RESUMO
BACKGROUND: Lip, oral cavity, and oropharyngeal squamous cell carcinoma (SCC) represent a major health problem in the global scenario. In South America, the highest incidence rates are seen in Brazil. Therefore, the epidemiological and clinical profile and survival outcomes of lip, oral cavity, and oropharyngeal SCC was studied in São Paulo State, Brazil. MATERIAL AND METHODS: The clinicopathological data of 12,099 patients with lip, oral cavity, and oropharyngeal SCC were obtained from hospital cancer registries of the Fundação Oncocentro de São Paulo, Brazil (2010-2015). Survival rates and other analyses were performed using SPSS software. RESULTS: A clear male predominance was observed, particularly for patients with oropharyngeal SCC (88.3%). The average age of patients was higher for lip cases (65 ± 13.5 years) compared to other sites. The schooling level was low for most patients, especially in lip cases (87.9%). Most of the patients with oral cavity (71.8%) and oropharyngeal (86.3%) SCC had advanced-stage (III-IV) disease. However, the majority of lip cases (83.3%) were at an early stage (I-II). Surgical excision was the main treatment for lip (72%) and oral cavity SCC (23.5%), and chemoradiotherapy was the main treatment for oropharyngeal SCC (40.2%). The 5-year overall survival (OS) for patients with lip, oral cavity, and oropharyngeal SCC were 66.3, 30.9, and 22.6%, respectively. Multivariate analysis revealed that the determinants of OS were different for lip, oral cavity, and oropharyngeal SCC, except for those at the clinical stage, which was an independent predictor for all sites. CONCLUSIONS: OS-independent determinants varied according to the affected site. Oral cavity and oropharyngeal SCC presented worse survival rates than those for lip SCC.
Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Neoplasias Orofaríngeas , Idoso , Brasil/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/terapia , Feminino , Humanos , Lábio/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/terapia , Neoplasias Orofaríngeas/epidemiologia , Neoplasias Orofaríngeas/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapiaAssuntos
Neoplasias do Ânus/diagnóstico , COVID-19 , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/tendências , Acessibilidade aos Serviços de Saúde/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Ânus/economia , Neoplasias do Ânus/epidemiologia , Neoplasias do Ânus/patologia , Brasil/epidemiologia , Neoplasias Colorretais/economia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Estudos Transversais , Detecção Precoce de Câncer/economia , Feminino , Acessibilidade aos Serviços de Saúde/economia , Humanos , Masculino , Pessoas sem Cobertura de Seguro de Saúde/estatística & dados numéricos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Encaminhamento e Consulta/economia , Encaminhamento e Consulta/tendênciasRESUMO
We investigated the association between an aggrecan gene (ACAN) polymorphism and lumbar disc herniation (LDH). This was a case-control study with quinquennial age and gender groups. The study comprised 119 men and women aged between 20 and 60 from Goiânia (Brazil). Of these, 39 were allocated to the case group (Ca) and 80 to the control group (Ct). We gathered sociodemographic and clinical data, and peripheral blood samples. DNA was isolated for genotyping the ACAN variable number tandem repeat (VNTR) via conventional polymerase chain reaction (PCR). Data were statistically analyzed using the chi-square test, multiple comparison analysis, the Student t-test, and odds ratios, with a level of significance set at 5% (P ≤ 0.05). The groups were homogenous in terms of sociodemographic, anthropometric, and life style variables. The allele score for the ACAN VNTR was significantly lower in volunteers with LDH; the A22 allele was significantly more prevalent in this same group; the Ca group presented greater frequency of short alleles A13-A25, whereas the Ct group presented a higher frequency of long alleles. However, this difference was not statistically significant. In both groups, the most common alleles were A28, A27, and A29, and the A26/A26 genotype was significantly more common in the Ca group. The results showed an association between short alleles and LDH among the investigated adults (Ca), corroborating the hypothesis that aggrecan with shorter repeat lengths can lead to a reduction in the physiological proteoglycan function of intervertebral disc hydration and, consequently, increased individual susceptibility to LDH.
Assuntos
Agrecanas/genética , Degeneração do Disco Intervertebral/genética , Deslocamento do Disco Intervertebral/genética , Repetições Minissatélites , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
PURPOSE: The aim of this study is to analyze mortality trends of HPV-related cancers in Spain by gender, during the period 1996-2010, and make predictions until the year 2025. METHODS: All deaths registered as cervical cancer were registered (ICD-10 code: C53), as well as vulvar and vaginal (C51 and C52), anal (C21), penile (C60), and oropharyngeal (C02, C09, C10). Adjusted rate calculations for each year were used to study the trends through the regression program Joinpoint. Predictions were made using the Nordpred program, utilizing the age-period-cohort model. RESULTS: In men, a statistically significant increase was observed in mortality by anal cancer, a reduction was observed in oropharyngeal cancer mortality and penile cancer rates were stable. In women, a statistically significant decreasing trend was observed for cervical, vulvar and vaginal cancers. In the predictions, the annual change relative to risk or population changes (size and structure) revealed a reduction in death risk by oropharyngeal cancer in men, and a reduction in death risk by anal cancer in women, although stable adjusted rates were verified for anal cancer in women. CONCLUSIONS: Although an increase was identified in the number of deaths for both genders, rates indicate gender differences in the trends, with increased rates for anal cancer and reduced rates for oropharyngeal cancer in men. Women presented reduced rates for cervical, vulvar, and vaginal cancers. For penile cancer and anal cancer in women, stable trends were verified.
Assuntos
Neoplasias/mortalidade , Neoplasias/virologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Feminino , Previsões , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Sistema de Registros , Espanha/epidemiologia , Adulto JovemRESUMO
The association of education, tobacco smoking, alcohol consumption, and interleukin-2 (IL-2 +114 and -384) and -6 (IL-6 -174) DNA polymorphisms with head and neck squamous cell carcinoma (HNSCC) was investigated in a cohort study of 445 subjects. IL-2 and IL-6 genotypes were determined by real-time PCR. Cox regression was used to estimate hazard ratios (HR) and 95 percent confidence intervals (95 percentCI) of disease-specific survival according to anatomical sites of the head and neck. Mean age was 56 years and most patients were males (87.6 percent). Subjects with 5 or more years of schooling had better survival in larynx cancer. Smoking had no effect on HNSCC survival, but alcohol consumption had a statistically significant effect on larynx cancer. IL-2 gene +114 G/T (HR = 0.52; 95 percentCI = 0.15-1.81) and T/T (HR = 0.22; 95 percentCI = 0.02-3.19) genotypes were associated with better survival in hypopharynx cancer. IL-2 +114 G/T was a predictor of poor survival in oral cavity/oropharynx cancer and larynx cancer (HR = 1.32; 95 percentCI = 0.61-2.85). IL-2 -384 G/T was associated with better survival in oral cavity/oropharynx cancer (HR = 0.80; 95 percentCI = 0.45-1.42) and hypopharynx cancer (HR = 0.68; 95 percentCI = 0.21-2.20), but an inverse relationship was observed for larynx cancer. IL-6 -174 G/C was associated with better survival in hypopharynx cancer (HR = 0.68; 95 percentCI = 0.26-1.78) and larynx cancer (HR = 0.93; 95 percentCI = 0.42-2.07), and C/C reduced mortality in larynx cancer. In general, our results are similar to previous reports on the value of education, smoking, alcohol consumption, and IL-2 and IL-6 genetic polymorphisms for the prognosis of HNSCC, but the risks due to these variables are small and estimates imprecise.
Assuntos
Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas/mortalidade , Neoplasias de Cabeça e Pescoço/mortalidade , /genética , /genética , Polimorfismo Genético/genética , Consumo de Bebidas Alcoólicas/efeitos adversos , Estudos de Coortes , Carcinoma de Células Escamosas/etiologia , Intervalo Livre de Doença , Escolaridade , Genótipo , Neoplasias de Cabeça e Pescoço/etiologia , Prognóstico , Fatores de Risco , Fumar/efeitos adversosRESUMO
The association of education, tobacco smoking, alcohol consumption, and interleukin-2 (IL-2 +114 and -384) and -6 (IL-6 -174) DNA polymorphisms with head and neck squamous cell carcinoma (HNSCC) was investigated in a cohort study of 445 subjects. IL-2 and IL-6 genotypes were determined by real-time PCR. Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) of disease-specific survival according to anatomical sites of the head and neck. Mean age was 56 years and most patients were males (87.6%). Subjects with 5 or more years of schooling had better survival in larynx cancer. Smoking had no effect on HNSCC survival, but alcohol consumption had a statistically significant effect on larynx cancer. IL-2 gene +114 G/T (HR = 0.52; 95%CI = 0.15-1.81) and T/T (HR = 0.22; 95%CI = 0.02-3.19) genotypes were associated with better survival in hypopharynx cancer. IL-2 +114 G/T was a predictor of poor survival in oral cavity/oropharynx cancer and larynx cancer (HR = 1.32; 95%CI = 0.61-2.85). IL-2 -384 G/T was associated with better survival in oral cavity/oropharynx cancer (HR = 0.80; 95%CI = 0.45-1.42) and hypopharynx cancer (HR = 0.68; 95%CI = 0.21-2.20), but an inverse relationship was observed for larynx cancer. IL-6 -174 G/C was associated with better survival in hypopharynx cancer (HR = 0.68; 95%CI = 0.26-1.78) and larynx cancer (HR = 0.93; 95%CI = 0.42-2.07), and C/C reduced mortality in larynx cancer. In general, our results are similar to previous reports on the value of education, smoking, alcohol consumption, and IL-2 and IL-6 genetic polymorphisms for the prognosis of HNSCC, but the risks due to these variables are small and estimates imprecise.
Assuntos
Carcinoma de Células Escamosas/mortalidade , Neoplasias de Cabeça e Pescoço/mortalidade , Interleucina-2/genética , Interleucina-6/genética , Polimorfismo Genético/genética , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinoma de Células Escamosas/etiologia , Estudos de Coortes , Intervalo Livre de Doença , Escolaridade , Feminino , Genótipo , Neoplasias de Cabeça e Pescoço/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Fumar/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
Specific genotypes appear to be related to the development of thyroid disease. We examined whether polymorphisms of the genes CYP1A1, GSTM1, GSTT1, and TP53 at codon 72 are associated with increased risk for thyroid nodules. Blood samples were obtained from 122 thyroid patients with nodules and from 134 healthy control individuals from Goiânia city, GO, Brazil. We found no significant association of CYP1A1m1 and CYP1A1m2 genotypes with thyroid diseases (P > 0.05). The null genotypes of GSTM1 and GSTT1 genes were predominant in patients with nodules, indicating that individuals that possess these genotypes have a predisposition for thyroid disease. The genotype p53Arg Arg was associated with a low risk for thyroid cancer (OR = 0.15; P < 0.0001), indicating that the arginine allele in homozygosis could have a protective effect against carcinogenesis. On the other hand, the p53ArgPro genotype was significantly associated with malignant neoplastic nodules (OR = 3.65; P = 0.001). Interindividual variation in susceptibility to thyroid diseases could provide new perspectives for early diagnosis, prognosis and treatment, indicating which patients with thyroid nodules will benefit from treatment, depending on specific polymorphic profiles.
Assuntos
Citocromo P-450 CYP1A1/genética , Glutationa Transferase/genética , Polimorfismo Genético , Nódulo da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Estudos de Casos e Controles , Primers do DNA , Genótipo , Humanos , Pessoa de Meia-Idade , Adulto JovemRESUMO
Cancers of the upper aerodigestive tract [(UADT): oral cavity, pharynx, larynx and oesophagus] have high incidence rates in some parts of South America. Alterations in the TP53 gene are common in these cancers. In our study, we have estimated the prevalence and patterns of TP53 mutations (exons 4-10) in 236 UADT tumours from South America in relation to lifestyle risk factors, such as tobacco smoking and alcohol drinking. Moreover, we have conducted a pilot study of EGFR mutations (exons 18-21) in 45 tumours from the same population. TP53 mutation prevalence was high: 59% of tumours were found to carry mutant TP53. We found an association between TP53 mutations and tobacco smoking and alcohol drinking. The mutation rate increased from 38% in never-smokers to 66% in current smokers (P-value for trend = 0.09). G:C>T:A transversions were found only in smokers (15%). Alcohol drinkers carried more G:C>A:T transitions (P = 0.08). Non-exposed individuals were more probable to carry G:C>A:T transitions at CpG sites (P = 0.01 for never-smokers and P < 0.001 for never-drinkers). EGFR mutations were found in 4% of cases. Inactivation of TP53 by mutations is a crucial molecular event in the UADT carcinogenesis and it is closely related to exposure to lifestyle risk factors. EGFR mutations do not appear to be a common event in UADT carcinogenesis in this population.
Assuntos
Receptores ErbB/genética , Neoplasias Esofágicas/epidemiologia , Genes p53 , Neoplasias de Cabeça e Pescoço/epidemiologia , Estilo de Vida , Adulto , Idoso , Estudos de Casos e Controles , Cocarcinogênese , Neoplasias Esofágicas/genética , Feminino , Neoplasias de Cabeça e Pescoço/genética , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Risco , América do Sul/epidemiologiaRESUMO
A interação do genoma do HPV com o genoma da célula hospedeira ou de proteínas virais com proteínas celulares necessárias ao controle do ciclo celular desencadeia a morte celular ou age como fator de iniciação e progressão de processos malignos. Diversostrabalhos têm sido desenvolvidos no sentido de associar a infecção de HPV aos cânceres de cabeça e pescoço. O objetivo do presente estudo foi comparar a detecção do genoma de HPV em pacientes com CEC da laringe, considerando os ensaios de PCR convencional e em tempo real. O grupo amostral foi constituído de 15 pacientes do Registro de Câncer de Base Populacional da ACCG. Das peças cirúrgicas, foi obtido DNA total, usado na investigação molecular, para detecção do genoma de HPV, utilizando os primers genéricos GP05/06, que detectam todos os tipos de HPV. O genoma de HPV foi amplificado em 30 dos casos por PCR convencional e no ensaio de PCR em tempo real apresentaram amplificação em 46,7 das amostras, evidenciando uma diferença em 40 . Os estudosde associação entre o HPV e os cânceres da laringe são importantes no sentido de ampliar o conhecimento acerca dos mecanismos de infecção, iniciação e promoção tumoral potencializada por estes vírus.
Assuntos
Humanos , Carcinoma de Células Escamosas , Estudo Comparativo , Genes Supressores de Tumor , Neoplasias Laríngeas , Laringe , Técnicas de Diagnóstico Molecular , Infecções por Papillomavirus , Reação em Cadeia da PolimeraseRESUMO
Este estudo propõe-se a uma breve revisão da literatura sobre qualidade de vida (QV) e câncer de cabeça e pescoço, bem como avaliar a reação de enfermos com esta patologia frente a Escala de Qualidade de Vida desenvolvida por Font - 1988 (Costa Neto, 1997). Participaram do estudo 43 pacientes do Serviço de Cirurgia de Cabeça e Pescoço do Hospital Araújo Jorge - ACCG, que foram abordados individualmente na ocasião da consulta médica ou durante a internação hospitalar. Houve o predomínio de casos masculinos (55,8 por cento) sobre os femininos (44,2 por cento), a maioria em tratamento cirúrgico exclusivo (60 por cento), com idade entre 51 e 60 anos (28 por cento), com nenhuma (21 por cento) ou pouca escolarização (36 por cento). Cerca de 44 por cento nao trabalhava devido ao câncer. As neoplasias mais freqüentes eram da boca (25 por cento), e tireóide (19 por cento) e laringe (16 por cento). Na subescala (S-E) Sintomas, predominaram os fatores dor (38 por cento) e naúseas (23 por cento). Na S-E Dificuldades nos Hábitos Cotidianos, as atividades laborais (62 por cento). Na S-E Dificuldades Sociais/Familiares, preocupação com os filhos (60 por cento) e preocupações econômicas (58 por cento). Na S-E Fatores Psicológicos, Insatisfação com o Próprio Corpo (54 por cento) e Medo (49 por cento). No geral, houve uma perda média de 35 por cento na QV dos enfermos. Conclui-se que a Escala de QV de Font é apropriada para sujeitos com câncer de cabeça e pescoço, mas sugere-se associá-la a entrevistas semi-estruturadas, uma vez que as dimensões de significado não são avaliadas por instrumentos mais objetivos.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Condições Sociais , Neoplasias de Cabeça e Pescoço/psicologia , Neoplasias de Cabeça e Pescoço/terapia , Qualidade de VidaRESUMO
The authors investigated the joint effects of tobacco and alcohol consumption on the risk of squamous cell carcinomas of the upper aero-digestive tract (UADT) using data from a hospital-based case-control study conducted in southern Brazil, 1986-1989. A total of 784 cases of cancers of the mouth, pharynx, and larynx and 1,578 non-cancer controls matched on age, sex, hospital catchment area, and period of admission were interviewed about their smoking and drinking habits and other characteristics. Using logistic regression, evidence was found for interaction between the cumulative exposures for smoking and alcohol on UADT cancer risk. The joint effects for pharyngeal cancers exceeded the levels expected under a multiplicative model for moderate smokers (p = 0.007). There was little statistical evidence, however, for interaction on cancers of the mouth (p = 0.28) or larynx (p = 0.95). Among never smokers, heavy drinkers had 9.2 times (95% confidence interval 1.7, 48.5) greater risk of cancers of mouth, pharynx, and supraglottis than never drinkers, with a dose-response trend (p = 0.013) with cumulative consumption. The authors conclude that the interaction occurring in the pharynx between smoking and alcohol on UADT cancers is not uniform, with varying effects depending on the level of smoking exposure. Alcohol may act as both a promoter for tobacco and as an independent risk factor.
Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias Laríngeas/epidemiologia , Neoplasias Bucais/epidemiologia , Neoplasias Faríngeas/epidemiologia , Fumar/efeitos adversos , Brasil/epidemiologia , Estudos de Casos e Controles , Intervalos de Confiança , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de RiscoRESUMO
We examined the relationship between dental health variables and risk of upper aerodigestive tract (UADT) cancers in a case-control study in Southern Brazil. The study population included 717 cases of cancers of the mouth, pharynx, and larynx and 1434 controls matched on age, gender, period of admission and study site. The association with dental factors was investigated by conditional logistic regression using extensive adjustment for a priori and empirical confounders, including tobacco and alcohol consumption, diet and sociodemographic variables. Lifetime use of dentures was not associated with risk of any UADT cancer, but history of oral sores secondary to ill-fitting dentures was associated with cancers of the mouth (odds ratio [OR] = 2.3, 95% confidence interval [CI] 1.2-4.6) and of the pharynx (OR = 2.7, 95% CI 1.1-6.2) among those using dentures. The association for mouth cancers was restricted primarily to an increased risk of tongue neoplasms (OR = 9.1, 95% CI 1.9-43.4). Less than daily tooth brushing frequency was also associated with risk of cancer of the tongue (OR = 2.1, 95% CI 1.0-4.3) and of other parts of the mouth (OR = 2.4, 95% CI 1.0-5.4). Having broken teeth was not significantly associated with risk of UADT cancer of any site. We conclude that poor oral hygiene due to infrequent tooth brushing and sores caused by dentures are risk factors for cancer of the mouth and that these associations are unlikely to be due to insufficient control of confounding.
Assuntos
Carcinoma de Células Escamosas/etiologia , Neoplasias Laríngeas/etiologia , Neoplasias Bucais/etiologia , Higiene Bucal , Neoplasias Faríngeas/etiologia , Adulto , Idoso , Brasil/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , Inquéritos de Saúde Bucal , Dentaduras , Feminino , Humanos , Neoplasias Laríngeas/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Faríngeas/epidemiologia , Fatores de Risco , Escovação DentáriaRESUMO
The radiation accident in focus here occurred in a section of Goiânia (Brazil) where more than a hundred individuals were contaminated with 137Cesium on September 1987. In order to estimate the absorbed radiation doses, initial frequencies of dicentrics and rings were determined in 129 victims [A.T. Ramalho, PhD Thesis, Subsidios a tecnica de dosimetria citogenetica gerados a partir da analise de resultados obtidos com o acidente radiologico de Goiânia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, 1992]. We have followed some of these victims cytogenetically over the years seeking for parameters that could be used as basis for retrospective radiation dosimetry. Our data on translocation frequencies obtained by fluorescence in situ hybridization (FISH) could be directly compared to the baseline frequencies of dicentrics available for those same victims. Our results provided valuable information on how precise these estimates are. The frequencies of translocations observed years after the radiation exposure were two to three times lower than the initial dicentrics frequencies, the differences being larger at higher doses (>1 Gy). The accuracy of such dose estimates might be increased by scoring sufficient amount of cells. However, factors such as the persistence of translocation carrying lymphocytes, translocation levels not proportional to chromosome size, and inter-individual variation reduce the precision of these estimates.
Assuntos
Radioisótopos de Césio/efeitos adversos , Aberrações Cromossômicas/genética , Hibridização in Situ Fluorescente , Liberação Nociva de Radioativos , Brasil , Células Cultivadas , Feminino , Seguimentos , Raios gama/efeitos adversos , Humanos , Linfócitos/efeitos da radiação , Masculino , Radiometria , Estudos Retrospectivos , Translocação Genética/efeitos da radiaçãoRESUMO
We examined the relationship between dental health variables and risk of upper aerodigestive tract (UADT) cancers in a case-control study in Southern Brazil. The study population included 717 cases of cancers of the mouth, pharynx, and larynx and 1434 controls matched on age, gender, period of admission and study site. The association with dental factors was investigated by conditional logistic regression using extensive adjustment for a priori and empirical confounders, including tobacco and alcohol consumption, diet and sociodemographic variables. Lifetime use of dentures was not associated with risk of any UADT cancer, but history of oral sores secondary to ill-fitting dentures was associated with cancers of the mouth (odds ratio [OR] = 2.3, 95 per cent confidence interval [CI] 1.2-4.6) and of the pharynx (OR = 2.7, 95 per cent CI 1.1-6.2) among those using dentures...
Assuntos
Neoplasias Bucais/diagnóstico , Neoplasias Bucais/etiologia , Prótese Dentária/efeitos adversos , Sistema Estomatognático/fisiopatologia , Sistema Estomatognático/lesões , Alcoolismo/complicações , Brasil/epidemiologia , Doenças da Boca , Higiene Bucal/efeitos adversos , Próteses e Implantes , Prótese Dentária/efeitos adversos , Fatores de Risco , Nicotiana/efeitos adversos , Doenças DentáriasRESUMO
BACKGROUND: Incidence rates for cancers of the upper aero-digestive tract in Southern Brazil are among the highest in the world. A case-control study was designed to identify the main risk factors for carcinomas of mouth, pharynx, and larynx in the region. We tested the hypothesis of whether use of wood stoves is associated with these cancers. METHODS: Information on known and potential risk factors was obtained from interviews with 784 cases and 1568 non-cancer controls. We estimated the effect of use of wood stove by conditional logistic regression, with adjustment for smoking, alcohol consumption and for other sociodemographic and dietary variables chosen as empirical confounders based on a change-in-estimate criterion. RESULTS: After extensive adjustment for all the empirical confounders the odds ratio (OR) for all upper aero-digestive tract cancers was 2.68 (95% confidence interval [CI] : 2.2-3.3). Increased risks were also seen in site-specific analyses for mouth (OR = 2.73; 95% CI: 1.8-4.2), pharyngeal (OR = 3.82; 95% CI: 2.0-7.4), and laryngeal carcinomas (OR = 2.34; 95% CI: 1.2-4.7). Significant risk elevations remained for each of the three anatomic sites and for all sites combined even after we purposefully biased the analyses towards the null hypothesis by adjusting the effect of wood stove use only for positive empirical confounders. CONCLUSIONS: The association of use of wood stoves with cancers of the upper aero-digestive tract is genuine and unlikely to result from insufficient control of confounding. Due to its high prevalence, use of wood stoves may be linked to as many as 30% of all cancers occurring in the region.
Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Neoplasias Bucais/etiologia , Neoplasias Otorrinolaringológicas/etiologia , Fumaça/efeitos adversos , Madeira , Idoso , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Razão de Chances , Neoplasias Otorrinolaringológicas/epidemiologia , Estudos Retrospectivos , Fatores de Risco , População UrbanaRESUMO
We have characterized 54 HPRT- point mutations in T-lymphocytes from 17 individuals exposed to ionizing radiation of 137Cs in Goiania, Brazil and compared this spectrum to that of 30 HPRT- mutants from 9 unexposed Brazilian controls. The average internal exposure of the exposed group was 205 mCi, and the average external exposure was 1.7 Gy. The average HPRT- mutant frequency for the exposed group was 13.3 x 10(-5), approximately a 10-fold increase over the mutant frequency of the unexposed controls, which was 1.56 x 10(-5). The types of point mutations characterized included base substitutions, small deletions, frameshifts, insertions, complex mutations, and losses of exon sequences from the mRNA. The relative frequency of the different mutation types was similar in the two studied groups. However, in our study the distribution of events within the hprt coding sequence seemed to cluster at the same regions of the gene. These observations imply that the hprt gene does not present a homogeneous target to radiation mutagenesis, and perhaps this class of information may be used to detect radiation exposure in human populations.
Assuntos
Hipoxantina Fosforribosiltransferase/genética , Mutação Puntual/efeitos da radiação , Linfócitos T/efeitos da radiação , Adolescente , Adulto , Brasil , Criança , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Modern technologies have provided the opportunity to monitor mutations in people in vivo. The subjects of this study were accidentally exposed to 137Cesium in a radiological accident that occurred in September 1987 in Goiânia, Brazil, during which more than 150 people received doses greater than 0.1 Gy and as high as 7 Gy. The objective of this study was to determine how long the hprt mutant T-cells in the peripheral blood contribute to mutant frequency by examining the time-course of the T-lymphocyte response to ionizing radiation. This report describes the results obtained over a period of 2.3 to 4.5 years subsequent to the accident, from 11 subjects with doses ranging from 1 to 7 Gy, and from nine control subjects selected from the same population. The mean In MF (+/- SE) of the control group was 2.5 (+/- 0.2) + In10(-6). The exposed group had a significantly increased mutant frequency; the mean In MF (+/- SE) were 3.3 (+/- 0.3) + In10(-6), 2.8 (+/- 0.2) + In10(-6), and 2.3 (+/- 0.2) + In10(-6), in the years 1990-1992 respectively. Based on the decline of mutant frequency and using Buckton's models [Buckton et al. (1967): Nature 214:470-473], we demonstrated that mutant T-cells have a short-term memory with a half-life of 2.1 years. This relatively short half-life limits the effective use of the hprt assay as the method of choice to monitor past exposure. The data also demonstrate a positive correlation with age, and an inverse correlation with plating efficiency.
Assuntos
Radioisótopos de Césio/efeitos adversos , Raios gama/efeitos adversos , Genes/efeitos da radiação , Hipoxantina Fosforribosiltransferase/genética , Mutagênese , Liberação Nociva de Radioativos , Linfócitos T/enzimologia , Adolescente , Adulto , Fatores Etários , Brasil , Células Clonais , Exposição Ambiental , Feminino , Seguimentos , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Radioterapia/instrumentaçãoRESUMO
Following the radiological accident which occurred in the city of Goiania (Brazil), in September 1987, a cytogenetic follow-up of 15 exposed patients was started, aiming to observe the mean lifetime of lymphocytes containing dicentric and ring aberrations. The results suggest that the disappearance rate of unstable aberrations follows a two-term exponential function. Up to 470 days after exposure, there is a rapid fall in the aberration frequency. After 470 days, the disappearance rate is very slow. These results may reflect different subpopulations of human lymphocytes, with different lifespans. The estimated average half-time of elimination of dicentrics and rings among the highly exposed group (doses above 1 Gy) was 110 days for the initial period after the exposure (up to 470 days). This value is significantly shorter than the usually accepted value of 3 years reported in the literature. Statistical analysis of possible correlations between the individual half-times and biological parameters, such as sex, age, leukopenia level shown during the critical period, absorbed dose (initial frequency of chromosomal aberrations) and the administration of the bone marrow stimulating factor (rHuGM-CSF) was performed. None of these parameters showed a correlation with the half-time of disappearance of chromosomal aberrations. For the individuals who had received less than 1 Gy the disappearance of aberrations was slower, with a half-time of 160 days during the period up to 470 days after exposure. Mean disappearance functions of unstable chromosome aberrations were inferred, to be applied in accident situations in which there is a blood sampling delay.
Assuntos
Aberrações Cromossômicas , Linfócitos/efeitos da radiação , Liberação Nociva de Radioativos , Adolescente , Adulto , Brasil , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
Consumption of maté, a tea-like infusion of the herb Ilex paraguariensis, is common in South America. Drinkers have high risks of upper aerodigestive tract cancers, but it is conceivable that this high risk may be attributable to confounding by smoking alcohol, and other exposures. To test this hypothesis, we analyzed the data from a case-control study of upper aerodigestive tract cancers conducted in Southern Brazil. We matched noncancer controls (N = 756) to cases (N = 378) on the basis of age, sex, and period of admission. We estimated the effect of mateé consumption by conditional logistic regression with adjustment for smoking, alcohol, sociodemographics, and several dietary items, considered as confounders. The unadjusted relative risk (RR) for all upper aerodigestive tract cancers was 2.1 [95% confidence interval (CI) = 1.6-2.7]. Some excess risk persisted after adjustment for potential confounders (RR = 1.6; 95% CI = 1.2-2.2). Most of the excess risk for maté drinkers was for oral (RR = 1.9; 95% CI = 1.1-3.3) and laryngeal (RR = 2.2; 95% CI = 2.2; 95% CI = 1.1-4.5) cancers. There was no evidence of associations with coffee and tea drinking. We conclude that the association of maté consumption with upper aerodigestive tract cancer risk is unlikely to result from insufficient control of confounding by critical exposures. Owing to its high prevalence in Southern South America, maté drinking may be linked to as many as 20% of all cases occurring in this region.