The Effect Of Colon Melanosis On Colorectal Polyps And Colorectal Cancer

Objective:By collecting data on colorectal polyps and colorectal cancers in colon melanosis patients and non-colonic melanosis patients,the effect of colon melanosis on colorectal polyps and colorectal cancers was analyzed,and the attention of clinicians to melanosis of colon was enhanced.Methods:From January 2014 to January 2017,we selected 522 patients with colon melanosis from the 21,708 patients who underwent colonoscopy in our hospital to form an MC group, and selected 600 cases of non-colonic melanosis on a quarterly basis.,Final screening for 569eligible non-colonic melanosis groups.The age,sex,combined number of colorectal cancers,number of cases of colorectal polyps,pathological type,size,and location of polyps were collected and analyzed retrospectively.The non-normal distribution of measurement data was expressed as a median,and the rank sum test was used.The data of the two groups'counts(composition ratios)were analyzed by X2 test.P<0.05 considered the difference statistically significant.Results:There were 522 cases in the MC group,330 cases in females,192 cases in males,569 cases in non-MC group,235 cases in males and 334 cases in females.There was no statistical difference between the two groups(X~2=2.334,P=0.127,P>0.05).The ages of the two groups are non-normally distributed and the rank sum test is used,Z=-8.75,P<0.05,The median age of the colon melanosis group was 64 years(51 to 73 years),and the median age of the non-colonic melanosis group was 54 years(47 to 64 years). There was statistical difference between the two groups.250 and 229 cases of colorectal polyps were detected in MC and non-MC groups,respectively.The detection rates were 47.8%and 40.2%,respectively,P=0.013.The pathological type of the two groups were the lowest detection rate of inflammatory polyps,the highest detection rate of adenomatous polyps was 58.0%and 51.5%,no significant difference in pathological types;the detection rate in the cecum and descending colon were very low The detection rate of multiple sites,rectal and sigmoid colons was relatively high,but the difference was not statistically significant.The size of colorectal polyps was mainly concentrated in the range of 0-9mm.The percentages of the two groups were as high as 92.0%and 91.3%respectively.The detection rates of?20mm polyps were very low,which were 0.40%and 0.44%respectively.There was no significant difference in the size of polyps.In the MC and non-MC groups,13 cases(5.2%)and 10 cases(4.4%)were detected in colorectal cancer,and X2 value was 0.71.There was no significant difference in the detection rate of colorectal cancer between the two groups.conclusion:The detection rate of colorectal polyps with colon melanosis may be higher than that of non-colonic melanosis.Colon melanosis has no significant effect on the pathological type,location,size of colorectal polyps;colon melanosis may not have colorectal cancer influences.