DISCUSSION
polyp, CRC, cancer, polyps, CRC preventionThe
CANCER, CARCINOGENESIS
To reduce the incidence and mortality of CRC, it is essential that colonic polyps be removed at screening colonoscopies. Even with all the technological advances, a significant portion of these injuries remain unidentified. Digital chromoscopy has been proposed as a less laborious and faster alternative when compared with dye chromoscopy, but it has not demonstrated significant gains in polyp detection for the purposes of CRC preventionThe use of indigo carmine has already been described as a way of optimizing colonoscopy and examining specific areas of the colon suspected of having any alterationWe opted for chromoscopy with dye in a specific segment of the colon due to the easy anatomical characterization of the cecum and ascending colon (appendicular ostium, ileocecal valve, and hepatic flexure) and mainly because it is a segment where the protective value of colonoscopy is questioned. One of the explanations for this possible failure of protection is the predominance of flat lesions in the ascending colon, resulting in a higher incidence of interval cancer in the proximal colon, through the serrated pathway of carcinogenesisIn the present study, when summing the number of polyps (first and second evaluations), we found more than twice as many polyps in the chromoscopy group, a statistically significant difference. Lapalus et al.Nonetheless, in the present study, this increase was significant only in the group of patients undergoing colonoscopy with chromoscopy. Park et al.The proposal to use chromoscopy with indigo carmine is a simple and low-cost complementary method, bringing a summation effect to an examination that until then would be complete. Its potential in the detection of serrated-type flat lesions stands out, with its own pathway of carcinogenesis, involving mutation in RAS and BRAF, located mainly in the ascending colon, and very similar to the surrounding mucosa in most casesThe results of the present study show a gain in polyp detection when indigo carmine chromoscopy is used after conventional examination of the cecum and ascending colon, without additional risks, but with increased time. More prospective studies on the subject are awaited for a better understanding and to define its indication as CRC prevention.