Summary Objective To determine the impact of the quality of colonoscopy examination for colorectal cancer screening. Methods Retrospective observational study ofmedical records from patients treated at the endoscopy and colonoscopy service of Hospital Universitário Evangélico Mackenzie (Curitiba, PR, Brazil) from January 2019 to January 2020. Results The analysis was based on 337 medical records from patients with adenomas identified during colonoscopy, and 1,385 medical records from patients without adenomas. The estimated occurrence rate of diagnosis of adenoma during colonoscopy in the target population of the study was of 19.6%, with a 95% confidence interval ranging from 17.7 to 21.5%. Of the 337 patients with adenoma, 136 (40.4%) presented the advanced form. Statistical analysis indicated a significant association between the quality of colonoscopy preparation and test completion. Conclusion The quality of colonoscopy images is a critical factor for colorectal cancer screening, as it leads to higher rates of adenoma detection and test completion.

ABSTRACT BACKGROUND: Colonoscopy is the gold standard for the diagnosis and treatment of adenomas. It is related with decreased colorectal cancer incidence and mortality. However, an important problem is missed colorectal adenoma. All efforts should be undertaken to reduce this rate. Enhancing imaging technologies including electronic chromoendoscopy and magnification has been increasingly adopted for improving the colorectal neoplasia detection rate and the detailed study of its surface, as well. I-scan images (Pentax, Tokyo, Japan) provides virtual chromoendoscopy in real-time during the examination to view the surface pattern, highlighting the microvasculature of the neoplastic lesion. The evidence on the impact of the use of I-scan on the colorectal adenoma detection rate is scarce. OBJECTIVE: To evaluate whether the use of I-scan has impact on the adenoma miss rate (AMR) of screening colonoscopy exams. METHODS: Observational and prospective study conducted by monitoring patients over 50 years undergoing colonoscopy. There were two groups: Group 1 - first inspection with standard high-definition white-light (HDWL) followed by a second inspection with I-scan 1; Group 2 - first inspection with I-scan 1 followed by a second inspection with standard HDWL. The primary outcome was the AMR from the first exam, calculated with the number of adenomas detected in the second exam, divided by the total number of adenomas detected in both exams. RESULTS: A total of 85 patients participated in the study. 14 were excluded, with a final sample of 71 patients, in the Group 1, 34 patients, and the Group 2, 37. A total of 58 adenomas were detected, 40 in the first inspection (20 in each group) and 18 in the second inspection in group 1. The overall AMR was higher for the Group 1 than the Group 2 (47.4% vs 0% P=0.0002). CONCLUSION: The use of I-scan 1 during colonoscopy exam reduces the AMR.

OBJETIVO: Analisar retrospectivamente o resultado do estudo anatomopatológico de polipectomias colonoscópicas realizadas no Setor de Endoscopia da Faculdade de Medicina de Botucatu - UNESP durante os anos de 2002 e 2003. Material e Métodos: Estudamos retrospectivamente, a partir de procedimentos colonoscópicos realizados em nosso serviço, as características dos pólipos retirados: tamanho, localização e distribuição, bem como o motivo da indicação do mesmo e o resultado do estudo anatomopatológico. RESULTADOS: Num total de 100 polipectomias colonoscópicas realizadas em 75 pacientes, observamos que 63% dos pólipos localizava-se em reto e sigmóide e 15,8% no cólon descendente; o estudo anátomopatologico evidenciou que a grande maioria tinha características adenomatosas (54%). A idade dos pacientes variou entre 6 e 92 anos, não havendo predominância quanto ao sexo; a principal indicação para a realização de colonoscopia foi sangramento. CONCLUSÃO: Constatamos o importante papel diagnóstico e terapêutico das colonoscopias no que diz respeito ao câncer colorretal; os achados demonstram que, em nossa casuística, a maioria os pólipos colônicos são adenomatosos, pequenos e de localização distal.