Fecal occult blood test and flexible rectosigmoidoscopy: tools for the screening of colorectal neoplasms in asymptomatic patients

Abstract

Abstract Purpose To assess the feasibility and effectiveness of the fecal occult blood test (FOBT) and flexible rectosigmoidoscopy (RSS), as tools used in the CRC screening, in asymptomatic patients, from 50 years of age. Methods The study is transversal and presents a sample of 102 individuals. The FOBT used was the guaiaco, FECA-CULT® method, held at a single time, in feces collected from a complete evacuation. Individuals, who presented the positive FOBT, were sent to colonoscopy complement, although this is not primary variable examined in this study. All subjects underwent to flexible RSS, after bowel preparation, using a solution of sodium phosphate monobasic monohydrate and dibasic sodium phosphate heptahydrate. Results Individuals showed minimum age of 50 years and maximum 82 years, 61.6 years average and standard deviation +8.1. Of the 102 individuals, 42 (41%) belong to the males, whereas 60 (58.8%) female. The FOBT presented 10 positive cases (9.8%) (IC 95%: 4.8–17.3%) and 92 negative cases (90.2%) (IC 95%; 82.7–95.2%). The FOBT was effective at 2.9% and presented false-positive result in 6.9%. The result of the FBOT association with flexible RSS showed that 70% of neoplastic polyps showed no bleeding. Its sensitivity was 30% (IC 95%: 0.00–63.40%), the value of the relative risk was 3.94 (IC 95%: 1.20–12.89) and 5.20 valued odds ratio (IC 95%: −23.15 to 1.21). The specificity was 92.40% (IC 95%: 86.43–98.35%). The flexible RSS detected 15 polyps, among which, after histopathological study, 10 were neoplastic, being 09 adenomatous polyps (60%) and 01 malignity (6.7%) (IC 95%: 0.20–31.90%) and 05 non-neoplastic polyps (33.3%), and 03 inflammatory polyps (20%) (IC 95%: 4.3–48.1%) and 02 hyperplastic polyps (13.3%) (IC 95%: 1.7–40.5%). Neoplastic polyps were present in 60% of individuals over 60 years of age. Among the adenomatous polyps, the adenomatous polyp tubular prevalence is 53.33%. Among the 102 individuals, flexible RSS detected 09 adenomatous polyps (8.82%) and 01 (0.98%) malignity polyp. Conclusion The tools FOBT and flexible RSS presented feasibility and, when associated demonstrated statistical significance in detecting polyps in general and important clinical significance on the detection of adenomatous polyps and colorectal cancer.