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1.
PLoS Pathog ; 17(1): e1009216, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33481911

RESUMO

Intracellular pathogens have evolved to utilize normal cellular processes to complete their replicative cycles. Pathogens that interface with proliferative cell signaling pathways risk infections that can lead to cancers, but the factors that influence malignant outcomes are incompletely understood. Human papillomaviruses (HPVs) predominantly cause benign hyperplasia in stratifying epithelial tissues. However, a subset of carcinogenic or "high-risk" HPV (hr-HPV) genotypes are etiologically linked to nearly 5% of all human cancers. Progression of hr-HPV-induced lesions to malignancies is characterized by increased expression of the E6 and E7 oncogenes and the oncogenic functions of these viral proteins have been widely studied. Yet, the mechanisms that regulate hr-HPV oncogene transcription and suppress their expression in benign lesions remain poorly understood. Here, we demonstrate that EGFR/MEK/ERK signaling, influenced by epithelial contact inhibition and tissue differentiation cues, regulates hr-HPV oncogene expression. Using monolayer cells, epithelial organotypic tissue models, and neoplastic tissue biopsy materials, we show that cell-extrinsic activation of ERK overrides cellular control to promote HPV oncogene expression and the neoplastic phenotype. Our data suggest that HPVs are adapted to use the EGFR/MEK/ERK signaling pathway to regulate their productive replicative cycles. Mechanistic studies show that EGFR/MEK/ERK signaling influences AP-1 transcription factor activity and AP-1 factor knockdown reduces oncogene transcription. Furthermore, pharmacological inhibitors of EGFR, MEK, and ERK signaling quash HPV oncogene expression and the neoplastic phenotype, revealing a potential clinical strategy to suppress uncontrolled cell proliferation, reduce oncogene expression and treat HPV neoplasia.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/virologia , MAP Quinases Reguladas por Sinal Extracelular/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Terapia de Alvo Molecular , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/terapia
2.
Chemotherapy ; 68(1): 35-43, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35882207

RESUMO

INTRODUCTION: Standard of care for radiosensitization in head and neck squamous cell carcinoma (HNSCC) is concurrent chemoradiotherapy (CCRT) with high-dose cisplatin. The optimal chemoradiation regimen for patients medically unfit for cisplatin is unclear. We compared our experience with concurrent cetuximab (CTX) versus other cytotoxic non-cisplatin agents. METHODS: We reviewed 53 patients between 2011 and 2017 with HNSCC treated with CCRT ineligible for cisplatin. Chemotherapy and radiotherapy treatment tolerance was evaluated in those receiving CTX versus non-CTX chemotherapy (NCC). Of the NCC regimens, the majority were carboplatin/paclitaxel and were dosed at an area under the curve (AUC) of 2 and 45-50 mg/m2, respectively. Standard radiation dosing was 70 Gray (Gy) in the definitive setting and 60-66 Gy in the postoperative setting. Patient characteristics and treatment toxicities were evaluated using categorical methods. RESULTS: Patients were well balanced overall including differences between performance status and the comorbidity score. NCC patients experienced more radiation treatment breaks (52.4% vs. 21.9%, p = 0.022), radiation delays >1 week (33.3% vs. 3.1%, p < 0.01), and chemotherapy dose-limiting toxicity (61.9% vs. 28.1%, p = 0.015) compared to CTX patients. Nutritional dependence on a PEG tube was more likely in the NCC cohort (52.4% vs. 22.6%, p = 0.027). CONCLUSION: Our results suggest decreased treatment tolerance in non-cisplatin cytotoxic chemotherapy compared to cetuximab. Further prospective study is needed to clarify optimal chemotherapy in patients unable to receive cisplatin.


Assuntos
Antineoplásicos , Cetuximab , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Antineoplásicos/efeitos adversos , Cetuximab/efeitos adversos , Quimiorradioterapia , Cisplatino/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Resultado do Tratamento
3.
Mol Carcinog ; 61(2): 173-199, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34559922

RESUMO

Cancer and the immune system share an intimate relationship. Chronic inflammation increases the risk of cancer occurrence and can also drive inflammatory mediators into the tumor microenvironment enhancing tumor growth and survival. The p38 MAPK pathway is activated both acutely and chronically by stress, inflammatory chemokines, chronic inflammatory conditions, and cancer. These properties have led to extensive efforts to find effective drugs targeting p38, which have been unsuccessful. The immediate downstream serine/threonine kinase and substrate of p38 MAPK, mitogen-activated-protein-kinase-activated-protein-kinase-2 (MK2) protects cells against stressors by regulating the DNA damage response, transcription, protein and messenger RNA stability, and motility. The phosphorylation of downstream substrates by MK2 increases inflammatory cytokine production, drives an immune response, and contributes to wound healing. By binding directly to p38 MAPK, MK2 is responsible for the export of p38 MAPK from the nucleus which gives MK2 properties that make it unique among the large number of p38 MAPK substrates. Many of the substrates of both p38 MAPK and MK2 are separated between the cytosol and nucleus and interfering with MK2 and altering this intracellular translocation has implications for the actions of both p38 MAPK and MK2. The inhibition of MK2 has shown promise in combination with both chemotherapy and radiotherapy as a method for controlling cancer growth and metastasis in a variety of cancers. Whereas the current data are encouraging the field requires the development of selective and well tolerated drugs to target MK2 and a better understanding of its effects for effective clinical use.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias , Proteínas Serina-Treonina Quinases/metabolismo , Sobrevivência Celular , Humanos , Sistema de Sinalização das MAP Quinases , Microambiente Tumoral , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Support Care Cancer ; 28(2): 827-835, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31152302

RESUMO

PURPOSE: Cross-sectional research suggests that thinking about multiple ways to reach goals (hope pathways) and the belief that one can reach them (hope agency) may be adaptive for lung cancer patients. We examined the between-person and within-person associations among aspects of hope agency and pathways thinking, daily fatigue, pain, and functional concerns (e.g., sense of independence, usefulness) among lung cancer patients during active treatment. METHODS: Data from a daily diary study were used to examine relations among hope agency, hope pathways, fatigue, pain, and functional concern in 50 patients with advanced lung cancer. Participants were accrued from one outpatient cancer center and completed the study between 2014 and 2015. RESULTS: Adjusting for covariates and the previous day's symptoms or concern, patients who engaged in higher pathways thinking reported lower daily symptoms, whereas those who engaged in higher agency thinking reported less functional concern. Within-person increases in pathways thinking were associated with less daily fatigue, pain, and functional concern; within-person increases in agency thinking were associated with less daily fatigue and pain. Models examining symptoms and concerns as predictors of hope suggested within-person increases in functional concern and fatigue and pain were related to lower agency and pathways thinking the same day. Patients with higher fatigue and pain did not report lower agency or pathways thinking, but patients with more functional concern did. CONCLUSIONS: Increases in hope pathways thinking may be associated with lower symptoms and better functioning in lung cancer patients. This suggests that it is important to determine the efficacy of interventions that emphasize the pathways the component of hope.


Assuntos
Fadiga/etiologia , Esperança/fisiologia , Neoplasias Pulmonares/complicações , Dor/etiologia , Estudos Transversais , Feminino , Humanos , Masculino
5.
Int J Cancer ; 142(8): 1702-1711, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29197088

RESUMO

Colorectal cancer (CRC) development and progression is associated with chronic inflammation. We have identified the MAPK-activated protein kinase 2 (MK2) pathway as a primary mediator of inflammation in CRC. MK2 signaling promotes production of proinflammatory cytokines IL-1ß, IL-6 and TNF-α. These cytokines have been implicated in tumor growth, invasion and metastasis. For the first time, we investigate whether MK2 inhibition can improve outcome in two mouse models of CRC. In our azoxymethane/dextran sodium sulfate (AOM/DSS) model of colitis-associated CRC, MK2 inhibitor treatment eliminated murine tumor development. Using the implanted, syngeneic murine CRC cell line CT26, we observe significant tumor volume reduction following MK2 inhibition. Tumor cells treated with MK2 inhibitors produced 80% less IL-1ß, IL-6 and TNF-α and demonstrated decreased invasion. Replenishment of downstream proinflammatory MK2-mediated cytokines (IL-1ß, IL-6 and TNF-α) to tumors led to restoration of tumor proliferation and rapid tumor regrowth. These results demonstrate the importance of MK2 in driving proinflammatory cytokine production, its relevance to in vivo tumor proliferation and invasion. Inhibition of MK2 may represent an attractive therapeutic target to suppress tumor growth and progression in patients.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Azoximetano/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Neoplasias Colorretais/induzido quimicamente , Sulfato de Dextrana/farmacologia , Feminino , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transdução de Sinais/fisiologia
6.
J Transl Med ; 15(1): 168, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28764811

RESUMO

BACKGROUND: Squamous cell carcinoma of the head and neck (HNSCC) represents an array of disease processes with a generally unfavorable prognosis. Inflammation plays an important role in tumor development and response to therapy. We performed a retrospective analysis of HNSCC patients to explore the relationship of the lymphocyte and neutrophil counts, the neutrophil-to-lymphocyte ratio (NLR) overall survival (OS), cancer-specific survival (CSS), local control (LC) and distant control (DC). MATERIALS/METHODS: All patients received definitive treatment for cancers of the oropharynx or larynx between 2006-2015. Neutrophil and lymphocyte counts were collected pre-, during-, and post-treatment. The correlations of patient, tumor, and biological factors to OS, CSS, LC and DC were assessed. RESULTS: 196 patients met our inclusion criteria; 171 patients were Stage III or IV. Median follow-up was 2.7 years. A higher neutrophil count at all treatment time points was predictive of poor OS with the pre-treatment neutrophil count and overall neutrophil nadir additionally predictive of DC. Higher pre-treatment and overall NLR correlated to worse OS and DC, respectively. CONCLUSION: A higher pre-treatment neutrophil count correlates to poor OS, CSS and DC. Lymphocyte counts were not found to impact survival or tumor control. Higher pre-treatment NLR is prognostic of poor OS.


Assuntos
Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Neutrófilos/patologia , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Laríngeas/sangue , Contagem de Linfócitos , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Orofaríngeas/sangue , Prognóstico , Análise de Sobrevida
7.
Rep Pract Oncol Radiother ; 22(5): 389-395, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28808428

RESUMO

AIM: To present our experience comparing cisplatin- and cetuximab-based radiotherapy for locally-advanced head and neck squamous cell carcinoma. BACKGROUND: The comparative effectiveness of cisplatin-based chemoradiotherapy (CRT) versus cetuximab-based bioradiotherapy (BRT) for locally-advanced head and neck squamous cell carcinoma (LAHNSCC) continues to be explored. MATERIALS AND METHODS: Outcomes of LAHNSCC patients treated with CRT (125) or BRT (34) at two institutions were compared retrospectively, with attention to overall survival (OS), cancer-specific survival (CSS), locoregional control (LRC), and distant control (DC). Univariate analysis (UVA) using Cox regression was performed to explore the association of intervention with survival and disease control, and multivariate (MVA) Cox regression was then performed to assess the association of intervention with survival. RESULTS: There were significant baseline differences between the CRT and BRT groups with respect to age, race, performance status, N-classification, tobacco history, and human papillomavirus status. UVA demonstrated inferiority of BRT versus CRT with respect to both OS (hazard ratio [HR] 2.19, 95% confidence interval [95%CI] 1.03-4.63, p = 0.04) and CSS (HR 3.33, 95%CI 1.42-7.78, p < 0.01), but non-significantly different outcomes in LRC (HR 0.99, 95%CI 0.37-2.61, p = 0.98) and DC (HR 2.01, 95%CI 0.78-5.37, p = 0.14). On MVA, there was no significant OS difference between interventions (HR 1.19, 95%CI 0.42-3.35, p = 0.74); there were too few events for the other outcomes to draw meaningful conclusions with MVA. CONCLUSIONS: In our retrospective analysis, patients undergoing CRT experienced improved OS and CSS over those receiving BRT; however, disease control did not significantly differ. These findings may inform management of LAHNSCC patients.

8.
Future Oncol ; 12(23): 2713-2727, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27467543

RESUMO

In recent years, the emergence of the oligometastatic state has called into question whether patients found to have a limited or low metastatic tumor burden may benefit from locally ablative therapy (LAT). In the past two decades, stereotactic body radiation therapy has been increasingly used to safely deliver LAT and provide high local control in nonoperable non-small-cell lung cancer patients. Mostly retrospective analyses suggest that using LAT for oligometastatic disease in non-small-cell lung cancer offers excellent local control and may provide an improvement in progression-free survival. Any meaningful improvement in cancer-specific survival remains debatable. We examine the role of integrating LAT in this patient population and the rationale behind its use in combination with targeted therapy and immunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Radiocirurgia/métodos , Neoplasias das Glândulas Suprarrenais/secundário , Neoplasias das Glândulas Suprarrenais/terapia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Análise Custo-Benefício , Progressão da Doença , Genes erbB-1 , Humanos , Imunoterapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Proteínas de Fusão Oncogênica/genética , Seleção de Pacientes , Prognóstico , Radiocirurgia/efeitos adversos , Radiocirurgia/economia , Translocação Genética , Resultado do Tratamento
9.
Explor Target Antitumor Ther ; 5(1): 108-119, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468824

RESUMO

Head and neck cancer (HNC) is a challenging disease that lacks effective treatment, particularly in the cases that spread locoregionally and metastasize distantly, dramatically reducing patient survival rates. Expanding the understanding of the mechanisms of the metastatic cascade is critical for creating more effective therapeutics that improve outcomes for HNC patients. A true grasp of cancer metastasis requires the consideration of all cell types that contribute to the inflammatory HNC microenvironment as drivers of this process. More emphasis now is being placed on exploring the roles of the different immune cells in cancer control, tumorigenesis and metastasis. Myeloid cells are the most numerous immune cell types in the body, and they are actively recruited and reprogrammed by tumor cells to behave in a variety of ways. These cells are remarkably diverse in phenotype and function, and the part they play in tumor spread greatly differs based on the cell type. This review will focus on summarizing the roles of macrophages, neutrophils, myeloid derived suppressor cells (MDSCs), and dendritic cells (DCs) in driving HNC metastasis by examining the current knowledge base and offering potential new routes through which to target and treat this deadly process.

10.
Infect Dis Model ; 9(1): 214-223, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38293686

RESUMO

Introduction: The transmission dynamics of the recent mpox outbreak highlights the lack of infrastructure available to rapidly respond to novel STI outbreaks, of which Asia and Oceania remains particularly susceptible. Here, we simulate outbreaks in this setting and propose the use of pre-emptive vaccination within the men who have sex with men (MSM) community before the arrival and establishment of the virus. Materials and methods: Using data driven heterogeneous sexual contact networks, we simulated outbreaks of mpox in Singapore, Hong Kong, and Sydney. An individual based SEIR compartmental model was used to simulate epidemic trajectories and the impact of different vaccination uptakes was assessed in their ability to avert or suppress outbreaks upon the arrival of mpox within the MSM populations. Results: The highly dense sexual networks of Singapore and Sydney experience rapid outbreaks, with infection peaks occurring at day 41 and 23 respectively, compared to Hong Kong which occurs at day 77. Across the simulations with no vaccination, 68.2%-89.7% of the MSM community will become infected with mpox across the different cities, over a simulation period of 1 year. By implementing vaccination strategies, the infection rate across the cities can be reduced to as low as 3.1% of the population (range: 3.1%-82.2%) depending on the implementation and uptake of the vaccine. Vaccination is also extremely effective in slowing the start of the epidemic, delaying the epidemic peak by 36-50 days in Hong Kong, or even preventing the outbreak of mpox. Discussion: With extremely dense and well-connected sexual contact networks, where 65.2%-83.2% of the population are connected to a super-spreader in the different contact networks, pre-emptive or immediate vaccination upon identification of the first case is strongly recommended to help better manage the outbreak of mpox and prevent potential straining of healthcare systems.

11.
Front Oncol ; 14: 1421869, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39099699

RESUMO

Background: Proton minibeam radiation therapy (pMBRT) can deliver spatially fractionated dose distributions with submillimeter resolution. These dose distributions exhibit significant heterogeneity in both depth and lateral directions. Accurate characterization of pMBRT doses requires dosimetry devices with high spatial resolution and a wide dynamic range. Furthermore, the dependency of dosimetric measurements on Linear Energy Transfer (LET), as observed in conventional proton therapy, is also present in pMBRT depth dose measurements. Purpose: This work demonstrates the process of performing comprehensive dosimetric measurements to characterize the pMBRT collimator on a clinical single-gantry proton machine, utilizing commercially available dosimetry devices. Methods: The minibeam collimator is designed to be mounted on the clinical nozzle as a beam-modifying accessory. Three collimators, each with a slit opening of 0.4 mm, are thoroughly evaluated. The center-to-center (c-t-c) distances of the slits for these collimators are 2.8 mm, 3.2 mm, and 4.0 mm, respectively. High spatial resolution dosimetry devices are essential for PMBRT dose characterizations. To meet this requirement, two-dimensional (2D) dose measurement devices, Gafchromic films, are used to measure lateral profiles at various depths. Films are also used for depth dose profile measurements in solid water. Additionally, high-resolution point dose detectors, microDiamond, and Razor diode detectors are employed for lateral profile measurements at various depths. Percent depth dose (PDD) measurements of pMBRT in solid water, with various proton energies, collimators, and air gaps, are performed using Gafchromic films. The film's LET dependency for proton beams is corrected to ensure accurate pMBRT PDD measurements. The Monte Carlo simulation tool TOPAS is utilized to compare and validate all experimental measurements. Results: At depths where LET is not a concern, film dose measurements were consistent with microDiamond and Razor diode point measurements. The point detectors need to be orientated with the thin side aligned to the incoming beam. Comparison of the lateral dose profiles extracted from TOPAS simulations, films, microDiamond, and Razor diode detectors shows a passing rate exceeding 98% in 1D gamma analysis at 3% 0.1 mm criteria.However, when the microDiamond detector is orientated to face the pMBRT beam, its spatial resolution may not be sufficient to capture the peak and valley dose accurately. Nevertheless, an accuracy within 2% can still be achieved when comparing the average dose. The PDD measurements show that the peak valley dose ratio (PVDR) of pMBRT can be altered at different depths with different air gaps using the same collimator or different collimators of different c-t-c distances. Conclusion: Our study demonstrates that comprehensive dose measurements for pMBRT can be conducted using standard clinical dose measurement devices. These measurements are indispensable for guiding and ensuring accurate dose reporting in pre-clinical studies using the pMBRT technique.

12.
Med Phys ; 51(6): 3995-4006, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642468

RESUMO

BACKGROUND: Minibeam represents a preclinical spatially fractionated radiotherapy modality with great translational potential. The advantage lies in its high therapeutic index (compared to GRID and LATTICE) and ability to treat at greater depth (compared to microbeam). Proton minibeam radiotherapy (pMBRT) is a synergy of proton and minibeam. While the single-gantry proton facility has gained popularity due to its affordability and compact design, it often has limited beam time available for research purposes. Conversely, given the current requirement of pMBRT on specific minibeam hardware collimators, necessitates a reproducible and fast setup to minimize pMBRT treatment time and streamline the switching time between pMBRT and conventional treatment for clinically translation. PURPOSE: The contribution of this work is the development and characterization of the first pMBRT system tailored for single-gantry proton facility. The system allows for efficient and reproducible plug-and-play setup, achievable within minutes. METHODS: The single room pMBRT system is constructed based on IBA ProteusONE proton machine. The end of nozzle is attached with beam modifying accessories though an accessory drawer. A small snout is attached to the accessory drawer and used to hold apertures and range shifters. The minibeam aperture consists of two components: a fitting ring and an aperture body. Three minibeam apertures were manufactured. The first-generation apertures underwent qualitatively analysis with film, and the second generation aperture underwent more comprehensive quantitative measurement. The reproducibility of the setup is accessed, and the film measurements are performed to characterize the pMBRT system in cross validation with Monte Carlo (MC) simulations. RESULTS: We presented initial results of large field pMBRT aperture and the film measurements indicates the effect of source-to-isocenter distance = 930 cm in Y proton scanning direction. Consistent with TOPAS MC simulation, the dose uniformity of pMBRT field <2 cm is demonstrated to be better than 2%, rendering its suitability for pre-clinical studies. Subsequently, we developed the second generation of aperture with five slits and characterized the aperture with film dosimetry studies and compared the results to the benchmark MC. Comprehensive film measurements were also performed to evaluate the effect of divergence, air gap and gantry-angle dependency and repeatability and revealing a consistent performance within 5%. Furthermore, the 2D gamma analysis indicated a passing rate exceeding 99% using 3% dose difference and 0.2 mm distance agreement criteria. We also establish the peak valley dose ratio and the depth dose profile measurements, and the results are within 10% from MC simulation. CONCLUSIONS: We have developed the first pMBRT system tailored for a single-gantry proton facility, which has demonstrated accuracy in benchmark with MC simulations, and allows for efficient plug-and-play setup, emphasizing efficiency.


Assuntos
Desenho de Equipamento , Terapia com Prótons , Terapia com Prótons/instrumentação , Método de Monte Carlo , Prótons , Dosagem Radioterapêutica
13.
Med Phys ; 51(8): 5190-5203, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38873848

RESUMO

BACKGROUND: Although the FLASH radiotherapy (FLASH) can improve the sparing of organs-at-risk (OAR) via the FLASH effect, it is generally a tradeoff between the physical dose coverage and the biological FLASH coverage, for which the concept of FLASH effective dose (FED) is needed to quantify the net improvement of FLASH, compared to the conventional radiotherapy (CONV). PURPOSE: This work will develop the first-of-its-kind treatment planning method called simultaneous dose and dose rate optimization via dose modifying factor modeling (SDDRO-DMF) for proton FLASH that directly optimizes FED. METHODS: SDDRO-DMF models and optimizes FED using FLASH dose modifying factor (DMF) models, which can be classified into two categories: (1) the phenomenological model of the FLASH effect, such as the FLASH effectiveness model (FEM); (2) the mechanistic model of the FLASH radiobiology, such as the radiolytic oxygen depletion (ROD) model. The general framework of SDDRO-DMF will be developed, with specific DMF models using FEM and ROD, as a demonstration of general applicability of SDDRO-DMF for proton FLASH via transmission beams (TB) or Bragg peaks (BP) with single-field or multi-field irradiation. The FLASH dose rate is modeled as pencil beam scanning dose rate. The solution algorithm for solving the inverse optimization problem of SDDRO-DMF is based on iterative convex relaxation method. RESULTS: SDDRO-DMF is validated in comparison with IMPT and a state-of-the-art method called SDDRO, with demonstrated efficacy and improvement for reducing the high dose and the high-dose volume for OAR in terms of FED. For example, in a SBRT lung case of the dose-limiting factor that the max dose of brachial plexus should be no more than 26 Gy, only SDDRO-DMF met this max dose constraint; moreover, SDDRO-DMF completely eliminated the high-dose (V70%) volume to zero for CTV10mm (a high-dose region as a 10 mm ring expansion of CTV). CONCLUSION: We have proposed a new proton FLASH optimization method called SDDRO-DMF that directly optimizes FED using phenomenological or mechanistic models of DMF, and have demonstrated the efficacy of SDDO-DMF in reducing the high-dose volume or/and the high-dose value for OAR, compared to IMPT and a state-of-the-art method SDDRO.


Assuntos
Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Planejamento da Radioterapia Assistida por Computador/métodos , Doses de Radiação , Humanos , Órgãos em Risco/efeitos da radiação , Terapia com Prótons/métodos , Modelos Biológicos
14.
Clin Lung Cancer ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39242330

RESUMO

BACKGROUND: Immunotherapy in combination with chemotherapy is first-line treatment for patients with extensive-stage small-cell lung cancer (ES-SCLC). Growing evidence suggests that radiation, specifically stereotactic body radiation therapy (SBRT), may enhance the immunogenic response as well as cytoreduce tumor burden. The primary objective of the study is to determine the progression free survival for patients with newly diagnosed ES-SCLC treated with combination multisite SBRT and chemo-immunotherapy (carboplatin, etoposide, and durvalumab). METHODS: This is a multicenter, single arm, phase 2 study. Patients with treatment-naïve, ES-SCLC will be eligible for this study. Patients will receive durvalumab 1500mg IV q3w, carboplatin AUC 5 to 6 mg/mL q3w, and etoposide 80 to 100 mg/m2 on days 1 to 3 q3w for four cycles, followed by durvalumab 1500mg IV q4w until disease progression or unacceptable toxicity. Ablative radiation will be delivered 1 to 4 extracranial sites in 3 or 5 fractions, determined by location, during cycle 2. The primary endpoint is progression-free survival, measured from day 1 of chemoimmunotherapy. Secondary endpoints include grade ≥3 toxicity by CTCAE v5.0 within three months of RT, overall survival, response rate, time to second line systemic therapy, and time to new distant progression. CONCLUSIONS: Now that immunotherapy is an established part of ES-SCLC management, it is important to further optimize its use and effect. This study will investigate the progression-free survival of combined SBRT and chemo-immunotherapy in patients with ES-SCLC. In addition, the data from this study may further inform the immunogenic role of SBRT with chemo-immunotherapy, as well as identify clinical, biological, or radiomic prognostic features.

15.
Laryngoscope ; 134(8): 3645-3655, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38436503

RESUMO

OBJECTIVE: To determine differences in post-treatment QoL across treatment settings in patients receiving adjuvant radiation therapy for head and neck squamous cell carcinoma (HNSCC). METHODS: This was a prospective observational cohort study of patients with HNSCC initially evaluated in a head and neck surgical oncologic and reconstructive clinic at an academic medical center (AMC). Participants were enrolled prior to treatment in a prospective registry collecting demographic, social, and clinical data. Physical and social-emotional QoL (phys-QoL and soc-QoL, respectively) was measured using the University of Washington-QoL questionnaire at pre-treatment and post-treatment visits. RESULTS: A cohort of 177 patients, primarily male and White with an average age of 61.2 ± 11.2 years, met inclusion criteria. Most patients presented with oral cavity tumors (n = 132, 74.6%), had non-HPV-mediated disease (n = 97, 61.8%), and were classified as Stage IVa (n = 72, 42.8%). After controlling for covariates, patients treated at community medical centers (CMCs) reported a 7.15-point lower phys-QoL compared with those treated at AMCs (95% CI: -13.96 to -0.35, p = 0.040) up to 12 months post-treatment. Additionally, patients who were treated at CMCs had a 5.77-point (-11.86-0.31, p = 0.063) lower soc-QoL score compared with those treated at an AMC, which was not statistically significant. CONCLUSION: This study revealed that HNSCC patients treated with radiation at AMCs reported significantly greater phys-QoL in their first-year post-treatment compared to those treated at CMCs, but soc-QoL did not differ significantly. Further observational studies are needed to explore potential factors, including treatment planning and cancer resource engagement, behind disparities between AMCs and CMCs. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:3645-3655, 2024.


Assuntos
Neoplasias de Cabeça e Pescoço , Qualidade de Vida , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , Radioterapia Adjuvante , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/psicologia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/psicologia , Idoso , Inquéritos e Questionários
16.
PLoS Negl Trop Dis ; 17(12): e0011763, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38150471

RESUMO

BACKGROUND: Transmission intensity for mosquito-borne diseases are highly heterogenous and multi-factorial. Understanding risk factors associated to disease transmission allow the optimization of vector control. This study sets out to understand and compare the combined anthropogenic and environmental risk factors of four major mosquito-borne diseases, dengue, malaria, chikungunya and Japanese encephalitis in Thailand. METHODS: An integrated analysis of mosquito-borne diseases, meteorological and ambient air pollutants of 76 provinces of Thailand was conducted over 2003-2021. We explored the use of generalized linear models and generalized additive models to consider both linear and non-linear associations between meteorological factors, ambient air pollutants and mosquito-borne disease incidence. Different assumptions on spatio-temporal dependence and nonlinearity were considered through province-specific and panel models, as well as different spline functions. Disease-specific model evidence was assessed to select best-fit models for epidemiological inference downstream. RESULTS: Analyses indicated several findings which can be generally applied to all diseases explored: (1) higher AH above mean values was positively associated with disease case counts (2) higher total precipitation above mean values was positively associated with disease case counts (3) extremely high temperatures were negatively associated with disease case counts (4) higher SO2 and PM2.5 surface concentrations were negatively associated with disease case counts. However, the relationships between disease and RH, non-extreme temperatures and CO surface concentration were more mixed, with directions of associations changing across the different diseases considered. CONCLUSIONS: This study found protective and enhancing effects of meteorological and ambient air pollutant factors on mosquito-borne diseases burdens in Thailand. Further studies should employ these factors to understand and predict risk factors associated with mosquito-borne disease transmission.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Doenças Transmitidas por Mosquitos , Animais , Humanos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Ambientais/análise , Tailândia/epidemiologia , Temperatura
17.
Otolaryngol Head Neck Surg ; 169(1): 69-75, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35917167

RESUMO

OBJECTIVE: To evaluate the effect of histopathologic skin invasion on 2- and 5-year disease-free survival (DFS) and overall survival (OS) in patients treated with primary surgery for locally advanced oral cavity squamous cell carcinoma (OCSCC). STUDY DESIGN: A retrospective case-control study was performed comparing previously untreated patients with pT4a OCSCC with and without skin invasion. SETTING: Academic medical center. METHODS: Propensity score-matched cohorts were derived by age, sex, surgical margins, pathologic N classification, adjuvant treatment, and primary tumor site. The Kaplan-Meier method was used to evaluate 2- and 5-year OS and DFS, which were compared between cohorts via the log rank (Mantel-Cox) test statistic. RESULTS: Overall 25 patients were identified to have pathologic skin invasion, and 50 were selected for the matched control group. OS was significantly lower for patients with skin invasion as compared with controls at 2 years (30.8% vs 53.3%, P = .018) and 5 years (16.6% vs 42.2%, P = .01). DFS was significantly lower for patients with skin invasion vs controls at 2 years (23.7% vs 47.7, P = .037) and 5 years (15.8% vs 41.4%, P = .024). CONCLUSION: Histopathologic skin invasion in OCSCC is associated with dismal prognosis in patients who underwent primary surgical treatment. OS outcomes for patients with skin invasion are comparable to survival of patients with recurrent/metastatic disease and T4N2 disease.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Estudos Retrospectivos , Estudos de Casos e Controles , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia
18.
Otolaryngol Head Neck Surg ; 169(4): 928-937, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36939526

RESUMO

OBJECTIVE: In patients with head and neck squamous cell carcinoma (HNSCC), initiating postoperative radiotherapy (PORT) greater than 42 days after surgery is associated with a higher risk of poor survival outcomes. Social support has been shown to modulate behaviors related to care-seeking and treatment adherence. In this study, we sought to determine the relationship between social support metrics and PORT delays. STUDY DESIGN: Prospective cohort study. SETTING: Single tertiary medical center. METHODS: Patients with HNSCC who underwent primary surgical excision requiring PORT were prospectively enrolled. Patient-perceived social support metrics were assessed using the Medical Outcomes Study Social Support Survey (MOS-SSS) at initial presurgical evaluation. Associations with PORT delays were evaluated via univariable and multivariable logistic regression analysis. RESULTS: A total of 111 patients met the inclusion criteria for the study. An additional 28 patients were recommended to receive PORT but did not initiate treatment and were included for secondary analysis. All four subscales of the MOS-SSS (positive social interaction, affectionate support, tangible support, and emotional/informational support) were significantly associated with PORT initiation delays on univariable analysis. On multivariable analysis, the overall MOS-SSS score (odds ratio [OR] 2.08, 1.15-4.35, p = .028) was significantly associated with PORT initiation delays. On secondary analysis, lower tangible support was associated with a lack of PORT initiation (OR 1.63, 1.05-2.54, p = .028). CONCLUSION: Social support metrics were significantly associated with PORT delays, which may help promote tighter scheduling and closer monitoring of high-risk patients.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Radioterapia Adjuvante , Carcinoma de Células Escamosas/patologia , Estudos Prospectivos , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Apoio Social , Estudos Retrospectivos
19.
JAMA Otolaryngol Head Neck Surg ; 149(6): 477-484, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37079327

RESUMO

Importance: Timely initiation of postoperative radiation therapy (PORT) is associated with reduced recurrence rates and improved overall survival in patients with head and neck squamous cell carcinoma (HNSCC). Measurement of the association of social-ecological variables with PORT delays is lacking. Objective: To assess individual and community-level factors associated with PORT delay among patients with HNSCC. Design, Setting, and Participants: This prospective cohort study carried out between September 2018 and June 2022 included adults with untreated HNSCC who were enrolled in a prospective registry at a single academic tertiary medical center. Demographic information and validated self-reported measures of health literacy were obtained at baseline visits. Clinical data were recorded, and participant addresses were used to calculate the area deprivation index (ADI), a measure of community-level social vulnerability. Participants receiving primary surgery and PORT were analyzed. Univariable and multivariable regression analysis was performed to identify risk factors for PORT delays. Exposures: Surgical treatment and PORT. Main Outcomes and Measures: The primary outcome was PORT initiation delay (>42 days from surgery). Risk of PORT initiation delay was evaluated using individual-level (demographic, health literacy, and clinical data) and community-level information (ADI and rural-urban continuum codes). Results: Of 171 patients, 104 patients (60.8%) had PORT delays. Mean (SD) age of participants was 61.0 (11.2) years, 161 were White (94.2%), and 105 were men (61.4%). Insurance was employer-based or public among 65 (38.5%) and 75 (44.4%) participants, respectively. Mean (SD) ADI (national percentile) was 60.2 (24.4), and 71 (41.8%) resided in rural communities. Tumor sites were most commonly oral cavity (123 [71.9%]), with 108 (63.5%) classified as stage 4 at presentation. On multivariable analysis, a model incorporating individual-level factors with health literacy in addition to community-level factors was most predictive of PORT delay (AOC= 0.78; R2, 0.18). Conclusions and Relevance: This cohort study provides a more comprehensive assessment of predictors of PORT delays that include health literacy and community-level measures. Predictive models that incorporate multilevel measures outperform models with individual-level factors alone and may guide precise interventions to decrease PORT delay for at-risk patients with HNSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Masculino , Adulto , Humanos , Pessoa de Meia-Idade , Feminino , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia
20.
J Clin Oncol ; 41(5): 1132-1146, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36521102

RESUMO

PURPOSE: To provide evidence-based recommendations for practicing physicians and other health care providers on immunotherapy and biomarker testing for head and neck cancers. METHODS: ASCO convened an Expert Panel of medical oncology, surgical oncology, radiation oncology, radiology, pathology, and patient advocacy experts to conduct a literature search, including systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2000 through 2022. Outcomes of interest included survival, overall response, and locoregional control. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations. RESULTS: The literature search identified 28 relevant studies to inform the evidence base for this guideline. RECOMMENDATIONS: When possible, evidence-based recommendations were developed to address biomarker testing, first-line treatment regimens based on programmed death ligand-1 scores, immunotherapy in platinum-refractory recurrent or metastatic head and neck squamous cell carcinoma, immunotherapy in nasopharyngeal carcinoma, and radiation therapy in combination with immunotherapy for treatment of local recurrence.Additional information is available at www.asco.org/head-neck-cancer-guidelines.


Assuntos
Neoplasias de Cabeça e Pescoço , Humanos , Biomarcadores , Imunoterapia , Estudos Prospectivos , Estudos Retrospectivos
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