-Context -The appearance of adenomas and their progression to adenocarcinomas is the result of an accumulation of genetic changes in cells of the intestinal mucosa inherited or acquired during life. Several proteins have been studied in relation to the development and progression of colorectal cancer, including tumor protein p53 (p53) and antigen identified by monoclonal antibody . Objective -To evaluate the expression of p53 and Ki-67 in colorectal adenomas and correlate the observed levels with clinical and pathologic findings. Method -The sample consisted of 50 adenomatous polyps from patients undergoing colonoscopy. After performing polypectomy, polyps were preserved in a formalin solution with 10% (vol./vol.) phosphate buffer, submitted for routine preparation of sections and slides and stained with hematoxylin and eosin. For each adenoma we then performed immunohistochemistry to detect specific p53 and Ki-67 proteins using a streptavidin-biotin-peroxidase enzyme immunoassay.Results -p53 was detected in 18% of the adenomas. The average Ki-67 protein index (i.Ki-67) was 0.49. A statistically significant difference was observed in p53 (P = 0.0003) and Ki-67 (P = 0.02) expression between adenomas with low-and high-grade dysplasia, particularly for p53. The expression of Ki-67 was greater in rectal adenomas than in colic adenomas (P = 0.02). No relationship was found between the expression of the two proteins in the sample. Conclusion -The p53 protein is expressed in a proportion of adenomas, while the Ki-67 protein was expressed in all adenomas. The expression of p53 was higher in adenomas with high-grade dysplasia. The expression of Ki-67 was higher in rectal adenomas and in adenomas with high-grade dysplasia. HEADINGS -Colorectal neoplasm. Tumor suppressor protein p53. Ki67-antigen. Immunohistochemistry.
INTRODUCTION: Colorectal cancer (CRC) is an important pathology characterized by tumors in colorectal segments. Colonoscopy is the gold standard of CRC detection, but it is very expensive. Then, new methods are required for CRC screening to reduce mortality and improve the cost-benefit ratio. Objective: Evaluate the efficacy of a questionnaire (QSSA) based on signs and symptoms of CRC. METHODS: The QSSA was answered by 40 patients, before the colonoscopy procedure. The patients were divided into two groups: group I, with 20 patients showing positive result in the questionnaire, and group II, with 20 people showing negative result in the questionnaire. Colonoscopy was considered positive when presenting neoplasm or its precursor. The result was statistically analyzed by Fischer's exact test and sensitivity calculation. RESULTS: The results showed 14 positive and 26 negative colonoscopies. Group I had 9 positive and 11 negative colonoscopies and Group II, 5 positive and 15 negative (p=0.20) colonoscopies. The questionnaire presented sensitivity of 64.2%. CONCLUSION: The use of this questionnaire based on signs and symptoms of CCR alone was not effective in CCR screening. INTRODUÇÃO: O câncer colorretal (CCR) é uma importante afecção caracterizada pela presença de tumores localizados no colón ou reto. A colonoscopia, padrão ouro na detecção do CCR, demanda alto custo. Assim, há necessidade de métodos de triagem eficazes, visando um melhor custo beneficio na diminuição da mortalidade do CCR. OBJETIVO: Avaliar a efetividade de um questionário de sinais, sintomas e antecedentes (QSSA) em predizer o CCR. Métodos: O QSSA foi aplicado a 40 pacientes, momentos antes da realização do exame colonoscópico, no intuito de compor dois grupos: grupo I formado pelos 20 primeiros que apresentassem o QSSA positivo, e grupo II formado pelos 20 primeiros com QSSA negativo. A colonoscopia positiva foi aquela com achado de neoplasia ou lesões precursoras do CCR. O resultado foi submetido à análise estatística através do Teste Exato de Fischer e do cálculo da sensibilidade, especificidade, acurácia e valores preditivos positivos e negativos. RESULTADO: Observaram-se 14 colonoscopias positivas e 26 colonoscopias negativas, assim distribuídas: grupo I, 9 positivas e 11 negativas; grupo II, 5 positivas e 15 negativas (p=0,20). O questionário apresentou sensibilidade de 64,2%. CONCLUSÃO: A utilização de um questionário de sinais, sintomas e antecedentes usado isoladamente não mostrou eficácia no rastreamento de lesões neoplásicas
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.