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1.
Phys Rev Lett ; 131(16): 168101, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925715

RESUMEN

Recent experiments on weak polyelectrolyte brushes found marked shifts in the effective pK_{a} that are linear in the logarithm of the salt concentration. Comparing explicit-particle simulations with mean-field calculations we show that for high grafting densities the salt concentration effect can be explained using the ideal Donnan theory, but for low grafting densities the full shift is due to a combination of the Donnan effect and the polyelectrolyte effect. The latter originates from electrostatic correlations that are neglected in the Donnan picture and that are only approximately included in the mean-field theory. Moreover, we demonstrate that the magnitude of the polyelectrolyte effect is almost invariant with respect to salt concentration but depends on the grafting density of the brush. This invariance is due to a complex cancellation of multiple effects. Based on our results, we show how the experimentally determined pK_{a} shifts may be used to infer the grafting density of brushes, a parameter that is difficult to measure directly.

2.
J Chem Phys ; 159(1)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37417757

RESUMEN

We introduce a Monte-Carlo method that allows for the simulation of a polymeric phase containing a weak polyelectrolyte, which is coupled to a reservoir at a fixed pH, salt concentration, and total concentration of a weak polyprotic acid. The method generalizes the established grand-reaction method by Landsgesell et al. [Macromolecules 53, 3007-3020 (2020)] and, thus, allows for the simulation of polyelectrolyte systems coupled to reservoirs with a more complex chemical composition. In order to set the required input parameters that correspond to a desired reservoir composition, we propose a generalization of the recently published chemical potential tuning algorithm of Miles et al. [Phys. Rev. E 105, 045311 (2022)]. To test the proposed tuning procedure, we perform extensive numerical tests for both ideal and interacting systems. Finally, as a showcase, we apply the method to a simple test system that consists of a weak polybase solution that is coupled to a reservoir containing a small diprotic acid. The complex interplay of the ionization of various species, the electrostatic interactions, and the partitioning of small ions leads to a non-monotonous, stepwise swelling behavior of the weak polybase chains.


Asunto(s)
Polímeros , Cloruro de Sodio , Polielectrolitos , Iones , Simulación por Computador , Polímeros/química
3.
J Clin Oncol ; 41(24): 4035-4044, 2023 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-37315297

RESUMEN

PURPOSE: To determine whether addition of external beam radiation therapy (EBRT) to brachytherapy (BT) (COMBO) compared with BT alone would improve 5-year freedom from progression (FFP) in intermediate-risk prostate cancer. METHODS: Men with prostate cancer stage cT1c-T2bN0M0, Gleason Score (GS) 2-6 and prostate-specific antigen (PSA) 10-20 or GS 7, and PSA < 10 were eligible. The COMBO arm was EBRT (45 Gy in 25 fractions) to prostate and seminal vesicles followed by BT prostate boost (110 Gy if 125-Iodine, 100 Gy if 103-Pd). BT arm was delivered to prostate only (145 Gy if 125-Iodine, 125 Gy if 103-Pd). The primary end point was FFP: PSA failure (American Society for Therapeutic Radiology and Oncology [ASTRO] or Phoenix definitions), local failure, distant failure, or death. RESULTS: Five hundred eighty-eight men were randomly assigned; 579 were eligible: 287 and 292 in COMBO and BT arms, respectively. The median age was 67 years; 89.1% had PSA < 10 ng/mL, 89.1% had GS 7, and 66.7% had T1 disease. There were no differences in FFP. The 5-year FFP-ASTRO was 85.6% (95% CI, 81.4 to 89.7) with COMBO compared with 82.7% (95% CI, 78.3 to 87.1) with BT (odds ratio [OR], 0.80; 95% CI, 0.51 to 1.26; Greenwood T P = .18). The 5-year FFP-Phoenix was 88.0% (95% CI, 84.2 to 91.9) with COMBO compared with 85.5% (95% CI, 81.3 to 89.6) with BT (OR, 0.80; 95% CI, 0.49 to 1.30; Greenwood T P = .19). There were no differences in the rates of genitourinary (GU) or GI acute toxicities. The 5-year cumulative incidence for late GU/GI grade 2+ toxicity is 42.8% (95% CI, 37.0 to 48.6) for COMBO compared with 25.8% (95% CI, 20.9 to 31.0) for BT (P < .0001). The 5-year cumulative incidence for late GU/GI grade 3+ toxicity is 8.2% (95% CI, 5.4 to 11.8) compared with 3.8% (95% CI, 2.0 to 6.5; P = .006). CONCLUSION: Compared with BT, COMBO did not improve FFP for prostate cancer but caused greater toxicity. BT alone can be considered as a standard treatment for men with intermediate-risk prostate cancer.


Asunto(s)
Braquiterapia , Neoplasias de la Próstata , Braquiterapia/efectos adversos , Humanos , Neoplasias de la Próstata/radioterapia , Antígeno Prostático Específico , Dosificación Radioterapéutica , Resultado del Tratamiento , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años
4.
J Phys Chem B ; 127(25): 5601-5608, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37327109

RESUMEN

NMR relaxometry is a powerful and well-established experimental approach for characterizing dynamic processes in soft matter systems. All-atom (AA) resolved simulations are typically employed to gain further microscopic insights while reproducing the relaxation rates R1. However, such approaches are limited to time and length scales that prevent to model systems such as long polymer chains or hydrogels. Coarse graining (CG) can overcome this barrier at the cost of losing atomistic details that impede the calculation of NMR relaxation rates. Here, we address this issue by performing a systematic characterization of dipolar relaxation rates R1 on a PEG-H2O mixture at two different levels of details: AA and CG. Remarkably, we show that NMR relaxation rates R1 obtained at the CG level obey the same trends when compared to AA calculations but with a systematic offset. This offset is due to, on the one hand, the lack of an intramonomer component and, on the other hand, the inexact positioning of the spin carriers. We show that the offset can be corrected for quantitatively by reconstructing a posteriori the atomistic details for the CG trajectories.

5.
Soft Matter ; 19(19): 3522-3525, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37158282

RESUMEN

Levin and Bakhshandeh suggested in their comment that (1), we stated in our recent review that pH-pKA is a universal parameter for titrating systems, that (2), we omitted to mention in our review the broken symmetry of the constant pH algorithm, and that (3), a constant pH simulation must include a grand-canonical exchange of ions with the reservoir. As a reply to (1), we point out that Levin and Bakhshandeh misquoted and hence invalidated our original statement. We therefore explain in detail under which circumstances pH-pKA can be a universal parameter, and also demonstrate why their numerical example is not in contradiction to our statement. Moreover, the fact that pH-pKA is not a universal parameter for titrating systems is well known in the pertinent literature. Regarding (2), we admit that the symmetry-breaking feature of the constant pH algorithm has escaped our attention at the time of writing the review. We added some clarifying remarks to this behavior. Concerning (3), we point out that the grand-canonical coupling and the resultant Donnan potential are not features of single-phase systems, but are essential for two-phase systems, as was shown in a recent paper by some of us, see J. Landsgesell et al., Macromolecules, 2020, 53, 3007-3020.

6.
Int J Radiat Oncol Biol Phys ; 112(5): 1115-1122, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34740768

RESUMEN

PURPOSE: We report efficacy of a prospective phase 2 trial (NCT00450411) of salvage low-dose-rate (LDR) prostate brachytherapy (BT) for local failure (LF) after prior external beam radiation therapy (EBRT) with minimum 5-years' follow-up. METHODS AND MATERIALS: Eligible patients had low/intermediate risk prostate cancer (PCa) before EBRT and biopsy-proven LF >30 months after EBRT, with prostate-specific antigen <10 ng/mL and no regional/distant disease. The primary endpoint, late gastrointestinal and genitourinary adverse events (Common Terminology Criteria for Adverse Events v3.0) grade ≥3 were 14%. With minimum 5-year follow-up after salvage BT, secondary clinical outcomes including disease-free survival (DFS; includes death from any cause), disease-specific survival, and overall survival (OS) were estimated using the Kaplan-Meier method and modelled using Cox proportional hazards regression. Local tumor progression (ie, LF), distant failure (DF), and biochemical failure (BF) were estimated using cumulative incidence. Time to LF, DF, and BF were modeled by cause-specific Cox proportional hazards regression. RESULTS: From May 2007 to January 2014, 20 centers registered 100 patients (92 analyzable). Median follow-up is 6.7 years (range, 0.3-11.2); median age 70 years (range, 55-82); median prior EBRT dose 74 Gy [interquartile range (IQR):70 - 76] at a median of 85 months prior (IQR 60-119 months). Androgen deprivation was combined with salvage BT in 16%. Ten-year OS is 70% [95% confidence interval (CI) 58% - 83%]. Nineteen patients died (5 PCa, 10 other, 4 unknown). Ten-year failure rates are local 5% (95% CI, 1-11), distant 19% (95% CI, 10-29), and biochemical 46% (95% CI, 34-57). DFS is 61% at 5 years and 33% at 10 years. No baseline characteristic was significantly associated with any clinical outcome. CONCLUSIONS: This is the first prospective multicenter trial reporting outcomes of salvage LDR BT for LF after EBRT. Five-year freedom from BF is 68%, comparable to other salvage modalities. Although further LF is rare (5%), BF climbs to 46% by 10 years.


Asunto(s)
Braquiterapia , Neoplasias de la Próstata , Anciano , Anciano de 80 o más Años , Antagonistas de Andrógenos/uso terapéutico , Braquiterapia/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Próstata/patología , Antígeno Prostático Específico , Neoplasias de la Próstata/patología , Estudios Retrospectivos , Terapia Recuperativa
8.
J Clin Gastroenterol ; 55(9): 792-797, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32947375

RESUMEN

INTRODUCTION: Since 2001, device-assisted enteroscopy (DAE) has revolutionized the diagnostic and therapeutic capabilities for managing small bowel pathology. Though commonly performed, there have been no recent large studies to assess the use, yield, and risks of DAE and none that include all 3 DAE modalities. We hypothesized that DAE is safe with high diagnostic and therapeutic yields achieved within reasonable procedure duration and here we present a large retrospective multicenter US study evaluating the use, yield, and complications of DAE. METHODS: After obtaining institutional review board approval, electronic records were used to identify all DAE's performed for luminal small bowel evaluation in adult patients at 4 US referral centers (Duke University Medical Center, New York University Langone Medical Center, Louisiana State University Health Sciences Center, and University of Massachusetts Medical Center) from January 1, 2014 to January 1, 2019. Electronic medical records were reviewed to collect and analyze a variety of procedure-related outcomes. Using the data pooled across centers, descriptive statistics were generated for the patient and procedure-related characteristics and outcomes; relationships between characteristics and outcomes were explored. RESULTS: A total of 1787 DAE's were performed over this 5-year period (392 at Duke University Medical Center, 887 at Louisiana State University Health Sciences Center, 312 at New York University Langone Medical Center, and 195 at University of Massachusetts Medical Center). Of these, there were 1017 (57%) double-balloon, 391 (29%) single-balloon, and 378 (21%) spiral enteroscopies. The mean age of patients undergoing DAE was 66 years and 53% of examinations were performed on women; 18% of patients in the cohort underwent >1 DAE over this time span. A total of 53% of examinations were performed for suspected small bowel bleeding, 31% were directly guided by video capsule endoscopy findings and 8% were performed for abnormal imaging. A total of 85% of examinations used an antegrade approach and DAE took a mean of 45 minutes to complete; 76% of examinations revealed abnormal findings, with vascular, inflammatory, and neoplastic findings seen in 49%, 17%, and 15% of the cohort, respectively. Older age was significantly associated with any abnormal finding, including arteriovenous malformations (P<0.0001); 50% of examinations included a therapeutic maneuver, most commonly argon plasma coagulation/cautery (43%). There were complications in 16 examinations (0.9%) including 2 perforations (0.1%), 6 cases with bleeding (0.3%) and 1 episode of pancreatitis (0.1%). CONCLUSIONS: DAE is most commonly performed to evaluate suspected small bowel bleeding and is commonly directed by video capsule findings. DAE is safe, has a high diagnostic yield, with 76% of examinations showing abnormal findings, and frequently features therapeutic maneuvers. Advancing age is associated with abnormal findings on DAE.


Asunto(s)
Endoscopía Capsular , Enfermedades Intestinales , Adulto , Anciano , Enteroscopía de Doble Balón , Femenino , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Humanos , Enfermedades Intestinales/diagnóstico , Intestino Delgado/diagnóstico por imagen , Estudios Retrospectivos , Estados Unidos
9.
Pract Radiat Oncol ; 10(3): 186-194, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31978591

RESUMEN

PURPOSE: Previously a phase III trial of a hydrogel rectal spacer during prostate radiation therapy found decreased toxicity and a clinically significant improvement in bowel quality of life (QOL) at 3 years by the Expanded Prostate Cancer Index. We performed a secondary analysis to identify men less likely to benefit. METHODS AND MATERIALS: Clinical and dosimetric data for the 222 patients enrolled on the SpaceOAR phase III trial were analyzed. The volume of rectum treated to 70 Gy (V70) and the quantitative analysis of normal tissue effects in the clinic (QUANTEC) rectal dose goals were used as surrogates for clinical benefit and plan quality. Mean bowel QOL was assessed at 15 and 36 months posttreatment and the likelihood of 1× (5 points) or 2× (10 points) minimally important difference changes were assessed. RESULTS: Rectal V70 was correlated with physician scored toxicity (P = .033) and was used as a surrogate for plan quality. There was no correlation between prostate volume and rectal V70 (r = 0.077). Rectal V70 pre- and post-hydrogel was 13% and 3% for the smallest prostates (<40 mL) and 12% and 2% for the largest (>80 mL). The relative reduction in rectal V70 of 78% did not vary by prespacer V70, but the absolute reduction was greater for a higher V70. All spacer plans met the 5 QUANTEC rectal dose constraints, although 92% of control plans met all constraints. At 3 years, those not meeting all QUANTEC goals had a 15.0-point (standard deviation 15.1) decline, control patients meeting QUANTEC goals had a 4.0-point (9.5) decline, and spacer had >0.5 (7.6; P < .01). Previous surgery was not correlated with QOL (P = .8). Across prognostic groups, including age, body mass index, previous surgery, target volume, or quality of radiation plans, there was no statistically significant heterogeneity in the relative benefit of spacer in decreasing the risk of 1× or 2× the minimally important difference declines. CONCLUSIONS: There was little heterogeneity in the likelihood of spacer reducing the risk of declines in bowel QOL across clinical and dosimetric variables. Even for the >95% of plans meeting QUANTEC rectal criteria, hydrogel spacer provided potentially meaningful benefits.


Asunto(s)
Próstata/cirugía , Neoplasias de la Próstata/cirugía , Recto/cirugía , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Próstata/efectos de la radiación , Neoplasias de la Próstata/radioterapia , Recto/efectos de la radiación
11.
J Gastrointest Oncol ; 10(5): 928-934, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31602331

RESUMEN

BACKGROUND: Midgut neuroendocrine tumor (NET) patients are often diagnosed at advanced stages with extensive mesenteric nodal and hepatic metastasis. The only potentially curative treatment is surgical tumor eradication. Despite an aggressive resection, macro and microscopic residual disease still may remain in the resection bed. We hypothesize that the application of 5-fluorouracil (5-FU) within the tumor bed will help eliminate microscopic residual disease. METHODS: Records of 189 patients who underwent extensive cytoreductive surgeries during 2003-2012 for advanced, midgut NETs with extensive mesenteric lymphadenopathy were reviewed. Eighty-six patients (46%) who had 5-FU saturated gel foam strips secured into their mesenteric resection sites served as the study group and a matching 103 patients (54%) who did not have such an intra-operative chemotherapy served as controls. Survival from the time of diagnosis and post-operative complications between the two groups were compared. RESULTS: Mortality rates at 30, 60 and 90 days post-operatively were 4%, 0%, 0% versus 2%, 0%, 2% for study and control groups, respectively. Major complications (Grades III & IV) at the same intervals were 0, 0, 1 versus 2, 3, 2 for study and control groups, respectively. Median survival was 236 months versus 148 months for the study and control groups, respectively 24 (P=0.15). CONCLUSIONS: Intraoperative tumor resection bed chemotherapy is a safe adjuvant without discernible toxicity. This procedure may provide survival benefits to midgut NET patients with extensive mesenteric lymphadenopathy undergoing extensive cytoreductive surgery. Further study in prospective trials must be conducted to determine definitive benefit to the NET patient.

12.
Plant Dis ; 103(11): 2714-2732, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31560599

RESUMEN

Among the biotic constraints of common mushroom (Agaricus bisporus) production, bacterial blotch is considered the most important mushroom disease in terms of global prevalence and economic impact. Etiology and management of bacterial blotch has been a major concern since its original description in 1915. Although Pseudomonas tolaasii is thought to be the main causal agent, various Pseudomonas species, as well as organisms from other genera have been reported to cause blotch symptoms on mushroom caps. In this review, we provide an updated overview on the etiology, epidemiology, and management strategies of bacterial blotch disease. First, diversity of the causal agent(s) and utility of high throughput sequencing-based approaches in the precise characterization and identification of blotch pathogen(s) is explained. Further, due to the limited options for use of conventional pesticides in mushroom farms against blotch pathogen(s), we highlight the role of balanced threshold of relative humidity and temperature in mushroom farms to combat the disease in organic and conventional production. Additionally, we discuss the possibility of the use of biological control agents (either antagonistic mushroom-associated bacterial strains or bacteriophages) for blotch management as one of the sustainable approaches for 21st century agriculture. Finally, we aim to elucidate the association of mushroom microbiome in cap development and productivity on one hand, and blotch incidence/outbreaks on the other hand.


Asunto(s)
Agaricus , Microbiología de Alimentos , Pseudomonas , Microbiología de Alimentos/tendencias
13.
Can Urol Assoc J ; 13(12): 406-411, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31364974

RESUMEN

INTRODUCTION: Asymptomatic microscopic hematuria (AMH) is defined in the Canadian Urological Association (CUA) guideline as >2 red blood cells (RBCs) per high-powered field (HPF). Our objective was to evaluate guideline adherence for AMH at our center. Secondarily, we aimed to identify areas of the guideline that can be optimized. METHODS: We retrospectively reviewed 875 consecutive adults referred to two urologists for hematuria between June 2010 and June 2016. Patient characteristics, risk factors, and outcomes were added to an encrypted Research Electronic Data Capture (REDCap) database. Evaluation of microscopic hematuria reporting was performed by analyzing 681 urine samples reported as 1-5 RBC/HPF. Healthcare costs were obtained from Alberta Health Services (AHS), Data Integration and Management Repository (DIMR), and Alberta Society of Radiologists (ASR). RESULTS: Of the 875 patients referred with hematuria, 400 had AMH. Overall, 96.5% completed evaluation consistent with the CUA guideline. The incidence of pathology requiring surgical intervention was 21/400 (5%) with a 0.8% rate (3/400) of urothelial cell carcinoma (UCC) (non-invasive, low-grade). No malignancy was found in non-smokers with normal cytology, normal imaging and <50 RBC/HPF; 44% had AMH in the 1-5 RBCs/HPF range. Only 41% (279/681) of urine samples categorized as 1-5 RBCs/ HPF had guideline-defined microscopic hematuria. By changing local microscopic hematuria reporting to differentiate 1-2 and 3-5 RBCs/HPF, we estimate $745 000 in annual savings. CONCLUSIONS: At our center, CUA AMH guideline adherence is high. We did not find malignancy in non-smokers with normal cytology, imaging and <50 RBC/HPF. We identified and changed regional microscopic hematuria reporting to fit the CUA definition, eliminating unnecessary investigations and healthcare costs.

14.
Pancreas ; 48(3): 356-362, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30768573

RESUMEN

OBJECTIVES: Elevated pancreastatin (PST) levels have been shown to be associated with poor prognosis in small bowel neuroendocrine tumors (NETs). We hypothesized that plasma PST levels that remain elevated following surgical cytoreduction portend a poor prognosis in well-differentiated small bowel NETs. METHODS: Patients diagnosed with small bowel NETs who underwent surgical cytoreduction at our institution were identified. Demographics, histopathologic characteristics, and biochemical data were collected. Only patients who had serial preoperative PST (PreopPST) and postoperative PST (PostopPST) levels were included in this study. Patients were sorted into groups by PST level to assess their response to surgical cytoreduction (group 1, PreopPST/PostopPST normal; group 2, PreopPST elevated/PostopPST normal; group 3, PreopPST/PostopPST elevated). Survival rates were calculated from the date of surgery. RESULTS: PreopPST and PostopPST levels were collected from 300 patients. Patients in groups 1 (n = 74) and 2 (n = 81) had a significant survival advantage compared with patients in group 3 (n = 145) (P < 0.0001). Kaplan-Meier 5- and 10-year survival rates were as follows: group 1: 93% and 82%; group 2: 91% and 65%; and group 3: 58% and 34%, respectively. CONCLUSIONS: Serial monitoring of plasma PST is useful in predicting long-term survival following surgical cytoreduction and can be helpful to identify patients who have a poor prognosis.


Asunto(s)
Biomarcadores de Tumor/sangre , Cromogranina A/sangre , Procedimientos Quirúrgicos de Citorreducción/métodos , Intestino Delgado/cirugía , Tumores Neuroendocrinos/cirugía , Adulto , Anciano , Femenino , Humanos , Intestino Delgado/patología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico , Pronóstico , Resultado del Tratamiento , Adulto Joven
15.
Int J Radiat Oncol Biol Phys ; 103(2): 335-343, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30312717

RESUMEN

PURPOSE: Only retrospective data are available for low-dose-rate (LDR) salvage prostate brachytherapy for local recurrence after external beam radiation therapy (EBRT). The primary objective of this prospective phase 2 trial (NCT00450411) was to evaluate late gastrointestinal and genitourinary adverse events (AEs) after salvage LDR brachytherapy. METHODS AND MATERIALS: Eligible patients had low- or intermediate-risk prostate cancer before EBRT and biopsy-proven recurrence >30 months after EBRT, with prostate-specific antigen levels <10 ng/mL and no regional/distant disease. The primary endpoint was grade 3 or higher late treatment-related gastrointestinal or genitourinary AEs occurring 9 to 24 months after brachytherapy. These AEs were projected to be ≤10%, with ≥20% considered unacceptable. All events were graded with National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Multivariate analyses investigated associations of pretreatment or treatment variables with AEs. RESULTS: One hundred patients from 20 centers were registered from May 2007 to January 2014. The 92 analyzable patients had a median follow-up of 54 months (range, 4-97) and a median age of 70 years (interquartile range [IQR], 65-74). The initial Gleason score was 7 in 48% of patients. The median dose of EBRT was 74 Gy (IQR, 70-76) at a median interval of 85 months previously (IQR, 60-119). Only 16% had androgen deprivation at study entry. Twelve patients (14%) had late grade 3 gastrointestinal/genitourinary AEs, with no treatment-related grade 4 or 5 AEs. No pretreatment variable predicted late AEs, including prior EBRT dose and elapsed interval. Higher V100 (percentage of prostate enclosed by prescription isodose) predicted both occurrence of late AEs (odds ratio, 1.24; 95% confidence interval, 1.02-1.52; P = .03) and earlier time to first occurrence (hazard ratio, 1.18; 95% CI, 1.03-1.34; P = .02). CONCLUSIONS: This prospective multicenter trial reports outcomes of salvage LDR brachytherapy for post-EBRT recurrence. The rate of late grade 3 AEs did not exceed the unacceptable threshold. The only factor predictive of late AEs was implant dosimetry reflected by V100. Efficacy outcomes will be reported at a minimum of 5-year follow-up.


Asunto(s)
Braquiterapia/efectos adversos , Braquiterapia/métodos , Tracto Gastrointestinal/efectos de la radiación , Neoplasias de la Próstata/radioterapia , Terapia Recuperativa/efectos adversos , Terapia Recuperativa/métodos , Anciano , Biopsia , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Clasificación del Tumor , Recurrencia Local de Neoplasia/radioterapia , Estudios Prospectivos , Próstata , Antígeno Prostático Específico , Dosificación Radioterapéutica , Radioterapia Guiada por Imagen/efectos adversos , Radioterapia Guiada por Imagen/métodos , Resultado del Tratamiento , Ultrasonografía
16.
Gland Surg ; 8(6): 609-617, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32042667

RESUMEN

BACKGROUND: In breast cancer treatment, marking the tumor bed is an important aspect of the surgical component of therapy. Clear delineation of the tumor bed allows radiation oncologists a defined target for planning and delivering postoperative radiation therapy (XRT). Tumor bed marking also allows radiographic follow-up of the tumor bed on subsequent breast imaging. The aim of this assessment is to evaluate the ease and feasibility of utilizing a tumor bed filament marker (VeraFormÒ, Videra Surgical inc., USA) as a marker in post-operative benign surgical sites and malignant breast surgical tumor beds in breast cancer surgery. METHODS: The filament marker is a novel radiopaque surgical filament that in lieu of clips and other markers is implanted in the surgical tumor bed during breast surgery. Following development of the filament marker, the researchers used breast phantoms and radiographic images to develop a series of geometric patterns of placement options that optimize comprehensive multi-plane radiographic interpretation of the exact tumor bed or surgical margin. Three breast surgeons at 3 separate institutions then used this filament as a continuous multi-plane marker in 20 patients during breast conservation surgery. In these patients, the filament marker was thus used to mark the tumor bed (breast cancer surgery) or surgical site (benign breast disease) instead of the more traditional devices such as clips or other metallic open framework devices. We then assessed 2 important factors related to this device; (I) the ease, feasibility, and accuracy of in vivo placement with oncoplastic and non-oncoplastic breast conservation surgery techniques; (II) the radiographic footprint this device left on standard imaging protocols of post-operative mammogram (MMG), computed tomography (CT) scan, breast magnetic resonance imaging (MRI) examinations, and ultrasounds (USs) for both routine follow-up imaging and for standard radiation planning. RESULTS: There were no adverse events reported with the use of this device. The cases were then reviewed by a multidisciplinary team that included the original surgeon, a breast radiologist, and radiation oncologist. Their unanimous evaluation was that the filament marker clearly delineated all sides and planes of the tumor bed (cancer surgery) or surgical site (benign disease). Regardless of surgical technique utilized, this information provided precise 3D guidance for radiation planning and delivery as well as radiographic follow-up. The surgeons involved reported that delineating the bed with the filament marker was a quick and easy procedure and did not interfere with performing the planned surgical technique. Radiologists, surgeons, and radiation oncologists found that the filament marker was not only radiographically opaque on CT and MMG, but also caused no significant artifact on CT, MRI, US, or MMG. CONCLUSIONS: The continuous multi-plane filament marker is a new device that fulfills the heretofore unmet need for safe and improved tumor bed and tissue site marking. It is an easy to place, non-palpable continuous multi-plane radiographic opaque tissue marker that seems to better delineate the tumor bed, regardless of type of breast surgery performed, while providing a more accurate 3D image for radiation planning and radiographic follow-up on MMG MRI, CT and US.

17.
Int J Radiat Oncol Biol Phys ; 102(2): 287-295, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29913254

RESUMEN

PURPOSE: There is considerable interest in very short (ultrahypofractionated) radiation therapy regimens to treat prostate cancer based on potential radiobiological advantages, patient convenience, and resource allocation benefits. Our objective is to demonstrate that detectable changes in health-related quality of life measured by the bowel and urinary domains of the Expanded Prostate Cancer Index Composite (EPIC-50) were not substantially worse than baseline scores. METHODS AND MATERIALS: NRG Oncology's RTOG 0938 is a nonblinded randomized phase 2 study of National Comprehensive Cancer Network low-risk prostate cancer in which each arm is compared with a historical control. Patients were randomized to 5 fractions (7.25 Gy in 2 weeks) or 12 fractions (4.3 Gy in 2.5 weeks). The co-primary endpoints were the proportion of patients with a change in EPIC-50 bowel score at 1 year (baseline to 1 year) >5 points and in EPIC-50 urinary score >2 points tested with a 1-sample binomial test. RESULTS: The study enrolled 127 patients to 5 fractions (121 analyzed) and 128 patients to 12 fractions (125 analyzed). Median follow-up for all patients at the time of analysis was 3.8 years. The 1-year frequency for >5 point change in bowel score were 29.8% (P < .001) and 28.4% (P < .001) for 5 and 12 fractions, respectively. The 1-year frequencies for >2 point change in urinary score were 45.7% (P < .001) and 42.2% (P < .001) for 5 and 12 fractions, respectively. For 5 fractions, 32.9% of patients had a drop in 1-year EPIC-50 sexual score of ≥11 points (P = .34); for 12 fractions, 30.9% of patients had a drop in 1-year EPIC-50 sexual score of ≥ 11 points (P = .20). Disease-free survival at 2 years is 99.2% (95% confidence interval: 97.5-100) in the 5-fraction arm and 97.5% (95% confidence interval: 94.6-100) in the 12-fraction arm. There was no late grade 4 or 5 treatment-related urinary or bowel toxicity. CONCLUSIONS: This study confirms that, based on changes in bowel and urinary domains and toxicity (acute and late), the 5- and 12-fraction regimens are well tolerated. These ultrahypofractionated approaches need to be compared with current standard radiation therapy regimens.


Asunto(s)
Órganos en Riesgo/efectos de la radiación , Medición de Resultados Informados por el Paciente , Neoplasias de la Próstata/radioterapia , Calidad de Vida , Hipofraccionamiento de la Dosis de Radiación , Anciano , Supervivencia sin Enfermedad , Cabeza Femoral/efectos de la radiación , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pene/efectos de la radiación , Neoplasias de la Próstata/mortalidad , Radioterapia/métodos , Radioterapia/estadística & datos numéricos , Recto/efectos de la radiación , Uretra/efectos de la radiación , Vejiga Urinaria/efectos de la radiación
18.
Pancreas ; 47(7): 843-848, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29939909

RESUMEN

OBJECTIVES: Elevated neurokinin A (NKA) levels are associated with poor prognosis in patients with small bowel neuroendocrine tumors. We hypothesized that patients with NKA levels that remain elevated despite treatment with surgical cytoreduction have a poor prognosis. METHODS: Patients diagnosed with small bowel neuroendocrine tumors who underwent surgical cytoreduction at our institution were identified. Demographics, histopathologic characteristics, and biochemical data were collected. Patients were grouped by the trend of their NKA levels (group 1, continuously normal; group 2, transiently elevated but normalized after therapy; group 3, remained elevated despite therapy). Survival rates were calculated from the date of the patient's first NKA level. RESULTS: Serial NKA values after surgical cytoreduction were monitored in 267 patients. Kaplan-Meier 2-year, 5-year, and 10-year survival rates were as follows: group 1 (n = 157), 97%, 89%, and 62%; group 2 (n = 78), 99%, 90%, and 78%; and group 3 (n = 32), 88%, 69%, and 0%. Survival rates were statistically significant between groups 1 and 3 and between groups 2 and 3 (P < 0.01). CONCLUSIONS: Serial monitoring of plasma NKA levels is useful in identifying patients who have a poor prognosis. Elevated NKA levels can indicate the need for immediate therapeutic intervention.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Intestinales/cirugía , Intestino Delgado/cirugía , Tumores Neuroendocrinos/cirugía , Neuroquinina A/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Intestinales/sangre , Neoplasias Intestinales/diagnóstico , Intestino Delgado/patología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/sangre , Tumores Neuroendocrinos/diagnóstico , Valor Predictivo de las Pruebas , Pronóstico , Adulto Joven
19.
Pract Radiat Oncol ; 8(1): e7-e15, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28951089

RESUMEN

BACKGROUND: We previously reported the results of a phase 3 trial evaluating a prostate/rectal hydrogel spacer during prostate intensity modulated radiation therapy, which resulted in decreased rectal dose and toxicity and less decline in bowel quality of life (QOL). A secondary analysis was performed to correlate penile bulb dose and sexual QOL. METHODS AND MATERIALS: Sexual QOL was measured with the Expanded Prostate Cancer Index Composite (EPIC) by mean scores, the proportion of patients with a minimal clinically important difference (MID), and analyses of the different items composing the sexual domain. RESULTS: A total of 222 men enrolled with median follow-up of 37 months. Hydrogel reduced penile bulb mean dose, maximum dose, and percentage of penile bulb receiving 10 to 30 Gy (all P < .05) with mean dose indirectly correlated with erections sufficient for intercourse at 15 months (P = .03). Baseline EPIC was low (53 [standard deviation ± 24]) with no difference between arms (P > .1). A total of 41% (88/222) of men had adequate baseline sexual QOL (EPIC >60 (mean, 77 [± 8.3]). This subgroup at 3 years had better sexual function (P = .03) with a spacer with a smaller difference in sexual bother (P = .1), which resulted in a higher EPIC summary on the spacer arm (58 [±24.1] vs control 45 [± 24.4]) meeting threshold for MID without statistical significance (P = .07). There were statistically nonsignificant differences favoring spacer for the proportion of men with MID and 2× MID declines in sexual QOL with 53% vs 75% having an 11-point decline (P = .064) and 41% vs 60% with a 22-point decline (P = .11). At 3 years, more men potent at baseline and treated with spacer had "erections sufficient for intercourse" (control 37.5% vs spacer 66.7%, P = .046) as well as statistically higher scores on 7 of 13 items in the sexual domain (all P < .05). CONCLUSIONS: The use of a hydrogel spacer decreased dose to the penile bulb, which was associated with improved erectile function compared with the control group based on patient-reported sexual QOL.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Calidad de Vida/psicología , Radioterapia de Intensidad Modulada/psicología , Conducta Sexual/psicología , Humanos , Masculino , Radioterapia de Intensidad Modulada/métodos
20.
Ochsner J ; 17(4): 335-340, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29230118

RESUMEN

BACKGROUND: Typical and atypical carcinoids represent approximately 2% of all lung tumors. Survival of patients with typical bronchial carcinoids, unlike the survival of patients with most lung tumors, is generally long but dependent on stage. We report the findings of the Ochsner Medical Center/Louisiana State University (LSU) Health Sciences Center neuroendocrine tumor (NET) program. METHODS: A database with all patients seen at the Ochsner Medical Center/LSU NET program was queried for patients with bronchopulmonary NET. We included patients who had confirmed pathologic bronchopulmonary carcinoid and who had at least 1 clinic visit. Patients with large or small cell NETs or diffuse idiopathic pulmonary neuroendocrine cell hyperplasia were excluded. RESULTS: A total of 169 patients seen from January 1996 to March 2015 met the inclusion criteria. The mean age at diagnosis was 53 years. Of the tumors, 51% percent (86/169) were well-differentiated, 12% (21/169) were moderately differentiated, and 85% and 53% were positive on positron emission tomography and octreotide scanning, respectively. The 5- and 10-year survival rates were 88% and 81% for well-differentiated tumors and 80% and 42% for moderately differentiated tumors, respectively. The 10-year survival rates stratified by Ki-67 index ranges 0-2%, >2%-10%, and >10% were 90%, 72%, and 44%, respectively (P<0.05). CONCLUSION: Overall, patients with bronchial carcinoids have long 5- and 10-year survival rates. We found significant survival differences between nodal status, differentiation status, and carcinoid phenotype. Interestingly, the difference in survival stratified by Ki-67 indices was statistically significant despite its absence in the World Health Organization grading system. As with gastroenteropancreatic NETs, Ki-67 index could become a valuable prognostic indicator for bronchial carcinoids.

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