Teste de sangue oculto nas fezes e retossigmoidoscopia flexível: ferramentas para o rastreamento de neoplasias colorretais em pacientes assintomáticos.

Abstract

The colorectal cancer (CRC) is the third most common cancer in the world and the second leading cause of mortality in the United States. In Brazil, the CRC is the fourth place of incidence among men and the third place among women. Objective Evaluate the factibility and the efficacy of fecal occult blood testing (FOBT) and of flexible rectosigmoidoscopy (RS), as tools used in the CRC screening, in asymptomatic patients. Methods - The study is a transversal one and presents a sample of 102 individuals from 50 years old on. The FOBT used was the guaiac, FECA-CULT® method, performed only once in faeces collected from a complete bowel movement. The individuals, who presented the positive FOBT, were sent to complementary colonoscopy, although it is not a method of this study. The whole individuals were undertaken to RS, after bowel preparation using monobasic sodium phosphate monohydrate and dibasic sodium phosphate heptahydrate solution. Results - The subjects presented minimum age of 50 years old and maximum of 82 years old, average of 61,6 years old and standard deviation of + 8,1. Among 102 subjects, 42 (41%) are male and 60 (58,8%) are female. The FOBT presented 10 positive cases (9,8%) (CI 95%: 4,8%-17,3%) and 92 negative cases (90,2%) (CI 95%: 82,7%-95,2%). The FOBT was efficient in 2,9% and presented false- positive results in 6,9%. The result from the association FOBT with flexible RSS showed that 70% of neoplasic polyps did not present bleeding. Its sensitivity was 30% (CI 95%: 0,00%-63,40%), the relative risk value was 3,94 (CI 95%: 1,20- 12,89) and odd ratio was 5,20 (CI 95%: 1,21-23,15). The specificity was 92,40% (CI 95%: 86,43%-98,35%). The RS detected 15 polyps among witch, after a histopathological study, 10 were neoplastic, being 09 adenomatous polyps (60%) and 01 malignized polyp (6,7%) (CI 95%: 0,20%-31,90%) and 05 non-neoplastic polyps (33,3%), being 03 inflammatory polyps (20%) and 02 hyperplastic polyps (13,3%) (IC 95%: 1,7%-40,5%). The neoplastic polyps were presented in 60% of the individuals over sixty years old. Among adenomatous polyps, there was a predominance of tubular adenomatous polyps in 53,33%. Among the 102 individuals, the RS detected 09 adenomatous polyps (8,82%) and 01 malignized polyp (0,98%). Conclusion - The tools FOBT and flexible RSS presented factibility and that, when associated, presented statistic significance to detect polyps and important clinical significance to detect adenomatous polyps and colorectal cancer.