Relação entre infecção pelo helicobacter pylori linhagem cagA-positiva e risco de câncer gástrico

Introdução: O câncer gástrico é a segunda causa mais comum de mortes relacionadas à neoplasia no mundo. Apesar de o Helicobacter pylori ser classificado como um carcinógeno grupo I, a presença dessa infecção não é um fator que, isoladamente, possa levar ao desenvolvimento de câncer gástrico, sendo que, entre as possíveis justificativas, está a existência de diferentes linhagens de Helicobacter pylori com diferentes graus de virulência. Material e métodos: Foram pareados, por sexo e por idade, 29 pacientes com adenocarcinoma gástrico distal e 58 pacientes submetidos à endoscopia digestiva alta, cujo diagnóstico não fosse câncer gástrico. Em todos os pacientes, foi pesquisado o status da infecção por Helicobacter pylori (através de teste da urease, histopatológico e PCR para os genes ureA e 16S-rRNA), além de determinação do status de infecção por linhagem cagApositiva do Helicobacter pylori (através de PCR para o gene cagA). Resultados: A porcentagem de pacientes com infecção por Helicobacter pylori foi idêntica nos dois grupos (68,9%). Quando avaliamos a presença de infecção pelo Helicobacter pylori linhagem cagA-positiva, verificamos que a freqüência desta é significativamente mais alta no grupo caso, quando comparado com o grupo controle, ocorrendo em 62,1% e 29,3% desses, respectivamente (OR=3,95; IC 95% 1,543-10,096). Ao avaliarmos apenas os pacientes Helicobacter pylori-positivos, a freqüência de infecção por linhagem cagApositiva também é mais elevada no grupo caso (90%), quando comparado com o grupo controle (42,5%) (OR=12,18; IC 95% 2,71-52,9). Conclusões: Existe associação entre infecção por Helicobacter pylori linhagem cagApositiva e adenocarcinoma gástrico distal, independente do status de infecção pelo Helicobacter pylori.Background: Gastric cancer is the second most common cause of cancer related death worldwide. Although Helicobacter pylori has been classified by the World Health Organization as a class I carcinogen, the presence of the infection is not a factor that alone is able to lead to gastric cancer, and one of the possible explanations for this is the existence of different strains of Helicobacter pylori with different degrees of virulence. Materials and methods: 29 patients with gastric cancer were matched by sex and age (+/- 5 years) with 58 patients without gastric cancer, submitted to upper gastrointestinal endoscopy. All patients were evaluated for the status of infection by Helicobacter pylori (through urease test, histological analysis and PCR for the genes ureA and 16S-rRNA) and for the status of infection by cagA-positive strain (through PCR for the gene cagA) Results: evaluating the presence of infection by cagA-positive Helicobacter pylori, it was verified that the rate of infection was significantly higher in the group with gastric cancer when compared with the matched controls, occurring in 62,1% and 29,3%, respectively (OR=3,95; IC 95% 1,543-10,096). Evaluating only Helicobacter pylori-positive patients, the rate of infection by cagA-positive strains was also significantly higher in the group with gastric cancer (OR=12,18; IC 95% 2,71-52,9). Conclusions: There is association between cagA-positive Helicobacter pylori and risk of gastric cancer, independent of the status of infection by Helicobacter pylori

Relação entre infecção pelo helicobacter pylori linhagem cagA-positiva e risco de câncer gástrico

Introdução: O câncer gástrico é a segunda causa mais comum de mortes relacionadas à neoplasia no mundo. Apesar de o Helicobacter pylori ser classificado como um carcinógeno grupo I, a presença dessa infecção não é um fator que, isoladamente, possa levar ao desenvolvimento de câncer gástrico, sendo que, entre as possíveis justificativas, está a existência de diferentes linhagens de Helicobacter pylori com diferentes graus de virulência. Material e métodos: Foram pareados, por sexo e por idade, 29 pacientes com adenocarcinoma gástrico distal e 58 pacientes submetidos à endoscopia digestiva alta, cujo diagnóstico não fosse câncer gástrico. Em todos os pacientes, foi pesquisado o status da infecção por Helicobacter pylori (através de teste da urease, histopatológico e PCR para os genes ureA e 16S-rRNA), além de determinação do status de infecção por linhagem cagApositiva do Helicobacter pylori (através de PCR para o gene cagA). Resultados: A porcentagem de pacientes com infecção por Helicobacter pylori foi idêntica nos dois grupos (68,9%). Quando avaliamos a presença de infecção pelo Helicobacter pylori linhagem cagA-positiva, verificamos que a freqüência desta é significativamente mais alta no grupo caso, quando comparado com o grupo controle, ocorrendo em 62,1% e 29,3% desses, respectivamente (OR=3,95; IC 95% 1,543-10,096). Ao avaliarmos apenas os pacientes Helicobacter pylori-positivos, a freqüência de infecção por linhagem cagApositiva também é mais elevada no grupo caso (90%), quando comparado com o grupo controle (42,5%) (OR=12,18; IC 95% 2,71-52,9). Conclusões: Existe associação entre infecção por Helicobacter pylori linhagem cagApositiva e adenocarcinoma gástrico distal, independente do status de infecção pelo Helicobacter pylori.Background: Gastric cancer is the second most common cause of cancer related death worldwide. Although Helicobacter pylori has been classified by the World Health Organization as a class I carcinogen, the presence of the infection is not a factor that alone is able to lead to gastric cancer, and one of the possible explanations for this is the existence of different strains of Helicobacter pylori with different degrees of virulence. Materials and methods: 29 patients with gastric cancer were matched by sex and age (+/- 5 years) with 58 patients without gastric cancer, submitted to upper gastrointestinal endoscopy. All patients were evaluated for the status of infection by Helicobacter pylori (through urease test, histological analysis and PCR for the genes ureA and 16S-rRNA) and for the status of infection by cagA-positive strain (through PCR for the gene cagA) Results: evaluating the presence of infection by cagA-positive Helicobacter pylori, it was verified that the rate of infection was significantly higher in the group with gastric cancer when compared with the matched controls, occurring in 62,1% and 29,3%, respectively (OR=3,95; IC 95% 1,543-10,096). Evaluating only Helicobacter pylori-positive patients, the rate of infection by cagA-positive strains was also significantly higher in the group with gastric cancer (OR=12,18; IC 95% 2,71-52,9). Conclusions: There is association between cagA-positive Helicobacter pylori and risk of gastric cancer, independent of the status of infection by Helicobacter pylori

Relationship between caga-positive Helicobacter pylori infection and risk of gastric cancer: a case control study in Porto Alegre, RS, Brazil

CONTEXT: Gastric cancer is the second most common cause of cancer related death worldwide. Although Helicobacter pylori has been classified as a class I carcinogen, the presence of infection is not a factor that alone is able to lead to gastric cancer, and one of the possible explanations for this is the existence of different strains of H. pylori with different degrees of virulence. OBJECTIVES: To investigate the association between cagA-positive H. pylori and gastric cancer, using polymerase chain reaction (PCR) for the detection of this bacterial strain. METHODS: Twenty-nine patients with gastric cancer were matched by sex and age (± 5 years) with 58 patients without gastric cancer, submitted to upper gastrointestinal endoscopy. All patients were evaluated for the status of infection by H. pylori (through urease test, histological analysis and PCR for the genes ureA and 16SrRNA) and by cagA-positive strain (through PCR for cagA gene). RESULTS: Evaluating the presence of infection by cagA-positive H. pylori, it was verified that the rate of infection was significantly higher in the group with gastric cancer when compared with the matched controls, occurring in 62.1% and 29.3%, respectively (OR = 3.95; CI 95% 1.543-10.096). CONCLUSIONS: There is an association between cagA-positive H. pylori strain and risk of gastric cancer

ENDOSCOPIC ULTRASOUND IN THE EVALUATION OF UPPER SUBEPITHELIAL LESIONS

BackgroundEndoscopic ultrasound is considered the best imaging test for the diagnosis and evaluation of subepithelial lesions of the gastrointestinal tract.ObjectiveThe present study aims to describe the endosonographic characteristics of upper gastric subepithelial lesions and our experience using endoscopic ultrasound for evaluation of such lesions.MethodsRetrospective data study of 342 patients who underwent endoscopic ultrasound evaluation of subepithelial lesions.ResultsLesions of the fourth layer were more common in the stomach (63.72%) than in the esophagus (44.68%) and duodenum (29.03%). In stomach, 81.1% of the lesions ≥2 cm, and 96.5% ≥3 cm, were from the fourth layer. Endosonographic signs that could be related to malignant behavior, such as irregular borders, echogenic foci, cystic spaces and/or size greater than 3 cm were identified in 34 (15.81%) lesions at the first endoscopic ultrasound evaluation. Endoscopic ultrasound-fine needle aspiration did the diagnosis in 21 (61.76%) patients who were submitted a puncture. Three (12.0%) lesions of 25 who were submitted to regular endoscopic ultrasound surveillance increased the size.ConclusionStomach is the organ most affected with subepithelial lesions of the gastrointestinal tract and the fourth layer was the most common layer of origin. More than 80% of gastric subepithelial lesions from the fourth layer are ≥2 cm. Endoscopic ultrasound evaluation of subepithelial lesions has been very important for stratification into risk groups and to determine the best management