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PURPOSE: Determine rates of intra-parotid and neck nodal metastasis, identify risk factors for recurrence, and report outcomes in patients with primary high-grade parotid malignancy who undergo total parotidectomy and neck dissection. MATERIALS & METHODS: Retrospective review of patients undergoing total parotidectomy and neck dissection for high-grade parotid malignancy between 2005 and 2015. The presence and number of parotid lymph nodes, superficial and deep, as well as cervical lymph nodes involved with metastatic disease were assessed. Risk factors associated with metastatic spread to the parotid deep lobe were identified and recurrence rates reported. RESULTS: 75 patients with median follow-up time of 47 months. 35 patients (46.7%) had parotid lymph node metastasis. Seven patients (9.3%) had deep lobe nodal metastasis without metastasis to the superficial lobe nodes. Nine patients (12%) had positive intra-parotid nodes without positive cervical nodes. Cervical nodal disease was identified in 49.3% patients (37/75). Local, parotid-bed recurrence rate was 5.3% (4/75). Regional lymph node recurrence rate was also 5.3% (4/75). Rate of distant metastasis was 30.6% (23/75). The overall disease free survival rate for all patients at 2 and 5 years were 71% and 60% respectively. CONCLUSION: Parotid lymph node metastasis occurred at a similar rate to cervical lymph node metastasis (46.7% and 49.3%, respectively). Deep lobe parotid nodal metastasis occurred in nearly a quarter of patients and can occur without superficial parotid nodal metastasis. Rate of recurrence in the parotid bed, which may represent local or regional recurrence, was similar to regional cervical lymph node recurrence. Total parotidectomy and neck dissection should be considered high-grade parotid malignancy regardless of clinical nodal status.
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Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Disección del Cuello , Glándula Parótida/cirugía , Neoplasias de la Parótida/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Cuello , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Glándula Parótida/patología , Neoplasias de la Parótida/mortalidad , Neoplasias de la Parótida/patología , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
This study investigated how differences in drug distribution and free fraction at different tumor and tissue sites influence the efficacy of the multikinase inhibitor ponatinib in a patient-derived xenograft model of glioblastoma (GBM). Efficacy studies in GBM6 flank (heterotopic) and intracranial (orthotopic) models showed that ponatinib is effective in the flank but not in the intracranial model, despite a relatively high brain-to-plasma ratio. In vitro binding studies indicated that flank tumor had a higher free (unbound) drug fraction than normal brain. The total and free drug concentrations, along with the tissue-to-plasma ratio (Kp) and its unbound derivative (Kp,uu), were consistently higher in the flank tumor than the normal brain at 1 and 6 hours after a single dose in GBM6 flank xenografts. In the orthotopic xenografts, the intracranial tumor core displayed higher Kp and Kp,uu values compared with the brain-around-tumor (BAT). The free fractions and the total drug concentrations, hence free drug concentrations, were consistently higher in the core than in the BAT at 1 and 6 hours postdose. The delivery disadvantages in the brain and BAT were further evidenced by the low total drug concentrations in these areas that did not consistently exceed the in vitro cytotoxic concentration (IC50). Taken together, the regional differences in free drug exposure across the intracranial tumor may be responsible for compromising efficacy of ponatinib in orthotopic GBM6.
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Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Glioblastoma/metabolismo , Imidazoles/metabolismo , Inhibidores de Proteínas Quinasas/metabolismo , Piridazinas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Animales , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Encéfalo/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Femenino , Glioblastoma/tratamiento farmacológico , Células HEK293 , Humanos , Imidazoles/farmacología , Imidazoles/uso terapéutico , Masculino , Ratones , Ratones Desnudos , Unión Proteica/fisiología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridazinas/farmacología , Piridazinas/uso terapéutico , Distribución Aleatoria , Resultado del TratamientoRESUMEN
Small molecule inhibitors targeting the mitogen-activated protein kinase pathway (Braf/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase) have had success in extending survival for patients with metastatic melanoma. Unfortunately, resistance may occur via cross-activation of alternate signaling pathways. One approach to overcome resistance is to simultaneously target the phosphoinositide 3-kinase/mammalian target of rapamycin signaling pathway. Recent reports have shown that GSK2126458 [2,4-difluoro-N-(2-methoxy-5-(4-(pyridazin-4-yl)quinolin-6-yl)pyridin-3-yl) benzenesulfonamide], a dual phosphoinositide 3-kinase/mammalian target of rapamycin inhibitor, can overcome acquired resistance to Braf and mitogen-activated protein kinase kinase inhibitors in vitro. These resistance mechanisms may be especially important in melanoma brain metastases because of limited drug delivery across the blood-brain barrier. The purpose of this study was to investigate factors that influence the brain distribution of GSK2126458 and to examine the efficacy of GSK2126458 in a novel patient-derived melanoma xenograft (PDX) model. Both in vitro and in vivo studies indicate that GSK2126458 is a substrate for P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp), two dominant active efflux transporters in the blood-brain barrier. The steady-state brain distribution of GSK2126458 was 8-fold higher in the P-gp/Bcrp knockout mice compared with the wild type. We also observed that when simultaneously infused to steady state, GSK212658, dabrafenib, and trametinib, a rational combination to overcome mitogen-activated protein kinase inhibitor resistance, all had limited brain distribution. Coadministration of elacridar, a P-gp/Bcrp inhibitor, increased the brain distribution of GSK2126458 by approximately 7-fold in wild-type mice. In the PDX model, GSK2126458 showed efficacy in flank tumors but was ineffective in intracranial melanoma. These results show that P-gp and Bcrp are involved in limiting the brain distribution of GSK2126458 and provide a rationale for the lack of efficacy of GSK2126458 in the orthotopic PDX model.
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Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Melanoma/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Quinolinas/metabolismo , Sulfonamidas/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Protocolos de Quimioterapia Combinada Antineoplásica , Encéfalo/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Perros , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/fisiología , Femenino , Células de Riñón Canino Madin Darby , Masculino , Melanoma/tratamiento farmacológico , Ratones , Ratones Noqueados , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/metabolismo , Piridazinas , Quinolinas/farmacología , Quinolinas/uso terapéutico , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Hydropower UV disinfection has not been explored as a possible alternative for off-grid disinfection. Hydropowered UV LED technology was developed using off-the-shelf UV-C LEDs and pico - and femto-scale hydro turbine generators and evaluated across point-of-use relevant flow rates. Commercially available UV LED flow through reactors were subjected to microorganism challenge testing with 3 power schemes: wall-plug, hydropower, and hydropower-charged battery. UV LEDs powered by hydropower-charged battery demonstrated similar disinfection as wall-plug powered UV LEDs, achieving 0.5-1.8 MS2 log10 reduction at flow rates 0.5-2.3 L min-1, corresponding to reduction equivalent doses (RED) up to 16 or 30 mJ/cm2 for 254 and 285 nm, respectively. With hydropowered UV LEDs alone, MS2 log10 reduction decreased to <0.3 log10 reduction due to an underperforming and grossly inefficient turbine, with RED of 8 or 18 mJ/cm2 for 254 and 285 nm, respectively. Assessment of existing markets of UV disinfection systems and pico-hydro turbines demonstrated that hydropowered UV systems are already theoretically feasible for scales at point-of-entry (POE) and above. Economic feasibility will improve if turbines and/or UV system efficiencies improve. Prototype hydropower UV LED systems ranged from $145 to 220 depending on the UV LED reactor, and the battery system added $81. This study demonstrates the practicality of sustainable, renewable energy POU UV disinfection technology that can benefit decentralised, off-grid, rural and remote communities. The system may also scale up to provide renewable energy disinfection at larger scales, such as buildings and water distribution systems, for protecting human health in highly populated areas.
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PURPOSE: Quantitative bibliometrics are increasingly used to evaluate faculty research productivity. This study benchmarks publication rates for radiation oncologists from highly ranked National Cancer Institute-designated cancer centers and reveals how productivity changes over the arc of a career and of the field over time. METHODS AND MATERIALS: Peer-reviewed articles from 1970 to 2022 were obtained using Scopus for the 348 radiation oncologists listed as faculty for the top 10 cancer hospitals ranked by US News and World Report in 2022. Bibliometrics were analyzed for authorships (AË), authorships where the individual was first or last author (FËL), the monograph equivalent of authorships (MËE), h-index, and ha-index (an analog to h-index using MËE in place of publications). Career start was defined as the year of first publication. Bibliometric inflation was explored by analyzing authorship and bibliometric changes between 1990 and 2022. RESULTS: Publication rates peak, with as much as a 500% increase, 20 to 25 years from the start of a career before declining until retirement. At career ages of 1, 10, 20, and 30 years, the median bibliometrics were AË = (1.5, 4.1, 6.5, 7.0) year-1, FËL = (0.5, 0.9, 1.2, 0.6) year-1, MËE= (0.2, 0.5, 0.7, 0.8) year-1, h-index = (1, 12, 22, 47), and ha-index = (0.4, 4.4, 6.9, 18.4). With regards to authorship patterns across eras, the median number of authors listed per paper increased by 240% between 1990 and 2022. Meanwhile, research productivity per individual as measured by FËL and MËE was unchanged. CONCLUSIONS: The research publication rates of the median radiation oncologist change substantially over the course of their career. Productivity improves steadily for more than 2 decades before peaking and declining. The culture of authorship has also changed between 1990 and 2022. The number of authors listed per paper has trended upwards, which has an inflationary effect on the number of authorships and h-index. Meanwhile, the rate of manuscripts published per faculty has not changed.
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Neoplasias , Oncólogos de Radiación , Humanos , Publicaciones , Bibliometría , Docentes , AutoriaRESUMEN
Purpose: To assess any correlation between swallowing dysfunction and radiation dose to 5 subregions of the larynx. Methods and Materials: A cohort of 136 patients with head and neck cancer, treated with either photon or proton radiation therapy, was assessed using an endpoint of patient-reported swallowing scores, evaluated with the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-H&N35 survey, within 1 month after treatment. Five subregions of the larynx were contoured, and dosimetric metrics were extracted for each subregion as well as the total larynx. Univariate and multivariate logistic regression statistical analyses were used to determine statistical correlation with the dose metrics and clinical variables. Univariate regression models were statistically compared using a non-nested model test. Results: Under univariate analysis, unilateral versus bilateral nodal irradiation (P = .004), concurrent chemotherapy (P = .007), and surgery (P = .015) were statistically significant predictors of poor swallowing score. Unilateral versus bilateral irradiation was statistically significant under multivariate analysis (P = .039). The epiglottis was the most predictive subregion of swallowing score, with a majority (21 of 25) of dosimetric variables being identified as statistically significant. The maximum dose to the epiglottis was the most significant dosimetric variable tested for poor swallowing score in both univariate (P = .003) and multivariate (P = .051) analyses. Comparison of univariate models indicated a general preference for epiglottic variables with the mean dose to the epiglottis being preferred at a statistically significant level in many cases. Conclusions: These results show the relatively increased sensitivity of the epiglottis compared with the rest of the larynx when considering patient-reported decrements in quality-of-life swallowing score and support both the inclusion of the epiglottis in standard larynx contours and the assessment of the epiglottis dose during plan evaluation. Our data suggest that keeping the mean and max doses to the epiglottis <20 to 37 Gy and <53 to 60 Gy, respectively, will reduce swallowing difficulties.
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Objectives: To investigate the relationship between nutritional supplementation and radiation dose to the pharyngeal constrictor muscles and larynx for head and neck (HN) cancer patients undergoing radiotherapy. Methods: We retrospectively analyzed radiotherapy (RT) dose for 231 HN cancer patients, focusing on the pharyngeal constrictors and larynx. We defined nutritional supplementation as feeding tube utilization or >10% weight loss from baseline within 90 days after radiotherapy completion. Using deformable image registration (DIR), we mapped each patient's anatomical structures to a reference coordinate system, and corresponding deformations were applied to dose matrices. Voxel doses were utilized as features for ridge logistic regression models, optimized through 5-fold cross-validation. Model performance was assessed with area under the curve of a receiver operating curve (AUC) and F1 score. We built and compared models using 1) pharyngeal constrictor voxels, 2) larynx voxels, 3) clinical factors and mean regional dose metrics, and 4) clinical factors and dose-volume histogram metrics. Test set AUCs were compared among the models, and feature importance was evaluated. Results: DIR of the pharyngeal constrictors and larynx yielded mean Dice coefficients of 0.80 and 0.84, respectively. Pharyngeal constrictors voxels and larynx voxel models had AUC of 0.88 and 0.82, respectively. Voxel-based dose modeling identified the superior to middle regions of the pharyngeal constrictors and the superior region of larynx as most predictive of feeding tube use/weight loss. Univariate analysis found treatment setting, treatment laterality, chemotherapy, baseline dysphagia, weight, and socioeconomic status predictive of outcome. An aggregated model using mean doses of pharyngeal constrictors and larynx subregions had an AUC of 0.87 and the model using conventional DVH metrics had an AUC of 0.85 with p-value of 0.04. Feature importance calculations from the regional dose model indicated that mean doses to the superior-middle pharyngeal constrictor muscles followed by mean dose to the superior larynx were most predictive of nutritional supplementation. Conclusions: Machine learning modeling of voxel-level doses enables identification of subregions within organs that correlate with toxicity. For HN radiotherapy, doses to the superior-middle pharyngeal constrictors are most predictive of feeding tube use/weight loss followed by the doses to superior portion of the larynx.
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Objective. An algorithm was developed for automated positioning of lattice points within volumetric modulated arc lattice radiation therapy (VMAT LRT) planning. These points are strategically placed within the gross tumor volume (GTV) to receive high doses, adhering to specific separation rules from adjacent organs at risk (OARs). The study goals included enhancing planning safety, consistency, and efficiency while emulating human performance.Approach. A Monte Carlo-based algorithm was designed to optimize the number and arrangement of lattice points within the GTV while considering placement constraints and objectives. These constraints encompassed minimum spacing between points, distance from OARs, and longitudinal separation along thez-axis. Additionally, the algorithm included an objective to permit, at the user's discretion, solutions with more centrally placed lattice points within the GTV. To validate its effectiveness, the automated approach was compared with manually planned treatments for 24 previous patients. Prior to clinical implementation, a failure mode and effects analysis (FMEA) was conducted to identify potential shortcomings.Main results.The automated program successfully met all placement constraints with an average execution time (over 24 plans) of 0.29 ±0.07 min per lattice point. The average lattice point density (# points per 100 c.c. of GTV) was similar for automated (0.725) compared to manual placement (0.704). The dosimetric differences between the automated and manual plans were minimal, with statistically significant differences in certain metrics like minimum dose (1.9% versus 1.4%), D5% (52.8% versus 49.4%), D95% (7.1% versus 6.2%), and Body-GTV V30% (20.7 c.c. versus 19.7 c.c.).Significance.This study underscores the feasibility of employing a straightforward Monte Carlo-based algorithm to automate the creation of spherical target structures for VMAT LRT planning. The automated method yields similar dose metrics, enhances inter-planner consistency for larger targets, and requires fewer resources and less time compared to manual placement. This approach holds promise for standardizing treatment planning in prospective patient trials and facilitating its adoption across centers seeking to implement VMAT LRT techniques.
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Algoritmos , Benchmarking , Humanos , Estudios Prospectivos , Método de Montecarlo , Órganos en RiesgoRESUMEN
BACKGROUND: Head and neck cancers (HNC) present diagnostic challenges due to multifocal disease manifestations, posing difficulties in distinguishing between metastatic disease and second primary malignancies (SPM). This complexity underscores the need for advanced diagnostic approaches. Emerging technologies, such as next-generation sequencing (NGS) and molecular classifier assays, show promise in providing precise insights into the diverse etiologies of HNC. METHOD: In this article, we employed NGS and molecular classifier assays to delve into three distinct clinical cases. The objective was to showcase the instrumental role of these technologies in facilitating accurate diagnoses and differentiating between metastatic disease and SPM in HNC cases. RESULTS: The results of this series highlight the effectiveness of NGS and molecular classifier assays in enhancing diagnostic accuracy for HNC and contributing to the precise differentiation of disease etiologies. The utilization of these advanced technologies proved instrumental in avoiding unnecessary interventions and paved the way for more targeted and effective treatment strategies. CONCLUSION: Our findings underscore the necessity of incorporating advanced molecular testing technologies into the diagnostic and therapeutic approaches for HNC, thereby championing a more nuanced and effective approach to managing these complex cases.
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PURPOSE: Patients undergoing radiation therapy may terminate treatment for any number of reasons. The incidence of treatment termination (TT) during radiation therapy has not been studied. Herein, we present a cohort of TT at a large multicenter radiation oncology department over 10 years. METHODS AND MATERIALS: TTs between January 2013 and January 2023 were prospectively analyzed as part of an ongoing departmental quality and safety program. TT was defined as any premature discontinuation of therapy after initiating radiation planning. The rate of TT was calculated as a percentage of all patients starting radiation planning. All cases were presented at monthly morbidity and mortality conferences with a root cause reviewed. RESULTS: A total of 1448 TTs were identified out of 31,199 planned courses of care (4.6%). Six hundred eighty-six (47.4%) involved patients treated with curative intent, whereas 753 (52.0%) were treated with palliative intent, and 9 (0.6%) were treated for benign disease. The rate of TT decreased from 8.49% in 2013 to 3.02% in 2022, with rates decreasing yearly. The most common disease sites for TT were central nervous system (21.7%), head and neck (19.3%), thorax (17.5%), and bone (14.2%). The most common causes of TT were hospice and/or patient expiration (35.9%), patient choice unrelated to toxicity (35.2%), and clinician choice unrelated to toxicity (11.5%). CONCLUSIONS: This 10-year prospective review of TTs identified a year-over-year decrease in TTs as a percentage of planned patients. This decrease may be associated with the addition of root cause reviews for TTs and discussions monthly at morbidity and mortality rounds, coupled with departmental upstream quality initiatives implemented over time. Understanding the reasons behind TTs may help decrease preventable TTs. Although some TTs may be unavoidable, open discourse and quality improvement changes effectively reduce TT incidents over time.
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Treatment of squamous cell carcinoma of the tonsil involves primary radiation therapy (RT) or surgical resection. Historically, if RT was the primary or adjuvant treatment modality, most of the bilateral retropharyngeal lymph nodes (RPLNs) were treated electively with a therapeutic dose for subclinical disease, regardless of whether radiographically pathologic lymph nodes were seen on initial diagnostic imaging. De-escalation strategies include the incorporation of transoral surgery with the goal to either eliminate or reduce the dose of adjuvant RT or chemotherapy. Transoral surgery does not include elective removal of the RPLNs, and no guideline or outcome paper recommends adjuvant RT specifically to electively treat RPLNs. In this Topic Discussion, we discuss pertinent literature and suggest management decisions. The management decisions discussed in this Topic Discussion pertain to only tonsillar primaries and not those of the soft palate or base of the tongue.
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BACKGROUND: Approximately 75% of all head and neck cancer patients are treated with radiotherapy (RT). RT to the oral cavity results in acute and late adverse events which can be severe and detrimental to a patient's quality of life and function. The purpose of this study was to explore associations between RT dose to a defined oral cavity organ-at-risk (OAR) avoidance structure, provider- and patient-reported outcomes (PROs), opioid use, and hospitalization. METHODS: This was a retrospective analysis of prospectively obtained outcomes using multivariable modeling. The study included 196 patients treated with RT involving the oral cavity for a head and neck tumor. A defined oral cavity OAR avoidance structure was used in all patients for RT treatment planning. Validated PROs were collected prospectively. Opioid use and hospitalization were abstracted electronically from medical records. RESULTS: Multivariable modeling revealed the mean dose to the oral cavity OAR was significantly associated with opioid use (p = 0.0082) and hospitalization (p = 0.0356) during and within 30 days of completing RT. CONCLUSIONS: The findings of this study may be valuable in RT treatment planning for patients with tumors of the head and neck region to reduce the need for opioid use and hospitalization during treatment.
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OBJECTIVES: Social determinants of health (SDOH) can influence access to cancer care, clinical trials, and oncologic outcomes. We investigated the association between SDOH, distance from treatment center, and treatment type with outcomes in human papillomavirus associated oropharyngeal squamous cell carcinoma [HPV(+)OPSCC] patients treated at a tertiary care center. STUDY DESIGN: Retrospective review. METHODS: HPV(+)OPSCC patients treated surgically from 2006 to 2021 were selected from our departmental Oropharyngeal Cancer RedCap database. Demographic data, treatment, and oncologic outcomes were extracted. Distance was calculated in miles between the centroid of each patient zip code and our hospital zip code (zipdistance). RESULTS: 874 patients (89 % male; mean age: 58 years) were identified. Most patients (96 %) reported Non-Hispanic White as their primary race. 204 patients (23 %) had a high-school degree or less, 217 patients (25 %) reported some college education or a 2-year degree, 153 patients (18 %) completed a four-year college degree, and 155 patients (18 %) had post-graduate degrees. Relative to those with a high-school degree, patients with higher levels of education were more likely to live further away from our institution (p < 0.0001). Patients who received adjuvant radiation therapy elsewhere lived, on average, 104 miles further away than patients receiving radiation at our institution (Estimate 104.3, 95 % CI 14.2-194.4, p-value = 0.02). In univariable Cox PH models, oncologic outcomes did not significantly differ by zipdistance. CONCLUSIONS: Education level-and access to resources-varied proportionally to a patient's distance from our center. Patients travelling further distances for surgical management of OPSCC were more likely to pursue adjuvant radiation therapy at an outside institution. Distance traveled was not associated with oncologic outcomes. Breaking down barriers to currently excluded populations may improve access to clinical trials and improve oncologic outcomes for diverse patient populations.
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Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Humanos , Masculino , Persona de Mediana Edad , Femenino , Virus del Papiloma Humano , Carcinoma de Células Escamosas/patología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/patología , Determinantes Sociales de la Salud , Neoplasias Orofaríngeas/patología , Estudios Retrospectivos , Neoplasias de Cabeza y Cuello/complicacionesRESUMEN
Ultraviolet disinfection is a promising solution for decentralized drinking water systems such as communal water taps. A potential health risk is enzymatic photorepair of pathogens after UV disinfection, which can result in regrowth of pathogens. Even though photorepair is a known issue, no formal risk assessments have been conducted for photorepair after UV disinfection in drinking water. The main objective was to construct a quantitative microbial risk assessment (QMRA) of photorepair after UV disinfection of drinking water in a decentralized system. UV disinfection and photorepair kinetics for E. coli were modelled using reproducible fluence-based determinations. Impacts of water collection patterns, and wavelength-dependent water container material transmittance, sunlight intensity, and photorepair enzyme absorbance were quantified. After UV disinfection by 16 or 40 mJ/cm2 of < 5-log microorganisms per L, risk of infection did not exceed 1-in-10,000 under conditions permitting E. coli photorepair. Risk from photorepair was less than 1-in-10,000 for photorepair light exposure < 0.75 h throughout the day for UV fluence 16 mJ/cm2 or greater. UV disinfection followed by solar disinfection surpassing photoreactivation during storage reduced risk below 1-in-10,000 for photorepair light exposure > 2.5 h between modelled times of 9 AM - 3 PM. The model can be expanded to other pathogens as UV fluence and photorepair fluence response kinetics become available, and this QMRA can be used to inform the placement of community water access points to reduce risk of photorepair and ensure adequate shelf life of UV disinfected water under safe storage conditions.
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Agua Potable , Purificación del Agua , Rayos Ultravioleta , Escherichia coli , Desinfección , Medición de Riesgo , BacteriasRESUMEN
The purpose of this article is to summarize the literature and practical recommendations from experienced centers for close margins after transoral robotic surgery for human papillomavirus-positive oropharyngeal carcinoma.
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Carcinoma de Células Escamosas , Neoplasias Orofaríngeas , Procedimientos Quirúrgicos Robotizados , Humanos , Virus del Papiloma Humano , Carcinoma de Células Escamosas/patología , Neoplasias Orofaríngeas/cirugía , Neoplasias Orofaríngeas/patología , Estudios RetrospectivosRESUMEN
The purpose of this study was to directly compare the plan quality of Gamma Knife (GK) (Elekta, Stockholm, Sweden)- vs linear accelerator (LINAC)-based delivery techniques for fractionated stereotactic radiotherapy (fSRT) of large brain metastases. Eighteen patients with clinical target volumes (CTVs) larger than 9.5 cc were selected to generate comparative plans for the prescription dose of 9 Gyâ¯×â¯3 fractions, utilizing the Eclipse (Varian, Palo Alto, US) vs Leksell GammaPlan (LGP) (Elekta, Stockholm, Sweden) treatment planning systems (TPS). Each GK plan was first developed using LGP's automatic planning, followed by manual adjustments/refinements. The same MRI and structures, including CTVs and organs at risk, were then DICOM-transferred to the Eclipse TPS. Volumetric Modulated Arc Therapy (VMAT) and Dynamic Conformal Arc (DCA) plans for a Truebeam, with high-definition multi-leaf collimators (MLCs), were developed on these MR images and structures using a single isocenter and 3 non-coplanar arcs. No planning target volume (PTV) margins were added, and no heterogeneity correction was used for either TPS. GK plans were prescribed to the 50% isodose line, and Eclipse VMAT and DCA plans allowed a maximum dose up to 170% and â¼125%, respectively. Gradient index (GI), Paddick Conformity Index (PCI), V20GyRind, and V4GyRind of all 3 techniques were calculated and compared. One-way analysis of variance (ANOVA) was performed to determine the statistical significance of the differences of these planning indices for the 3 planning techniques. A total of eighteen treatment targets were analyzed. Median CTV volume was 14.4 cc (range 9.5 cc - 55.9 cc). Mean ± standard deviation of PCI were 0.85 ± 0.03, 0.90 ± 0.03, and 0.72 ± 0.11 for GK, VMAT and DCA plans, respectively. They were respectively 2.64 ± 0.17, 2.46 ± 0.18, and 2.83 ± 0.48 for GI; 15.33 ± 8.45 cc, 10.47 ± 4.32 cc and 23.51 ± 16 cc for V20GyRind; and 316.28 ± 138.35 cc, 317.81 ± 108.21 cc, and 394.85 ± 142.16 cc for V4GyRind. The differences were statistically significant with p < 0.01 for all indices, except for V4GyRind (p > 0.129). In conclusion, a direct dosimetric comparison using the same MRI scan and contours was performed to evaluate the plan quality of various fSRT delivery techniques for CTV > 9.5 cc. LINAC VMAT plans provided the best dosimetric outcome in regard to PCI, GI, and V20GyRind. GK outcomes were similar to LINAC VMAT plans while LINAC DCA outcomes were significantly worse. Even though GK has a smaller physical penumbra, LINAC VMAT outperformed GK in this study due to enhanced penumbra sharpening and better beam optimization.
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Neoplasias Encefálicas , Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radiocirugia/métodos , Aceleradores de Partículas , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Radioterapia de Intensidad Modulada/métodosRESUMEN
BACKGROUND: For patients with either an incompletely resected meningioma or recurrence after surgery, stereotactic radiosurgery is frequently used. MRI is typically used for stereotactic radiosurgery targeting, but differentiating tumor growth from postoperative change can be challenging. 68 Ga-DOTATATE, a positron emission tomography (PET) radiotracer targeting the somatostatin receptor type 2, has been shown to be a reliable meningioma biomarker. OBJECTIVE: To evaluate the impact of 68 Ga-DOTATATE on treatment planning in patients who had previously undergone meningioma resection. METHODS: We present a consecutive case series of 12 patients with pathology-proven meningioma who received a 68 Ga-DOTATATE PET between April 2019 and April 2021. Treatment planning was performed first using MRI. DOTATATE-PET images were then used to assess accurate tumor identification. RESULTS: Ten patients had WHO Grade 2 meningioma, and 2 patients had Grade 1 tumor. Eight patients had recurrent meningiomas, and 4 patients had newly diagnosed disease. Overall, 68 Ga-DOTATATE PET scans altered previously formulated treatment plans in 5 of 12 patients. In addition, 9 of 12 patients had disease foci not appreciated on MRI. CONCLUSION: In this series, incorporating 68 Ga-DOTATATE PET imaging had clinical utility for most patients in whom it was used. It proved particularly adept in demonstrating intraosseous meningiomas, differentiating recurrence from postoperative changes, and identifying subcentimeter disease foci. It is an imaging modality that our center will continue to use as a means of improving postoperative treatment plans after the surgical resection of meningiomas.
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Neoplasias Meníngeas , Meningioma , Compuestos Organometálicos , Radiocirugia , Humanos , Meningioma/diagnóstico por imagen , Meningioma/radioterapia , Meningioma/cirugía , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/radioterapia , Neoplasias Meníngeas/cirugía , Recurrencia Local de Neoplasia/cirugía , Tomografía de Emisión de Positrones/métodos , Compuestos Organometálicos/uso terapéuticoRESUMEN
Purpose: Patient experience tools are used throughout health care to evaluate physician and departmental performance. In radiation medicine, these tools are important in evaluating patient-specific metrics throughout their care journey. This study compared patient experience outcomes from a central tertiary cancer program with network clinics in a health care network. Methods and Materials: Radiation medicine patient experience surveys (Press Ganey, LLC) were collected from a central facility and 5 network locations from January 2017 through June 2021. Surveys were distributed to patients after treatment completion. The study cohort was divided into the central facility and satellites. Questions were converted to a 0 to 100 scale from the Likert scale (1-5). To compare scores between site types, 2-way analysis of variance tests for the significance of sites adjusted for years of operations and adjustments for multiple comparisons (Dunnett's test) were completed on each question. Results: The number of consecutively returned surveys analyzed was 3777; a response rate of 33.3% was observed. The central site conducted 117,583 linear accelerator, 1425 Gamma Knife, 273 stereotactic radiosurgery, and 830 stereotactic body radiation therapy procedures. All satellites combined conducted 76,788 linear accelerator, 131 Gamma Knife, 95 stereotactic radiosurgery, and 355 stereotactic body radiation therapy procedures. The central facility fared better than the satellites on "Convenience of parking" (95.9 vs 87.9; P = .0001) but worse in other domains of care. Conclusions: All sites yielded exemplary patient experience rates. Community clinics scored higher than the main campus. The higher scores at the network sites require a deeper analysis of factors influencing the central facility, as the survey did not account for varying patient volumes and disparities in care complexity across sites. Attributes to satellites include lower patient volumes and easily navigable layouts. These results counter the impression that increased resources at the main campus create a better patient experience relative to network clinics and suggest that high-volume tertiary facilities will require unique initiatives to improve the patient experience.
RESUMEN
OBJECTIVE: We aim to explore the prognostic value of tumor-infiltrating lymphocytes (TILs) in the primary tumor and metastatic lymph nodes of patients with HPV(+)OPSCC. We hypothesize that TILS density at both sites is associated with disease-free survival in HPV(+)OPSCC. STUDY DESIGN: Matched case-control study among HPV(+)OPSCC patients who underwent intent-to-cure surgery. Cases developed locoregional or distant recurrence. Controls were matched based on age, sex, pathologic T, N, and overall stage, year of surgery, type of adjuvant treatment received, and the Adult Comorbidity Evaluation-27 (ACE-27) score. SETTING: Single tertiary care center, May 2007 to December 2016. METHODS: Tumoral TILs (tTILs) density was defined as % TILs; stromal TILs (sTILs) density was defined as absent/sparse or moderate/dense crowding. Associations between TILs and time to disease progression were assessed using Cox regression models. RESULTS: Forty-four case-control pairs (N = 88) were included: 42 (48%) AJCC pStage I, 39 (44%) pStage II, and 7 (8%) pStage III. tTILs density ≥10% (hazard ratio [HR] 0.41, 95% confidence interval [CI] 0.17-0.99, p = .048) and a moderate/dense sTILs density (HR 0.21, 95% CI 0.06-0.75, p = .016) in the primary tumor were significantly associated with decreased risk of progression. TILs density in the lymph node was associated with decreased risk of progression but did not reach statistical significance. The tTILs and sTILs density correlated strongly between the primary tumor and lymph node. Concordance between the pathologists' was moderate (60%-70%). CONCLUSIONS: In HPV(+)OPSCC, a higher density of tumoral and stromal TILs in the primary tumor and possibly the lymph node may predict a lower risk of disease progression.
Asunto(s)
Carcinoma , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Adulto , Humanos , Virus del Papiloma Humano , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/patología , Linfocitos Infiltrantes de Tumor , Estudios de Casos y Controles , Pronóstico , Progresión de la Enfermedad , Carcinoma/patologíaRESUMEN
OBJECTIVE: Failure to recognize symptoms of non-human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV(-)OPSCC) at presentation can delay diagnosis and treatment. We aim to identify patient factors and provider practice patterns that delay presentation and care in HPV(-)OPSCC. METHODS: Retrospective review at a tertiary care center. Patients with HPV(-)OPSCC receiving treatment from 2006 to 2016. Patients were excluded if their date of symptom onset or diagnosis was unknown after thorough review of the electronic medical record or their tissue was not tested for HPV or p16. Clinical data, workup, and care timelines were abstracted. Univariate and multivariable linear regressions were performed to determine associations between patient and provider factors and delays in care. RESULTS: Of 70 included patients, 52 (74%) were male and mean age was 60.5 (SD = 9.0). Median time to diagnosis was 69 days (IQR = 32-127 days), with a median latency of 30 days (IQR = 12-61 days) from symptom onset to first presentation and 19.5 days (IQR = 4-46 days) from the first presentation to diagnosis. Most patients visited at least 2 providers (n = 52, 74%) before diagnosis. Evaluation by 3 or more providers prior to diagnosis was associated with significant delays in diagnosis of nearly a year (357.7 days, p < 0.001) and being treated or prescribed analgesia prior to diagnosis was significantly associated with delays in diagnosis (p = 0.004) on univariate regression analysis. CONCLUSIONS: Delays in care related to evaluations by multiple providers and misdiagnosis prolonged time to diagnosis in HPV(-)OPSCC. Improved patient and provider education is necessary to expedite the diagnosis of HPV(-)OPSCC. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:1394-1401, 2023.