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1.
IEEE Trans Med Imaging ; 42(11): 3436-3450, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37342953

RESUMO

This article describes a novel system for quantitative and volumetric measurement of tissue elasticity in the prostate using simultaneous multi-frequency tissue excitation. Elasticity is computed by using a local frequency estimator to measure the three-dimensional local wavelengths of steady-state shear waves within the prostate gland. The shear wave is created using a mechanical voice coil shaker which transmits simultaneous multi-frequency vibrations transperineally. Radio frequency data is streamed directly from a BK Medical 8848 transrectal ultrasound transducer to an external computer where tissue displacement due to the excitation is measured using a speckle tracking algorithm. Bandpass sampling is used that eliminates the need for an ultra-fast frame rate to track the tissue motion and allows for accurate reconstruction at a sampling frequency that is below the Nyquist rate. A roll motor with computer control is used to rotate the transducer and obtain 3D data. Two commercially available phantoms were used to validate both the accuracy of the elasticity measurements as well as the functional feasibility of using the system for in vivo prostate imaging. The phantom measurements were compared with 3D Magnetic Resonance Elastography (MRE), where a high correlation of 96% was achieved. In addition, the system has been used in two separate clinical studies as a method for cancer identification. Qualitative and quantitative results of 11 patients from these clinical studies are presented here. Furthermore, an AUC of 0.87±0.12 was achieved for malignant vs. benign classification using a binary support vector machine classifier trained with data from the latest clinical study with leave one patient out cross-validation.


Assuntos
Técnicas de Imagem por Elasticidade , Masculino , Humanos , Técnicas de Imagem por Elasticidade/métodos , Próstata/diagnóstico por imagem , Ultrassonografia , Elasticidade , Vibração , Imagens de Fantasmas
2.
Int J Radiat Oncol Biol Phys ; 115(5): 1061-1070, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36528488

RESUMO

PURPOSE: Using the primary endpoint of time to biochemical progression (TTP), Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy (ASCENDE-RT) randomized National Comprehensive Cancer Network patients with intermediate and high-risk prostate cancer to low-dose-rate brachytherapy boost (LDR-PB) or dose-escalated external beam boost (DE-EBRT). Randomization to the LDR-PB arm resulted in a 2-fold reduction in biochemical progression compared with the DE-EBRT group at a median follow-up of 6.5 years (P < .001). Herein, the primary endpoint and secondary survival endpoints of the ASCENDE-RT trial are updated at a 10-year median follow-up. METHODS: Patients were randomly assigned to either the LDR-PB or the DE-EBRT arm (1:1). All patients received 1 year of androgen deprivation therapy and 46 Gy in 23 fractions of pelvic RT. Patients in the DE-EBRT arm received an additional 32 Gy in 16 fractions, and those in the LDR-PB arm received an 125I implant prescribed to a minimum peripheral dose of 115 Gy. Two hundred patients were randomized to the DE-EBRT arm and 198 to the LDR-PB arm. RESULTS: The 10-year Kaplan-Meier TTP estimate was 85% ± 5% for LDR-PB compared with 67% ± 7% for DE-EBRT (log rank P < .001). Ten-year time to distant metastasis (DM) was 88% ± 5% for the LDR-PB arm and 86% ± 6% for the DE-EBRT arm (P = .56). There were 117 (29%) deaths. Ten-year overall survival (OS) estimates were 80% ± 6% for the LDR-PB arm and 75% ± 7% for the DE-EBRT arm (P = .51). There were 30 (8%) patients who died of prostate cancer: 12 (6%) in the LDR-PB arm, including 2 treatment-related deaths, and 18 (9%) in the DE-EBRT arm. CONCLUSIONS: Men randomized to the LDR-PB boost arm of the ASCENDE-RT trial continue to experience a large advantage in TTP compared with those randomized to the DE-EBRT arm. ASCENDE-RT was not powered to detect differences in its secondary survival endpoints (OS, DM, and time to prostate cancer-specific death) and none are apparent.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Antagonistas de Androgênios/uso terapêutico , Androgênios , Pelve , Estimativa de Kaplan-Meier , Braquiterapia/métodos
3.
Brachytherapy ; 21(5): 605-616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35729030

RESUMO

PURPOSE: To evaluate the outcomes of unfavorable intermediate-risk (UIR) and high-risk (HR) prostate cancer patients treated with combined external beam radiation therapy (EBRT) and low-dose-rate prostate brachytherapy (LDR-PB). METHODS AND MATERIALS: A population-based cohort of 568 prostate cancer patients treated with combined EBRT and LDR-PB from 2010 to 2016 was analyzed. All patients received EBRT followed by LDR-PB boost. Outcomes were compared with the results for the brachytherapy arm of the ASCENDE-RT trial. RESULTS: The median followup was 4.5 years. Sixty-nine percent (N = 391) had HR disease. Ninety-four percent of the HR and 57% of UIR were treated with androgen deprivation therapy (ADT) with a median duration of 12 months. The 5-year K-M biochemical progression-free survival (b-PFS), metastasis-free survival (MFS), and overall survival (OS) were 84 ± 2%, 90 ± 2%, and 88 ± 2%, similar to 89 ± 5%, 94 ± 4%, and 92 ± 4% for the ASCENDE-RT LDR-PB arm. The likelihood of achieving a PSA ≤0.2 ng/mL at 4 years was 88%, similar to 86% in the ASCENDE-RT LDR-PB arm. Thirty-three men (5.8%) would have been ineligible for ASCENDE-RT due to high-risk features. The 5-year K-M b-PFS, MFS and OS estimates were 86 ± 2%, 92 ± 1% and 89 ± 2% for the ASCENDE-RT eligible versus 56 ± 10% (p < 0.001), 73 ± 8% (p < 0.001), and 77 ± 9% (p = 0.098) for the ineligible patients. CONCLUSIONS: In this population-based cohort, combining LDR-PB with pelvic EBRT (+/- ADT) achieves very favorable b-PFS that compares to the LDR-PB arm of the ASCENDE-RT, supporting the generalizability of those results. Men ineligible for ASCENDE-RT, based on prognostic features, have a much higher risk of biochemical recurrence and metastatic relapse.


Assuntos
Braquiterapia , Neoplasias da Próstata , Antagonistas de Androgênios/uso terapêutico , Braquiterapia/métodos , Humanos , Masculino , Recidiva Local de Neoplasia/etiologia , Antígeno Prostático Específico , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Estudos Retrospectivos
4.
Int J Comput Assist Radiol Surg ; 17(5): 929-936, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35380340

RESUMO

PURPOSE: Pathology from trans-perineal template mapping biopsy (TTMB) can be used as labels to train prostate cancer classifiers. In this work, we propose a framework to register TTMB cores to advanced volumetric ultrasound data such as multi-parametric transrectal ultrasound (mpTRUS). METHODS: The framework has mainly two steps. First, needle trajectories are calculated with respect to the needle guiding template-considering deflections in their paths. In standard TTMB, a sparsely sampled ultrasound volume is taken prior to the procedure which contains the template overlaid on top of it. The position of this template is detected automatically, and the cores are mapped following the calculated needle trajectories. Second, the TTMB volume is aligned to the mpTRUS volume by a two-step registration method. Using the same transformations from the registration step, the cores are registered from the TTMB volume to the mpTRUS volume. RESULTS: TTMB and mpTRUS of 10 patients were available for this work. The target registration errors (TRE) of the volumes using landmarks picked by three research assistants (RA) and one radiation oncologist (RO) were on average 1.32 ± 0.7 mm and 1.03 ± 0.6 mm, respectively. Additionally, on average, our framework takes only 97 s to register the cores. CONCLUSION: Our proposed framework allows a quick way to find the spatial location of the cores with respect to volumetric ultrasound. Furthermore, knowing the correct location of the pathology will facilitate focal treatment and will aid in training imaging-based cancer classifiers.


Assuntos
Próstata , Neoplasias da Próstata , Biópsia , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Ultrassonografia
5.
Front Genet ; 12: 681768, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267781

RESUMO

Septoria nodorum blotch (SNB) is a necrotrophic disease of wheat prominent in some parts of the world, including Western Australia (WA) causing significant losses in grain yield. The genetic mechanisms for resistance are complex involving multiple quantitative trait loci. In order to decipher comparable or independent regulation, this study identified the genetic control for glume compared to foliar resistance across four environments in WA against 37 different isolates. High proportion of the phenotypic variation across environments was contributed by genotype (84.0% for glume response and 82.7% for foliar response) with genotype-by-environment interactions accounting for a proportion of the variation for both glume and foliar response (14.7 and 16.2%, respectively). Despite high phenotypic correlation across environments, most of the eight and 14 QTL detected for glume and foliar resistance using genome wide association analysis (GWAS), respectively, were identified as environment-specific. QTL for glume and foliar resistance neither co-located nor were in LD in any particular environment indicating autonomous genetic mechanisms control SNB response in adult plants, regulated by independent biological mechanisms and influenced by significant genotype-by- environment interactions. Known Snn and Tsn loci and QTL were compared with 22 environment-specific QTL. None of the eight QTL for glume or the 14 for foliar response were co-located or in linkage disequilibrium with Snn and only one foliar QTL was in LD with Tsn loci on the physical map. Therefore, glume and foliar response to SNB in wheat is regulated by multiple environment-specific loci which function independently, with limited influence of known NE-Snn interactions for disease progression in Western Australian environments. Breeding for stable resistance would consequently rely on recurrent phenotypic selection to capture and retain favorable alleles for both glume and foliar resistance relevant to a particular environment.

6.
Front Plant Sci ; 11: 771, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655592

RESUMO

The slow rate of genetic gain for improving resistance to Septoria nodorum blotch (SNB) is due to the inherent complex interactions between host, isolates, and environments. Breeding for improved SNB resistance requires evaluation and selection of wheat genotypes consistently expressing low SNB response in different target production environments. The study focused on evaluating 232 genotypes from global origins for resistance to SNB in the flag leaf expressed in different Western Australian environments. The aim was to identify resistant donor germplasm against historical and contemporary pathogen isolates and enhance our knowledge of the genetic basis of genotype-by-environment interactions for SNB response. Australian wheat varieties, inbred lines from Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), and International Center for Agricultural Research in the Dry Areas (ICARDA), and landraces from discrete regions of the world showed low to moderate phenotypic correlation for disease response amongst genotypes when evaluated with historical and contemporary isolates at two locations across 3 years in Western Australia (WA). Significant (P < 0.001) genotype-by-environment interactions were detected regardless of same or different isolates used as an inoculum source. Joint regression analysis identified 19 genotypes that consistently expressed low disease severity under infection with different isolates in multi-locations. The CIMMYT inbred lines, 30ZJN09 and ZJN12 Qno25, were particularly pertinent as they had low SNB response and highest trait stability at two locations across 3 years. Genome wide association studies detected 20 QTL associated with SNB resistance on chromosomes 1A, 1B, 4B, 5A, 5B, 6A, 7A, 7B, and 7D. QTL on chromosomes 1B and 5B were previously reported in similar genomic regions. Multiple QTL were identified on 1B, 5B, 6A, and 5A and detected in response to SNB infection against different isolates and specific environments. Known SnTox-Snn interactions were either not evident or variable across WA environments and SNB response may involve other multiple complex biological mechanisms.

7.
Brachytherapy ; 19(5): 589-598, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32682777

RESUMO

PURPOSE: The purpose of the study was to assess the feasibility of performing intraoperative dosimetry for permanent prostate brachytherapy by combining transrectal ultrasound (TRUS) and fluoroscopy/cone beam CT [CBCT] images and accounting for the effect of prostate deformation. METHODS AND MATERIALS: 13 patients underwent TRUS and multiview two-dimensional fluoroscopic imaging partway through the implant, as well as repeat fluoroscopic imaging with the TRUS probe inserted and retracted, and finally three-dimensional CBCT imaging at the end of the implant. The locations of all the implanted seeds were obtained from the fluoroscopy/CBCT images and were registered to prostate contours delineated on the TRUS images based on a common subset of seeds identified on both image sets. Prostate contours were also deformed, using a finite-element model, to take into account the effect of the TRUS probe pressure. Prostate dosimetry parameters were obtained for fluoroscopic and CBCT-dosimetry approaches and compared with the standard-of-care Day-0 postimplant CT dosimetry. RESULTS: High linear correlation (R2 > 0.8) was observed in the measured values of prostate D90%, V100%, and V150%, between the two intraoperative dosimetry approaches. The prostate D90% and V100% obtained from intraoperative dosimetry methods were in agreement with the postimplant CT dosimetry. Only the prostate V150% was on average 4.1% (p-value <0.05) higher in the CBCT-dosimetry approach and 6.7% (p-value <0.05) higher in postimplant CT dosimetry compared with the fluoroscopic dosimetry approach. Deformation of the prostate by the ultrasound probe appeared to have a minimal effect on prostate dosimetry. CONCLUSIONS: The results of this study have shown that both of the proposed dosimetric evaluation approaches have potential for real-time intraoperative dosimetry.


Assuntos
Braquiterapia/métodos , Fluoroscopia/métodos , Neoplasias da Próstata/radioterapia , Radiometria/métodos , Ultrassonografia/métodos , Tomografia Computadorizada de Feixe Cônico , Estudos de Viabilidade , Humanos , Cuidados Intraoperatórios , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
8.
Radiother Oncol ; 149: 64-69, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32442822

RESUMO

BACKGROUND AND PURPOSE: To identify a PSA threshold value at an intermediate follow-up time after low dose rate (LDR) prostate brachytherapy associated with cure, defined as long-term (10-15 year) freedom from prostate cancer. MATERIALS AND METHODS: Data from 7 institutions for 14,220 patients with localized prostate cancer treated with LDR brachytherapy, either alone (8552) or with external beam radiotherapy (n = 1175), androgen deprivation (n = 3165), or both (n = 1328), were analyzed. Risk distribution was 42.4% favorable, 49.2% intermediate, and 8.4% high-risk. Patients with clinical failure before 3.5 years were excluded. Kaplan-Meier analysis was used with clinical failure (local, distant, regional or biochemical triggering salvage) as an endpoint for each of four PSA categories: PSA ≤ 0.2, >0.2 to ≤0.5, >0.5 to ≤1.0, and >1.0 ng/mL. PSA levels at 4 years (±6 months) in 8746 patients without clinical failure were correlated with disease status at 10-15 years. RESULTS: For the 77.1% of patients with 4-year PSA ≤ 0.2, the freedom-from-recurrence (FFR) rates were 98.7% (95% CI 98.3-99.0) at 10 years and 96.1% (95% CI 94.8-97.2) at 15 years. Three independent validation cohorts confirmed 97-99% 10-year FFR rates with 4-year PSA ≤ 0.2. Successive PSA categories were associated with diminished disease-free rates at 10 and 15 years. PSA category was strongly associated with treatment success (p < 0.0005). CONCLUSIONS: Since 98.7% of patients with PSA ≤ 0.2 ng/mL at 4 years after LDR prostate brachytherapy were disease-free beyond 10 years, we suggest adopting this biochemical definition of cure for patients with ≥4 years' follow-up after LDR brachytherapy.


Assuntos
Braquiterapia , Neoplasias da Próstata , Antagonistas de Androgênios , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia , Antígeno Prostático Específico , Neoplasias da Próstata/radioterapia
9.
Brachytherapy ; 17(6): 837-844, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30245169

RESUMO

PURPOSE: To compare biochemical failure using a prostate-specific antigen (PSA) threshold of >0.2 ng/mL to that using Phoenix threshold (nadir+2 ng/mL). METHODS AND MATERIALS: Androgen suppression combined with elective nodal and dose-escalated radiation therapy (the ASCENDE-RT trial) is a randomized control trial in which 276 high-risk and 122 intermediate-risk patients were randomized to (1) a standard arm with 12 months of androgen deprivation therapy, pelvic external beam radiation therapy (EBRT) to 46 Gy, and an EBRT boost (dose-escalated EBRT [DE-EBRT]) to 78 Gy, or (2) an experimental arm which substituted a low-dose-rate prostate brachytherapy boost (LDR-PB). The primary endpoint was biochemical progression-free survival (b-PFS) using the Phoenix threshold. In this reanalysis of ASCENDE-RT, the b-PFS using phoenix is compared to the surgical PSA threshold of >0.2 ng/mL. RESULTS: Compared to nadir+2 ng/mL, the >0.2 ng/mL PSA threshold doubled the number of relapse events from 69 to 139. However, the increase was confined to the DE-EBRT subjects. The 7-year Kaplan-Meier b-PFS after DE-EBRT declined from 76% using nadir+2 ng/mL to 38% using the >0.2 ng/mL threshold (p < 0.001). Among the LDR-PB subset, there was no significant difference in b-PFS; the 7-year Kaplan-Meier b-PFS was 85% (>0.2 ng/mL) versus 88% (nadir+2 ng/mL) (p = 0.319). CONCLUSIONS: Replacing Phoenix with a surgical threshold greatly increased biochemical failure after DE-EBRT boost but had no effect after LDR-PB. As a result of this finding, PSA outcomes after surgery or brachytherapy can be directly compared by using the surgical definition of PSA failure. In this context, a brachytherapy boost appears to produce superior b-PFS compared to contemporary surgical series.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Braquiterapia/métodos , Antígeno Prostático Específico/análise , Neoplasias da Próstata/radioterapia , Idoso , Braquiterapia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Dosagem Radioterapêutica , Análise de Sobrevida , Falha de Tratamento
10.
Race Soc Probl ; 10(2): 79-90, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33281994

RESUMO

Concerns have been raised that the increase in popular interest in genetics may herald a new era within which racial inequities are seen as 'natural' or immutable. In the following study, we provide data from a nationally representative survey on how the US population perceives general ability, athleticism, and intellect being determined by race and/or genetics and whether they believe racial health inequities to be primarily the product of genetic or social factors. We find that self-described race is of primary importance in attributing general ability to race, increasing age is a significant factor in attributing athleticism and intellect to genes and race, and education is a significant factor in decreasing such racially and genetically deterministic views . Beliefs about the meaning of race are statistically significantly associated with respect to the perception of athletic abilities and marginally associated with the perception of racial health inequalities being either socially or genetically derived. Race, education, socioeconomic status, and concepts of race were frequently found to be multiplicative in their statistical effects. The persistent acceptance of a genetically and racially deterministic view of athleticism among the White and older population group is discussed in respect to its social impact, as is the high level of agreement that general abilities are determined by race among non-White respondents and those of lower socioeconomic status. We argue that these findings highlight that both biological and non-biological forms of understanding race continue to play a role into the politics of race and social difference within contemporary US society.

11.
Int J Radiat Oncol Biol Phys ; 100(1): 45-52, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29029889

RESUMO

PURPOSE: To determine whether the use of 6 months' adjuvant androgen deprivation therapy (ADT) combined with brachytherapy for intermediate-risk (IR) and low-risk (LR) prostate cancer is associated with an increased risk of cardiovascular death. METHODS AND MATERIALS: This is a retrospective analysis of prospectively collected data from men treated in the British Columbia Cancer Agency brachytherapy program from 1998 to 2012. Men were categorized by risk group and ADT use. Cardiac and other comorbidities were recorded and compared between groups. Biochemical control (Phoenix definition, nadir + 2 ng/mL) was ascertained. Overall, prostate, cardiac, and other-cause mortality were analyzed by the Kaplan-Meier method and Fine and Gray competing-risk analysis. RESULTS: The study included 3155 men (1142 with LR cancer and 2013 with IR cancer) who have been followed up for a median of 7.9 years. ADT was received by 47% of IR patients and 37% of LR patients for a median of 6 months. Men with IR cancer were older and had more cardiac and other comorbidities than LR cases (P<.01). Biochemical control improved from 86% to 89% at 10 years with the use of ADT (P=.006). Overall survival was inferior in patients receiving ADT (84% vs 86% at 10 years, P=.0274), and on competing-risk analysis, cardiovascular mortality in patients receiving ADT was higher in IR cases, 5.2% versus 3.6% at 10 years (P=.0493), but not in LR cases. Multivariate analysis confirmed increased cardiac mortality in IR patients receiving ADT (hazard ratio, 1.95 [95% confidence interval, 1.15-3.34]; P=.014). CONCLUSIONS: ADT adds little meaningful benefit in terms of biochemical control for IR men treated with low-dose-rate brachytherapy but likely decreases overall survival because of increased cardiac mortality. IR patients were older and had more cardiac risk factors than LR prostate cases; this may be because of a screening effect, case selection, or common etiologic cause.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Braquiterapia , Doenças Cardiovasculares/mortalidade , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Distribuição de Qui-Quadrado , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas
12.
Brachytherapy ; 16(6): 1101-1105, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29032014

RESUMO

PURPOSE: To describe outcomes of men with unfavorable (high-tier) intermediate risk prostate cancer (H-IR) treated with low-dose-rate (LDR) brachytherapy, with or without 6 months of androgen deprivation therapy (ADT). METHODS AND MATERIALS: Patients with H-IR prostate cancer, treated before 2012 with LDR brachytherapy without external radiation are included. Baseline tumor characteristics are described. Outcomes between groups receiving ADT are measured by Phoenix (nadir +2 ng/mL), and threshold 0.4 ng/mL biochemical relapse definitions (bNEDs), as well as clinical end points. Standard descriptive and actuarial statistics are used. RESULTS: Two hundred sixty men were eligible, 139 (53%) did not receive ADT and 121 (47%) did. Median follow-up was 5 years. Men treated with ADT had higher T stage and percent positive cores but lower pathologic grade group. bNED rates with and without ADT at 5 years are 86% and 85% (p = 0.52) with the Phoenix definition, and 83% and 78% (p = 0.13) with the threshold definition. Local recurrence or metastasis were rare in both groups (<5%, p = not significant). Death from prostate cancer only occurred in 4 patients, 2 in each group. Overall survival was 85% in those treated with ADT and 93% without at 8 years, p = 0.15. CONCLUSIONS: The addition of 6 months of ADT to LDR brachytherapy for H-IR prostate cancer does not improve 5 year prostate specific antigen control, and we no longer routinely recommended it.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/tratamento farmacológico , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Resultado do Tratamento
14.
J Contemp Brachytherapy ; 9(3): 197-208, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28725242

RESUMO

PURPOSE: To evaluate the feasibility and to report the early outcomes of focal treatment of prostate cancer using low-dose-rate brachytherapy (LDR-PB). MATERIAL AND METHODS: Seventeen patients were screened with multi-parametric magnetic resonance imaging (mpMRI), 14 of whom proceeded to receive trans-perineal template mapping biopsy (TTMB). Focal LDR-PB was performed on five eligible patients using dual air kerma strength treatment plans based on planning target volumes derived from cancer locations and determined by TTMB. Patient follow-up includes prostate specific antigen (PSA) measurements, urinary and sexual function questionnaires, repeated imaging and TTMB at specific intervals post-treatment. RESULTS: Feasibility of focal LDR-PB was shown and short-term outcomes are promising. While the detection rate of tumors, a majority of which were low grade GS 3 + 3, was found to be low on mpMRI (sensitivity of 37.5%), our results suggest the potential of mpMRI in detecting the presence of higher grade (GS ≥ 3 + 4), and bilateral disease indicating its usefulness as a screening tool for focal LDR-PB. CONCLUSIONS: Low-dose-rate brachytherapy is a favorable ablation option for focal treatment of prostate cancer, requiring minimal modification to the standard (whole gland) LDR-PB treatment, and appears to have a more favorable side effect profile. Further investigation, in the form of a larger study, is needed to assess the methods used and the long-term outcomes of focal LDR-PB.

15.
Clin Oncol (R Coll Radiol) ; 29(10): 696-701, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28712786

RESUMO

AIMS: This study describes the proportion of men who experienced hot flashes (flashes), and the testosterone level at onset, peak frequency and cessation of flashes after 12 months of androgen deprivation therapy (ADT) in men undergoing curative-intent external beam radiation therapy (± brachytherapy boost). We also aimed to characterise testosterone recovery in this population. MATERIALS AND METHODS: This was a pre-specified secondary analysis of the ASCENDE-RT clinical trial. Three hundred and ninety-eight men were randomised. All received 12 months of ADT. The presence and frequency of flashes were patient reported. Cessation of flashes was defined as the first date a patient reported resolution of this symptom. Testosterone recovery was defined as any single serum testosterone above the threshold of 5, 7.5 or 10 nmol/l. RESULTS: The median age and follow-up were 68 years and 6.1 years. Flashes were reported in 93% of men. Flashes began and reached peak frequency at a median time of 4.0 months from the first luteinizing hormone-releasing hormone injection when testosterone levels had fallen to castrate. The median time to cessation of flashes was 7.6 months after the cessation of ADT (last injection + 3 months), when the median testosterone had risen to 5.7 nmol/l. A resolution of flashes was reported in 99% of patients. Baseline testosterone was available in 338 patients (85%). The median baseline testosterone was 13.2 nmol/l. The median (95% confidence interval) time of testosterone recovery to thresholds of 5 nmol/l, 7.5 nmol/l and 10 nmol/l were 9 (9-10) months, 13 (10-15) months and 18 (17-19) months from the cessation of ADT. At the time of censor, 96, 94 and 91% of patients had recovered testosterone to thresholds of 5, 7.5 and 10 nmol/l. CONCLUSION: Flashes occur at castrate levels of testosterone, with cessation of hot flashes antedating full recovery of testosterone in most patients. Rates of testosterone recovery after 12 months of ADT exceed 90%, although it can be delayed.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Braquiterapia/métodos , Fogachos/induzido quimicamente , Neoplasias da Próstata , Testosterona/uso terapêutico , Idoso , Antagonistas de Androgênios/uso terapêutico , Humanos , Masculino , Neoplasias da Próstata/complicações , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Testosterona/sangue
16.
Regul Toxicol Pharmacol ; 89: 101-111, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28736287

RESUMO

Research conducted during past decades to reduce the level of the tobacco specific nitrosamine N-nitrosonornicotine (NNN) and its precursor nornicotine in tobacco yielded identification of three tobacco genes encoding for cytochrome P450 nicotine demethylases converting nicotine to nornicotine. We carried out trials to investigate the effect of using tobaccos containing three non-functional nicotine demethylase genes on the selective reduction of NNN in cigarette tobacco filler and mainstream smoke. Our results indicate that the presence of non-functional alleles of the three genes reduces the level of nornicotine and NNN in Burley tobacco by 70% compared to the level observed in currently available low converter (LC) Burley tobacco varieties. The new technology, named ZYVERT™, does not require a regular screening process, while a yearly selection process is needed to produce LC Burley tobacco seeds for NNN reduction. The reduction of NNN observed in smoke of blended prototype cigarettes is proportional to the inclusion level of tobacco having ZYVERT™ technology. Inclusion of Burley tobacco possessing the new trait into a typical American blend resulted in a selective reduction of NNN in cigarette smoke, while the levels of other Harmful and Potentially Harmful Constituents (HPHC) currently in the abbreviated list provided by the US Food and Drug Administration are statistically equivalent in comparison with the levels obtained in reference prototype cigarettes containing LC Burley.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Nicotiana/química , Nicotiana/genética , Nicotina/metabolismo , Nitrosaminas/metabolismo , Fumaça/análise , Alelos , Nicotina/genética , Sementes/química , Produtos do Tabaco/análise
17.
Int J Radiat Oncol Biol Phys ; 98(3): 581-589, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28581398

RESUMO

PURPOSE: To report the patient-reported health-related quality of life (HR-QoL) outcomes for a multicenter randomized trial evaluating the safety and efficacy of 2 different techniques for dose escalation. METHODS AND MATERIALS: A total of 357 men with intermediate- and high-risk prostate cancer were stratified by risk group and randomized (1:1) to either a dose-escalated external beam (DE-EBRT) boost (n=177) or a low-dose-rate prostate brachytherapy (LDR-PB) boost (n=180) as part of combined modality therapy. The HR-QoL was assessed using the SF36v2 questionnaire, with additional scales for urinary, bowel, and sexual function. Date of starting androgen deprivation therapy was considered time zero, the median follow-up of 6 years. Scales were scored from 0 to 100; a decline in a mean score ≥10 compared with baseline was considered a clinically significant decline. This was an intent-to-treat analysis. RESULTS: Mean domain scores at baseline were well balanced between the 2 treatment arms. A clinically significant decline in mean scores in both the arms compared with baseline was noted for role physical (DE-EBRT [-11.4] and LDR-PB [-15.3]) and sexual function scale (DE-EBRT [-15.1] and LDR-PB [-19.2]). There was a significantly larger drop in mean scores in the LDR-PB group compared with the DE-EBRT group for physical function (-15.3 vs -6.9; P=.03), urinary function (-3.6 vs -0.5; P=.04). CONCLUSION: At 6 years' follow up, there were no significant differences in mean scores in 9 of 11 scales compared with baseline in both arms. A clinically significant decline in mean scores was noted in both arms for role physical and sexual function scales. There was a statistically significant decline in physical function and urinary function scales in the LDR-PB arm compared with the DE-EBRT arm.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Reirradiação/métodos , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Estudos de Viabilidade , Flutamida/administração & dosagem , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/tratamento farmacológico , Risco , Comportamento Sexual , Inquéritos e Questionários , Fatores de Tempo , Transtornos Urinários/etiologia
18.
Int J Radiat Oncol Biol Phys ; 98(2): 482, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28463169
19.
Int J Radiat Oncol Biol Phys ; 98(2): 286-295, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28433432

RESUMO

PURPOSE: To report the genitourinary (GU) and gastrointestinal (GI) morbidity and erectile dysfunction in a randomized trial comparing 2 methods of dose escalation for high- and intermediate-risk prostate cancer. METHODS AND MATERIALS: ASCENDE-RT (Androgen Suppression Combined with Elective Nodal and Dose Escalated Radiation Therapy) enrolled 398 men, median age 68 years, who were then randomized to either a standard arm that included 12 months of androgen deprivation therapy and pelvic irradiation to 46 Gy followed by a dose-escalated external beam radiation therapy (DE-EBRT) boost to 78 Gy, or an experimental arm that substituted a low-dose-rate prostate brachytherapy (LDR-PB) boost. At clinic visits, investigators recorded GU and GI morbidity and information on urinary continence, catheter use, and erectile function. Exclusion of 15 who received nonprotocol treatment and correction of 14 crossover events left 195 men who actually received a DE-EBRT boost and 188, an LDR-PB boost. Median follow-up was 6.5 years. RESULTS: The LDR-PB boost increased the risk of needing temporary catheterization and/or requiring incontinence pads. At 5 years the cumulative incidence of grade 3 GU events was 18.4% for LDR-PB, versus 5.2% for DE-EBRT (P<.001). Compared with the cumulative incidence, the 5-year prevalence of grade 3 GU morbidity was substantially lower for both arms (8.6% vs 2.2%, P=.058). The 5-year cumulative incidence of grade 3 GI events was 8.1% for LDR-PB, versus 3.2% for DE-EBRT (P=.124). The 5-year prevalence of grade 3 GI toxicity was lower than the cumulative incidence for both arms (1.0% vs 2.2%, respectively). Among men reporting adequate baseline erections, 45% of LDR-PB patients reported similar erectile function at 5 years, versus 37% after DE-EBRT (P=.30). CONCLUSIONS: The incidence of acute and late GU morbidity was higher after LDR-PB boost, and there was a nonsignificant trend for worse GI morbidity. No differences in the frequency of erectile dysfunction were observed.


Assuntos
Braquiterapia/efeitos adversos , Disfunção Erétil/etiologia , Incontinência Fecal/etiologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/efeitos adversos , Transtornos Urinários/etiologia , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/efeitos adversos , Antagonistas de Androgênios/uso terapêutico , Braquiterapia/métodos , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Diarreia/epidemiologia , Diarreia/etiologia , Intervalo Livre de Doença , Disfunção Erétil/epidemiologia , Estudos de Viabilidade , Incontinência Fecal/epidemiologia , Seguimentos , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etiologia , Hormônio Liberador de Gonadotropina/efeitos adversos , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Incidência , Análise de Intenção de Tratamento , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pelve , Dosagem Radioterapêutica , Reirradiação/efeitos adversos , Reirradiação/métodos , Reto/efeitos da radiação , Fatores de Tempo , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Transtornos Urinários/epidemiologia , Sistema Urogenital/efeitos da radiação
20.
J Empir Res Hum Res Ethics ; 12(3): 169-179, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28434393

RESUMO

Conducting genetics-related research with populations that have historically experienced considerable harm and little benefit from genetics research poses unique challenges for understanding community-based perceptions of new genetic technologies. This article identifies challenges and strategies for collecting qualitative data on the perceptions of direct-to-consumer (DTC) Genetic Ancestry tests (GAT) among diverse Indigenous communities. Based on a 3-year project related to perceptions, attitudes, and values associated with genetic ancestry testing among diverse Indigenous communities in Oklahoma, the engagement process revealed specific opportunities to improve the process of qualitative data collection related to GAT, and more broadly, to conduct genetics-related research with Indigenous communities in culturally and methodologically appropriate ways. Priority areas include issues related to participant recruitment and tribal advisory boards, challenges of self-identification as a recruitment mechanism, and the necessity of including Indigenous researchers in all aspects of the research process.


Assuntos
Atitude Frente a Saúde , Pesquisa Participativa Baseada na Comunidade , Competência Cultural , Pesquisa em Genética , Testes Genéticos , Indígenas Norte-Americanos , Características de Residência , Comitês Consultivos , Cultura , Feminino , Humanos , Masculino , Oklahoma , Pesquisa Qualitativa , Pesquisadores , Valores Sociais
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