Dr. Matthew  Somerville  Dds image

Dr. Matthew Somerville Dds

1240 S Westlake Blvd Ste. 139
Westlake Village CA 91361
805 732-2800
Medical School: Other - Unknown
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License #: 61864
NPI: 1821341819
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A randomised, double-blind study comparing the addition of bicalutamide with or without dutasteride to GnRH analogue therapy in men with non-metastatic castrate-resistant prostate cancer. - European journal of cancer (Oxford, England : 1990)
Bicalutamide blocks androgen action and is frequently used in men with non-metastatic, castration-resistant prostate cancer (CRPC). By reducing intracellular dihydrotestosterone, dutasteride (dual 5-alpha reductase inhibitor) could increase the effectiveness of bicalutamide in this setting. The objective of the study is therefore to prospectively evaluate dutasteride plus bicalutamide in men with asymptomatic, non-metastatic CRPC with rising prostate-specific antigen (PSA).Prostate cancer patients with rising PSA whilst on first-line androgen deprivation therapy (ADT) were randomised (1:1) in a double-blind trial to receive bicalutamide 50mg plus placebo or bicalutamide 50mg plus dutasteride 3.5mg once daily for 18 months. Randomisation was stratified by centre; treatment assignments were generated using GlaxoSmithKline's RandAll System. Subjects who completed 18 months could participate in the 2-year extension. Central laboratory and study sites/monitors remained treatment-blinded. Primary end-point was time to disease progression (TDP) up to 42 months (defined as PSA progression from baseline or nadir, radiographic disease progression, death from prostate cancer or receipt of rescue medication).There was no statistically significant difference in TDP in 127 men treated with bicalutamide/dutasteride (n=62) compared with bicalutamide/placebo (n=65) (hazard ratio (HR)=0.94 [95% confidence interval (CI) 0.61, 1.46]; p=0.79). The estimated median TDP was 425 days (95% CI 302, 858) in the bicalutamide/placebo group and 623 days (95% CI 369, 730) in the bicalutamide/dutasteride group. There was no statistically significant difference between the treatment groups for any secondary efficacy end-points, including time to treatment failure or PSA response. In the multivariate analysis, age, non-White race, higher baseline testosterone and lower baseline PSA were associated with longer TDP. Adverse events were comparable between treatment groups.In men with non-metastatic CRPC, adding dutasteride to bicalutamide did not significantly prolong TDP. Prospective data are provided concerning the common practice of using bicalutamide in this setting.Copyright © 2015 Elsevier Ltd. All rights reserved.
Burden of Illness in Prostate Cancer Patients with a Low-to-Moderate Risk of Progression: A One-Year, Pan-European Observational Study. - Prostate cancer
Objective. To assess the impact of low-to-moderate risk prostate cancer on patients' quality of life (QoL) at diagnosis and within the first year of treatment. Subjects and Methods. Men (n = 672) aged 50-75 years with prostate cancer (Gleason score ≤7, PSA ≤20 ng/mL and clinical staging T1c-T2b) were enrolled in five European countries. Patients completed five questionnaires, including EORTC Quality of Life Questionnaire-Prostate Cancer 25 (QLQ-PR25) and EORTC Quality of Life Questionnaire-Cancer 30 (QLQ-C30). Questionnaires were completed at baseline, at 3 months and 12 months after starting treatment. The primary endpoint was the change in QLQ-PR25 urinary symptoms subscale score from baseline to the assessment at 3 months. Results. Mean (SD) age was 65.0 (5.7) years and 400 (66%) men had Gleason score ≤6 prostate cancer. The most frequently used initial treatment was radical prostatectomy (71% of patients). QLQ-PR25 urinary symptoms subscale score was significantly increased at 3 months (P < 0.001), indicating that urinary symptoms worsened after treatment. The score was lower at 12 months than at 3 months, but it was still significantly higher than at baseline (P < 0.001). Hormonal treatment-related symptoms, sexual functioning, and sexual activity scores significantly worsened at 3 and 12 months (all P < 0.001). For the QLQ-C30 questionnaire, global health status/QoL score significantly decreased at month 3 but was not different from baseline by month 12. Scales for physical, role, and social functioning, and fatigue, showed significant deterioration at 3 and 12 months. Conclusions. Low-to-moderate risk prostate cancer may have a substantial effect on patients' QoL within one year following treatment.
Comparison of Classic and International Society of Urological Pathology 2005 Modified Gleason grading using needle biopsies from the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial. - Archives of pathology & laboratory medicine
Use of the International Society of Urological Pathology (ISUP) 2005 modified Gleason score may result in higher scores compared with the classic Gleason scoring system.To compare scores derived using the 2 scoring systems.On-study and for-cause biopsies were centrally reviewed and assigned a classic Gleason score in the Reduction by Dutasteride of prostate Cancer Events trial. Positive biopsies were reviewed by an independent pathologist in a secondary review using the ISUP 2005 modified Gleason score. The independent pathologist also recorded a classic Gleason score.In total, 1482/1507 (98%) positive biopsy results were independently reviewed. Scores assigned by the 2 pathologists (classic versus modified) agreed in 83% (1230 of 1481) of cases; 99% (1471 of 1481) of cancers were within ±1 of their previous score. Of discordant cases, similar numbers of biopsies were upgraded and downgraded in the secondary review, with minor differences in the score distributions. Interobserver agreement was good, with κ values ranging from 0.62 (95% confidence interval [CI], 0.56-0.67) to 0.70 (95% CI, 0.65-0.76). The overall number of high-grade tumors (Gleason score 8-10; n = 48) remained constant between reviews, with 3 fewer cases in the placebo group (n = 16) and 3 more in the dutasteride group (n = 32) in the secondary review. When comparing the independent pathologist's modified scores versus the classic, 17 of 1481 cancers (1.1%) were upgraded (including 9 of 17 upgrades [53%] to high-grade tumors).This analysis showed similar score distributions between the classic and modified Gleason scoring systems. The differences seen between the 2 pathologists' scores likely reflect differences in interpretation rather than the scoring system chosen.
Exact likelihood ratio and score confidence intervals for the binomial proportion. - Pharmaceutical statistics
Many methods are available for computing a confidence interval for the binomial parameter, and these methods differ in their operating characteristics. It has been suggested in the literature that the use of the exact likelihood ratio (LR) confidence interval for the binomial proportion should be considered. This paper provides an evaluation of the operating characteristics of the two-sided exact LR and exact score confidence intervals for the binomial proportion and compares these results to those for three other methods that also strictly maintain nominal coverage: Clopper-Pearson, Blaker, and Casella. In addition, the operating characteristics of the two-sided exact LR method and exact score method are compared with those of the corresponding asymptotic methods to investigate the adequacy of the asymptotic approximation.Copyright © 2013 John Wiley & Sons, Ltd.
The REDUCE Follow-Up Study: low rate of new prostate cancer diagnoses observed during a 2-year, observational, followup study of men who participated in the REDUCE trial. - The Journal of urology
The primary objective of the REDUCE (REduction by DUtasteride of prostate Cancer Events) Follow-Up Study was to collect data on the occurrence of newly diagnosed prostate cancers for 2 years beyond the 4-year REDUCE study.The 4-year REDUCE study evaluated prostate cancer risk reduction in men taking dutasteride. This 2-year observational study followed men from REDUCE with a clinic visit shortly after study conclusion and with up to 2 annual telephone calls during which patient reported data were collected regarding prostate cancer events, chronic medication use, prostate specific antigen levels and serious adverse events. No study drug was provided and all biopsies during the 2-year followup were performed for cause. The primary objective was to collect data on the occurrence of new biopsy detectable prostate cancers. Secondary end points included assessment of Gleason score and serious adverse events.A total of 2,751 men enrolled in the followup study with numbers similar to those of the REDUCE former treatment groups (placebo and dutasteride). Few new prostate cancers were detected during the 2-year followup period in either former treatment group. A greater number of cancers were detected in the former dutasteride group than in the former placebo group (14 vs 7 cases). No Gleason score 8-10 prostate cancers were detected in either former treatment group based on central pathology review. No new safety issues were identified during the study.Two years of followup of the REDUCE study cohort demonstrated a low rate of new prostate cancer diagnoses in the former placebo and dutasteride treated groups. No new Gleason 8-10 cancers were detected.Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Usefulness of prostate-specific antigen (PSA) rise as a marker of prostate cancer in men treated with dutasteride: lessons from the REDUCE study. - BJU international
To determine if dutasteride-treated men can be monitored safely and adequately for prostate cancer based on data from the Reduction by Dutasteride in Prostate Cancer Events (REDUCE) study. To analyse whether the use of treatment-specific criteria for repeat biopsy maintains the usefulness of prostate-specific antigen (PSA) level for detecting high grade cancers.The REDUCE study was a randomized, double-blind, placebo-controlled investigation of whether dutasteride (0.5 mg/day) reduced the risk of biopsy-detectable prostate cancer in men with a previous negative biopsy. The usefulness of PSA was evaluated using biopsy thresholds defined by National Comprehensive Cancer Network guidelines in the placebo group and any rise in PSA from nadir (the lowest PSA level achieved while in the study) in the dutasteride group. The number of cancers detected on biopsy in the absence of increased/suspicious PSA level as well as sensitivity, specificity, positive predictive value and negative predictive value for high grade prostate cancer detection were analysed by treatment group. Prostate cancer pathological characteristics were compared between men who did and did not meet biopsy thresholds.Of 8231 men randomized, 3305 (dutasteride) and 3424 (placebo) underwent at least one prostate biopsy during the study and were included in the analysis. If only men meeting biopsy thresholds underwent biopsy, 25% (47/191) of Gleason 7 and 24% (7/29) of Gleason 8-10 cancers would have been missed in the dutasteride group, and 37% (78/209) of Gleason 7 and 22% (4/18) Gleason 8-10 cancers would have been missed in the placebo group. In both groups, the incidence of Gleason 7 and Gleason 8-10 cancers generally increased with greater rises in PSA. Sensitivity of PSA kinetics was higher and specificity was lower for the detection of Gleason 7-10 cancers in men treated with dutasteride vs placebo. Men with Gleason 7 and Gleason 8-10 cancer meeting biopsy thresholds had greater numbers of positive cores, percent core involvement, and biopsy cancer volume vs men not meeting thresholds.Using treatment-specific biopsy thresholds, the present study shows that the ability of PSA kinetics to detect high grade prostate cancer is maintained with dutasteride compared with placebo in men with a previous negative biopsy. The sensitivity of PSA kinetics with dutasteride was similar to (Gleason 8-10) or higher than (Gleason 7-10) the placebo group; however, biopsy decisions based on a single increased PSA measurement from nadir in the dutasteride group resulted in a lower specificity compared with using a comparable biopsy threshold in the placebo group, indicating the importance of confirmation of PSA measurements.© 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.
Biopsy misidentification identified by DNA profiling in a large multicenter trial. - Journal of clinical oncology : official journal of the American Society of Clinical Oncology
The Reduction by Dutasteride of Prostate Cancer Events (REDUCE) prostate cancer risk reduction study randomly assigned 8,231 men to dutasteride or placebo for 4 years. Protocol-mandated biopsies were obtained after 2 and 4 years. After the discovery of three cases of biopsy sample misidentification in the first 2 years, all protocol-mandated biopsy samples were DNA tested to verify biopsy identity.Biopsy and blood DNA profiling was performed retrospectively for the year 2 scheduled biopsies and prospectively for the year 4 scheduled biopsies. Toward the end of year 2, multiple changes were made to improve sample handling and chain of custody.Of the 6,458 year 2 and 4,777 year 4 biopsies, 26 biopsies reflecting 13 sample handling errors at year 2 (0.4%) and one biopsy reflecting one sample handling error at year 4 (0.02%) were confirmed to be mismatched to the patient for whom they were originally submitted. Of 6,733 reference blood samples profiled, 31 (0.5%) were found to be mismatched to the patient's verified identity profile. Sample identification errors occurred at local research sites and central laboratories.Biopsy misidentification is a potential problem in clinical laboratories and clinical trials. Until now, biopsy misidentification has not been studied in the setting of a large, multinational clinical trial. In the REDUCE study, process improvement initiatives halfway through the trial dramatically reduced biopsy mismatches. The potential for biopsy mismatches in clinical trials and clinical practice is an under-recognized problem that requires rigorous attention to details of chain of custody and consideration of more widespread DNA identity testing.
The effect of dutasteride on the usefulness of prostate specific antigen for the diagnosis of high grade and clinically relevant prostate cancer in men with a previous negative biopsy: results from the REDUCE study. - The Journal of urology
We assessed whether dutasteride enhances the usefulness of total prostate specific antigen for diagnosing clinically significant prostate cancer.The 4-year REDUCE study evaluated the efficacy and safety of 0.5 mg dutasteride daily for prostate cancer risk reduction in men with a prostate specific antigen of 2.5 to 10.0 ng/ml and a negative prostate biopsy. Specificity, sensitivity, and positive and negative predictive values of prostate specific antigen for the diagnosis of prostate cancer were assessed.Final prostate specific antigen before biopsy and change from month 6 to final prostate specific antigen performed better for the diagnosis of Gleason score 7-10 tumors in men who received dutasteride vs placebo as assessed by the area under the ROC curves (0.700 vs 0.650, p = 0.0491; and 0.699 vs 0.593, p = 0.0001, respectively). Increases in prostate specific antigen were associated with a higher likelihood of biopsy detectable, Gleason score 7-10 and clinically significant (modified Epstein criteria) prostate cancer. Percentage decreases in prostate specific antigen from baseline to month 6 in the dutasteride arm did not predict prostate cancer overall or Gleason score 7-10 cancer.In men with a previously negative prostate biopsy, prostate specific antigen performed better during the 4-year study as a marker of prostate cancer in men who received dutasteride vs placebo. The degree of prostate specific antigen increase after 6 months was a better indicator of clinically significant cancer in the dutasteride arm than in the placebo arm. Conversely, the initial decrease in prostate specific antigen in men taking dutasteride did not predict the likelihood of prostate cancer.Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Effect of NRG1, GDNF, EGF and NGF in the migration of a Schwann cell precursor line. - Neurochemical research
The Schwann cells are the myelinating glia of the peripheral nervous system that originated during development from the highly motile neural crest. However, we do not know what the guidance signals for the Schwann cell precursors are. Therefore, we set to test some of the known neurotrophins that are expressed early in developing embryos and have been shown to be critical for the survival and patterning of developing glia and neurons. The goal of this study was to determine more specifically if GDNF, NRG1 and NGF are chemoattractants and/or chemokinetic molecules for a Schwann cell precursor line, the Spl201. We performed live chemoattraction assays, with imaging and also presented these molecules as part of their growing substrate. Our results show for the first time that GDNF and NRG1 are potent chemoattractive and chemokinetic molecules for these cells while NGF is a chemokinetic molecule stimulating their motility.
Effect of dutasteride on the risk of prostate cancer. - The New England journal of medicine
We conducted a study to determine whether dutasteride reduces the risk of incident prostate cancer, as detected on biopsy, among men who are at increased risk for the disease.In this 4-year, multicenter, randomized, double-blind, placebo-controlled, parallel-group study, we compared dutasteride, at a dose of 0.5 mg daily, with placebo. Men were eligible for inclusion in the study if they were 50 to 75 years of age, had a prostate-specific antigen (PSA) level of 2.5 to 10.0 ng per milliliter, and had had one negative prostate biopsy (6 to 12 cores) within 6 months before enrollment. Subjects underwent a 10-core transrectal ultrasound-guided biopsy at 2 and 4 years.Among 6729 men who underwent a biopsy or prostate surgery, cancer was detected in 659 of the 3305 men in the dutasteride group, as compared with 858 of the 3424 men in the placebo group, representing a relative risk reduction with dutasteride of 22.8% (95% confidence interval, 15.2 to 29.8) over the 4-year study period (P<0.001). Overall, in years 1 through 4, among the 6706 men who underwent a needle biopsy, there were 220 tumors with a Gleason score of 7 to 10 among 3299 men in the dutasteride group and 233 among 3407 men in the placebo group (P=0.81). During years 3 and 4, there were 12 tumors with a Gleason score of 8 to 10 in the dutasteride group, as compared with only 1 in the placebo group (P=0.003). Dutasteride therapy, as compared with placebo, resulted in a reduction in the rate of acute urinary retention (1.6% vs. 6.7%, a 77.3% relative reduction). The incidence of adverse events was similar to that in studies of dutasteride therapy for benign prostatic hyperplasia, except that in our study, as compared with previous studies, the relative incidence of the composite category of cardiac failure was higher in the dutasteride group than in the placebo group (0.7% [30 men] vs. 0.4% [16 men], P=0.03).Over the course of the 4-year study period, dutasteride reduced the risk of incident prostate cancer detected on biopsy and improved the outcomes related to benign prostatic hyperplasia. ( number, NCT00056407.)2010 Massachusetts Medical Society

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