Analysis Of Clinicopathological And Molecular Biological Characteristics Of Colorectal Cancer In Different Primary Sites

Objective:The purpose of this study is to compare the structural distribution,clinicopathologic and molecular characteristics of colorectal cancer in different primary sites,so as to provide basis for further study of left-sided colorectal cancer(LCRC)and right-sided colon cancer(RCC),explore the differences and possible favorable conclusions for guiding treatment and prognosis,and to guide individualized treatment colorectal cancer patients benefit.Methods: 134 patients diagnosed as colorectal cancer and treated with radical resection from January 1,2018 to June 30,2019 in our hospital were analyzed retrospectively.The patients' age,tumor location,serum tumor markers,tumor stage,pathological data and molecular characteristics were collected.The data were collected by Excel and analyzed by SPSS 23.0.Result:1.In this study,90 cases(67%)of left-sided colorectal cancer and 44 cases(33%)of right-sided colon cancer.There are more colorectal cancer in the LCRC than in the RCC.2.In terms of gender composition,the left-sided colorectal cancer group and the right-sided colon cancer group were more male than female patients,the difference was statistically significant(P = 0.022 < 0.05).But in the RCC,the proportion of female patients(47.7%)is higher than that of LCRC(27.8%).3.In this study,the proportion of left-sided colorectal cancer in patients under 60 years(37.8%)was higher than that of right-sided colon cancer(25.0%).The proportion of right colon cancer in patients over 60 years(75.0%)was higher than that of left-sided colorectal cancer(63.2%).There was no statistical difference in age of onset between the two groups(P > 0.05).4.The incidence of abdominal pain in the right-sided colon cancer group(81.8%)was higher than that in the left-sided colorectal cancer group(44.4%).The incidence of altered bowel habit in the left-sided colorectal cancer group(68.9%)was significantly higher than that in the right-sided colon cancer group(13.6%).The incidence of hematochezia in the left-sided colorectal cancer group(73.3%)was higher than that in the right-sided colon cancer group(15.9%).There were significant differences in abdominal pain,altered bowel habit and hematochezia between RCC and LCRC groups(P < 0.05).The incidence of intestinal obstruction in the right-sided colon cancer group(22.7%)was slightly higher than that in the left-sided colorectal cancer group(14.4%).The difference was not statistically significant between the RCC group and the LCRC group.The incidence of anemia in the RCC group before operation was(47.7%)higher than that in the LCRC group(32.2%).But the incidence of anemia did not differ significantly between the RCC group and the LCRC group.5.The abnormal composition of preoperative serum tumor markers CEA and CA199 in the RCC group was higher than that in the LCRC,but without significant difference.6.In terms of pathological characteristics,the composition ratio(56.8%)of tumors with a maximum diameter of> 5.0 cm in the right-sided colon cancer group was higher than that in the left-sided colorectal cancer group(45.6%),and the difference was not statistically significant.Colorectal cancer in different parts,there was no significant difference in the stages of TNM.The pathological classification of all colorectal cancers is the most common ulcerative type.The left-sided ulcerative colorectal cancer constitutes 82.2%,and the right-sided ulcerative colon cancer constitutes 77.3%,pathological types(ulcer and bulge)were not statistically different in each colorectal cancer group.The proportion of poorly differentiated,moderately-poorly differentiated adenocarcinomas in the RCC group(29.5%)was higher than that in the LCRC(14.4%).On the other hand,the composition ratio of highly differentiated,highly-differentiated adenocarcinoma in the LCRC group(17.8%)was higher than that in the RCC group(6.8%).The difference in the degree of pathological differentiation was statistically significant(P <0.05).The composition of mucinous adenocarcinoma components in RCC was significantly higher than that in LCRC,with significant differences(P < 0.05).7.In terms of molecular characteristics of immunohistochemistry,the expression rate of PD-L1 in the right-sided colon cancer group(25.0%)was significantly higher than that in the left-sided colorectal cancer group(5.6%),only the expression rate of PD-L1 was a marked difference between the two groups(P < 0.05),however,there was not a marked difference in the expression of PD-1,MLH1,MSH2,MSH6,PMS2,EGFR,Ki-67 and p53 between the different parts of colorectal cancer.In conclusion:1.The incidence of colorectal cancer in the left-sided of colorectal cancer patients admitted in our hospital is higher than that of right-sided colon cancer.2.The prevalence of colorectal cancer in men in different parts is higher than that of women,and women are more likely to develop right-sided colon cancer.3.Right-sided colon cancer is worse differentiated than left-sided colorectal cancer,and mucinous adenocarcinoma is more common.4.The positive expression rate of PD-L1 in right-sided colon cancer is higher,suggesting that patients with advanced right-sided colon cancer may relatively benefit from from the treatment of PD-L1 inhibitors.