to standard diffusion imaging may grossly misdirect treatment decisions. Distortion correction for diffusion imaging in the prostate improves tumor localization.

BackgroundKnowledge of factors associated with the course of lower urinary tract symptoms (LUTS) before treatment is needed to inform preventive interventions. In a prospective study of elderly men untreated for LUTS, we identified factors associated with symptom progression and remission.MethodsIn community-dwelling US men aged ≥65 years, the American Urological Association Symptom Index (AUA-SI) was repeated four times, once at baseline (2000-2002) and then every 2 years thereafter. Analyses included 1740 men with all four AUA-SI assessments, who remained free from diagnosed prostate cancer, and who reported no treatment for LUTS or BPH during follow-up that averaged 6.9 (±0.4) years. LUTS change was determined with group-based trajectory modelingof the repeated AUA-SI measures. Multivariable logistic regression was then used to determine the baseline factors associated with progressing compared with stable trajectories, and with remitting compared with progressing trajectories. Lifestyle, body mass index (BMI) (kg/m(2)), mobility, mental health (Short-Form 12), medical history and prescription medications were considered for selection. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for variables in each model.ResultsWe identified 10 AUA-SI trajectories: 4 stable (1277 men, 73%), three progressing (345 men, 20%), two remitting (98 men, 6%) and one mixed (20 men, 1%). Men in progressing compared with stable trajectories were more likely to have mobility limitations (OR=2.0, 95% CI: 1.0-3.8), poor mental health (OR=1.9, 95% CI: 1.1-3.4), BMI≥25.0 kg m(-2) (OR=1.7, 95% CI: 1.0-2.8), hypertension (OR=1.5, 95% CI: 1.0-2.4) and back pain (OR=1.5, 95% CI: 1.0-2.4). Men in remitting compared with progressing trajectories more often used central nervous system medications (OR=2.3, 95% CI: 1.1-4.9) and less often had a history of problem drinking (OR=0.4, 95% CI: 0.2-0.9).ConclusionsSeveral non-urological lifestyle and health factors were independently

BackgroundKnowledge of factors associated with the course of lower urinary tract symptoms (LUTS) before treatment is needed to inform preventive interventions. In a prospective study of elderly men untreated for LUTS, we identified factors associated with symptom progression and remission.MethodsIn community-dwelling US men aged ≥65 years, the American Urological Association Symptom Index (AUA-SI) was repeated four times, once at baseline (2000-2002) and then every 2 years thereafter. Analyses included 1740 men with all four AUA-SI assessments, who remained free from diagnosed prostate cancer, and who reported no treatment for LUTS or BPH during follow-up that averaged 6.9 (±0.4) years. LUTS change was determined with group-based trajectory modelingof the repeated AUA-SI measures. Multivariable logistic regression was then used to determine the baseline factors associated with progressing compared with stable trajectories, and with remitting compared with progressing trajectories. Lifestyle, body mass index (BMI) (kg/m(2)), mobility, mental health (Short-Form 12), medical history and prescription medications were considered for selection. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for variables in each model.ResultsWe identified 10 AUA-SI trajectories: 4 stable (1277 men, 73%), three progressing (345 men, 20%), two remitting (98 men, 6%) and one mixed (20 men, 1%). Men in progressing compared with stable trajectories were more likely to have mobility limitations (OR=2.0, 95% CI: 1.0-3.8), poor mental health (OR=1.9, 95% CI: 1.1-3.4), BMI≥25.0 kg m(-2) (OR=1.7, 95% CI: 1.0-2.8), hypertension (OR=1.5, 95% CI: 1.0-2.4) and back pain (OR=1.5, 95% CI: 1.0-2.4). Men in remitting compared with progressing trajectories more often used central nervous system medications (OR=2.3, 95% CI: 1.1-4.9) and less often had a history of problem drinking (OR=0.4, 95% CI: 0.2-0.9).ConclusionsSeveral non-urological lifestyle and health factors were independently