Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
Radiother Oncol ; 193: 110143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341098

RESUMO

INTRODUCTION: Neurocognitive impairment from inadvertent brain irradiation is common following intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). This study aimed to determine the prevalence, pattern, and radiation dose-toxicity relationship of this late complication. MATERIALS AND METHODS: We undertook a cross-sectional study of 190 post-IMRT NPC survivors. Neurocognitive function was screened using the Montreal Cognitive Assessment-Hong Kong (HK-MoCA). Detailed assessments of eight distinct neurocognitive domains were conducted: intellectual capacity (WAIS-IV), attention span (Digit Span and Visual Spatial Span), visual memory (Visual Reproduction Span), verbal memory (Auditory Verbal Learning Test), processing speed (Color Trail Test), executive function (Stroop Test), motor dexterity (Grooved Pegboard Test) and language ability (Verbal Fluency Test). The mean percentiles and Z-scores were compared with normative population data. Associations between radiation dose and brain substructures were explored using multivariable logistic regression. RESULTS: The median post-IMRT interval was 7.0 years. The prevalence of impaired HK-MoCA was 25.3 % (48/190). Among the participants, 151 (79.4 %) exhibited impairments in at least one neurocognitive domain. The predominantly impaired domains included verbal memory (short-term: mean Z-score, -0.56, p < 0.001; long-term: mean Z-score, -0.70, p < 0.001), processing speed (basic: mean Z-score, -1.04, p < 0.001; advanced: mean Z-score, -0.38, p < 0.001), executive function (mean Z-score, -1.90, p < 0.001), and motor dexterity (dominant hand: mean Z-score, -0.97, p < 0.001). Radiation dose to the whole brain, hippocampus, and temporal lobe was associated with impairments in executive function, verbal memory, processing speed, and motor dexterity. CONCLUSIONS: Neurocognitive impairment is prevalent and profound in post-IMRT NPC survivors. Cognitive assessment and rehabilitation should be considered part of survivorship care.


Assuntos
Neoplasias Nasofaríngeas , Lesões por Radiação , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Nasofaríngeas/radioterapia , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Transversais , Função Executiva , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Testes Neuropsicológicos
2.
J Natl Cancer Inst ; 116(5): 665-672, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38171488

RESUMO

BACKGROUND: Although contrast-enhanced magnetic resonance imaging (MRI) detects early-stage nasopharyngeal carcinoma (NPC) not detected by endoscopic-guided biopsy (EGB), a short contrast-free screening MRI would be desirable for NPC screening programs. This study evaluated a screening MRI in a plasma Epstein-Barr virus (EBV)-DNA NPC screening program. METHODS: EBV-DNA-screen-positive patients underwent endoscopy, and endoscopy-positive patients underwent EGB. EGB was negative if the biopsy was negative or was not performed. Patients also underwent a screening MRI. Diagnostic performance was based on histologic confirmation of NPC in the initial study or during a follow-up period of at least 2 years. RESULTS: The study prospectively recruited 354 patients for MRI and endoscopy; 40/354 (11.3%) endoscopy-positive patients underwent EGB. Eighteen had NPC (5.1%), and 336 without NPC (94.9%) were followed up for a median of 44.8 months. MRI detected additional NPCs in 3/18 (16.7%) endoscopy-negative and 2/18 (11.1%) EGB-negative patients (stage I/II, n = 4; stage III, n = 1). None of the 24 EGB-negative patients who were MRI-negative had NPC. MRI missed NPC in 2/18 (11.1%), one of which was also endoscopy-negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MRI, endoscopy, and EGB were 88.9%, 91.1%, 34.8%, 99.4%, and 91.0%; 77.8%, 92.3%, 35.0%, 98.7%, and 91.5%; and 66.7%, 92.3%, 31.6%, 98.1%, and 91.0%, respectively. CONCLUSION: A quick contrast-free screening MRI complements endoscopy in NPC screening programs. In EBV-screen-positive patients, MRI enables early detection of NPC that is endoscopically occult or negative on EGB and increases confidence that NPC has not been missed.


Assuntos
Detecção Precoce de Câncer , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Imageamento por Ressonância Magnética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Neoplasias Nasofaríngeas/virologia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/patologia , Masculino , Pessoa de Meia-Idade , Feminino , Imageamento por Ressonância Magnética/métodos , Detecção Precoce de Câncer/métodos , Adulto , Herpesvirus Humano 4/isolamento & purificação , Carcinoma Nasofaríngeo/virologia , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/patologia , Estudos Prospectivos , Idoso , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , DNA Viral/sangue , Carcinoma/diagnóstico por imagem , Carcinoma/virologia , Carcinoma/diagnóstico , Carcinoma/patologia , Sensibilidade e Especificidade , Endoscopia/métodos , Estadiamento de Neoplasias , Programas de Rastreamento/métodos , Meios de Contraste/administração & dosagem
3.
Infect Dis Model ; 8(1): 107-121, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36632179

RESUMO

Virus evolution is a common process of pathogen adaption to host population and environment. Frequently, a small but important fraction of virus mutations are reported to contribute to higher risks of host infection, which is one of the major determinants of infectious diseases outbreaks at population scale. The key mutations contributing to transmission advantage of a genetic variant often grow and reach fixation rapidly. Based on classic epidemiology theories of disease transmission, we proposed a mechanistic explanation of the process that between-host transmission advantage may shape the observed logistic curve of the mutation proportion in population. The logistic growth of mutation is further generalized by incorporating time-varying selective pressure to account for impacts of external factors on pathogen adaptiveness. The proposed model is implemented in real-world data of COVID-19 to capture the emerging trends and changing dynamics of the B.1.1.7 strains of SARS-CoV-2 in England. The model characterizes and establishes the underlying theoretical mechanism that shapes the logistic growth of mutation in population.

4.
NEJM Evid ; 2(7): EVIDoa2200309, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38320164

RESUMO

BACKGROUND: We previously conducted a prospective study to show that nasopharyngeal cancer (NPC) screening with circulating Epstein­Barr virus (EBV) DNA analysis can improve survival. However, the long-term significance of positive results in individuals without cancer was unclear. METHODS: We conducted a second-round screening at a median of 43 months after the initial screening. Participants with detectable plasma EBV DNA were retested in 4 weeks, and those with persistently positive results were investigated with nasal endoscopy and magnetic resonance imaging. RESULTS: Of the 20,174 volunteers who participated in the first-round screening, 17,838 (88.6%) were rescreened. Among them, 423 (2.37%) had persistently detectable plasma EBV DNA. Twenty-four patients were identified as having NPC. A significantly higher proportion of patients had stage I/II cancer than in a historical cohort (67% vs. 20%; chi-square test, P<0.001), and they had superior 3-year progression-free survival (100% vs. 78.8%). Compared with participants with undetectable plasma EBV DNA in the first round of screening, participants with transiently and persistently positive results in the first round were more likely to have a cancer identified in the second round, with relative risks of 4.4 (95% confidence interval, 1.3 to 15.0) and 16.8 (95% confidence interval, 5.7 to 49.6), respectively. CONCLUSIONS: Individuals with detectable plasma EBV DNA but without an immediately identifiable NPC were more likely to have the cancer identified in another round of screening performed 3 to 5 years later. (Funded by Kadoorie Charitable Foundation and others; ClinicalTrials.gov number, NCT02063399.)


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico , Herpesvirus Humano 4/genética , Prognóstico , DNA Viral
5.
Public Health Genomics ; : 1-4, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986485

RESUMO

During coronavirus disease 2019 (COVID-19) pandemic, the genetic mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurred frequently. Some mutations in the spike protein are considered to promote transmissibility of the virus, while the mutation patterns in other proteins are less studied and may also be important in understanding the characteristics of SARS-CoV-2. We used the sequencing data of SARS-CoV-2 strains in California to investigate the time-varying patterns of the evolutionary genetic distance. The accumulative genetic distances were quantified across different time periods and in different viral proteins. The increasing trends of genetic distance were observed in spike protein (S protein), the RNA-dependent RNA polymerase (RdRp) region and nonstructural protein 3 (nsp3) of open reading frame 1 (ORF1), and nucleocapsid protein (N protein). The genetic distances in ORF3a, ORF8, and nsp2 of ORF1 started to diverge from their original variants after September 2020. By contrast, mutations in other proteins appeared transiently, and no evident increasing trend was observed in the genetic distance to the original variants. This study presents distinct patterns of the SARS-CoV-2 mutations across multiple proteins from the aspect of genetic distance. Future investigation shall be conducted to study the effects of accumulative mutations on epidemics characteristics.

6.
Infect Genet Evol ; 97: 105162, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34843993

RESUMO

The circulation of SARS-CoV-2 Delta (i.e., B.1.617.2) variants challenges the pandemic control. Our analysis showed that in the United Kingdom (UK), the reported case fatality ratio (CFR) decreased from May to July 2021 for non-Delta variant, whereas the decreasing trends of the CFR of Delta variant appeared weak and insignificant. The association between vaccine coverage and CFR might be stratified by different circulating variants. Due to the limitation of ecological study design, the interpretation of our results should be treated with caution.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2/patogenicidade , Cobertura Vacinal/estatística & dados numéricos , COVID-19/mortalidade , COVID-19/transmissão , Monitoramento Epidemiológico , Humanos , Mortalidade/tendências , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/imunologia , Fatores de Tempo , Reino Unido/epidemiologia
7.
BMC Infect Dis ; 21(1): 1039, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620109

RESUMO

BACKGROUND: The COVID-19 pandemic poses serious threats to global health, and the emerging mutation in SARS-CoV-2 genomes, e.g., the D614G substitution, is one of the major challenges of disease control. Characterizing the role of the mutation activities is of importance to understand how the evolution of pathogen shapes the epidemiological outcomes at population scale. METHODS: We developed a statistical framework to reconstruct variant-specific reproduction numbers and estimate transmission advantage associated with the mutation activities marked by single substitution empirically. Using likelihood-based approach, the model is exemplified with the COVID-19 surveillance data from January 1 to June 30, 2020 in California, USA. We explore the potential of this framework to generate early warning signals for detecting transmission advantage on a real-time basis. RESULTS: The modelling framework in this study links together the mutation activity at molecular scale and COVID-19 transmissibility at population scale. We find a significant transmission advantage of COVID-19 associated with the D614G substitution, which increases the infectivity by 54% (95%CI: 36, 72). For the early alarming potentials, the analytical framework is demonstrated to detect this transmission advantage, before the mutation reaches dominance, on a real-time basis. CONCLUSIONS: We reported an evidence of transmission advantage associated with D614G substitution, and highlighted the real-time estimating potentials of modelling framework.


Assuntos
COVID-19 , Genoma Viral , SARS-CoV-2 , COVID-19/virologia , Humanos , Funções Verossimilhança , Mutação , Pandemias , SARS-CoV-2/genética
8.
R Soc Open Sci ; 8(9): 201867, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34540238

RESUMO

The novel coronavirus disease 2019 (COVID-19) has spread worldwide and threatened human life. Diagnosis is crucial to contain the spread of SARS-CoV-2 infections and save lives. Diagnostic tests for COVID-19 have varying sensitivity and specificity, and the false-negative results would have substantial consequences to patient treatment and pandemic control. To detect all suspected infections, multiple testing is widely used. However, it may be challenging to build an assertion when the testing results are inconsistent. Considering the situation where there is more than one diagnostic outcome for each subject, we proposed a Bayesian probabilistic framework based on the sensitivity and specificity of each diagnostic method to synthesize a posterior probability of being infected by SARS-CoV-2. We demonstrated that the synthesized posterior outcome outperformed each individual testing outcome. A user-friendly web application was developed to implement our analytic framework with free access via http://www2.ccrb.cuhk.edu.hk/statgene/COVID_19/. The web application enables the real-time display of the integrated outcome incorporating two or more tests and calculated based on Bayesian posterior probability. A simulation-based assessment demonstrated higher accuracy and precision of the Bayesian probabilistic model compared with a single-test outcome. The online tool developed in this study can assist physicians in making clinical evaluations by effectively integrating multiple COVID-19 tests.

10.
Viruses ; 13(4)2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33918060

RESUMO

As COVID-19 is posing a serious threat to global health, the emerging mutation in SARS-CoV-2 genomes, for example, N501Y substitution, is one of the major challenges against control of the pandemic. Characterizing the relationship between mutation activities and the risk of severe clinical outcomes is of public health importance for informing the healthcare decision-making process. Using a likelihood-based approach, we developed a statistical framework to reconstruct a time-varying and variant-specific case fatality ratio (CFR), and to estimate changes in CFR associated with a single mutation empirically. For illustration, the statistical framework is implemented to the COVID-19 surveillance data in the United Kingdom (UK). The reconstructed instantaneous CFR gradually increased from 1.0% in September to 2.2% in November 2020 and stabilized at this level thereafter, which monitors the mortality risk of COVID-19 on a real-time basis. We identified a link between the SARS-CoV-2 mutation activity at molecular scale and COVID-19 mortality risk at population scale, and found that the 501Y variants may slightly but not significantly increase 18% of fatality risk than the preceding 501N variants. We found no statistically significant evidence of change in COVID-19 mortality risk associated with 501Y variants, and highlighted the real-time estimating potentials of the modelling framework.


Assuntos
COVID-19/mortalidade , COVID-19/virologia , Mutação , SARS-CoV-2/genética , Humanos , Funções Verossimilhança , Modelos Biológicos , Pandemias , Saúde Pública , Reino Unido/epidemiologia
11.
Viruses ; 13(4)2021 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-33916601

RESUMO

Assessment of influenza vaccine effectiveness (VE) and identification of relevant influencing factors are the current priorities for optimizing vaccines to reduce the impacts of influenza. To date, how the difference between epidemic strains and vaccine strains at genetic scale affects age-specific vaccine performance remains ambiguous. This study investigated the association between genetic mismatch on hemagglutinin and neuraminidase genes and A(H1N1)pdm09 VE in different age groups with a novel computational approach. We found significant linear relationships between VE and genetic mismatch in children, young adults, and middle-aged adults. In the children's group, each 3-key amino acid mutation was associated with an average of 10% decrease in vaccine effectiveness in a given epidemic season, and genetic mismatch exerted no influence on VE for the elderly group. We demonstrated that present vaccines were most effective for children, while protection for the elderly was reduced and indifferent to vaccine component updates. Modeling such relationships is practical to inform timely evaluation of VE in different groups of populations during mass vaccination and may inform age-specific vaccination regimens.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/genética , Influenza Humana/prevenção & controle , Potência de Vacina , Adolescente , Adulto , Fatores Etários , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Hemaglutininas Virais/genética , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/genética , Vacinas contra Influenza/administração & dosagem , Pessoa de Meia-Idade , Neuraminidase/genética , Estações do Ano , Vacinação/estatística & dados numéricos , Adulto Jovem
12.
Theor Biol Med Model ; 18(1): 10, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750399

RESUMO

BACKGROUND: The COVID-19 pandemic poses a serious threat to global health, and pathogenic mutations are a major challenge to disease control. We developed a statistical framework to explore the association between molecular-level mutation activity of SARS-CoV-2 and population-level disease transmissibility of COVID-19. METHODS: We estimated the instantaneous transmissibility of COVID-19 by using the time-varying reproduction number (Rt). The mutation activity in SARS-CoV-2 is quantified empirically depending on (i) the prevalence of emerged amino acid substitutions and (ii) the frequency of these substitutions in the whole sequence. Using the likelihood-based approach, a statistical framework is developed to examine the association between mutation activity and Rt. We adopted the COVID-19 surveillance data in California as an example for demonstration. RESULTS: We found a significant positive association between population-level COVID-19 transmissibility and the D614G substitution on the SARS-CoV-2 spike protein. We estimate that a per 0.01 increase in the prevalence of glycine (G) on codon 614 is positively associated with a 0.49% (95% CI: 0.39 to 0.59) increase in Rt, which explains 61% of the Rt variation after accounting for the control measures. We remark that the modeling framework can be extended to study other infectious pathogens. CONCLUSIONS: Our findings show a link between the molecular-level mutation activity of SARS-CoV-2 and population-level transmission of COVID-19 to provide further evidence for a positive association between the D614G substitution and Rt. Future studies exploring the mechanism between SARS-CoV-2 mutations and COVID-19 infectivity are warranted.


Assuntos
Substituição de Aminoácidos , COVID-19/transmissão , Glicoproteína da Espícula de Coronavírus/genética , California/epidemiologia , Humanos , Funções Verossimilhança , Pandemias
14.
Int J Infect Dis ; 100: 255-257, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32841687

RESUMO

OBJECTIVES: Characterizing and predicting the evolutionary process of influenza, which remains challenging, are of importance in capturing the patterns of influenza activities and the development of prevention and control strategies. In this study, we quantified genetic mutation activity and developed a statistical model to predict dominant influenza A serotype with limited sequencing data. DATA AND METHODS: A total number of 8097 and 7090 HA sequences for A/H1N1 and A/H3N2 were collected from 2008/09 to 2018/19 flu season in seven countries or regions. And g-measure, which reflected the overall level of genetic activity through time, was considered to predict dominant flu serotype in population. RESULTS: The model discriminated the influenza serotypes well with the sensitivity = 0.84, precision = 0.79 and AUC = 0.78 (95% CI: 0.54 - 0.97), and explained 42% of the serotypes variability with the R2. CONCLUSIONS: Our study suggests that the dominance of flu serotype in population can be well discriminated by genetic mutation activities from sample strains. By the data-driven computational framework, the genetic mutation can be quantified to trace the genetic activities on a real-time basis, and provide early warning for the coming flu season.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/epidemiologia , Modelos Estatísticos , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/virologia , Mutação , Sorogrupo
15.
Infect Drug Resist ; 13: 1851-1861, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606834

RESUMO

BACKGROUND: Measles, a highly contagious disease, still poses a huge burden worldwide. Lately, a trend of resurgence threatened the developed countries. A measles outbreak occurred in the Hong Kong International Airport (HKIA) between March and April 2019, which infected 29 airport staff. During the outbreak, multiple measures were taken including daily situation updates, setting up a public enquiry platform on March 23, and an emergent vaccination program targeting unprotected staff. The outbreak was put out promptly. The effectiveness of these measures was unclear. METHODS: We quantified the transmissibility of outbreak in HKIA by the effective reproduction number, R eff(t), and basic reproduction number, R 0(t). The reproduction number was modelled as a function of its determinants that were statistically examined, including lags in hospitalization, situation update, and level of public awareness. Then, we considered a hypothetical no-measure scenario when improvements in reporting and public enquiry were absent and calculated the number of infected airport staff. RESULTS: Our estimated average R 0 is 10.09 (95% CI: 1.73-36.50). We found that R 0(t) was positively associated with lags in hospitalization and situation update, while negatively associated with the level of public awareness. The average predicted basic reproduction number, r 0, was 14.67 (95% CI: 9.01-45.32) under the no-measure scenario, which increased the average R 0 by 77.57% (95% CI: 1.71-111.15). The total number of infected staff would be 179 (IQR: 90-339, 95% CI: 23-821), namely the measure induced 8.42-fold (95% CI: 0.21-42.21) reduction in the total number of infected staff. CONCLUSION: Timely reporting on outbreak situation and public awareness measured by the number of public enquiries helped to control the outbreak.

16.
Cytokine ; 123: 154765, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31255913

RESUMO

OBJECTIVE: New clinical indicators are urgently needed for predicting the progression and complications of hand-foot-and-mouth disease (HFMD) caused by EV-A71 infections. MATERIALS AND METHODS: Serum specimens from 132 EV-A71 HFMD patients and 73 health children were collected during 2012-2014 in Shenzhen, China. The specific cytokines/chemokines were detected with a 274-human cytokine antibody array, followed by a 38-inflammation cytokine array, and further validated by ELISA. RESULTS: Cytokines varied in different severity of EV-A71 HFMD patients. The ROC curve analysis revealed 5 serum cytokines with high sensitivity and specificity in predicting the disease progression. Eotaxin, IL-8 and IP-10 have showed high AUC values (0.90-0.95) for discrimination between the health controls and the patient group. The three cytokines showed high sensitivity (80-91%) and specificity (88-95%). MMP-8 had a high sensitivity and specificity to predict mild HFMD (100%, 100%). IL-1b and leptin discriminated the severe/critical group from the mild group (79% and 69% in sensitivity, 73% and 63% in specificity). CONCLUSIONS: Eotaxin, IP-10 and IL-8 could be potential indicators for predicting HFMD progression with EV-A71 infection. MMP-8 is a specific indicator for mild infection, while IL-1b and leptin display potential for predicting the severity and criticality.


Assuntos
Quimiocinas/sangue , Enterovirus Humano A/metabolismo , Doença de Mão, Pé e Boca/sangue , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Análise Serial de Proteínas
17.
Radiother Oncol ; 138: 93-98, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31252300

RESUMO

BACKGROUND AND PURPOSE: Radiation-induced hypoglossal nerve palsy is a debilitating and irreversible late complication after definitive radiotherapy for nasopharyngeal carcinoma (NPC) and other skull base tumors. This study sets to evaluate its incidence and clinical predictive factors, and to propose relevant dosimetric constraints for this structure to guide radiotherapy planning. MATERIALS AND METHODS: We undertook a retrospective review of 797 NPC patients who underwent definitive intensity-modulated radiotherapy (IMRT) between 2003 and 2011. Cumulative incidence and clinical predictors for radiation-induced hypoglossal nerve palsy were evaluated. Archived radiotherapy plans were retrieved and 330 independent hypoglossal nerves were retrospectively contoured following standardized atlas. Optimal threshold analyses of dosimetric parameters (Dmax, D0.5cc, D1cc, D2cc, Dmean) were conducted using receiver operating characteristic curves. Normal tissue complication probability was generated with logistic regression modeling. RESULTS: With a median follow-up of 8.1 years, sixty-nine (8.7%) patients developed radiation-induced hypoglossal nerve palsy. High radiotherapy dose, premorbid diabetes, advanced T-stage and radiological hypoglossal canal involvement were independent clinical risk factors. Maximum dose received by 1 cc volume (D1cc) was the best predictor for the development of radiation-induced nerve palsy (AUC = 0.826) at 8 years after IMRT. Hypoglossal nerves with D1cc of 74 Gy EQD2 had an estimated palsy risk of 4.7%. Nerves with D1cc <74 Gy EQD2 had significantly lower risk of palsy than those ≥74 Gy EQD2 (2.4% vs 20.8%, p <0.001). CONCLUSION: Incidence of radiation-induced hypoglossal nerve palsy was high after definitive IMRT for NPC. D1cc <74 Gy EQD2 can serve as a useful dose constraint to adopt during radiotherapy planning to limit palsy risk to <5% at 8 years after IMRT.


Assuntos
Doenças do Nervo Hipoglosso/etiologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/etiologia , Estudos de Coortes , Feminino , Humanos , Doenças do Nervo Hipoglosso/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Lesões por Radiação/epidemiologia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/estatística & dados numéricos , Estudos Retrospectivos
18.
Eur Radiol ; 29(10): 5627-5634, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30903340

RESUMO

OBJECTIVES: MRI can detect early-stage nasopharyngeal carcinoma (NPC), but the detection is more challenging in early-stage NPCs because they must be distinguished from benign hyperplasia in the nasopharynx. This study aimed to determine whether intravoxel incoherent motion diffusion-weighted imaging (IVIM DWI) MRI could distinguish between these two entities. METHODS: Thirty-four subjects with early-stage NPC and 30 subjects with benign hyperplasia prospectively underwent IVIM DWI. The mean pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f) and apparent diffusion coefficient (ADC) values were calculated for all subjects and compared between the 2 groups using Student's t test. Receiver operating characteristics with the area under the curve (AUC) was used to identify the optimal threshold for all significant parameters, and the corresponding diagnostic performance was calculated. A p value of < 0.05 was considered statistically significant. RESULTS: Compared with benign hyperplasia, early-stage NPC exhibited a significantly lower D mean (0.64 ± 0.06 vs 0.87 ± 0.11 × 10-3 mm2/s), ADC0-1000 mean (0.77 ± 0.08 vs 1.00 ± 0.13 × 10-3 mm2/s), ADC300-1000 (0.63 ± 0.05 vs 0.86 ± 0.10 × 10-3 mm2/s) and a higher D* mean (32.66 ± 4.79 vs 21.96 ± 5.21 × 10-3 mm2/s) (all p < 0.001). No significant difference in the f mean was observed between the two groups (p = 0.216). The D and ADC300-1000 mean had the highest AUC of 0.985 and 0.988, respectively, and the D mean of < 0.75 × 10-3 mm2/s yielded the highest sensitivity, specificity and accuracy (100%, 93.3% and 96.9%, respectively) in distinguishing early-stage NPC from benign hyperplasia. CONCLUSION: DWI has potential to distinguish early-stage NPC from benign hyperplasia and D and ADC300-1000 mean were the most promising parameters. KEY POINTS: • Diffusion-weighted imaging has potential to distinguish early-stage nasopharyngeal carcinoma from benign hyperplasia in the nasopharynx. • The pure diffusion coefficient, pseudo-diffusion coefficient from intravoxel incoherent motion model and apparent diffusion coefficient from conventional diffusion-weighted imaging were significant parameters for distinguishing these two entities in the nasopharynx. • The pure diffusion coefficient, followed by apparent diffusion coefficient, may be the most promising parameters to be used in screening studies to help detect early-stage nasopharyngeal carcinoma.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Detecção Precoce de Câncer/métodos , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia/diagnóstico , Masculino , Pessoa de Meia-Idade , Doenças Nasofaríngeas/diagnóstico , Curva ROC , Reprodutibilidade dos Testes
19.
BMC Endocr Disord ; 18(1): 59, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30170579

RESUMO

BACKGROUND: Galactomannan(s) are plant-derived fiber shown to reduce post-prandial blood glucose by delaying intestinal absorption of carbohydrates and slowing down gastric emptying. We examined glucose-lowering effects of BTI320, a propriety fractionated mannan(s) administered as a chewable tablet before meal in a proof-of-concept study in Chinese subjects with prediabetes. METHODS: Sixty Chinese adults aged 18-70 years with either impaired fasting glucose, impaired glucose tolerance, or glycated haemoglobin 5.7-6.4% (39-46 mmol/mol), were randomly assigned in 2:2:1 ratio to either BTI320 8 g (high dose), BTI320 4 g (low dose) or matching-placebo three times daily before meal for 16 weeks. The primary endpoint was change in fructosamine in subjects treated with BTI320 compared with placebo from baseline to week 4. Indices of glycaemic variability based on continuous glucose monitoring (CGM) and standard meal tolerance test were explored in secondary analyses. RESULTS: Of 60 subjects randomized, 3 subjects discontinued study treatment prematurely. In intention-to-treat analysis, no significant differences in change in serum fructosamine between low or high dose BTI320 and placebo were observed. Using random effect models, adjusted for variability by meals, treatment with low dose BTI320 was associated with reduction in 1-h (p < 0.01), 2-h (p = 0.01) and 3-h (p = 0.02) post-prandial incremental glucose area-under-curve and post-meal maximum glucose (p = 0.03) compared with placebo. Subjects receiving low dose BTI320 had greater body weight reduction than placebo group. CONCLUSIONS: BTI320 did not change fructosamine levels compared with placebo. BTI320 reduced glycaemic variability based on CGM indices. TRIAL REGISTRATION: The study was registered at www.clinicaltrials.gov , reference number NCT02358668 (9 February 2015).


Assuntos
Galactanos/uso terapêutico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Mananas/uso terapêutico , Gomas Vegetais/uso terapêutico , Período Pós-Prandial/efeitos dos fármacos , Estado Pré-Diabético/tratamento farmacológico , Estudo de Prova de Conceito , Idoso , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , China/epidemiologia , Método Duplo-Cego , Feminino , Galactanos/efeitos adversos , Hong Kong/epidemiologia , Humanos , Hiperglicemia/sangue , Hiperglicemia/epidemiologia , Hipoglicemiantes/efeitos adversos , Masculino , Mananas/efeitos adversos , Pessoa de Meia-Idade , Gomas Vegetais/efeitos adversos , Período Pós-Prandial/fisiologia , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Resultado do Tratamento
20.
J Clin Oncol ; : JCO2018777847, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29989858

RESUMO

Purpose The contribution of adjuvant chemotherapy after chemoradiation therapy (CRT) in nasopharyngeal cancer (NPC) remains controversial. Plasma Epstein-Barr virus (EBV) DNA is a potential biomarker of subclinical residual disease in NPC. In this prospective, multicenter, randomized controlled trial, we used plasma EBV DNA to identify patients with NPC at a higher risk of relapse for adjuvant chemotherapy. Patients and Methods Eligible patients with histologically confirmed NPC of Union for International Cancer Control stage IIB to IVB, adequate organ function, and no locoregional disease or distant metastasis were screened by plasma EBV DNA at 6 to 8 weeks after radiotherapy (RT). Patients with undetectable plasma EBV DNA underwent standard surveillance. Patients with detectable plasma EBV DNA were randomly assigned to either adjuvant chemotherapy with cisplatin and gemcitabine for six cycles (arm 1) or observation (arm 2). Patients were stratified for primary treatment (RT v CRT) and stage (II/III v IV). The primary end point was relapse-free survival (RFS). Results Seven hundred eighty-nine patients underwent EBV DNA screening. Plasma EBV DNA was undetectable in 573 (72.6%) and detectable in 216 (27.4%); 104 (13.2%) with detectable EBV DNA were randomly assigned to arms 1 (n = 52) and 2 (n = 52). After a median follow-up of 6.6 years, no significant difference was found in 5-year RFS rate between arms 1 and 2 (49.3% v 54.7%; P = .75; hazard ratio for relapse or death, 1.09; 95% CI, 0.63 to 1.89). The level of post-RT plasma EBV DNA correlated significantly with the hazards of locoregional failure, distant metastasis, and death. Conclusion In patients with NPC with detectable post-RT plasma EBV DNA, adjuvant chemotherapy with cisplatin and gemcitabine did not improve RFS. Post-RT plasma EBV DNA level should be incorporated as the selection factor in future clinical trials of adjuvant therapy in NPC.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA