RESUMEN
Squamous cell carcinoma (SCC) and adenocarcinoma (ADC) are the two main histological types of esophageal cancer. Southern Brazil has the highest rates of esophageal cancer in South America, and the most prevalent subtype of esophageal cancer has been SCC. This study assessed the trend changes in the histological types of esophageal cancer, in a 20-year period, in the central region of Rio Grande do Sul State, Brazil. We searched all cases of esophageal cancer from 1993 to 2012 by their histological diagnosis, grouping the patients in 4-year time periods to evaluate time trends. Among 18 441 upper gastrointestinal endoscopies we identified 686 cases of esophageal cancer. Histological study confirmed the diagnosis of SCC in 640 (93.3%) patients and ADC in 46 (6.7%). Overall, 522 men were diagnosed with esophageal carcinoma; from these, 489 (93.6%) presented SCC, and 33 (6.3%) ADC. Among women, 164 had the diagnosis of esophageal cancer, 151 (92%) SCC, and 13 (7.9%) ADC. The proportion found among men and women was 3.1:1, respectively. The prevalence rate of esophageal cancer, along a 20 year-period, remained stable, as well as the rates of SCC and ADC. SCC was the most common type of esophageal cancer, and ADC presented very low prevalence.
Asunto(s)
Adenocarcinoma/epidemiología , Carcinoma de Células Escamosas/epidemiología , Neoplasias Esofágicas/epidemiología , Anciano , Brasil/epidemiología , Endoscopía del Sistema Digestivo , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Masculino , Persona de Mediana Edad , Crecimiento Demográfico , Prevalencia , Centros de Atención TerciariaRESUMEN
Bacillus thuringiensis harbors genes encoding Cry proteins found in chromosomes or plasmids of different sizes (4-150 Mb). Although the smaller plasmids are more abundant in B. thuringiensis, their specific function is unknown. As for the megaplasmids, their main recognized function is to harbor cry genes, although the sequencing of some of these plasmids indicates the occurrence of other important genes. This work used a new protocol for practical and rapid extraction of plasmid DNA in order to characterize the plasmid patterns of Brazilian strains belonging to Embrapa Milho e Sorgo research center B. thuringiensis bank. We tried to further assess the relationship of plasmid patterns with strains belonging to the same serovars and strains causing 100% and no mortality to Spodoptera frugiperda (J.E. Smith) larvae. It was possible to characterize 59 strains based on the migration of bands in agarose gel. Strains belonging to the same serovars showed different plasmid sizes (from 1,636 bp to 23,200 bp), with the exception of two strains belonging to serovar galleriae. The strain T09 Bt tolworthi showed a plasmid migration pattern identical to strains belonging to serovar galleriae. Plasmid patterns differed for 46 strains, confirming that this is a useful tool to discriminate specific strains. However, it was not possible to associate the plasmid pattern or the occurrence of particular plasmids with the pathogenicity of a given species towards S. frugiperda larvae.
Asunto(s)
Bacillus thuringiensis/genética , Lepidópteros/microbiología , Plásmidos/genética , Animales , Control Biológico de Vectores/métodosRESUMEN
Gastroesophageal reflux disease (GERD) is a major risk factor for the development of esophageal adenocarcinoma (ACE). Many molecular alterations occur in esophageal carcinogenesis, yet the exact mechanism of ACE development remains unknown. This study aims to determine p53 protein and Ki-67 expression in esophageal mucosa of patients with GERD and study the correlation between these markers and the progression from normal squamous epithelium to esophagitis, columnar epithelium with or without intestinal metaplasia and ACE. We analyzed p53 protein and Ki-67 expression in biopsies of 200 patients with GERD and 35 patients with ACE. Those biopsies were classified into five groups: (i) G1 normal squamous epithelium (58); (ii) G2 esophagitis (80); (iii) G3 columnar epitheliums without intestinal metaplasia (30); (iv) G4, columnar epitheliums with intestinal metaplasia (32); and (v) G5 ACEs (35). p53 protein overexpression was found in 7% (4) of G1, 37.5% (30) of G2, 30% (9) of G3, 62.5% (20) of G4, and 71.4% (25) of G5 (p < 0.001). Ki-67 index increased according to the severity of histopathological diagnoses. Ki67 index was 21.3 +/- 19.5% in G1, 38.8 +/- 24.9% in G2, 37.7 +/- 26.3% in G3, 52.8 +/- 24.6% in G4, and 57.1 +/- 25.1% in G5 (P < 0.001). Linear correlation between p53/Ki67 expression and the multistep progression from squamous epithelium to ACE was observed (P < 0.001 and P < 0.05). Our results indicate that overexpression of p53 and increased Ki-67 could be associated with the development and progression to ACE in patients with GERD.
Asunto(s)
Adenocarcinoma/metabolismo , Esófago de Barrett/metabolismo , Neoplasias Esofágicas/metabolismo , Esófago/metabolismo , Antígeno Ki-67/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Adenocarcinoma/patología , Adulto , Esófago de Barrett/patología , Progresión de la Enfermedad , Endoscopía Gastrointestinal , Neoplasias Esofágicas/patología , Esofagitis/patología , Esófago/patología , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Inmunohistoquímica , Membrana Mucosa/metabolismo , Estudios ProspectivosAsunto(s)
Enfermedades del Esófago/diagnóstico , Estenosis Esofágica/diagnóstico , Esofagoscopía , Tuberculosis Gastrointestinal/diagnóstico , Adulto , Biopsia , Broncoscopía , Diagnóstico Diferencial , Enfermedades del Esófago/patología , Estenosis Esofágica/patología , Esófago/patología , Humanos , Masculino , Tomografía Computarizada por Rayos X , Tuberculosis Gastrointestinal/patología , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/patologíaRESUMEN
Squamous cell carcinoma of the esophagus (SCCE) is diagnosed late and carries a poor prognosis. Biomarkers such as p53 protein expression may be present in the esophageal mucosa long before esophageal symptoms or lesions appear and may point toward early diagnosis. Asymptomatic subjects at high risk for SCEE (consumption of more than 80 g of ethanol and 10 cigarettes/day for at least 10 years) underwent upper gastrointestinal endoscopy with biopsies of the esophageal mucosa, and expression of p53 protein was compared with conventional histologic findings. In 182 subjects studied, p53 protein was expressed in a stepwise fashion according to the severity of the histologic findings: normal mucosa (12/103 or 11.7%), mild chronic esophagitis (6/43 or 14%), moderate chronic esophagitis (4/18 or 22.2%), severe chronic esophagitis (1/3 or 33.3%), low-grade dysplasia (4/11 or 36.4%), high-grade dysplasia (2/2 or 100%), and squamous cell carcinoma (2/2 or 100%) (P=0.00025). The odds ratio and confidence intervals were calculated by logistic regression, with multivariate adjustment for potentially confounding variables. The risk for p53 expression was twofold for moderate and severe chronic esophagitis and 10-fold for dysplasia and cancer (P=0.001). p53 protein was expressed not only in cancerous lesions, high-grade and low-grade dysplasia, as expected, but also in mucosa considered normal or with chronic esophagitis using conventional histology. Smokers and alcohol drinkers with normal mucosa or chronic esophagitis that express p53 protein may represent an unrecognized subgroup of individuals that may benefit from surveillance. Follow-up studies of these asymptomatic subjects and molecular analysis of the p53 gene are needed to clarify this point.
Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/patología , Proteína p53 Supresora de Tumor/análisis , Adulto , Anciano , Alcoholismo , Biopsia con Aguja , Estudios de Casos y Controles , Técnicas de Cultivo , Esofagoscopía , Femenino , Humanos , Inmunohistoquímica , Modelos Logísticos , Masculino , Persona de Mediana Edad , Membrana Mucosa/patología , Análisis Multivariante , Estadificación de Neoplasias , Probabilidad , Estudios Prospectivos , Valores de Referencia , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad , Fumar/efectos adversos , Análisis de SupervivenciaRESUMEN
BACKGROUND AND STUDY AIMS: Squamous cell carcinoma of the esophagus (SCCE) becomes symptomatic at a late stage when the disease is already advanced, and this contributes to its poor prognosis. Esophagoscopy of asymptomatic individuals exposed to known risk factors associated with the development of this cancer may facilitate the diagnosis of early cancerous or precancerous lesions; however, conventional esophagoscopy is not accurate enough. The aim of this study was to measure the value of Lugol chromoendoscopy of the esophagus (LCE) as an endoscopic technique to detect dysplasia in patients at risk. PATIENTS AND METHODS: We studied 190 male patients older than 35 attending an outpatient unit for alcoholics who consumed more than 80g of alcohol, more than 10 cigarettes and more than 500 ml 'maté' (a hot infusion of herbs) per day over 10 years. All underwent conventional upper gastrointestinal endoscopy followed by LCE, a spraying of Lugol 3% on the entire esophagus. All patients denied dysphagia. Biopsies were obtained from any unstained areas larger than 5mm and also from stained areas in all individuals. Biopsies were analyzed independently by two pathologists unaware of the biopsy sites. All conventional esophagoscopies showed normal mucosa, except for two suspicious small elevated lesions, confirmed histologically to be SCCE. These two cases were excluded from the statistical analysis. RESULTS: The LCE found unstained areas in 23 patients and a uniformly stained esophageal mucosa in the remaining 165. Biopsies taken from these 23 unstained areas showed dysplasia in six (two high grade and four low grade), and the ones from the 165 stained areas taken at the middle esophagus showed low-grade dysplasia in seven. There was a high prevalence (6.9%) of dysplastic lesions in these individuals and occult dysplasia was significantly more frequent in unstained than stained areas (p = 0.0017). LCE showed a sensitivity of 46%, a specificity of 90%, a positive predictive value of 26% and a negative predicitve value of 96% when unstained areas were compared to stained ones. Agreement between two independent pathologists was high, with a kappa coefficient of 0.64. CONCLUSION: We concluded that individuals who abuse alcohol, smoke and consume 'maté' have a high prevalence of dysplastic lesions that can be better detected by LCE. Esophagi with unstained areas had an eight-fold higher chance of revealing dysplasia than the uniformly stained ones. LCE is an easy and inexpensive method. It improves the detection of dysplasia and should be added to conventional upper GI endoscopy in patients at risk for SCCE.
Asunto(s)
Alcoholismo/complicaciones , Carcinoma de Células Escamosas/patología , Colorantes , Neoplasias Esofágicas/patología , Esofagoscopía , Esófago/patología , Yoduros , Lesiones Precancerosas/patología , Bebidas , Biopsia , Humanos , Masculino , Persona de Mediana Edad , Membrana Mucosa/patología , Factores de Riesgo , Sensibilidad y Especificidad , FumarRESUMEN
Diagnosis of squamous cell carcinoma of the esophagus is usually late. Staining of the mucosa with Lugol's solution during endoscopy has been suggested to identify early cancer/dysplasia and may improve prognosis. Lugol was tested during endoscopy in 96 asymptomatic subjects at risk for this tumor, who were found to have atypias after exfoliative cytology in southern Brazil. Biopsies were obtained in Lugol's 'stained' and 'unstained' areas in the esophageal mucosa and the histologic results were compared. 'Unstained' areas were present in 64 (66.7%) instances: 44 'unstained' areas over mucosa with normal appearance revealed seven dysplasias (four high and three low grade), whereas 20 'unstained' areas with visible lesions contained only one dysplasia (low grade). 'Stained' areas in 96 (100%) subjects showed two additional dysplasias (one high and one low grade). In this study, Lugol 'unstained' areas were of great value for detection of dysplasias (sensitivity = 80%; specificity = 63%; p = 0.01, Fisher's exact test; CI = 95%; odds ratio = 6.7).