Prevenção do câncer colorretal (CCR) : avaliação da utilidade da pesquisa de sangue oculto nas fezes previamente à colonoscopia.

Abstract

INTRODUCTION: Colorectal cancer (CRC) is the third most frequent malignant neoplasm in our country, with an incidence of ascending disease, mainly in the southern and southeastern states of Brazil, with an expectation of 29 new cases per 100,000 inhabitants (INCA 2016 ). CRC has the characteristic, 95% of the time, of developing from an adenomatous polyp, which remains benign for a variable time until it acquires the malignant pattern of adenocarcinoma. This pre-malignant period allows secondary prevention to be performed when resection of these polyps is performed. Primary CRC prevention is based on lifestyle adequacy, which takes into account food care, obesity control, physical activity, diabetes mellitus control, and alcohol consumption reduction. CRC screening targets secondary prevention and early diagnosis. There are several tests available to perform this screening, and there is no definition in the current literature of the ideal method or strategy, especially for employment in large population groups and especially in the unassisted or vulnerable population groups. In Brazil there is no CRC prevention program, organized by the Ministry of Health and the medical associations of specialties related to CRC, recommend the use of colonoscopy as a standard method. OBJECTIVE: The present study aims to investigate the following problem: is the fecal occult blood test by the immunochemical method as a step prior to colonoscopy an effective strategy in the prevention of colorectal cancer? ARTICLE I: OBJECTIVE: To evaluate the usefulness of fecal occult blood test by the immunochemical method (FIT) as a screening step for colonoscopy in colorectal cancer prevention (CRC); METHODS: Cross-sectional, observational and prospective study with patients between 40 and 80 years of age, referred for CRC screening by colonoscopy, to an endoscopy clinic in Santa Maria, RS. Asymptomatic and non-colorectal patients, on the appointment of the colonoscopy, were asked to participate in the study, performing FIT, before colonoscopy. At the time of the colonoscopy, data from the tests were interviewed and collected. RESULTS: Our sample was 93 patients, 67 women, with a mean age of 63.1 ± 9.9 years. The FIT was positive in 51 patients (54.8%). We found 38 cases without adenomatous polyps or adenocarcinoma, 49 with adenomatous polyps and 6 adenocarcinomas. As for polyps, the mean polyp size was 8.3 ± 15.0 cm and the majority of the cases were polyps less than 5 mm (59.1%), followed by polyps between 5 and 19 mm (32%) and polyps of 20mm or greater (8.1%). There was a significant correlation between polyp size and FIT positivity (r = 0.296, p = 0.004). There was a correlation between the number of polyps / tumor presence with FIT positivity (r = 0.288; p = 0.005). We had 23 cases of normal colonoscopy, 15 with non-neoplastic findings, 26 with polyps, 23 with polyps and non-neoplastic findings and 6 with adenocarcinomas. We found 34 patients with only one polyp and 15 with two or more polyps. There was an association between pre-malignancy / tumor presence and FIT positivity (p = 0.049). CONCLUSION: The FIT test had concordant results with the colonoscopic findings, regarding the presence of advanced adenomas, adenocarcinomas, or the presence of two or more polyps, not maintaining this agreement with the presence of minor adenomas. Also, it was not interfered with by non-neoplastic findings in colonoscopy, showing an alternative method of low cost and good adherence for population screening. ARTICLE II: OBJECTIVE: To review the literature of classic articles on the various factors related to CRC and a systematic review related to CRC and lifestyle, in which the factors related to dietary habits, physical activity, alcohol consumption, smoking and obesity;METHODS: We searched data from PubMed, from the last 5 years in human studies, written in English, Spanish or Portuguese, with full text of free access. We selected review articles, meta-analysis, guidelines, randomized controlled trials, multicenter trials, clinical and comparative studies. We found 149 articles, of which after analysis were selected 27 articles; RESULTS: An studies. We found 149 articles, of which after analysis were selected 27 articles; RESULTS: An association between CRC and dietary habits was found, with risk factors being low fiber utilization 11 and high energy intake, while the use of specific diets such as Mediterranean diet and caffeine intake were protective factors for CRC. Alcohol consumption was also positively related, especially in heavy drinkers, who had an increased incidence of distal CRC in the gut. Smoking also showed a positive relationship with CRC, and this risk remained increased for 25 years after smoking cessation. Sedentary lifestyle was also associated with CRC risk. Obesity wasa risk factor for CRC and the presence of metabolic syndrome was strongly related to the development of pre-neoplastic lesions; CONCLUSION: These results support the need for primary prevention, stimulating healthy habits and controlling related pathologies, such as diabetes.